You did a great job dealing with an individual that was predisposed to NOT understanding or liking the Shopsmith. I owned my own woodworking shop. Powermatic 66 saw, Powermatic Planner, Delta 6” jointer the whole bit. I sold off all my machines. Now I am in a wheelchair and I bought a clean Mark 5. Now I have FUN. Yes a Shopsmith is different and not for everyone. But as ones Shopsmith skills improve that’s when the machine shines! Thanks for all you did in sticking up for Shopsmith. Great Job! The guy has a myopic view of tooling & machinery. Making fun of something you don’t understand is not a good way to go thru life. WELL DONE!
Thanks for the support. I've met a few wheelchair bound Shopsmith users and some of them have removed the front bench tube to give themselves greater access. Have you made any modifications? Scott
I'm back! I circled back to this video today because I just bought a Coupler kit off "the bay" and it looks a bit like your vintage model. The bandsaw trainwreck I just bought, finally to be running today used a 5/8 redi-bolt coupler that had been drilled and tapped for setscrews. No hubs, no plastic, not nuttin'. Previous owner was proud of the coupler he made and turned on the machine to show it worked, I stepped way, way, way over to one side when he switched on his Frankenstein creation. Anywho, $120, I couldn't refuse, I had longer tubes, etc. at home from another project so I took it and got it down to my basement shop.
I’ve been watching your videos for a while you’re a very knowledgeable person on Shopsmith. I’ve had a 10 ER for years. Just got into a Mark five and already broke the coupler because it was stuck on to the bandsaw, but I do enjoy your videos. Thank you.
Great explanation, Scott. As you know, I was a demononstrator and teacher for Shopsmith and did tens of thousand of demonstrations. While I always carried a spare coupler, I don’t think I ever broke one. But I always recommended having a spare, ‘cause if you do break one, that could prevent you from using a SPT. Thanks again.
Hey Doug. I would guess that you've pretty much seen it all. I think in retrospect that I may have broken one that I left on a belt sander that later fell over, but who's fault was that? Just like Oreos, a spare is always a wise decision. Thanks for chiming in, Doug. BTW, what's with this new account? Scott
I purchased the new white coupler a few years ago because I didn't quite trust the old, used on that came with my 1984 Mark V. I was disappointed because I couldn't see through the nylon to determine where the splines were. I solved that issue by using a permanent marker to put lines on the outside of the coupler hubs where the splines are located. Makes for a much easier install. I also used the marker to define the writing on the side making that easier to read. Thanks for another great video. Your information is always appreciated, even by those of us who may already know it. Glen
If you and your son did a 3d printing channel id watch the heck out of it. You'd be so good at it. Its all of the same fiddly alignment, maintenance, yadda yadda. I would tripple dog dare you to make the channel but now that I think about it, thats really more for the cool kids and you just may not be big enough yet. I guess you could prove me wrong...
Hi Scott, I bought the MK-V new in ‘74,and all the accessories, including two power couplers. They are still going strong, and I have used them a lot. I think another reason for the spring is to absorb some of the shock when sliding the headstock to the side and into the coupler. The force can be quite strong sometimes. I have completely updated my system over the years, now a MK-VII with the power pro conversion. (That is a real game changer). Love it. It is so smooth ,QUIET, and powerful. I just designed and installed a lift with a linear actuator (electric) and what fun to watch the machine raise and lower without touching it. (Not sure I’ll get any work done 😊). By the way, I’m not related to the other Bittner of the Bittner Nut fame! Lol. John
That’s a very good point about the spring. It’s a shame you aren’t related to Bill or didn’t have the opportunity to meet him because I’m sure he would have loved to know another woodworking Bittner.
Zytel 101 is Duponts' general-purpose nylon 6/6, I have my original "power coupler" from '85 as well. I suspect the new couplers are Nylon as well and could easily determine that with a burn test. But I also suspect that they added a little color to the nylon because nylon breaks down molecularly in UV light, not just on the surface but as far as the light can penetrate so a little color will prevent that.
I too have a 1980ish model. Several of my prized shop tools have had non-replaceable plastic failures, in pristine condition, and had to be trashed. Consequently I purchased a coupler a few years ago. Now (knock on wood) I have two that work as intended :)
I want to thank you. - Your videos are going to be a major help to me in understanding this tool. Your explanations are well as if you worked for Shopsmith. Just picked up a Mark V from my Dad's good friend that passed on and had it since about the 80's if not earlier. It is sad - yet thankful that I have his Shopsmith for the time that I have to use it.
Hey Steve, it’s great to have you here. Sorry for the unfortunate circumstances around how you have joined the Shopsmith family, but it’s great to hear that someone will continue to enjoy your dad‘s friend’s tools. That is one interesting thing about Shopsmith tools; because it’s so well-made they often pass from one generation to the next to the next. That sure isn’t common with most of the tools that are being produced today. Scott
Scott, When I bought my coupler 20 years ago I thought this piece of plastic will eventually fail and bought 3. I'm still using the first one. Great design and function by Shopsmith.
Isn’t that funny! I think we all went through that with plastic product. A friend gifted me a plastic dial caliper in the 80’s which I accepted graciously, but in the back of my head I thought it would be in a landfill within months. Wouldn’t you know that the darn thing is still working and accurate and that I’ve purchased its digital brother! I guess it’s like plywood. We’ve all seen it used poorly, but when used properly it can be the best choice. Scott
I never analyzed the construction of the power coupler the way you did . .The safety rendered by adding the spring! Like other Shopsmith items, it shows ingenuity in design for safely and efficacy! I'll bet Jim McCann has studied the 3 D printer versions, but still uses Shopsmith originals. Keep up the great work, look forward to more videos.
I didn’t know that about the different hubs being for specific spindles. When I was setting up my 4” Jointer, I found that it would line up to the bottom spindle and the bottom spindle didn’t have a hub. I have two new Power Couples in the plastic bags and each has two hubs. I chose the closed cap hub (I chose correctly) and installed it on the lower spindle, got the Jointer lined up and it worked as it should .
If i was going to print that, with my limited experience, i would want to print it horizontally so the layer lines were in line with the rotation. You could get more torsional flex that way and increase the shear strength. I would think in this instance you would want to engineer your teeth as the week link. You can also print with nylon if you have an enclosure and the right printer. I haven't done it but i can say pretty confidently that pla is not the answer. This is all once again coming from an active noob in the grand scheme of things. Someone smarter than me can figure this out but it will require hundreds of dollars in equipment and tons of learning curve. Now that I think about it, it sounds right up a shosmithers alley. :)
"You forgot the lock down your headstock." Yep, happened to me when shooting my bandsaw video. Thought it was locked when it wasn't, and I though the blade slipped off the wheels at first when the saw stopped.
Okay Scott… you got my curiosity up. Are the new couplers that I bought last summer different from my old 1986? So, I studied them to find all the differences that I could. Here are some observations: 1. The mold has four sections. Two for internal and two for the outer shell. No upgrades appear to be made in the molds. The parts have (nearly) the same characteristics and cosmetic flaws. 2. The external finish of the body and bell section shows signs of being dressed up on the newer parts. If I shine a flashlight over the surface of the newer parts I can see polishing marks. The old part is slick as glass. 3. The mold flash was less on the old parts. That is even after accounting for trimming during processing. That could be due to variables of mold temperature, die pressure or injection force. But, experience tells me it is most likely wear on the alignment pins between three of the mold sections. (One inner and one outer seam is aligned much closer than the other three.) 4. The sprue orifices have different injection flow markings. The old part has a smoother set of flow lines than the new. It’s hard to tell why… but is likely due to the polishing having introduced radiuses or enlarged the injection site. 5. The parts have web stubs in the new ones, where they weren’t trimmed smoothly with the body surface. The old part has them really expertly trimmed off smooth. (These webs are normally used to connect two or more parts together in a multi-part mold. You know, like the web that connects model car parts .) 6 And most curiously… there is no mold cavity number. (Without that, I assume it is a single cavity mold.). I guess if I think about the cost to operate along with, the relatively short cycle time for a part this small, it makes sense. Because, the small volume sold isn’t likely to justify the expense of a multi-cavity mold. That would also mean the web stubs were used only for injection… and not for multiple parts. 7. Here is what else I did not find… the part had no date of manufacture, lot number or part number on it. It also didn’t have the obligatory recycling code molded into it! 8. The spring is not molded into the body. It is twisted into place afterward. This simplifies both the mold building and manufacturing processes significantly. All in all, the mold and the part design are time tested. They work well and the die itself appears to be sound. Thanks Scott for bringing this up… it’s been awhile since I did a close inspection on plastic moldings!
Very interesting observations indeed, Dave. My employer has a factory in Berlin Germany where they do zinc die casting, plastic injection molding and cold rolling of steel. I've visited a half dozen times and just love learning more and more about what they do. They have dozens of die casting machines with 64 cavities, and as you said, each cavity has a number and they are also required by law to include a signet, or hallmark. I also visited a factory in Bad Arolsen, Germany that does the smoothest polyamide nylon architectural parts you've ever seen. Their part lines are absolutely nonexistent. .
@@MyGrowthRings during the First Article Certification phase I maintained an inventory of the initial parts from each die, mold or machining process. These were extremely handy. I can’t count the number of times when we laid the First Article next to a current part and immediately knew what the problem was. And to your point… once you’ve seen precision manufacturing, you have a good sense of where the others rank!
I'm still using my original Power Couple that came with my new SS in March 1982. Earlier this month to celebrate our 40 together my SS got some wax and light weight oil and I had a couple of beers. Thanks for your great videos!
The idea is the same Kiekaffer Mercury had - OMC used a shear pin on the propeller shaft. Ok - but imagine hitting anything that would cause the pin to break and you’re out in rough water, miles or worse yards from land, you’ve gotta remove the propeller nut, you’re in salt water - basically you’re toast. Mercury developed a rubber hub in the propeller that would twist, slip under duress. It worked, works. I know. I hit many deadheads, sandbars, chunks of ice. The beauty was even low rpm it would slip. No more broken propeller blades, no loss of life due to a measly shear pin.
Thanks for the reminder. Picked up a set of couplers on the sale which ends tonight! Digging through my stuff I found one of the original kit boxes. "Power Mount Coupling Kit" Item no. 22 001 article no. 84-3462 printed on the side. I believe I have the coupler from it as well. Retired it long ago.
SOMETIMES .... I'll make a call on safety........THIS would NOT be one of those times !! I like being frugal and "experimenting" once in a while but this ole dawg knows better that to question things that are made specifically for my safety. THIS is obviously one of those choices !! There was a "2 fer" sale a while back and I now have an ORIGINAL in my "glass box" for emergencies !! I don't heal like I used to !! LOL !! Thanks for another great video !!
I ordered some 3d printed splines once. They go over the hubs and then you take PVC pipe and glue them in and the neat thing is you can make the pipe any length you want. The issue I had with them was the the printed piece that went over the hub had a very thin shelf that stopped it from sliding over the hub to far. Well on my accessory side the little shelf broke when I butted the machine up to hard one. then using it the coupler simply slid to far over the jointer and came off the head stock. But I was taking a healthy cut and as it pulled away the teeth on the head stock side stripped. But I liked the Idea and it could of been a easy fix in printing another but I never tried one again. Also they have some that you print the ends and then place a piece of 1 inch square hardwood stock like oak or maple in between. The neat thing if a person had a shortened Mark 5 you could have a bandsaw in the normal spot and a scroll saw on the other end. and make one long enough to go from the quell to the accessory on the right. Only thing is the one on the right is on backward so you need to use a tool that the direction of rotation does not matter. Like the scroll saw.
Great info as usual - I've been wondering about the different hubs - While on this subject I'd like to see a video on how to get some of the accessories aligned properly, thanks Scott.
Yes, we've printed quite a number of the SS files found on Thingiverse. I have no issue with prints of non-critical items, like switch keys and table inserts, but still have major reservations on the use of 3D printed couplings.
@@MyGrowthRings I can certainly understand that. I had not looked online at STL Files in a while.. They have some things that are petty cool. A lot more than the last time I looked.
@@MyGrowthRingsi do a decent amount of printing. I'm ok at it. I know people who I would consider trusting to make on of these but I'm not one of them. This seems like a good item to leave to someone else.
Scott, I have seen aftermarket printer couplers for sale on eBay, but have refrained due to the safety considerations you mention. I bought a pair from Shopsmith about 8 years ago because I was concerned the single one I had might fail. Plastic and all. I started using one of the the new ones and have not had to switch to the second back up coupler yet. They do last well. But I love knowing I have a backup. When and if the current one fails, I will buy a backup from Shopsmith (probably to be part of my estate when I pass!).
I picked up a belt sander and jointer from a knock-off Menards "Shopsmith" at a garage sale. Interesting difference was that the hub only had 4 spline grooves. Spent a little time making grooves with a file and then it worked great.
I used to have a manual for that machine. I've never played with one in person and I'm curious how close they got to SS with that one. Have you played with a Shopsmith to compare?
@@MyGrowthRings I only have the two Menards peripherals for my Shopsmith, so I can't judge the whole machine, but they seem well built. The 6x48" belt sander tracks nicely and the 6" jointer is a heavy beast compared to the Shopsmith version.
@@kenfcrafts I'm fairly sure that those were destined for Total Shop when they closed their doors. I have both of those tools too and you aren't kidding about that jointer!
another interesting micro topic! i also have a coupler from the 80's. red lettering faded but works great. i always wondered though, how hard to push it. once it's engaged i give it a pretty hard push. is it advisable to do that or leave some slack? interesting comment on why the spring is there. i always thought it was to prevent too tight a fit. but the safety thing makes sense.
Good to know, bought my Shop Smith a couple years ago. It had a coupler but given the age of the machine. I am wondering if I should at some point in the not too distant future. Replace it because, if it is the original then it’s more that 60 years old, even nylon breaks down over time. It looks fine but how do I know that it has not been abused at some point.
@@MyGrowthRings that’s what i am finding with my recent exploration into all things ShopSmith. Every thing seems to last a lot longer than is expected. That is rare these days. Every thing seems to be built and planned for self destruction, some of my Milwaukee tools really last. I have a saws all that I used on a daily bases for 35 years. It’s still going strong.
Regarding 3D printing. You don’t have to print that coupler vertically. It can be printed horizontally (or at an angle) to change shear points. PLA is a good filament for prototypes but there are many nylon filaments available, though you’ll probably need to modify your printer to handle them. The spring can even be printed. If you create a prototype you like, but want it in nylon without upgrading your printer, there are sites that will take your design (.stl) and use the filament of your choice and I presume at a price less than the mothership. Your “infill” can be a bit misleading. You can design your piece with many “walls” and it can be VERY strong. Get a license to use TinkerCad (free) and possibly Fusion 360 (it can also be free - it’s under the AutoCAD umbrella). Then while you are out on the road, use the hotel time to design and refine and play at making jigs! Good luck!
Another great video. I have one of the rubber coupler, but I use the plastic one. Btw, you didnt use your earphones. Your mike on the camera was great ,when you were facing the camera....but when you turned away ...... Cheers Jeffrey
Thanks for noticing, Jeffrey. Yeah, I have a new phone and it doesn't have the app that I normally use that allows me to shoot vids with my Air-buds for mics. I need to move past this because I know how much I dislike videos with poor sound. Scott
The other feature of a 3D printer would be for those parts no longer available from the Mothership. I have seen 3D printed bits and bobs for the old Mark VII.
Absolutely! Cams for the Mark VII were completely unavailable and custom ones (usually from aluminum) were out of reach and noisy, so 3-D printing is the perfect solution for them.
I had a coupler crack a few months ago. Not sure why. In the end I don’t think i had it fully seated on the Bandsaw. Im still not 100% sure though. 🤷♂️. I did end up ordering a new one & now I make sure everything is seated snugly.
I like to have an extra on hand. No need to go crazy about it, but the next time they go on sale or you see once at a reasonable price on eBay or Craigslist I'd suggest snatching it up. Scott
Sounds like it’s time for R&D. Shopsmith could easily test and engineer (and probably already have that data) so that a 3D printed coupler could fail in the same manner and at the same torque as the nylon couplers. And it could be designed with a spring for the headstock end. They could design the walls to have a certain thickness and have enough hollow space to be able to force failures to a specific area on the coupler. Maybe time to call Jim McCann?
I talked with Jim about 3D printing while I was visiting the factory last year. There are several products that they could be printing. I’m curious how much the current plastic injection molded coupler cost them to produce.
@@MyGrowthRings: pennies. However, look closely at the part and notice how little flash there is and how nice the finish. Thank the machinists for holding the extremely tight tolerance, and DS for replacing the dies when wear occurs. (I didn't work in shops that manufactured nylon parts but have read/been told it is very rough on the die.) But SD prices are too high for me and I dearly wish they could offer more affordable bits and parts.
That’s a very good question. Unfortunately, the way 3-D printer works for exact duplicate would not be strong enough. So the printed couplers are always chunky.
For the reasons you point out, and based on my experience with 3d printers I don't think the 3d printed one would work very well. It might work if you went to 100% infill, but 3d prints are weak to twisting force. Btw, having thicker walls (more wall line count) is stronger than more infill. You can adjust that in the slicer settings. I do think that the 3d printer should be on this channel, especially if you are showing how to combine it with your other tools. I am currently designing a 3d printed clamp (because you can never have too many clamps, heck I even have a podcast named CLAMP, lol) and once I get something that I am proud of I will be making a video.
I tried out a printed coupler. It worked quite well but eventually I got a bandsaw blade to bind and the coupler twisted apart. That's just what it should have done, the bandsaw blade could have snapped. However, I think a lesser jolt might have caused it to break anyway when not necessary.
I only use printed ones. When I purchased my ShopSmith it didn't come with one so I printed a few. I'm still using the first one that I printed, with PLA+ filament. 50% infill, nothing special.
My hub came off while disconnecting my band saw. how to get that hub out of the coupler? I drilled a hole right where the allen screw was sitting, tightened it back up on the band saw and was able to get it off. Whew!! I need to purchase an extra coupler lol. Is there any better ideas out there for this dilemma?
I will probably hate myself for this, 🤞, I have not lost my coupler from 1990. (Check back tomorrow). I put a 1” nylon cable clamp on the leg, the coupler snaps right in and it’s right at hand.
The spring…… I find with my hub the spring barely lets the splines engage. I have to really push to get about 1/2” engagement. Could I have the wrong hub on the headstock? It’s the one that came on it when i bought it new.
Could be. Does the headstock hub have four splines? If not, its flipped end for end and the spring will need to be switched over. Hope that's the case. Scott
Hi Scott, thanks for the info! I inherited a Mark 2 from my grandfather a few years ago (yep, I got the mutant unicorn). We couldn't find the coupler. Does the Mark 2 use same coupler? If so I will order it but wanted to confirm since I have the mutant. Thank you for the input!
Bought two brand-new 3D-printed couplers on Ebay. Tried to cut some 4" soft maple. Both shattered within seconds, even though the seller claimed they were "Stronger than the original-GUARANTEED!". Pure junk.
Hi Scott, Thanks for another informative video. I recall getting a coupler with each SPT that I have purchased. Not sure if they came with the tool or if I ordered them separately. Being In Canada with the exchange and shipping it makes sense to combine orders. So I do have a few spares. And a collection of SPTs. Three of which are mounted on individual power stations two of which I found in the used market in western Canada talk about a score. I do have a question relating to the spring. I always use it when mounting a tool on the mark v, but have removed them from the tools mounted on the power stations. Primarily because with the spring there seemed to be a bit of pressure on the bandsaw, strip-sander, and belt sander. That introduces a bit of deflection or lean. Do you see any issues with running these SPTs on the power station sans the spring? Thanks Ron in Western Canada
Prior to 1985 SS included a coupler with each SPT, but they dropped that and instead started adding one to Mark V purchases. When did your order your SPTs?
@@MyGrowthRings I do-not recall specific dates, sometime around the mid 80s, but I did two major purchases, I ordered a mark 5 the year before the 510 was introduced. That purchase included a bandsaw jointer and belt sander. The following year I purchased the 510 and sold the 500. I do not recall what I purchased along with the 510 but I have since added a strip sander, free standing scroll saw and the self powered pro planner. As well as the 3 power stations.
Pretty sure Elon has the mark 7 with the digital headstock! Gosh.... jokes aside, why would it be dangerous to have a coupler made of metal that can't break off? When my bandsaw jams up the motor just hums or possibly spins the belt until i turn it off, the coupler never breaks. When would this coupler even break and why?
There are redundant safety points, and you are right, your specific machine may default to another safety point, but in the case of the earliest Mark Vs with the Gilmer drive belt you can damage a fiber clutch or even the belt. On the mechanical Mark V’s since the 1960’s introduction of the poly-v belt, the belt will likely slip, assuming it is properly tensioned. Anyway, if the belt slips often the belt can be damaged. Why would it ever break? I have only experienced it once and that was while planing on a Mark V mounted planer taking a 1/8 depth of cut on a narrow board when the cutter head hit a HARD as nails knot, which stopped the cutter head cold! I believe I even had the sawblade on the table saw and I was lucky that I didn’t snap the double bearing quill. Anyway, the cheapest component broke, and that’s a good thing. Scott
I have the Power Pro headstock and the lift assist accessory (which is a must with the Power Pro in my opinion). I had an occasion where I wanted to run my bandsaw on the quill side rather than on the customary side. Alas the power coupler isn't long enough to connect the two due to the brackets for the lift assist. I would like the mother ship to create a power coupler that would "meet up" with this arrangement.
That would only work with the Power Pro running in reverse. The other Mark V, 505, 510, and 520 would not work because the hub is running in the wrong direction. It could create a safety issue if used improperly. I think the Old Mark 7 had a reversible motor but I’m not sure. If you think the current one is pricey, can you imagine how much more it would be for one the could only be used on the Power Pro?
@@daveschmitt6369 I know the bandsaw would run in reverse with the standard head stock but the Power Pro is reversible. I can’t see a modified design of the current coupler would be obscenity expensive as you suggest. IMHO
Dwight, I also have a lift assist, but I never considered that would cause that issue. If I really wanted to do that I think I might add a drive hub to a molder/dado arbor on the quill. Would that give you enough reach? Scott
@@MyGrowthRings I had the chance today to configure the bandsaw to the right of the headstock. With drive hub fully on the drive spindle, the drive hub even with the end of the of the shaft on the bandsaw and the coupler fully on the bandsaw hub, maybe with a new coupling it may engage the spindle drive hub but not by much. But, and there is most always a but, I have the mounting tube offsets on the bandsaw (so headstock can be tilted to drill press position with the bandsaw mounted normally) which does position the bandsaw perhaps 1 1/2" further away from the headstock. Without the offset option the coupling would engage properly to both hubs. Which brings up a question: I heard somewhere that with the standard mounting tubes on the bandsaw and tilting the bandsaw table to a full 45 degrees the headstock can be raised to the upright drilling position and will just "squeak" by. I haven't tried that but perhaps someone can verify if that is truth or fiction.
You did a great job dealing with an individual that was predisposed to NOT understanding or liking the Shopsmith. I owned my own woodworking shop. Powermatic 66 saw, Powermatic Planner, Delta 6” jointer the whole bit. I sold off all my machines. Now I am in a wheelchair and I bought a clean Mark 5. Now I have FUN. Yes a Shopsmith is different and not for everyone. But as ones Shopsmith skills improve that’s when the machine shines! Thanks for all you did in sticking up for Shopsmith. Great Job! The guy has a myopic view of tooling & machinery. Making fun of something you don’t understand is not a good way to go thru life. WELL DONE!
Thanks for the support. I've met a few wheelchair bound Shopsmith users and some of them have removed the front bench tube to give themselves greater access. Have you made any modifications? Scott
I'm back! I circled back to this video today because I just bought a Coupler kit off "the bay" and it looks a bit like your vintage model. The bandsaw trainwreck I just bought, finally to be running today used a 5/8 redi-bolt coupler that had been drilled and tapped for setscrews. No hubs, no plastic, not nuttin'. Previous owner was proud of the coupler he made and turned on the machine to show it worked, I stepped way, way, way over to one side when he switched on his Frankenstein creation. Anywho, $120, I couldn't refuse, I had longer tubes, etc. at home from another project so I took it and got it down to my basement shop.
Glad you stepped back!
I’ve been watching your videos for a while you’re a very knowledgeable person on Shopsmith. I’ve had a 10 ER for years. Just got into a Mark five and already broke the coupler because it was stuck on to the bandsaw, but I do enjoy your videos. Thank you.
Wow, free is a great price! Make sure the hubs are properly aligned and put some paste wax on them to keep them clean and rust free. Scott
Great explanation, Scott. As you know, I was a demononstrator and teacher for Shopsmith and did tens of thousand of demonstrations. While I always carried a spare coupler, I don’t think I ever broke one. But I always recommended having a spare, ‘cause if you do break one, that could prevent you from using a SPT. Thanks again.
Hey Doug. I would guess that you've pretty much seen it all. I think in retrospect that I may have broken one that I left on a belt sander that later fell over, but who's fault was that? Just like Oreos, a spare is always a wise decision. Thanks for chiming in, Doug. BTW, what's with this new account? Scott
I purchased the new white coupler a few years ago because I didn't quite trust the old, used on that came with my 1984 Mark V. I was disappointed because I couldn't see through the nylon to determine where the splines were. I solved that issue by using a permanent marker to put lines on the outside of the coupler hubs where the splines are located. Makes for a much easier install. I also used the marker to define the writing on the side making that easier to read. Thanks for another great video. Your information is always appreciated, even by those of us who may already know it. Glen
Good idea marking the splines. 👍
I did the same on one of mine!
I have done the exact same thing to mark the location of the splines. Super handy.
If you and your son did a 3d printing channel id watch the heck out of it. You'd be so good at it. Its all of the same fiddly alignment, maintenance, yadda yadda. I would tripple dog dare you to make the channel but now that I think about it, thats really more for the cool kids and you just may not be big enough yet. I guess you could prove me wrong...
Hi Scott, I bought the MK-V new in ‘74,and all the accessories, including two power couplers. They are still going strong, and I have used them a lot. I think another reason for the spring is to absorb some of the shock when sliding the headstock to the side and into the coupler. The force can be quite strong sometimes. I have completely updated my system over the years, now a MK-VII with the power pro conversion. (That is a real game changer). Love it. It is so smooth ,QUIET, and powerful. I just designed and installed a lift with a linear actuator (electric) and what fun to watch the machine raise and lower without touching it. (Not sure I’ll get any work done 😊). By the way, I’m not related to the other Bittner of the Bittner Nut fame! Lol. John
That’s a very good point about the spring. It’s a shame you aren’t related to Bill or didn’t have the opportunity to meet him because I’m sure he would have loved to know another woodworking Bittner.
Zytel 101 is Duponts' general-purpose nylon 6/6, I have my original "power coupler" from '85 as well. I suspect the new couplers are Nylon as well and could easily determine that with a burn test. But I also suspect that they added a little color to the nylon because nylon breaks down molecularly in UV light, not just on the surface but as far as the light can penetrate so a little color will prevent that.
I too have a 1980ish model. Several of my prized shop tools have had non-replaceable plastic failures, in pristine condition, and had to be trashed. Consequently I purchased a coupler a few years ago. Now (knock on wood) I have two that work as intended :)
I want to thank you. - Your videos are going to be a major help to me in understanding this tool. Your explanations are well as if you worked for Shopsmith. Just picked up a Mark V from my Dad's good friend that passed on and had it since about the 80's if not earlier. It is sad - yet thankful that I have his Shopsmith for the time that I have to use it.
Hey Steve, it’s great to have you here. Sorry for the unfortunate circumstances around how you have joined the Shopsmith family, but it’s great to hear that someone will continue to enjoy your dad‘s friend’s tools. That is one interesting thing about Shopsmith tools; because it’s so well-made they often pass from one generation to the next to the next. That sure isn’t common with most of the tools that are being produced today. Scott
@@MyGrowthRings This is good to know. I will start the reassembly tomorrow after I do the oil points to the HS motor and cleanup all the parts.
Scott, When I bought my coupler 20 years ago I thought this piece of plastic will eventually fail and bought 3. I'm still using the first one. Great design and function by Shopsmith.
Isn’t that funny! I think we all went through that with plastic product. A friend gifted me a plastic dial caliper in the 80’s which I accepted graciously, but in the back of my head I thought it would be in a landfill within months. Wouldn’t you know that the darn thing is still working and accurate and that I’ve purchased its digital brother! I guess it’s like plywood. We’ve all seen it used poorly, but when used properly it can be the best choice. Scott
I never analyzed the construction of the power coupler the way you did . .The safety rendered by adding the spring! Like other Shopsmith items, it shows ingenuity in design for safely and efficacy! I'll bet Jim McCann has studied the 3 D printer versions, but still uses Shopsmith originals. Keep up the great work, look forward to more videos.
Thanks James. Yeah, I’m a nerd.
I didn’t know that about the different hubs being for specific spindles.
When I was setting up my 4” Jointer, I found that it would line up to the bottom spindle and the bottom spindle didn’t have a hub. I have two new Power Couples in the plastic bags and each has two hubs. I chose the closed cap hub (I chose correctly) and installed it on the lower spindle, got the Jointer lined up and it worked as it should .
Woohoo! Better late than never. Scott
If i was going to print that, with my limited experience, i would want to print it horizontally so the layer lines were in line with the rotation. You could get more torsional flex that way and increase the shear strength. I would think in this instance you would want to engineer your teeth as the week link. You can also print with nylon if you have an enclosure and the right printer. I haven't done it but i can say pretty confidently that pla is not the answer. This is all once again coming from an active noob in the grand scheme of things. Someone smarter than me can figure this out but it will require hundreds of dollars in equipment and tons of learning curve. Now that I think about it, it sounds right up a shosmithers alley. :)
"You forgot the lock down your headstock." Yep, happened to me when shooting my bandsaw video. Thought it was locked when it wasn't, and I though the blade slipped off the wheels at first when the saw stopped.
It has happened to all of us.
@@thebeggarswoodshop8756
Yepper, Happened to me!!
I still use the rubber and aluminum coupler that came with my greenie in 1954.
That’s crazy yet quite impressive.
Okay Scott… you got my curiosity up. Are the new couplers that I bought last summer different from my old 1986?
So, I studied them to find all the differences that I could. Here are some observations:
1. The mold has four sections. Two for internal and two for the outer shell. No upgrades appear to be made in the molds. The parts have (nearly) the same characteristics and cosmetic flaws.
2. The external finish of the body and bell section shows signs of being dressed up on the newer parts. If I shine a flashlight over the surface of the newer parts I can see polishing marks. The old part is slick as glass.
3. The mold flash was less on the old parts. That is even after accounting for trimming during processing. That could be due to variables of mold temperature, die pressure or injection force. But, experience tells me it is most likely wear on the alignment pins between three of the mold sections. (One inner and one outer seam is aligned much closer than the other three.)
4. The sprue orifices have different injection flow markings. The old part has a smoother set of flow lines than the new. It’s hard to tell why… but is likely due to the polishing having introduced radiuses or enlarged the injection site.
5. The parts have web stubs in the new ones, where they weren’t trimmed smoothly with the body surface. The old part has them really expertly trimmed off smooth. (These webs are normally used to connect two or more parts together in a multi-part mold. You know, like the web that connects model car parts .)
6 And most curiously… there is no mold cavity number. (Without that, I assume it is a single cavity mold.). I guess if I think about the cost to operate along with, the relatively short cycle time for a part this small, it makes sense. Because, the small volume sold isn’t likely to justify the expense of a multi-cavity mold. That would also mean the web stubs were used only for injection… and not for multiple parts.
7. Here is what else I did not find… the part had no date of manufacture, lot number or part number on it. It also didn’t have the obligatory recycling code molded into it!
8. The spring is not molded into the body. It is twisted into place afterward. This simplifies both the mold building and manufacturing processes significantly.
All in all, the mold and the part design are time tested. They work well and the die itself appears to be sound. Thanks Scott for bringing this up… it’s been awhile since I did a close inspection on plastic moldings!
Very interesting observations indeed, Dave. My employer has a factory in Berlin Germany where they do zinc die casting, plastic injection molding and cold rolling of steel. I've visited a half dozen times and just love learning more and more about what they do. They have dozens of die casting machines with 64 cavities, and as you said, each cavity has a number and they are also required by law to include a signet, or hallmark.
I also visited a factory in Bad Arolsen, Germany that does the smoothest polyamide nylon architectural parts you've ever seen. Their part lines are absolutely nonexistent. .
@@MyGrowthRings during the First Article Certification phase I maintained an inventory of the initial parts from each die, mold or machining process. These were extremely handy. I can’t count the number of times when we laid the First Article next to a current part and immediately knew what the problem was.
And to your point… once you’ve seen precision manufacturing, you have a good sense of where the others rank!
Fascinating…
@@alberttreado3713 thanks… geeking out on such an obscure subject is a bad habit of mine!
@@sassafrasvalley1939 You have never seen how a printer (my field) geeks out over looking over a printed sheet...
I'm still using my original Power Couple that came with my new SS in March 1982. Earlier this month to celebrate our 40 together my SS got some wax and light weight oil and I had a couple of beers. Thanks for your great videos!
Sounds like you two had a very nice celebration! Scott
The idea is the same Kiekaffer Mercury had - OMC used a shear pin on the propeller shaft. Ok - but imagine hitting anything that would cause the pin to break and you’re out in rough water, miles or worse yards from land, you’ve gotta remove the propeller nut, you’re in salt water - basically you’re toast.
Mercury developed a rubber hub in the propeller that would twist, slip under duress.
It worked, works. I know. I hit many deadheads, sandbars, chunks of ice. The beauty was even low rpm it would slip. No more broken propeller blades, no loss of life due to a measly shear pin.
@@johnrice4273 There’s a similar shear pin in my pellet smoker. It’s funny how hard this is for some (JM) to comprehend.
Thanks for the reminder. Picked up a set of couplers on the sale which ends tonight!
Digging through my stuff I found one of the original kit boxes. "Power Mount Coupling Kit" Item no. 22 001 article no. 84-3462 printed on the side. I believe I have the coupler from it as well. Retired it long ago.
Very cool!
SOMETIMES .... I'll make a call on safety........THIS would NOT be one of those times !! I like being frugal and "experimenting" once in a while but this ole dawg knows better that to question things that are made specifically for my safety. THIS is obviously one of those choices !! There was a "2 fer" sale a while back and I now have an ORIGINAL in my "glass box" for emergencies !! I don't heal like I used to !! LOL !!
Thanks for another great video !!
Wise man.
My coupler is going strong since 1981.
I ordered some 3d printed splines once. They go over the hubs and then you take PVC pipe and glue them in and the neat thing is you can make the pipe any length you want. The issue I had with them was the the printed piece that went over the hub had a very thin shelf that stopped it from sliding over the hub to far. Well on my accessory side the little shelf broke when I butted the machine up to hard one. then using it the coupler simply slid to far over the jointer and came off the head stock. But I was taking a healthy cut and as it pulled away the teeth on the head stock side stripped. But I liked the Idea and it could of been a easy fix in printing another but I never tried one again. Also they have some that you print the ends and then place a piece of 1 inch square hardwood stock like oak or maple in between. The neat thing if a person had a shortened Mark 5 you could have a bandsaw in the normal spot and a scroll saw on the other end. and make one long enough to go from the quell to the accessory on the right. Only thing is the one on the right is on backward so you need to use a tool that the direction of rotation does not matter. Like the scroll saw.
Have you visited Shapeways.com?
I have a 1963 Mark 7 my dad bought new. It still runs great. And I still use the original coupler. I'd say they last a long time.
Wow! I was also made in 63 and I'm nowhere near my original condition!
Great info as usual - I've been wondering about the different hubs - While on this subject I'd like to see a video on how to get some of the accessories aligned properly, thanks Scott.
Thanks Tim. I believe I covered that on a Strip Sander vid, but you are right, that topic probably deserves it's own video. Good idea. Scott
lots of shop smith part files made out there. Like the insert on the table of the bandsaw. plastic runners to make sleds and a lot more.
Yes, we've printed quite a number of the SS files found on Thingiverse. I have no issue with prints of non-critical items, like switch keys and table inserts, but still have major reservations on the use of 3D printed couplings.
@@MyGrowthRings I can certainly understand that. I had not looked online at STL Files in a while.. They have some things that are petty cool. A lot more than the last time I looked.
@@MyGrowthRingsi do a decent amount of printing. I'm ok at it. I know people who I would consider trusting to make on of these but I'm not one of them. This seems like a good item to leave to someone else.
@@WoodworkingforAnyone I concur
Thanks, Scott, excellent as usual!
Thanks, John.
Fascinating…
AN ENJOYABLE EPISODE!
Thanks, John.
Scott,
I have seen aftermarket printer couplers for sale on eBay, but have refrained due to the safety considerations you mention. I bought a pair from Shopsmith about 8 years ago because I was concerned the single one I had might fail. Plastic and all. I started using one of the the new ones and have not had to switch to the second back up coupler yet. They do last well. But I love knowing I have a backup. When and if the current one fails, I will buy a backup from Shopsmith (probably to be part of my estate when I pass!).
I totally relate. I think you are reasonable. Scott
I picked up a belt sander and jointer from a knock-off Menards "Shopsmith" at a garage sale. Interesting difference was that the hub only had 4 spline grooves. Spent a little time making grooves with a file and then it worked great.
I used to have a manual for that machine. I've never played with one in person and I'm curious how close they got to SS with that one. Have you played with a Shopsmith to compare?
@@MyGrowthRings I only have the two Menards peripherals for my Shopsmith, so I can't judge the whole machine, but they seem well built. The 6x48" belt sander tracks nicely and the 6" jointer is a heavy beast compared to the Shopsmith version.
@@kenfcrafts I'm fairly sure that those were destined for Total Shop when they closed their doors. I have both of those tools too and you aren't kidding about that jointer!
another interesting micro topic! i also have a coupler from the 80's. red lettering faded but works great. i always wondered though, how hard to push it. once it's engaged i give it a pretty hard push. is it advisable to do that or leave some slack? interesting comment on why the spring is there. i always thought it was to prevent too tight a fit. but the safety thing makes sense.
I think that the spring provides plenty of space for that margin of safety, but I’ll explore further with Jim McCann.
Good to know, bought my Shop Smith a couple years ago. It had a coupler but given the age of the machine. I am wondering if I should at some point in the not too distant future. Replace it because, if it is the original then it’s more that 60 years old, even nylon breaks down over time. It looks fine but how do I know that it has not been abused at some point.
It wouldn’t be a bad idea to have a spare ready, but that age doesn’t surprise me one bit.
@@MyGrowthRings that’s what i am finding with my recent exploration into all things ShopSmith. Every thing seems to last a lot longer than is expected. That is rare these days. Every thing seems to be built and planned for self destruction, some of my Milwaukee tools really last. I have a saws all that I used on a daily bases for 35 years. It’s still going strong.
Regarding 3D printing. You don’t have to print that coupler vertically. It can be printed horizontally (or at an angle) to change shear points. PLA is a good filament for prototypes but there are many nylon filaments available, though you’ll probably need to modify your printer to handle them. The spring can even be printed. If you create a prototype you like, but want it in nylon without upgrading your printer, there are sites that will take your design (.stl) and use the filament of your choice and I presume at a price less than the mothership. Your “infill” can be a bit misleading. You can design your piece with many “walls” and it can be VERY strong.
Get a license to use TinkerCad (free) and possibly Fusion 360 (it can also be free - it’s under the AutoCAD umbrella). Then while you are out on the road, use the hotel time to design and refine and play at making jigs!
Good luck!
I appreciate the insights. I really do believe that there are many practical uses for this printer.
Thanks, good information.
You are welcome, Brad. Thanks for watching and commenting! Scott
Another great video. I have one of the rubber coupler, but I use the plastic one. Btw, you didnt use your earphones. Your mike on the camera was great ,when you were facing the camera....but when you turned away ......
Cheers
Jeffrey
Thanks for noticing, Jeffrey. Yeah, I have a new phone and it doesn't have the app that I normally use that allows me to shoot vids with my Air-buds for mics. I need to move past this because I know how much I dislike videos with poor sound. Scott
October 1987...about the time I purchased my MK V...used (1970s serial #)
I will always remember the week, because I bought it the day the stock market crashed!
The other feature of a 3D printer would be for those parts no longer available from the Mothership. I have seen 3D printed bits and bobs for the old Mark VII.
Absolutely! Cams for the Mark VII were completely unavailable and custom ones (usually from aluminum) were out of reach and noisy, so 3-D printing is the perfect solution for them.
Have you ever seen a coupler break cause of old age? Are back up couplers needed to have on hand?
I had a coupler crack a few months ago. Not sure why. In the end I don’t think i had it fully seated on the Bandsaw. Im still not 100% sure though. 🤷♂️. I did end up ordering a new one & now I make sure everything is seated snugly.
I like to have an extra on hand. No need to go crazy about it, but the next time they go on sale or you see once at a reasonable price on eBay or Craigslist I'd suggest snatching it up. Scott
That would do it. I always make sure that they are deeply seated. Hopefully you and your new coupler will have a long life together. Scott
Sounds like it’s time for R&D. Shopsmith could easily test and engineer (and probably already have that data) so that a 3D printed coupler could fail in the same manner and at the same torque as the nylon couplers. And it could be designed with a spring for the headstock end. They could design the walls to have a certain thickness and have enough hollow space to be able to force failures to a specific area on the coupler. Maybe time to call Jim McCann?
I talked with Jim about 3D printing while I was visiting the factory last year. There are several products that they could be printing. I’m curious how much the current plastic injection molded coupler cost them to produce.
@@MyGrowthRings: pennies. However, look closely at the part and notice how little flash there is and how nice the finish. Thank the machinists for holding the extremely tight tolerance, and DS for replacing the dies when wear occurs. (I didn't work in shops that manufactured nylon parts but have read/been told it is very rough on the die.)
But SD prices are too high for me and I dearly wish they could offer more affordable bits and parts.
If your going to 3d print a coupling why not make it an exact duplicate?
That’s a very good question. Unfortunately, the way 3-D printer works for exact duplicate would not be strong enough. So the printed couplers are always chunky.
For the reasons you point out, and based on my experience with 3d printers I don't think the 3d printed one would work very well. It might work if you went to 100% infill, but 3d prints are weak to twisting force. Btw, having thicker walls (more wall line count) is stronger than more infill. You can adjust that in the slicer settings. I do think that the 3d printer should be on this channel, especially if you are showing how to combine it with your other tools. I am currently designing a 3d printed clamp (because you can never have too many clamps, heck I even have a podcast named CLAMP, lol) and once I get something that I am proud of I will be making a video.
Actually, my son mentioned that it has three walls. All good points. Scott
I tried out a printed coupler. It worked quite well but eventually I got a bandsaw blade to bind and the coupler twisted apart. That's just what it should have done, the bandsaw blade could have snapped. However, I think a lesser jolt might have caused it to break anyway when not necessary.
I only use printed ones. When I purchased my ShopSmith it didn't come with one so I printed a few. I'm still using the first one that I printed, with PLA+ filament. 50% infill, nothing special.
@@1D10CRACY I'm surprised! I would have thought that it would split at the layer lines!
@@TheGrantAlexander my layers fuse together rather well, not really sure why other than I sometimes benefit from dumb luck. :)
My hub came off while disconnecting my band saw. how to get that hub out of the coupler? I drilled a hole right where the allen screw was sitting, tightened it back up on the band saw and was able to get it off. Whew!! I need to purchase an extra coupler lol. Is there any better ideas out there for this dilemma?
I use the “Shopsmith Toolbox” (hex wrench) driven through the opposite end to tap it out. It isn’t easy, but it’s doable.
I will probably hate myself for this, 🤞, I have not lost my coupler from 1990. (Check back tomorrow). I put a 1” nylon cable clamp on the leg, the coupler snaps right in and it’s right at hand.
Smart. It took me a moment to realize what you meant but I get it now. Very clever. Scott
The spring…… I find with my hub the spring barely lets the splines engage. I have to really push to get about 1/2” engagement. Could I have the wrong hub on the headstock? It’s the one that came on it when i bought it new.
Could be. Does the headstock hub have four splines? If not, its flipped end for end and the spring will need to be switched over. Hope that's the case. Scott
Hi Scott, thanks for the info! I inherited a Mark 2 from my grandfather a few years ago (yep, I got the mutant unicorn). We couldn't find the coupler. Does the Mark 2 use same coupler? If so I will order it but wanted to confirm since I have the mutant. Thank you for the input!
That’s really cool that you have your grandfather’s Shopsmith! Yes, the standard Shopsmith coupler kit is all you need.
@@MyGrowthRings awesome, on it!
I have lost all my fasteners to put together the vacuum Shopsmith system. Is there a kit to purchase all the fasteners? Thank you
Larry, the fasteners for the DC3300? Shopsmith probably has a hardware pack you can buy.
Murphy's Law: Critical parts will always fail right when you need them...
Exactly!
Bought two brand-new 3D-printed couplers on Ebay. Tried to cut some 4" soft maple. Both shattered within seconds, even though the seller claimed they were "Stronger than the original-GUARANTEED!". Pure junk.
@@jackgavin5989 I’ve seen those posted and was curious about them. Which SPT were you powering?
@@MyGrowthRings Bandsaw, using an almost new blade. Very disappointing. But the seller refunded my money immediately.
Hi Scott,
Thanks for another informative video.
I recall getting a coupler with each SPT that I have purchased. Not sure if they came with the tool or if I ordered them separately. Being In Canada with the exchange and shipping it makes sense to combine orders. So I do have a few spares. And a collection of SPTs.
Three of which are mounted on individual power stations two of which I found in the used market in western Canada talk about a score.
I do have a question relating to the spring. I always use it when mounting a tool on the mark v, but have removed them from the tools mounted on the power stations. Primarily because with the spring there seemed to be a bit of pressure on the bandsaw, strip-sander, and belt sander. That introduces a bit of deflection or lean. Do you see any issues with running these SPTs on the power station sans the spring?
Thanks
Ron in Western Canada
Prior to 1985 SS included a coupler with each SPT, but they dropped that and instead started adding one to Mark V purchases. When did your order your SPTs?
@@MyGrowthRings I do-not recall specific dates, sometime around the mid 80s, but I did two major purchases, I ordered a mark 5 the year before the 510 was introduced. That purchase included a bandsaw jointer and belt sander. The following year I purchased the 510 and sold the 500. I do not recall what I purchased along with the 510 but I have since added a strip sander, free standing scroll saw and the self powered pro planner.
As well as the 3 power stations.
So…gonna 3-D print a mini lathe for grandson?
That’s a very intriguing idea. Perhaps parts of it at least.
Pretty sure Elon has the mark 7 with the digital headstock! Gosh.... jokes aside, why would it be dangerous to have a coupler made of metal that can't break off? When my bandsaw jams up the motor just hums or possibly spins the belt until i turn it off, the coupler never breaks. When would this coupler even break and why?
There are redundant safety points, and you are right, your specific machine may default to another safety point, but in the case of the earliest Mark Vs with the Gilmer drive belt you can damage a fiber clutch or even the belt. On the mechanical Mark V’s since the 1960’s introduction of the poly-v belt, the belt will likely slip, assuming it is properly tensioned. Anyway, if the belt slips often the belt can be damaged. Why would it ever break? I have only experienced it once and that was while planing on a Mark V mounted planer taking a 1/8 depth of cut on a narrow board when the cutter head hit a HARD as nails knot, which stopped the cutter head cold! I believe I even had the sawblade on the table saw and I was lucky that I didn’t snap the double bearing quill. Anyway, the cheapest component broke, and that’s a good thing. Scott
I have the Power Pro headstock and the lift assist accessory (which is a must with the Power Pro in my opinion). I had an occasion where I wanted to run my bandsaw on the quill side rather than on the customary side. Alas the power coupler isn't long enough to connect the two due to the brackets for the lift assist. I would like the mother ship to create a power coupler that would "meet up" with this arrangement.
That would only work with the Power Pro running in reverse. The other Mark V, 505, 510, and 520 would not work because the hub is running in the wrong direction. It could create a safety issue if used improperly. I think the Old Mark 7 had a reversible motor but I’m not sure. If you think the current one is pricey, can you imagine how much more it would be for one the could only be used on the Power Pro?
@@daveschmitt6369 I know the bandsaw would run in reverse with the standard head stock but the Power Pro is reversible. I can’t see a modified design of the current coupler would be obscenity expensive as you suggest. IMHO
Yes, the 1960's Mark VII did run in reverse.
Dwight, I also have a lift assist, but I never considered that would cause that issue. If I really wanted to do that I think I might add a drive hub to a molder/dado arbor on the quill. Would that give you enough reach? Scott
@@MyGrowthRings I had the chance today to configure the bandsaw to the right of the headstock. With drive hub fully on the drive spindle, the drive hub even with the end of the of the shaft on the bandsaw and the coupler fully on the bandsaw hub, maybe with a new coupling it may engage the spindle drive hub but not by much. But, and there is most always a but, I have the mounting tube offsets on the bandsaw (so headstock can be tilted to drill press position with the bandsaw mounted normally) which does position the bandsaw perhaps 1 1/2" further away from the headstock. Without the offset option the coupling would engage properly to both hubs. Which brings up a question: I heard somewhere that with the standard mounting tubes on the bandsaw and tilting the bandsaw table to a full 45 degrees the headstock can be raised to the upright drilling position and will just "squeak" by. I haven't tried that but perhaps someone can verify if that is truth or fiction.