Rigid Mini Lathe Upgrade | Tapered Roller Bearings, Solid Tool Post, Brass Gib Strips Mod
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- Опубліковано 19 чер 2024
- G'day everyone,
I think that we can all agree that the biggest issues with regards to the 7 x 14 import mini lathes stem from their lack of rigidity and overall mass. At only 60kg in mass, they tend to struggle when it comes to cutting ferrous metals.
That is not to say that we can not improve what we have. Having used this lathe for over 2 years, I have identified several area where we can upgrade the mini lathes rigidity and improve cutting performance and see an improvement in surface finish.
I will be upgrading the spindle bearings to 30206 tapered roller bearings (for the lathe spindle), upgrading the saddle retaining plates, replacing the steel gib with a brass one, adjusting the grub screws and replacing the compound with a solid tool post.
Timestamps
0:00 - Intro
0:44 - Tapered Roller Bearings Upgrade
5:17 - Brass Gib Upgrade
6:43 - Gib Adjustment
7:09 - Saddle Retaining Plate Upgrade
9:13 - Solid Tool Post Upgrade
#machining #lathe #minilathe
I find it funny that the hobby in ones hobby shop is improving ones hobby shop by shopping for ones hobby shop. 😎
You can improve the performance of the mini lathe a hell of a lot by using techniques suited to the machine. If you look at 9:15 you see a fairly typical position that people end up in. The compound has pushed the tool way past the edge of the cross-slide so the force of cutting is like pushing down on the high end of a kids' see-saw. If you do that, the low end of the see-saw lifts off the ground. Push on the low end, even close to the pivot point and nothing happens. Your fixed support has moved the tool so it is about 1cm inside the cross slide, so the force is straight down to the bed of the machine and nothing wants to move. On a massive two ton machine you don't need to think about details like that but on these things you definitely do.
Greatly appreciated! This is the only model of lathe I will ever be able to afford and glad to see any improvements I should make when I make the leap and purchase one. Thanks again for the info.
Tapered roller bearings made huge difference for my lathe. Great video 👍
Hello friend, what difference did you have after you changed the bearing?
Me too, I was able to use the 'tiny' 1/4" deep parting tool without any problems after switching to taper bearings.
Excellent work. The improvements shown have convinced me that it's time I did this to my minilathe.
Kind of lost interest but after 2 years, I decided to upgrade the bearings. For anyone thats wondering, angular bearings are a direct swap. No other machining required on the spacers (Sieg SC3). Using a large F clamp helped press the bearings in, and also pressed the spindle shaft into the bearings. The difference is night and day.
What differences did you notice?
@@NagashiChidorii The factory bearings were quite bad, or mine was shot after years of abuse. Lots of chatter at short stickouts. I've machine hardened steel CV shafts on mine, motor barely keeps up but does a decent job.
Thanks for sharing the upgrade ideas! Definitely need to re-examine mine for these improvements!
Absolutely brilliant, enjoyed it a lot.
Looks like I got some shopping to do before I restore my HF mini lathe.
Thanks for sharing this info mate!
Just ordered new tapered roller bearing and a quick change toolpost, these results are way better than what I have now.
Really enjoying your videos, keep up the good work!
I'd argue that just getting a good surface finish on steel is an accomplishment for these machines...
These changes elevate it a step beyond
Oddly enough I find it incredibly easy to get a great surface finish on mild steel with mine. No clue why.
@@ScootyPuff_Jr some people have better gibs/etc from the factory, less warp in the bed, etc etc. Mine hasn't been able to do well with any steel yet (though I've been planning on doing all 3 of the things shown in this video for a while) even with adjustments to those components. Better quality tooling would make a difference too, as so far I've only used cheap carbide inserts and self ground HSS.
I could put a finished surface on steel straight out of the box with mine. Changing the bearings helped with turning long pieces. If I only worked pieces shorter than 3 inches, I wouldn’t have had to change anything.
Excellent job. I made the same upgrade to mine. It makes a lot of difference in rigidity and finish.
Hint…..changing the gears to metal makes no difference. It only cuts down on the sound level by a very small amount.
Smart upgrade ideas, thanks.
Great video. Getting Chinese and refurbishing is a good way to go on a budget. One detail that can be improved upon is to add locking screws to the gibb from the top. Use the side screws to get set the clearance and then lock them from the top. That way the gibb cannot move at all and adds to the rigidity.
Thanks for the video. Now I have to upgrade my Bernardo 400 Profi.
Wow great job, what an improvement.thanks for sharing.
Thanks for watching!
I bought my mini lathe in early 2000's and taper bearings were first thing I did to it.
The taper roller bearings made enough difference that parting off is no longer a teeth clenching affair waiting for tool to dig in and break something
I think that's the first time I've seen anyone make a new gib strip for mini lathe?
I have seen various articles over the years about re-locating or modifying the indents on gib and stoning to get better contact but I like your method a lot better.
I have a piece of silicon bronze big enough to make one so that will be next 'upgrade' (I used it for the saddle hold down clamps and have a piece left)
Do not measure looseness of the spindle with dial attached to the rail.
Measure it with the dial attached to the bearing housing.
You may have looseness coming from connection between the rail and the main body.....
You are right there and I should have known better. Sometimes I'm thinking too much lie a camera man and not enough like a machinist. Thanks for the correction. I will say that since both measurements were taken the same way we can say that a lot of the spindle movement was coming from the bearings. Cheers.
@@artisanmakes Good move on the solid Tool Post.
That's something both Stefan Gotteswinter and Joe Pieczynski recommend for any lathe. I think Robin Renzetti has also done the same.
In one if his vids Stefan points out how a solid tool post affects thread cutting. From memory the need to come on at an angle for each pass on the thread becomes almost irrelevant with a solid tool post because of the increased rigidity.
On the bearings did you consider using just 1 taper bearing and 1 angled contact?
It looks like you got a great result in the end.
If you ever want to see a great vid on how to improve a cheaper Asian machinery. Robin Renzetti bought one of those cheap D-Bit grinders and by the time he finished it was as good as a Deckel.
Wow very content dense episode! Lots of good points to consider.
Glad you enjoyed it!
Another great video dude,
Those upgrades really look like they have improved your overall rigidity. I imagine next time you part of a lot of that parting squeal you get from mini lathes will be gone.
All the best.
11:52 Great Job! thanks a lot for sharing, I liked a lot swaping the main bearings for the Timken, I will remove as well the auxiliary carousel, I think these two changes will improve the lathe near to minute 11:52. thanks again!
Thanks for a fine video
Outstanding!
I misunderstood the title and thought , "I didn't know RIGID made mini-lathes".
No worries as the content was informative and helpful, as usual.
Nice ones. But you overlooked one that's rather obvious!
Take notice at 2:00. There's ONLY 3 holes. Make a 4th hole, thread it set a bolt. It will increase rigidity against the bed. ;-)
Most builds of these "Chinese" mini lathe's do have the 4 holes on the headstock. But obviously not all. An easy and cheap improvement.
At 4:00, replace the plastic compression ring/spacer. With a suitable replacement made of metal. Brass, aluminium, steel... Metal pipe is a good cheap/easy option. Anything is better than plastic for this particular detail. Nice videos.
Cheers
Someone else pointednthis out too and I eventually did both of them, which helped reduce vibrations when turning at high speeds. Not sure why I missed this initially, but it is a solid upgrade. Cheers
Congratulations
I am planning on doing all of this and a bit more
Thank you this old tony.
Thanks, great advice
Glad it was helpful, cheers
That was chipping beautiful at the end, great job.ypu should make a fly cutter for your mill next.
Absolutely agree with the solid post. Unless you need the compound...
Some other things you can do;
USE A CENTRE! For anything more than a of 1:3 diameter to stick-out ratio, you really should. This applies if you’re turning a 10mm shaft or a 100mm shaft.
Choke right up on the insert holder: put that tool holder right back in the toolpost. With those smaller insert holders, the most they can practically work at is around 20mm stickout, and there is a noticeable difference if you reduce it to less than ~15 or so.
This also brings the toolpost closer to the tangent of the workpiece, allowing it to take more load, more easily.
Take deeper cuts, and feed it all she’ll suffer:
carbide loves load, if you go too gently it doesn’t like it, and will go dull and squeal in protest. Carbide also works better with either coolant, or dry, oil just shortens the lifespan of your lungs…
These are the principles i work with every day, and it allows me to work to 0.01mm tolerances, and sometimes less, without too much extra effort.
(Also PLEASE consider making that toolpost riser block out of **anything** other than aluminium ;~;)
Here’s to bigger and better lathes in your future :D
Thanks mate, feedback is always welcome. That mild steel was probably at its limit. 15mm probably stickling out a good 40 -45mm. With the tool holders you are right. The stick out is always hard to correctly determine. Too little and it doesn't look good on camera. Through I suspect the tool holders are a big part of the problem, they are made from mild. I have a kyocera tool holder and it is made from hardened steel. As for the alu tool riser, gotta work with what I have, but I don't think a steel one would give us too much of a difference, although that is just my speculation. Cheers
I have the same lathe, SieG branded. Put in taper bearings a few months ago. It took a while to get the preload just right, or the motor lost so much power cutting suffered big time.
WOW!!! So I can use aluminum to make a solid base for a tool post??? I have a micro (Sherline) lathe and wanted to make some betterments to it but always thought aluminum wouldn’t hold!!!! I’m just an apprentice on my own and amazed for all you can do!!! I just got a “mill attachment” to try making such things but still afraid of using it due to lack of rigidity, something I was warned by the previous owner and confirmed by some others but will have to try it.
Thank you for your videos! They are super helpful!!!
Very informative video. I'm in the market for a mini lathe and like to know what I'm getting into.
thanks much!
Great video. Thanks for sharing. I have a question about the angular ball bearings. You talk about 7206 model (single row bearings), but you display 3206 model (double row bearings). Which ones do you say are the optimal? Also 7206 are 16mm width, 0.8mm smaller than the stock ones, and 3206 are 23+mm wide, so would they actually fit properly?
I wanna upgrade to 3/8 tooling and I was thinking of cutting the tool post down on the bottom but if I did your solid tool post and don’t use the crosslide for tapers then I can just make it a little shorter and get more rigidity at the same time as being able to have 3/8 tooling thank you a bunch this would be cheaper and better in my opinion
Thx for the vid! Helps me a lot.
Would you say your sherline is better in terms of rigidity than this import?
notha channel ya like ta watch over and over. filmography excellent. Think id rather have the clap than change those bearings.
Your video is so professional bro.. Keep going forward mate 👍
This is very well done, some time effort and skill has taken the accuracy of that machine much higher
Thank you for taking the time to identify the potential improvements and editing the video
Nice upgrades. Do you know what you wound up with for a finished height on your replacement aluminum block?
I have been considering such an upgrade for a very long time and a height dimension would be a great short cut.
It wound up being 40.2mm as a finished height. Just the height of the compound and top slide and that should be easy to measure. Cheers
@@artisanmakes Thanks for replying to my query!
Weight always adds to rigidity, use steel instead of aluminium. Great video.
You can get seals made specifically for tapered bearings or you can make them yourself out of EPDM rubber!
Get yourself some 1 flute “o flute” cutters if you do a lot of dry aluminium machining
Hello friend, what difference did you have after you changed the bearing?
Very Nice! Did you notice temperature increase on headstock after change bearings? Thanks a lot
No heat that I can notice. Too much heat means too much preload. Cheers
Can you remove the clear film from the front plate?
Great video. What is Your procedure for periodic greasing ? Do You take apart the entire gearbox or do You grease them from the outside, taking of plastic bearing covers only ?
For the bearings I take it apart fully to grease them. Although I only did it once a year
Do most of the mini-lathes take the same size headstock bearings? 30206 tapered roller bearings or the 7206B-2RS sealed angular contact bearings. Are the angular bearings double bearings or single bearing style?
Most mini lathes that I have seen in this 7 X 14 category take the same 6206 bearings. Like I mentioned in the video, 7206 double row bearings would be preferred but they are more expensive than single row. Hence the high cost I was talking about. Cheers
To get the correct preload for the tapered roller or angular contact bearings without breaking anything, assemble and tighten the adjusting nut slightly and run the lathe for a 1/2 hour..........if the bearing housing is cold the preload is insufficient but if it's starting to get hot after 10 minutes it's too much........slacken or tighten the adjusting nut until you get the bearings to run just warm.......no more......the grade of grease will determine what temp the bearings run at.
I did the angular contact mod earlier in the year and got both bearings for less than £30 from Arc Euro Trade if memory serves correctly
That could be right. The set I was looking for specifically were pricy due to the high tolerances and double row of bearings which might be a little overkill for this lathe. Cheers
Looked like most of that chuck play was in the mounting or frame
2:55 7206 RS angular's are over $200 each on McMaster
Superb video. Is the spacer original one from the lathe or you have made it?
Yes the spacer is the original one from the lathe.
How many of you are coming from ToT? ;)
I bought a pair of angular contact wheel bearings 35x62x40 for 30€ but havn't installed them yet. I thought a combined spindle/bearing contact of 80mm would be really good. What do you think about this arrangement?
Hi, I also want to make the bearing adjustment. I want to do it with the 7206 bearings. Can someone tel me what the setup is? X O or in the same direction?
At what point does it make sense to get a better lathe versus modifying and having to make compromises like eliminating the compound feed?
Depends mostly on space and budget constraints. I have a small workshop and it is a hobby for me. I can upgrade the lathe and sink time into it and get the most out of what this machine is capable of. However if I had the space and budget I think it is always best to get the biggest lathe you can get. Cheers
Very good hello
Like for GIB making part.
Hello. I’m say first. Great 👍🏻 videos. And looking at venvor. 8-1/2 x23 or 29”. Has 1.5” spindle bore. Around 1200$.
But I seen one same brand big motor 1100w dc. All same but 16” and lot accessories 4jaw steady and follow rest. Mike and caliber and tooling metal gears ⚙️ lot extras. Same price around 1150-1200$ us. What u think. Might like try make gun barrels mostly around 16” biggest be upper 20s. It does hav 1.5” through spindle I don’t think ever have barrels that big circumference my bull barrels are .90. There big. My Remington 45 bp not 1.5. Lol. Idk. Get longer 23 or 29” or more accessories I have little first edition db/200 looks brand new with milling accessories so have little lathe/mill and proxxon m70 mill table.
Even thinking on selling it there commanding top dollar in new shape. Lol. Too much I think but glad I didn’t give whole lot but decent price for condition like new. And wooden box. But idk think I be sad if sold the little bugger. But on bigger lathe what u think.
Now watching ur video using the sherline to fix parts on bigger one. Makes me want keep unimat even more. Lol plus it’s only milling option besides a drill press what a drill press lol. Thanks for your help.
From ur ole hillbilly buddy stay safe.
Dude, how do you part the superglued metal strips later. Is easy to do it? Thanks. Regards.
I usually use acetone to dissolve it or a bit of heat from a butane torch and some heat proof gloves
Thank you! Regards@@artisanmakes
There are many mini lathes that are nothing but expensive toys !
What about alignment after replacing the bearings, or is that not necessary?
As long as the bearings are properly seated they should be aligned just fine
I've been thinking about buying a lathe to educate myself on for a number of years, but eventually I'm burned out by the huge amount of options open to beginning machinists and hobbyists. I already own a ridiculous amount of tools and shop equipment and have used it mostly for building 4x4 pickups, small block GM engines, and projects involving the three boats I had at one time.
Instead of just diving into a new hobby and possibly throwing money away I'm wondering if anyone can recommend a good starting point for an entry level lathe, milling machine, CNC versions of both with small parts in mind, up to and including the size of 80% receivers, largest being the AR10. They can be purchased in the AR15, 10/22, P320, 1911, and various striker fired pistol platforms. Suggestions?
Grizzly is a great place for equipment. Their products usually come with more bells and whistles than other dealers, at no extra charge. It is also easier to get parts and support since they are based in the US.
I got the green bear flavor of this lathe, took too deep of a cut and broke all the plastic gears inside the head. Worse idea ever... I have a set of metal lathe gears and i 3d printed a set i can use to cast new ones. How did you mitigate the load on your plastic gears to keep them from snapping teeth?
I swapped out the motor a while back to a 400w AC motor. It spins a belt and pulley that is mounted to the rear end of the spindle, so I don't have to go through the gearbox. Cheers
Good video. But how are you gonna work on that spacer without taking it appart 😅
With the stock bearings, machining the POM spacer should be fine to do. The stock bearings are fixed into place pretty tightly and should stand up to a bit of light machining. Cheers
@@artisanmakes but dont you have to take it appart to get the spacer out?
Any thoughts of doing the gib strip without a mill? Mines horrible and sloppy
Get stock material the correct thickness and file to shape?
how do you adjust your depth of cut?? The carriage only moves back and forth not in and out.
I didn’t think this through. You can adjust depth of cut with carriage.
Yes, the cross slide does that.
Please, don't you have exact dimensions for the gib strip replacement as seen from 5:20? I assume that angle is 60°, but what about width and thickness? That would be very helpful :)
Just match it to the dimensions on your existing gibs. They can vary between machine models. They generally are 60 degrees but the widths can change somewhat
@@artisanmakes Yeah, it makes sense. Thank you :)
What kind metal are you turning in the test footage?
I can't remember off the top of my head on the grade bit I am pretty sure it is 1018 hot rolled steel.
@@artisanmakes thanks
Couple of oil seals and packing the bearings would work out better at keeping out the chips and long life
Nice work though
This press has worked like a charm for my projects ua-cam.com/users/postUgkxajoEbapTfqWaadnqb04h6U576yxXp-FE . I didn't even secure it to my table top, mainly due to the fact that I was using a 15 lbs drill vise. It's not flimsy at all as to what others have claimed it to be. Make sure the locking nuts and levers are secured and there won't be any issues with light pressure and patience. I was able to drill through aluminum, plastic, and steel (steel took a while) with no problems at all. Yeah it took a little longer than a regular drill press, but I don't have the space OR the money for one.The instruction manual was worthless, but luckily assembling the press was intuitive. However, the manual would be good for ordering replacement parts if needed. There is a nice breakdown of the parts that are included in the kit. Before ordering, make sure it is compatible with your unit, it is clearly stated what models the press is compatible with.This was an excellent purchase for $40!!
Hi, another problem is tool moves away from work when facing off the end. No saddle lock!!
Thanks for the suggestion. This is a feature that these lathes lack from the factory. Thankfully I made one a while back and it really improves the cuts the lathe makes. cheers
A built in saddle lock is disconnect the feed screw and then use the half nut as a lock by moving the cutter into position and set the half nut. It acts as a lock perfectly. I use it for all my work on the same model lathe.
@@shedmanx3640 yes have used that method also. I made a clamp on saddle saves any diconnecting.
How to upgrade mini lathe:
Step 1 - have a horizontal mill :D
For some of these a mill is necessary, believe me when I say I have tried to make these mods using only the lathe with little success
⭐🙂👍
Zor
5:18 My word for today is "gib strips".
Meanwhile the headstock on mine came with stripped thread and wobbles around...
A tap and die set will fix that in just a few minutes.
You want the gibs to wear our not the bed or ways. So making a gib out of brass would only wear out you lathe quicker. That is because the softer material will accumulate abrasive particles and act as sand paper. Why do you think on all machines, new or old, the gibs were made from hardened steel?
Thanks for the feedback but I have to disagree. The cast gibs that it came with have worn the dovetails a fair bit so replacing was a must. Brass is absolutely fine. It is a very common upgrade and I have not heard of people having issues. The slides get cleaned frequently so I wouldn't worry about brass accumulation. If the cross slide was hardened I would opt for a steel gib, but here it won't be an issue. Cheers
How much
get a set of vblocks for the mill
Certainly looking to do so when the workshop budget allows for it. I'll probably be needing it soon for when I start to machine bigger round stock. Cheers.
The most of rigidity loss comes from a void under the headstock.
Absolutely. I thought the same and installed a piece of metal in that void to increase rigidity and it makes a big difference when parting steel. Cheers
@@artisanmakes you can watch this video ua-cam.com/video/YuRGxuMk9Ww/v-deo.html (it's a series of video) of this highly technically skilled man about this problem. It's only in Russian but auto subs does ~90% correct job.
There are more excellent videos about mini lathe upgradeupgrade on his channel.
It would also help if you bolt the lathe down to a more secure table. Ideally something made of steel or iron and perfectly flat with the ability to adjust and lock down level.
Yeah ideally I would love to do that. Not sure how much of an improvement it would be, but that would be the optimal solution. Cheers
SIR, HOW MUCH THAT MINI LATHE MACHINE.
reg. milling the toolpost: You don't know a flycutter in down under? ;o)
Thanks for the suggestion. I've only had my mill for about 3 weeks now, so tooling is pretty limited and still in shipment. Cheers
now, make it CNC 😏
Thanks for the suggestion, but I already have a CNC lathe (the sherline 4410). I've worked with a lot of CNC mills and lathes and I'll probably stick to manual machining on this one for the time being. Cheers
I don't understand why you would advise to "lightly" rub a little grease on those bearings, when they are meant to be packed? What are you trying to do with that technique? 🤔 I think I disagree.
No, for lathe headstock bearings it is not advised to pack them with large quantities of grease. This is inline with the literature I have read on this subject for lathes of this size and in line with what I have seen other people do on lathes of this size and with much larger lathes. Of course if you want to pack it tightly on your lathe you want/if it is advised for your lathe.
Want some brass?
It would be nice if a guy didnt need a milling machine to do most of these upgrades, as I dont have one. They do look good though, except I dont consider eliminating the top feed an "upgrade".
Pick and choose what suits you and what best suits you and your machinery. Unfortunately some.kf these do require a mill. And for a lot of people, a solid.tool post is a big upgrade for the lathe
@@artisanmakes Yep, not complaining, I wish I had a mill. I do appreciate your videos too. Some of the issues you fixed are a real problem. I hope I can find ways to fix them with what I've got. Thank you.
Still using those nylon gears😢
A mix of acetal and aluminium gears. For the scope of the work the mini lathe is expected to do they do a good job. Cheers
Tip: *Never* us copper based grease with roller bearings!. The odds are that one or more of the rollers will 'slip' and therefore wear a flat on one 'side'. That's sudden death for the bearing.
Hi mate, this is lithium grease not copper based and its the stuff recommended by the bering manufacturer. The a quick look at the MSDS shows it doesn't have. Any copper in it. Cheers
@@artisanmakes I never implied that the grease you used is copper based, just that others may be tempted to use it. As much as it seems to be a good alternative, it's not!
@@amanofmanyparts9120 Thanks for the response. My bad, I misunderstood your comment. Cheers
Ten minutes in the kitchen with the freezer and the oven would give you the 200 degree temperature gradient for easy assembly of the bearings.
Stavros
Thanks for the tip. First time doing lathe bearings so I'll be able to remember the next time I have to do this. Cheers
Hello
Hey you didn’t apply the grease the correct way
Everything is a lot more difficult when you have tripod, mic and several studio lights in the way :) From memory I spent a long time doing it off camera
The correct way would be what? Put grease in palm, and press bearing into palm to force grease into bearing?
you dont pk bearing lk that
This is the advised way to pack bearing for lathe headstock bearings. For lathe headstock bearings it is not advised to pack them with large quantities of grease. This is inline with the literature I have read on this subject for lathes of this size and in line with what I have seen other people do on lathes of this size and with much larger lathes. Of course if you want to pack it tightly on your lathe you want/if it is advised for your lathe.
7206 bearings are $7-10 on aliexpress
Like I said in the video, $90 for the set I was after. Low run out, 2 row bearings that I'll probably end up getting in the future. Cheers
Antonmursid🙏🙏🙏🙏🙏🇲🇨