The CJ0618 Lathe Saddle Part One, Measure the Problem with Gauge Blocks and Banggood Tool Review
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- Опубліковано 22 чер 2024
- I recently bought a new Chinese CJ0618 7x12 Mini Lathe, very similar to the classic Sieg C2 lathe which is sold under different names all over the world. I have a few plans for this lathe, but the main reason for buying it was to finally answer all the questions I get asking whether the Proxxon PD 250/e is worth the money, or if a Chinese lathe is a better deal.
In this video I'm taking a look at one of the more major problems, the fit of the saddle, headstock, and tailstock to the bed. The parts seem to have been made very innacurately, and I need to measure just how bad the problem is. This is a great opportunity to try and and review a set of Gauge Blocks sent to me by Banggood for review. Once I've done these measurements I'll have a much better idea of how to go about repairing the machine, and improving its condition.
00:00 Introduction
00:50 Unboxing the Gauge Block Set
02:49 Preparing the Lathe
05:15 Measuring the Saddle gap
06:27 Gauge Blocks and Their Limitations
07:46 Measuring the Tail Stock
09:26 Outro
The links below will financially support this channel if you use them to buy stuff:
Banggood Gauge Block Set 32 Pc - bit.ly/3YiKQb0
Machines:
CJ0618 7x12 Lathe - ebay.us/d7ZXd7
The Gauge Block set was sent to me for free, to do want I want with, as long as I reviewed them.
Edited with:
kdenlive 20.08
audacity 2.3.3
Music:
Easy Lemon by Kevin MacLeod is licensed under a Creative Commons Attribution license (creativecommons.org/licenses/...)
Source: incompetech.com/music/royalty...
Artist: incompetech.com/ - Наука та технологія
For less than one millimeter feeler gauges can come in handy.
They are a much under used resource in the shop. I buy sets for cannibalizing when ever I can from yard sales.
@@ExtantFrodo2 the non tapered ones, if cheap make great shims for almost anything.
Ah the joys of trying to find a hobbyist lathe. Either you get a 70+ year old western machine so worn out it has tolerances you can drive a truck through and costs as much as a new import. Or you can get a new Chinese machine with tolerances you can drive a truck through from the factory 😭
Sad but true.
Unless you are so lucky to get a western machine barely used I have to agree with you 100% :-)
That’s why the Proxxon lathe is a very good alternative. They also make a bigger version than the one on this channel.
@@Wasper216 I do kinda wish I'd bought the PD400 when I was starting out, though when I do upgrade I think I'll be going for something a bit bigger.
If a Taig or a Sherline will do, those are still made and available new.
I have never seen a lathe that bad the manufacturer should be ashamed I enjoy your videos you always provide a solution to a problem and that really helps out the mini lathe community I have a Chester conquest mini lathe and have done a number of upgrades to it thanks for sharing your mini lathe journey looking forward to more upgrades stay safe and healthy all the best god bless
The quality and conciseness of your videos is truly fascinating. It really is a joy to learn from you Sir. Keep up the good work!
I’m not sure what it is but getting a notification from this channel just makes me smile for a different reason then others. By far my favourite stuff to watch keep it up
Thanks! You've made me smile too. :)
Agree - I just wish they happened a little more often.
They are always worth the wait though.
@@jeffarmstrong1308 I wish I could produce them faster too, but life has been complicated. I'll keep making them as fast as I can, as long as people keep watching them.
@@AdventureswithaVerySmallLathe Oh we will. No worries!
Thanks for sharing - thinking of trying one of these machines and your content is great
Nice video about a sad lathe. You can measure down to the minimum increment of your gage blocks on the surface plate by stacking blocks on both sides of the object. You put say a 1mm block on one side and a 1.01mm block on the other side to get a height difference of 0.01mm. The problem here is the prismatic ways where you need a precision replacement for that part of the ways on a surface plate.
Sadly I have no surface plate yet. Nowhere to store or set up something big and heavy.
Adventures with a Very Small Lathe Well a machine table then-the flattest thing you have. Actually I wonder if you have seen the granite indicator stands for inspection with a roughly 10x10cm surface plate and a post to hold an indicator-that might fit your very small world.
I have the same model lathe, and it has the same problem, I measured it with feeler gauges to a little over 1.6mm, a piece of 1. 6mm brass sheet epoxied to the saddle was my fix. I also hand scraped the brass to fit the ways of the lathe bed once the glue had set. I haven't done much work with it since the repair, but it seems to work alright so far.
Nice! Thanks for letting me know that approach works. I'm discinclined to use brass, though it would be easier to work with.
Hi Alistair,
Nice to see a video from you... and a enjoyable one too...
Looking forward to seeing this project progress.
Take care
Paul,,
Thanks Paul! I've been really enjoying your Unimat SL disassembly. Keep up the good work!
@@AdventureswithaVerySmallLathe Thank you.
Ooooh! Did someone just say "Unimat SL"???
If you treat the off-shore machines as a kit that must be assembled to the tolerance required by the end user, and keep an open mind, and try not to lose it over the lack of quality, you can get a decent unit with some effort. It can also be a good way of learning new skills in scraping and setup.
Rotary SMP has a great series called "polishing a turd" that is a must watch for all with a mini lathe.
Cheers
Rotary SMP is doing a far better job than I ever think I'll be able to with mine. I didn't find him until after I'd started, but he's been a great inspiration.
I believe that MythBusters actually did polish a turd :)
so takes me back to my apprenticeship days ,,i need these
At 1.8mm (70 thou!) you have your work cut out for yourself. It's obvious that the saddle groove is not nearly close to fitting the way slide and that the surfaces were cut with rock and chisel. Personally I started by using an 5 tenths DTI on the ways and put marks and readings about every inch with particular attention to the way slide. Then to the saddle grooves and slides and on to the compound. Luckily I have an 18x24x3 surface plate to reference from. TOT's early surface grinder restoration videos have some really helpful tips and tricks to the metrology of this kind of work. Working in 3 dimensions is a bit daunting sometimes. Thanks for the tip on the gauge blocks and surprised by the Grade 0/1. I found denatured alcohol works good with a lint free cloth. Thanks for sharing your findings! Stay safe and healthy!
Excellent and informative
Thanks Simon! I haven't seen any Proxxon lathe videos from you in a while. How are you getting on?
I'm not a machinest at all but I love watching your video's - even if it is dealing with this half precision boat anchor. Very well described as well.
Epoxy a piece of cast iron onto the carriage, mill to approximate thickness and then finish with a scraper. A non vented brake disc from a small car might provide a useful source of material, they are cheap to buy new and already have very flat finished surfaces.
I agree with others that the bed V is very likely the root of your problems, but, like you, I wouldn't have the facilities to correct that so whatever works is the way to go here. On the plus side it would be very difficult to make this lathe any worse than it already is!
Thanks for sharing!
Can't wait to see more. Btw feeler gauges can hel you get closer in the ballpark
ToT got me to subscribe 😬 good information and explanations
Thanks for sharing this with us, it is at once inspiring and daunting. I think that you have cured my desire to own a small lathe, lol
The trick is to buy from Grizzly, Little Machine Shop, Micro Mark, or even the Harbor Freight 7 x 12 model (online only, not in stores). They still require tweaking, but nothing like these cheap no name units! Look up Frank Hoose’s mini lathe comparison vid on UA-cam. Any of the units on his comparison chart are of better quality than the ultra cheap ones, but you pay for that quality! I’ve got a Grizzly G0765 7x14 lathe and a Harbor Freight 7x12 lathe, and they’re pretty good machines! Grizzly machine is a little more feature loaded, but I actually think I like the HF unit a little better! I machine steel and aluminum.
You can get hung up on the issues like the one covered here but you need to consider what work are you going to do where these will actually impinge on the finished item. In this case there is a minor issue with the effect of the tool height with radius but so long as you know the angular error of the cross-slide to the horizontal you can compensate for this using the old clamped steel rule technique by adjusting the tool height till the rule is perpendicular to the cross slide rather than vertical. I have used a Clarke lathe that has this issue for over 20 years but have never found this or indeed the other issues with the machine stop me from producing work to the required accuracy including bearing fits etc.
Excellent video, thank you for showing this technique.
Now I am afraid to go measure mine though because I know mine is going to be way out just by looking at yours and remembering what mine looked like when I upgraded the saddle.
This is going to be a large can of worms so now I am really looking forward to your next videos.
Don't worry too much about making the slide level. The thing to focus on is making sure the V groove in the saddle fits snugly onto the bevel on the bed. It just happens that on my lathe I need to make the slide level in order to get the bevel to fit.
@@AdventureswithaVerySmallLathe when are you going to post part two?
YES ! Please ! How did you level the saddle?
Love the This Old Tony trick
It just felt awkward if you ask me :/ If I want TOT I watch TOT. This guy is so far from TOT that any attempt of this kind makes me cringe.
@@ScinnerNo1 It was a lot better than watching him clean a hundred gauge blocks :P
The Cross slide ways don't actually have to be co planar with the bed for general turning when the compound is static as the tool height is set at in relation with the true centerline. it however becomes problematic when the compound traverses as it causes the tool height to raise or lower in either direction depending on the angular orientation. with this in mind if you later intend to go the solid toolpost route you shouldnt worry about getting it perfect, coverage PPI and a middle 30% relief is more important. I have half a roll of 1mm Turcite left and a small strip of 3mm Turcite that would be more than long enough, I can pass either cut to size along to Emma and you can work something out with her if that works. you will also need to work on saddle to apron alignment in relation with the rack and leadscrew, same goes for the tailstock but there are some nifty tricks you can use depending on how far you want to go with it.
I remember a Keith rucker video of his big lathe restoration and he used special stuff on the ways that can be scraped in.
But I think it's to big of a gap to fill with that stuff but still a good series to watch and see how to measure everything.
Be aware how you fill it, steel on steel is going to be an issue, steel on cast iron does work but what ever you do scrape it in properly to get the best accuracy.
That sounds like Turcite perhaps? I think that would be overkill for this lathe, it's just a practice piece, and not fundamentally of good enough quality to invest in the expensive stuff.
I've always used kerosene to clean stuff up, but I've switched to a proper degreaser from an automotive store. It smells waaay better (probably no worse than fly spray), and seems to work just as well
Good video
Thanks Tom! Do you know what the solvent ingredient in that degreaser is? When I did my first internship, workshops always had a bottle of 1,1,1-Trichloroethane, but it was phased out after the Montreal Protocol. Great degreaser, but terrible for the ozone layer.
Any effective degreaser that is not a Montreal protocol problem will be flammable (Flash point 65C).
I find petrol just as good as anything for the initial gross cleanup with a good quality solvent (think paint thinners) that flashes off quickly to remove any final residues. If you can get it at a reasonable price, a pure naphtha solvent is best but watch it around ignition sources. It’s not the solvent of choice for lighter fluid for nothing!
@@jeffarmstrong1308 Thanks for the info. I hadn't realised how non-combustible 1,1,1 is until I looked it up just now. No wonder it was so popular. White spirit (the UK name for mineral spirits) can be pretty effective, but it tends to disappear pretty fast due to brush cleaning and paint thinning. The big bottle of kerosene is unlikely to ever run out though.
Acetone, or 99.99% isopropyl alcohol works for me.
Thanks for sharing...
you are a genius nasa was looking for uou 😂🎉 , so proud of your knowledge and expertise 😊
Великолепное видео. Спасибо!
Bless You!
Really nice your video ending with the puppets working the pieces. I did not think
That there could be a tolerance of those dimensions even if more than a tolerance it seems a measurement error !!
Thanks for sharing
LEGOS!!
I spotted the bare fingers/hands too and was reminded of a diagram that I used back in the 70's to explain to customers why they should NEVER, EVER touch the surface of an exchangeable computer disk pack.
This link below shows a modern disk head "flying" height - yes, that's right, disk heads today, just like back in the early 70's FLY! They MUST NOT touch the disk or ... !!! ... which is where the expression "head crash" derives. And a bad head crash can turn a disk drive into a lathe VERY quickly and spectacularly!
Hopefully the image says it all but, ignoring the effects of skin acids which deteriorate the surface dramatically, it shows that a fingerprint is around 10 microns high or 0.01mm!!!
BTW back in the 70's & 80's when disk drives were the size of large washing machines and twice as heavy, the analogy was that a disk head flying over the disk surface was equivalent to a 747 flying at normal cruise speed (500-600 mph) at a height of 6 inches above the ground!
With todays smaller and faster disk drives (15k rpm v 2900 rpm) that's more like flying an SR71 Blackbird or Concorde at Mach 2 to Mach 3, just TWO inches above the ground!! 😲😲😲😫😫
That alone can blow your precision clean out of the water! Here's the link to the image:
acsdata.com/wp-content/uploads/hard-drive-flying-height.png
to add or to remove , won't the height of the centre of the tailstock suggest the path of lease effort/most accuracy ?
Wow, that is a massive error, but on the other hand , the challenge is quite intriguing as long as time is not an object . It should prove very interesting from our view. Cheers and good luck!
we love you too
Great! Now I have to go see how bad my Central Machine lathe is. I have seen someone mill the v- groove but who has a mill to do that. Correct the tailstock and then you have to recenter it probably with more shims or machining. Oh well. Facing I end on center but probably start high or low right?
You could use filled epoxy as "shims".
Stefan Gotteswinter has a video about tramming his mill using this product.
I loved watching that video; really informative. I think the gap I need to fill here is too large though. Thanks for reminding me it's out there.
@@AdventureswithaVerySmallLathe One alternative could be to glue in Turcite or similar material and then adjust it right thickness. Keith Rucker, WintageMachinery dot org has couple nice videos on lather restoring. Episodes 16 and 17 seem most relevant. Monarch Lathe Restoration - Part 16: Grinding and putting Turcite on a Cross Slide ua-cam.com/video/olpSKiQRrWo/v-deo.html
I really love your videos and look forward to each new one
I have the same chinese lathe i must been so lucky as it was pretty good out of the box although i have been improving it as i go along
I hope you didn't pay much for yours...did you mention it was one from a QA rejected batch ?
I didn't pay much for it, but the idea that it was from a QA reject batch is just a theory. It was unbranded, sold from an anonymous Chinese ebay seller, and shipped from a warehouse in the Czech republic. Trully the bottom end of the market.
Wow, that's quite the gap when level! I wonder the same thing as Reman1975 below, as it seems like stuff from that particular country is really hit and miss when it comes to decent tools or not.
I'm pretty sure this lathe was thrown together from QA reject parts, after the better models were sent off to the name-brand distributors. It's a disaster machine, but that makes for more interesting videos.
@@AdventureswithaVerySmallLathe Lol, basically "an assembly of castings, some assembly, fitting, and swearing required . . ." Thing is that by the time you're done with properly fitting and repairing the pieces you'll have a machine better than the "top shelf" version of these coming from there.
@@EverettsWorkshop That's the plan, fingers crossed. :)
i need to practice more whit the old Tony tricks last time i try one i ended in other floor
This Old Tony's techniques don't come easily or cheap. They require dedicated, training, and practice.
@@AdventureswithaVerySmallLathe agree
Your best bet for shimming up your saddle and tail stock is to make up the difference with a shim of a similar material (mild steel in this case should work) and using countersunk head screws to mount it to the cast pieces.
I'm considering fixing the shims using a metal epoxy, like J-B Weld. These shims would only ever be under compression, so they don't need any shear strength.
@@AdventureswithaVerySmallLathe That would also work pretty well. I was going to recommend Loctite 603 or similar for that application, but epoxy is miles cheaper and the rough milled surface of the cast parts would be great for epoxy.
I may be a little late to the party here but the issue doesn't look like the back part of the carriage there. It looks like the internal dimensions of the cuts to ride on the triangular way. they are too small and don't allow it to sit all the way down on the ways of the bed. Both the tail stop and carriage appear to have the same issue.
You're absolutely right that the problem is at the front of the carriage, but I don't think the problem is that the grooves in all three parts is too small. There just isn't enough material in the castings to cut them any deeper and still have good strength. I'm fairly sure the problem is that the bevel on the front of the bed is too high. Unfortunately machining or grinding the bevel down is completely outside my capabilities with the equipment available, so I have to find another solution.
No more TOT references, please. I'm content with you being you!
I like video's verry much!!!! When do you show the community how you fixed the crosslide fault from 2.61 mm. Further how did you align de headstock to the ways?
I'm working on it, but it's a really long video that's going to take a while to edit. The good news is that I captured a lot of detail during the learning process.
@@AdventureswithaVerySmallLathe That's great to hear. Thanks for addressing comments in older videos. Im facing the same problems as you are. I will wait for the video until i make my final decision as to how to tackle this.
I appreciate the effort you extended to your lathe, but frankly, the more videos I see on these lathes from the PRC the more I am thankful for my SHERLINE. Its American made and never had ANY of the issues I have seen here. I'm not sure what price point would ever make having to address all these headaches worthwhile. Just sayin......
How well does the cross slide gear mesh with the gear in the apron, and is it well-centered to the drive screw? That should tell you whether to add to the rear or subtract from the front. I wouldn’t be too hesitant to widen the V-notch since you aren’t likely to worsen the accuracy of the machine. I bet you can square just one of the two v surfaces up to an end mill and buzz it off with the mini mill.
If you get it close you can lap the V-groove by sticking lapping film directly onto the opposing ways. Lapping film is just adhesive-backed sandpaper without the paper, and it does a great job of temporarily making a mating surface into a custom formed sanding tool.
I don't think I'd be able to do a good job of re-machining the V-notch correctly, which is the main reason I've been focused on the idea of shimming the back. My milling machine is just too small to work with a part that large. There is a fair amount of slop under the Apron, and I'm pretty sure I'll have to do a bunch of adjustment to the gear and lead screw half nut however this project goes.
Once I have the saddle close, I'm going to try my hand at a bit of scraping, which should make an entertaining disaster video.
A question is how much the tail stock is going to be too high from bringing the rear up. It’s rotating it around the front bed rail. Side to side can be adjusted by the side adjustment of the tail stock assuming there is one. But the height will have to adjusted by removing metal between the top and bottom tailstock parts. Secondly, it can be assumed that the saddle and tail stock front and rear rail slides have been milled at the same time in a horizontal mill. In that case, rotating those parts by lifting the rear will cock the front “V” so that it will no longer fit the bed properly (assuming it ever did, that is), resulting in significantly increased wear and less support.
Let me answer the second question first:
The idea of this fix is to improve the fit between the front "V" and the bevel on the bed, not make it worse. The fit is currently really bad, scraping against a single edge rather than making good face contact. Part of what I'm doing in this video is trying to work out where the saddle and tailstock need to be to fit the bevel correctly, though it's hard to determine. I'm expecting that I'll have to re-work the V grooves towards the end of this process, probably by scraping them to fit the bevel.
It should be noted that the headstock has the same problem, as when all is fixed, all three parts will have moved, and you're absolutely correct that the tailstock will no longer line up with the spindle. I can't be entirely certain how much, but I think it's very iikely the tailstock will be too high, which will mean I can fix it by removing material.
@@AdventureswithaVerySmallLathe from what I see in your video, the mismatch with the headstock and rails is worse than that for the saddle and tailstock. In fact, the more I think about it, that difference could actually result in the tailstock ending up lower, not higher. Do you think the change in the saddle height will give a problem with the lead screw? The rear of the screw is adjustable as you showed, but because of gear engagement, I doubt there’s much to be done at the headstock. The close to 2mm is a lot.
Here is what I would do. Drill and tap two holes on either side of the saddle ( Or remove and enlarge those oiler ports ) Add a bronze bar underneath. Use grubscrews to set the height pushing against the bronze bar.
Someone used to do an upgrade longer bed for these 16 inch long i think 🤔, be interesting to get a measurement of the v from each
I've found a couple of places selling an upgraded bed for the C2, but past experience of buying C2 lathe accessories is that the CJ0618 is slightly different in small ways which mean C2 accessories don't quite fit. Probably not worth buying a bed just for curiosity's sake though. :)
@@AdventureswithaVerySmallLathe Yeah, the CJ0618 seems to be somewhat off in every way. It's a slightly different set of parts nearly everywhere. My spare Grizzly saddle fits the CJ0618 bed even worse, so I think that's a good indicator that another bed probably wouldn't work any better. I think the issue is the V-way, but I don't see how I could successfully deal with that.
I was wondering if you might use Turcite Slydway on the tailstock or saddle. It's available in 20mm wide strips, 1.5mm or 2.5mm thick but seems to be pretty expensive. I found 90 euro for a strip 2m long from reiff-tpshop.de! But it can be scraped.
I think Turcite would be overkill for this lathe, but I'd definitely like to try it in future. This lathe is more of a practice and learning piece.
The lego-man most funny that I have seen on channel lice this)
You can usually adjust micrometers. There's bits you can fiddle with inside the handle.
Sounds like the old watchmaker thing. “There’s only two kinds of people who can take a watch apart: A watchmaker, and a damn fool”, Ha!
@@tomt9543 I never found it particularly hard to do. They even give you the tools to do it with and standards. So they expect the end user to do it. Least that's now my 0-4" mic set came.
@@1pcfred my vision is so bad after 45 years of welding that precision measuring for me is using an adjustable wrench and a tape measure in place of a micrometer! Ha! I’ve actually got a new set of micrometers, but I’ve never paid attention to what else is in the case! Thanks for sharing this! Sounds like a good project for one of these crappy winter North Carolina days!
@@tomt9543 if your eyes are bad then use a lot of optics to improve your vision. Reading glasses and a magnifying visor at the same time works for me.
@@1pcfred That’s what I’ve been using for probably 10 years! This old age thing is tough! I’ve got chuck jaw marks on my visor! Ha!
Can you mill out the v in the headstock and saddle to bring them in line with the flat section at the back ,seems thats where the fault may lie 🤔
Perhaps check the vertical tailstock allighnment with the headstock to see if the headstock is high
@@darynradcliffe2909 Not with my current mill, or any that I could fit into my current small shop.
Is there a video on how you fixed this problem? I cant seem to find it
I'm working on it. It's a long, complicated video, and there are a couple ahead of it in the queue.
If you want your Gauge Blocks to last, wear cotton or rubber gloves. Never handle with bare hands, the salt from your hands will ruin the slip faces. Failing that, purchase ceramic blocks.
Noted, thanks!
Just checking to see if someone had made this point - we'd be shot for handling them with bare hands! They need to be *really* clean, too - none of those grease smears on the ends.
@Phillip Dittmer ceramic is what was used (still is) for disk drive heads and they too are impacted by skin acids so moral is ALWAYS wear protective gloves and clean the blocks used after EVERY use with lint free cloth and acetone!
I imagine you have seen it by now, but if not.... I believe it was Quinn over at Blondie Hacks fixed her motor mount with a very nice fix. She also had a clunky loose motor that was free floating. You may want to search for it, sorry I don't have a link for you. Love your vids.
What are the chances a Mathews or Grizzly mini lathe will not have these issues, I wonder. 10 mins after recieving a new Vevor 7x14 I had to work on it, the more i looked the more I found wrong that will put it out of commision sooner than later. It is going back to the store. I like the price, but not the quality. Are any of the $3000 mini lathes worth buying?
Hi , greetings from Italy. Dear, where can i find the second part of this job? am i so blind? very good video and great skills
I'm working on it. I'm currently moving house, so don't have my workshop and tools. I just have the tiny Unimat to tinker with.
@@AdventureswithaVerySmallLathe ciao, and thanks for answering me. jesus moving a house. really no envy at the moment. ;-) glad that i am not blind then . take.your time and will wait. great videos indeed
You can adjust that micrometer.
Hello, In the box from the micrometer there is normaly a smal key. You turn the micrometer til zero and look how it fit with the zero line. But before that you have to clean the micrometer take a pise of paper turn to zero and to pull out the paper. Then the micrometer is clean and now you can turn to zero. if not you must put the key in the smal hole en turn the key till the zero line is in line. now you can control the micrometer with a block when it gifes the same result then it is oke 🙂👍👍
Thanks for the tip! The procedure I followed on the older micrometer was the full teardown, service and reassembly that doubleboost showed on his channel. I hadn't realised there was a much simpler way to make small adjustments to the zero. My micrometer is now zeroed for the current temperature of my shop, and the gauge blocks are reading bang on!
@@AdventureswithaVerySmallLathe So the gauge blocks were bang on, that's good.
I believe you are not using your surface gage correctly. The post can be raised so that you can tilt down more. Leaving the post extended as you showed in your video pretty much locks it perpendicular to the surface when you push it all the way back, but the capability is there to rotate the post all the way to beyond parallel with your surface. This way you can still use your DTI for your critical measurements. Also not surprised some of your gage blocks are not ringing out. Bangood is a good source of cheap machine tools, but nowhere near the quality of Starrett, Mitsutoyo, etc. I purchase a lot of my machine tools used from eBay and it is surprising how accurate the high quality tools are after years of use and what a reasonable price they sell at.
Yep, I learned how to do that shortly after shooting that clip, but there are other reasons which I switch to the flex arm dial indicator instead. I wanted to measure the vertical movement accurately and I needed a range of up to 3mm. The dial test indicator I had on the surface gauge only has a range of 0.8mm, and it's tricky to use for accurate measurement due to cosine error. The plunge style indicator isn't vulnerable to cosine error if set up properly, and is easier to align vertically on the flex arm.
12 years ago in the tool room I noticed the tool maker leaning on the lathe, later as I was turning a diameter, I got awful chatter marks, I adjusted the carriage gibs and found they maxed out, I used various thicknesses of shim stock to take up the slack, (.005") then I cut and bent an 'L' at the end with a drilled hole and fitted it under the wipers with some grease, problem solved! The tool maker? He was a little mad since I 'messed' with his machine, but if he had the time he would have done it. 'Big Bill' passed away 2 years later, RIP bro!
Can't get ennough of this , pls make longer video
Couldn't you use shim sheet or feeler gauges to increment your stack by the few microns needed even tho you done have the blocks
The most impressive part is that neither of the Lego minifig helmets are broken!
Also, a gage block set has been on my wishlist for a while, so I'll be using that link soon. Do you know if it ever expire?
I've had Mr. Red since I was a child, so I can't explain why his helmet is unbroken.
I don't think the link will ever expire, but Banggood change their products from time to time. I'm sure they'll always have something similar if you search for it.
I couldn't figure out why it everything on my lathe was so hard, and parting was impossible. Turns out it's because of this exact issue. I have about a 1.2 degree downward angle on the factory saddle. This is a little more than a 26ga sheet of brass. I have a spare saddle that I got for a similar model that's even more off. I haven't yet figured out how I'm going to deal with this.
Once I measured it in this video, I fixed cast iron shims in place using JBWeld, then scraped the slideways until they made good contact. The whole thing is so much more stable, and the video is in production. The next step will be firming up the hold-downs which grip the under side.
You really need to finish that edit and post it up!
@@PetesWorkshop I eventually just CA glued the brass shim to the saddle. Worked great. Instantly made the lathe 100% better. Before it was just a collection of poorly fitting lathe parts. Now it's a tool that can actually do something.
@@nelsonbrown1988 thank you. I did do a test with a bit of stainless steel but adhesion wasn’t great. I will try again with some shim material.
i want one of this lathes is small an practical for my that i dont make much use of a lathe
Hi only just watch the video be careful it may be the V is not deep enough check with blue see what happens, looking at video when lifted V looked not touching as it should be.
Steve
so what was the fix? If there is a video send the link.
The next steps are in a video called "Fixing the Tailstock fit .."
The bed needs to be leveled and bolted down to make this measurement accurately. The way you are doing it is not accounting for twist in the bed, i.e. the difference in height between the two ways of the bed. In fact the easier way to do this would be to place a precision level across the two ways of the bed then place the level on the way of the carriage and compare.
Thanks for a very interesting, but upsetting video.
Just measured on my lathe. Using the compund flat as a reference and then putting the angle cube on the tailstock, I've got 0.50 degrees tilt...
Time 03:55. Oops. Thats a lot. No surprice. I measured the surface of the back end of the compound versus saddle movement in order to use it as a reference.... Useless surface.... Millimeters of taper.
The saddle is maybe suffering from the same error as the tailstock.
However, this affects the centering of cut off tools, and facing turning. How does it affect "general turning"?
Just used a caliper, measuring verticaly from the cross slide surface down to the bed. 0.4 mm difference.....
I got the though that the flat surface, close to the raised, v-shaped ridge, is not good as a reference.
The saddle, and the tailstock rides on the V-shape and the opposite flat bed surface,
What do You think?
Don't be upset, the lathe is probably fine if it isn't one of the cheapest chinese lathes. Literally in other words, Det är jättefint om det är inte den billigaste svarv från China 🤣🤣
What I'm trying to tell is that the measurement method isn't accurate and the faces you measure from might not be even made that accurate to the rest of the machine anyway. If you can tell that it cuts true, should not be worth messing about for the normal lathe owner
@@MF175mp True. However eyeballing tells about odd things. What does a center to center, chuck versus tailstock say?
Have fun, turn things and as long as that works, don't worry.
The main problem for me isn't that the saddle is sloped. The problem is that the bevel machined into the underside of the saddle isn't fitting onto the bevel on the bed. The saddle is scraping along with 3 contact points, which mean that it isn't stable, and the bed will wear. I've focused on trying to make it level because that is the first step towards ensuring the bevel fits properly. If you want to check your lathe for this, blueing up the bed and checking to ensure the underside of the saddle is making good contact is probably the way to go.
@@AdventureswithaVerySmallLathe I got it. I hope the lathe will serve me, give me useful works as it is. Fighting issues like this feels as too much.
Taking the tailstock away, turning it up side down shows a sad story. Paint is the contacting surface..... Checking a new MT2 fitted chuck in the tailstock it horizontally points off by 0.2 mm at a distance of 140 mm. Maybe ok. Vertically? The work of tomorrow will tell
I'm totally staggered by the fit on your CJ0618. I have a Sieg SC2 from Axminster and it's nothing like as far off. Admittedly, it cost almost twice as much though. Yours is so far off, I'm surprised you didn't send it back. But I suppose it will make for some fun. BTW have you seen RotarySMP's series on pimping the minilathe? ua-cam.com/play/PLHRtJd1bD3IQU-A-CPBwys-tTM3wKMOGW.html
If I sent it back, I wouldn't have gotten to make this video series! I have watched a lot of RotarySMP's videos, though I'm well behind and need to catch up. Thanks!
It seems the v on the bed is too wide for the saddle and headstock
That's probably the problem, but that's not something I can fix. Or at least it would be more expensive to fix than I think this lathe is worth.
@@AdventureswithaVerySmallLathe Or...it's time for you to get a mill
@@AERuffy It would need to be a really big mill to be able to re-machine the bevel on the bed, but more importantly I'd also need a big surface grinder if the bed was going to be any use after I machined it.
It doesn't really matter if the saddle is slanted, as long as the fit would be good.
And the gauge blocks are total garbage if they have errors over one micron.
I'm no expert, but I would say yes. Reason being that any slant of the slideways would add or subtract to cutting tool relief angles. But on the other hand the whole tool would also be at the same angle so maybe this cancels it out. Hmm this requires some more thinking and maybe a diagram to figure out.
@@Ealen75 sure it cancels out, no question about it. Also the dimensional accuracy and everything is 100,0% the same
I touched on this in the video, but I didn't have time to go into much depth. My objective is to make sure the fit is good, but it feels as though the bevel has been machined so it is perpendicular to the slideways, so the bevel will fit correctly when the cross-slide is level. This means that making the cross-slide level will be the best starting point before I start scraping all the contact surfaces so they are a snug fit.
@@MF175mp If we were talking about inspection grade gauge blocks I'd agree, but we're talking about a cheap set from Banggood which i doubt anyone would ever use for inspection. In the workshop I'm never going to need anything more accurate than a couple of hundredths. I don't have any tools which are capable of reading to the nearest micron, but the micrometer I used in this video reads about 6 microns over at zero, so the fact that it seem to read the stack as about 6 microns over the correct size seems to point to the gauge blocks being as close to correct as I can measure.
Make a solid block too, like steve Jordan channel.
link broken to gage set
Even if they were utter rubbish, those guage blocks would still be kinda handy... I use old guage blocks as parallels on my very small lathe as I can't get real parallels small enough and my crappy old guage blocks were awfully cheap..... although I did have to pay more for mine than you paid for yours. ;)
adding a shim cause your tailstock to rise
Lol, the saddle misfit is hilarious! Damn chinesium!
Hello, im telling everybody. about a device R. steven lang showed on his channel.www.lasercenteredgefinder.com sells them. mine throws a .001 inch red dot, i put it on all my "x marks the spot's". i use "dark blue marking color" by dykem. its a closer to "true blue" and so causes less "backscatter" because it dont reflecrrt red. that is the biggest backscatter creater. backscatter makes the dot look bigger. not good. i think this tool is wanted by every machinist. poppy says stay safe also keep eating!!
Thanks Poppy, that looks really cool! A bit big for my mini-mill though, at 3 inches. Do you know if there are any distributors outside the USA?
@@AdventureswithaVerySmallLathe my mill is a sherline. i have little problem using my laser. dealers outside u.s.? amazon will sell you one. e-bay? hope this helps poppy
Are you kidding me on the surface gauge? Undo the side nut and slide the rod up further and it will rotate past 90 degrees
saddle mod: 6 studs, nuts, shims.. No saddle screws.
Instead of oil in hard to reach spaces like jibs, I use grease, it stays put and works for ages, ditto for lead screws where the flange is just back from the handle.
With the chinesium lathes must depend on the day your turd was assembled mine the head stock and carriage sets good on the tailstock leans like a drunkard and the center sets too high up. Hate to spend the big bucks for a hobby lathe but the proxxon looks beter all the time.
Weld & grind to the correct die
There ain't no welder in my shop. I'm a machinist.
The lathe came all out wack, so any improvement is way better that it was.
oh boy, those nails.
´not good gage blocks. the ringing is very weak
Thanks for sharing!