Mini Lathe Headstock Rigidity Upgrade
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- Опубликовано: 26 фев 2022
- G'day everyone,
This is a follow up to the lathe maintenance video from yesterday, as well as a follow up the the rigidity upgrade video from last year. I have spent the last year trying to get more performance from my mini lathe, and one way to do that was to increase the rigidity.
One area of the lathe which I have been overlooking is the area under the headstock mounting platform, where the motor used to be housed. The area has very little supporting material, yet it needs to support the headstock and the cutting forces. I decided that this was an area that needed to be upgraded.
Lathe: Sieg c3 7x14 Chinese Mini Metal Lathe
#minilathe #lathe #latheupgrades 
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Clamping a steel bar under the head stock would have me worried about introducing a twist in the bed. Great job on the work. I’m certain rigidity is much improved.
Its a pretty right fir so it shouldn't induce any twist
EDIT: I looked back at the footage I had, and yes it was a little low, but I did shim it tight.
The draft angles in sand castings are actually to release the _pattern_ from the mold. The mold is destroyed after each casting.
Yeah I was thinking of the wrong molding process, cheers
I like what you have done to this little machine thus far turning it from a very basic not so pleasurable to use machine into something very usable and capable beyond anything I expected. Well done, great Chanel.
Good job! Would it be worthwhile doing a test bar between centres to check that you haven't pulled a twist into the bed with tension on one corner?
Agreed, that bar looked a little too loose for my liking.
Not sure why it looked that way on camera, there was a small low spot, but its a pretty tight fit
@@artisanmakes it looks at least 5 hundreds, that is huge
@@TheMorpheus017 I think I had to add 2 bits of shim and that tightened it all up.
Also the ridges left after milling on the mating surfaces will affect positioning ever so slightly, it will want to find a high and low on a position, if the exact position corresponds to 2 high spots /ridges you won't have a total contact area
That was pretty handy having that drill bit sitting around. that's amazing how much of a difference that made. it just goes to show how much that cast iron can flex.
Brilliant! This is awesome. It's one of those things that seems obvious now, but I never would've thought of it. Super clever, and a simple, elegant solution. Very, very well done!
I was already looking to upgrade my lathe motor... Looks like I've got even more reason to do so, now. Thanks for the inspiration!
That little machine is making some amazing cuts. Great work
Absolutely genius idea im gonna be doing this mod soon thanks for sharing
Nicely done!
Most excellent. This is a really cool idea.
Good Stuff! And a great result. For those of us needing the motor in its stock location, it would not hurt to add the fourth bed-to-headstock bolt (left rear location). I did that as I also noticed that area to be quite a flimsy looking location.
That wood surface is probably resonating nicely at the frequencies you're using (that's why wood works for instruments). Buy a piece of scrap marble/granite/stone countertop and bolt the lathe to it. Then put some 4mm or thicker pieces of rubber between the marble and the wood surface. The mass of the marble will reduce the resonance, and the rubber will decouple the lathe from the workbench.
Though wood is actually really good at absorbing. But it's no way as stuff/strong as a steel bench top
It's not likely for that small vibration to transfer to the workpiece though when the whole machine is moving as one
@@cda32 i know but every little bit cound on those small machines
good fix!
Glad you were able to do this! :)
You better check your lathe for twist. Clamping such a loose fitting block under the head stock like you did would surely twist the bed.
Its a pretty tight fit so there isn't any room for movement, it lokis a little loose on camera, but its final mounting location way a pretty tight fit
EDIT: I looked back at the footage I had, and yes it was a little low, but I did shim it tight.
Thank You for the insight. Well done!
Nice work as usual mate.
Keep the content up mate, great channel 👌👍🇦🇺
Did this yesterday! Hans for the part numbers on the bearings. Seen a lot of people concerned with the thickness difference but a rat tailed file made quick work of the interference on the large black bushing.
Any time I feel un motivated to do things during the week, I watch artisan makes work his ass off with a hacksaw for a motivation boost 😂
Brilliant mate!👏
10:15 I loved the woodworking content in this video! (in all seriousness, great job! Your videos are quite entertaining)
your hacksawing inspires me!
i feel like this just goes to show how much better mini lathes could be if they were just engineered more carefully. this is such a simple fix for a problem that really shouldn't exist imho.
Neat, i have a WM 250 V Lathe, i put Lead in the Headstock, it helped a lot, gave it some mass.
This is probably a good mod. However a good other rigidity improvement is to bolt the lathe on a block of concrete (or iron, or stone...).
It's definitely something to do
I've watched a number of mini lathe videos recently as I was considering one for my vacation residence. Thanks for talking me out of that- practically every part on these things needs replacement or modification. Waste of money especially at full retail...
No worries, glad these videos helped
A handheld band saw would save your shoulders and arms from work induced long term damage. I get that your're strong and capable with your hack saw, but for your own sake, please consider this as your next upgrade :)
Brave! And Bravo!
Nice vid, good easy solution to the problem. Another cheap way to add rigidity could’ve been to add two or three threaded rods along where you added the bar and then tip it on its side and filled the void with cement.
Great stuff. Subbed.
Been watching 20 or so of your videos now - great content! I'm almost tempted to gift you a metal bandsaw or a chop saw. It's almost wearing to watch you sawing thru all this stock.
Nice video !
Ficou ótimo parabéns
Thanks for sharing …. Great job i will be doing something similar soon …
Interesting modification.
Interestingly my mini-lathe has 4 bolts securing the head stock to the bed, 3 seems a bit lacking there.
I found squaring up the head stock to the bed helped improve rigidity too, as the unflat base of the head stock was adding some twist to the bed.
Great improvement your tutorials are so much help.
Can you please send us of your biceps with all that hacksawing you must be pretty fit.
Another way (that I did) is to buy a 20-30mm thick steel plate and place between the table and the lathe. (Mine was a left over so I did not have to pay that much.) The plate is as long and wide as the "oil plate" under the bed.
I first drilled holes for the ordinary two bolts. Then I added four new holes so I could tighten the bed even harder onto the plate. I placed a few shims between the bed and the plate, at some places, before thightening in order to keep everything straight and nice.
This has really improved the rigidity on my Bernardo Profi 400.
Another improvement you could do is a 4th headstock mounting bolt. There are two manufacturers of these lathes. One makes them like yours. The other makes them better in several ways. Firstly is four bolts mounting the headstock instead of three. Second is the saddle is a rectangle instead of the lighter "H" shape. Third is the apron is thicker and has two ball bearings on the carriage crank shaft. Fourth is a locking adjustable nut on the leadscrew to the right of the right end support block. Put a brass washer on either side of the block and the nut can be adjusted to eliminate all sideways shifting in the leadscrew.
Just noticed that the motor cut-out in the bed underneath the headstock is potentially a massive design flaw - isn't this where you need the utmost rigidity in the entire lathe? Decades ago I could have knocked up a computer finite element structural analysis model to show you how such a cut-out structure would deflect under cutting loads... kudos to you for making it more rigid. But if all of these generic 7x14 lathes are designed like this then I'm staying well clear of them
thanks for sharing!
Good work you have done there. I have subbed to your channel.
Regards. Steve.
I really like this mod!
I've heavily modded my mini lathe, but haven't seen this one before. There's an idler pulley, connecting to a larger motor, where the old motor used to be on my machine. However I might rethink all that to implement this mod at home.
Well done!
I'd love to see more testing, maybe with some data.. same cuts before the mod, the amount of deflection then vs after...
Also curious if putting that block in there twisted your bed at all (either from the compression of the bolts or jamming the block in there if it was a really tight fit)...
On that note, it may be time to check your bed for twist and align the your head and tail stocks.
Best from California.
Loving the vids but time to upgrade to a bigger lathe. You have earned it.
Maybe bolt the lathe to a piece of 1/2" steel plate on before the splash pan before bolting to the wood bench will help for those of us who still have the motor in the well.
I fabricated a heavy weldment that fits underneath the bench top. The bench top is 3/4” plywood reinforced with 2x6’s spaced 12” assembled with screws. The bolts that fasten the lathe bed to the bench top pass through the weldment creating a sandwich.
Is there really only 3 bolts from the bed to the headstock?
Can you add a 4th?
The vertical element you justadded will twist everything as it wasnt a zero clearance fit... ie too short.
Its a pretty tight fit actually, not sure if it looked that way on camera. There was a small low spot but its not mounted there
EDIT: I looked back at the footage I had, and yes it was a little low, but I did shim it tight.
Ade's workshop is fixing up the same mini lathe and added a fourth bolt for the headstock, and sat the whole thing on a steel box section pipe to be filled with concrete to stiffen things up a bit.
I would've put there a 20x200 or so steel bar along the whole back of the bed
Nice work, lots of extra meat added won't hurt the lathe operation one bit, cheers!
Lucky you with your soft Chinese cast iron. My Indian lathe from the 70's is made from the hardest iron known to man and is a right prick to modify. On the bright side it doesn't seem to wear out.
Great job! Hope you will be able to take even more afrer epoxy fill
A forth bolt in the head stock may help, ades workshop is doing a lathe like yours, check him out, great video, keep'um coming..
Im looking forward to a video where you recast a custom lathe bed.
Can I (thoroughly) recommend a Makia 18v bandsaw. You will wonder why you never did this a long time ago!!
I'm curious if you've come across or considered engine block filler for filling voids and adding mass? Seems to be a viable budget friendly alternative to epoxy granite
These mini lathes really are full of flex and wobble and play. I hate mine! 🤣
Great modification. I'd have thought a plate of 3/8" steel under the whole machine would help damp too?
My mini lathe has this same flex problem. I'll see it on backing out and that small skim cut I'll get. I'm using the factory motor so it's currently in the way for your mod. I might have to see what I can do to mine. I'm not sure you addressed the entire flexing problem. Mine happens down the entire bed. Clearly my bed is flexing anywhere along its length. It is bolted down to a 3" thick bench top. I'm sure this mod helped, but I'm wondering about a thick hunk of steel for my entire 20 inches of bed.
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I already had a conical bearing at the chuck from the factory, but added one to the rear of the spindle. That was a noticeable improvement. I recommend this to anyone with a mini lathe.
i might give using toe clamps for my vice. The flanges are just weirdly spaced on my vice - I have to use the inner T slot with the location of the flange mounts to be able to have enough travel, which is a pain!
i would check to not bend the surface while snugging down the bolts on that brace
Thats really good! I saw this from an other youtuber lately and thought to do this to my lathe too. Seems really necessary to eliminate this source of weakness. Unfortunately in my case the motor sits in this little cavity, have to to modify that.
I'm not sure, if you introduced a twist to the bed. The steel block seemed to sit a bit loose and by tightening the bolts it might have deflected the bed.
And by the way, how do you manage to produce that much videos o: :D respect!
I did have to shim it a bit since I made the block a little under size to avoid it twisting the lathe.
The video schedule is a bit difficult but a lot of this is old footage from the beginning of the year/end of last year that I'm slowly getting through editing. It's bit easy but I enjoy it.
@@artisanmakes great:)!
Now you just need to bolt it to steel plate workbencg and fill the headstock with epoxy granite to kill some of the vibrations that comes from there ( it's basically a hollow metal box that also vibrates) ( with a pipe around the axle so that doesn't get stuck) and you done almost every thing I would had done with a mini lathe ( at least for now
a metal plate under the countertop would be good also you could have the bolts and washers hold it up to the underside to give more weight and rigidity to the wooden counter
Looking forward to filling the bed cavities should make a difference
Great work ! What do you think about brazing cast iron reinforcements instead of bolt a steel bar ?
Danger of distortion using heat
You mentioned that your vice was moving as you tightened up the bolts, I have had problems when washers have taken a “set” and kept shifting as the bolts were tightened, possibly new or thicker ones may help
Also tightening bolts a little at a time and sequentially
3:50 limited with vertical travel on your mill. I've always wondered why the bed couldn't have a Hardie hole like on an anvil. Maybe you could be the first...
Very nice channel! Did you consider shimming the block at top or bottom? Just thinking there may be some deflection in the ways now.
yes I did, I had to shim the bottom to get it to fit tightly
I wonder why didn´t you add a fourth tread hole to assemble the head stock. From my point of view this would make the construction much more rigid too. I think there are only three bolts for the headstock due too less space above the original motor.
Hi, excellent videos and narration, have you thought of drilling into the headstock and putting grease nipples in between each bearing so they could be given a shot of fresh grease every so often, I have a Hobbymat lathe and is a very similar setup so will be doing this to it, regards Doc Cox.
I tore the lathe apart to redo the grease after 6 months and it still seemed to be well lubricated, so I dont think regularly replenishing the grease is too necessary
Maybe you should think about setting the entire base (length and breadth wise) in concrete in such a way that it can be bolted directly to the floor. Not sure if such an initiative would be worth for this machine. I also suspect that the loss in rigidity can also be attributed to an extent to the fact that it’s bolted to a wooden table.
At that point he may as well just get a block of granite and some linear rails, throw the rest away, and just use the lathe spindle.
If you search Epoxy Granite there is a good video of diy product with mixture comparisons. Very interesting and certainly doable.
What gears are you using to get a fine finish please mine seems to go too fast and leave lines
Is that just water as coolant at 3:40? Another question, seeing that you use a vacuum to suck the shavings from the machine. How do you dispose of the shavings? Where do you dump them? It'd be nice to know.
The coolant I use is a 10% mix of semi synthetic coolant with water. For chips, I use a bagged shop vac and I just throw out the chips in the rubbish. I don't produce enough chips to warrant recycling.
Hi, can you tell me what kind of end mill is being used @3:22 ?
Take a look at Ades Workshop as he's upgrading the same machine.
I wonder if steel railroad track can be machined and used as a lathe bed.
I wonder if spot welding the block in place might actually be better? That way there is no issue with perfect fit. One should take it carefully though, not to dissipate to much heat into the lathe bed, and warping it that way instead.
It's a bit sad, but I suspect both shipping weight and general customer preferences work against making the lathe castings heavier and more rigid. In fact, even the lenght of the bed is sub optimal. Just a bit longer - classic proportions - than the "stubby style" that the Mini Lathe has, makes working more practical in my experience. But I suspect also here, market demand is for a shorter bed.
I dont think you can spot weld cast iron
@@artisanmakes Embarrasing - I don't do any welding myself! So I really shouldn't speak much about it.😁😅I have done a reasonable amount of turning, milling, casting, soldering/brazing etc in my life, and I do have my own lathe (second one I own) and mini mill, so I'm not generally speaking of things I don't know.
About size and weight, somewhat incredibly I was even given a "small" manual industrial lathe for free the other year, but in the end I very sadly had to turn the offer down, due to freight/moving considerations, and floor weight requirements of that machine. It really agonizes me, and may well to some extent haunt me for the rest of my life. When I was a teenager, I would have killed to get such a lathe! And then 45 years later, I turn such a free gift down.
Thank's for a nice channel! I'm kind of maybee possibly nearing retirement, so maybee I'll get serious (again) about shop work in coming years, like I was in my youth? During my work life, I've hired other people to fabricate things for me.
And in the end I never did scratch build a live steam locomotive, but instead bought an Aster kit and also other already built up locomotives, that I just used my lathe to modify parts for.
But I have been hand's on involved in shop work on prototypes - just because I actually love machining etc. I don't even do my drawings on computer. Computer drawing didn't exist when I went to school and university. Instead so far, I've hired people to "transfer" my paper drawings into CAD/CAM stuff. Frustrating and sad really.
one small problem i see , if the piece you put in is slightly small (as you have to fit it in between two sides ) and bolt it up from those two sides you pulling them together , so you can end up with a slightly twisted bed , you probably can shim that out by raising the foot where the motor used to be though but it will cause the whole bed to be under tension
yeah for sure, I had to use a few shims to get it perfect
Could I ask why you don't use a metal cutting bandsaw? Is it because of the cost, available space or don't like.. just curious.
Mostly due to the space I have to work with. There aren't many hand held ones sold in my part of the world and the one I have used I wasn't too impressed with
my mini lathe is in shambles due to the bed of the lathe not being flat and causing binding issues and cross slide rigidity issues.
The tailstock doesn't align with the headstock properly causing drills to bend as they burrow into the part and widen the hole at the entry.
the bed doesn't fit my surface grinder table so i cant flatten the surface. and its sat in pieces on a table since fall 2021.
im tempted to just finance a tormach 8L lathe. i wouldn't have to deal with literally everything being a rigidity issue.
As i motor do you think a beffy servo would also work? I’d prefer to not have to find a nice VFD+Motor that can reach these RPM’s.
it should work
I dont see why not
All it takes is to use an indicator to see if you are pulling the bed down while tightening, you do have an indicator and mag base?
That is a great idea, I'll have to do that when I next have the lathe apart
ar you using plain water as cooling in the mill? i have never seen a coolingliquid as clear as that
Its a semi synthetic, low concentration, but im looking to replace it
i've been looking at this lathe, i need something to turn plastics and sometimes wood. i'm wondering how well it works for that without all of the mods, i both lack the skill to do this metal work and lack space where metal working would be ok. my workshop has a carpeted floor and i do not want to be picking sharp metal shavings out of the carpet for the next decade, hah.
maybe with just the mods i can buy it'd be ok, maybe there's an awesome shop vac mod that'd prevent shavings from getting everywhere?
You should be fine to do plastic and wood with this type of lathe in its stock form. Just properly tighten the gib strips and carriage retainer strips before you use it
Imagine if you fill everything with a mix of metal chips and epoxy
Why did you use roughing end mills? For better fit, I would have used finishing end mill. Cast iron is machined with low rpm.
It deals with the DOC butter with a rougher. And anything other than high-ish rpm didnt do any good with that much stick out
Increasing headstock rigidity, at all, and your solution, in particular - there are well and right. But I guess you were needed to cut bottom seating place the same as a top, way out, but not as a close area.
If both, top and bottom, seating places were open one end, you would be able just slide the strut in. In this case you would be able to use a maximum possible height strut and would be, almost, spared the opportunity to bend the bed.
The way you did it - am afraid you were bended the bed. A bit, but... The verification ruler or dial indicator may shows you what am talkin' about...
Doesn't seem to be any twisting. It was all shinmed tight to avoid this and the lathe doesn't seem to be turning a taper. Happy days :)
@@artisanmakes So you're in luck...
Question, what happened to the high/low selector?
I think his lathe is single speed.
A good idea, but surely having torqued down those bolts, unless the length of that bar is exactly right, including any compression and surface distortion/inaccuracy, you will have twisted the bed to conform to the bar, which will translate as error in the bed. Should have just filled it with epoxy.
Had to shim it to size. It proves to be much cheaper than epoxy
at least you can say your lathes "got balls"
what type of steel bar you use?
hot rolled mild steel
Epoxy granite would be perfect for this
u have huge mill, mine must be smallest red hf mini
what rpm was the 1 mm cut?
Somewhere around 700 rpm from memory
Why you don"t use epoxy granite?
Well the steel post in the headstock worked so I saw no need to use it, plus epoxy granite it quite expensive in my part of the world. As for doing the bed, there isnt much flex it it, there are other areas that are more important than that that would see noticeable improvements.
A finished photo would be appreciated.
The whole video is a finished photo
The best thing you can do for rigidity is having the tool cutting edge as far back (to the right) as possible in the cross-slide: If you look from above the cutting edge should ALWAYS be on top of the cross-slide bed.
By far the major rigidity problem is how narrow and light the cross-slide is. Having the tool stick out on the left of the crosslide even a few milimiters is enough to make a lever between the tip of the tool, supported on the left cross-slide way and pulling the right gibbed way up, this is the shatter you see, boring bars are a specially problematic. I would recommend moving the toolpost hole on your solid toolpost stand as far right on the cross-slide as possible and preferably have the cutting edge of the tool on the center of the crosslide, this way the forces to be applied straight down on the cross-slide with no rotation forces and without pulling the right side with the gib up, it will also improve the use of boring bars but for those I recommend a gib locking screw.
For small machines a good well supported toolpost is also important, I understand people like dovetail style toolposts because it's easy to make new toolholders but those indexed euro style multifix are easy to attach (round and relatively small mating surface) and the spring + multi teeth system makes the tool holders much more rigid compared to our cheap/homemade dovetail toolposts.
I just filled this area, the whole bed and the head stock with epoxy granite. It's curing in the shop right now but I have high hopes!
How is your lathe performing now..
Please share your views
@@RoyMeraki Haven't been able to test it as well as I want as I'm not done with my solid tool post to replace the compound slide yet.. That being said, it seems to have been a massive improvement. Getting the whole machine to vibrate like it sometimes did before is virtually impossible now.
It's about 10kg of epoxy granite in total, filling the whole bed casting, the area where the stock motor sits and I also filled the headstock up just below the spindle bearings!
The disadvantage is I have to pray to god the headstock stays aligned as there's no adjusting that ever again now...
I'll try to remember to share results once it's done!
@@josefstalin4532 thank you for thoughts.
Would definately wait for your review post your solid tool post mod. I have lathe 14X40" and is resonably stout weighing in at 850 kg. The grief I face is only with parting.
I heard that epoxy granite stays resonably accurate after curing and is not prone to deform, do you really think that epoxy fill could warp machine castings ?
@@RoyMeraki I'd say it's very unlikely, at least to a measurable degree. Just make sure to get a really slow curing epoxy so it doesn't heat up too much.
@@josefstalin4532 in india slow curing epoxy is not available pot life is approx 2 hours and full cure to 24 hours. if it generates heat I will apply probably in layers.
That bottom bolt is loose. You didn't tap it deep enough, it bottomed out! The washers are still floating, the head is like 1mm away from the washers
It just needed an extra half turn with the socket set. I just didnt film it
Need more feedrate on your cuts.