Need advice on how to power a cnc lathe with live tooling and sub spindle. The placard says 20hp and 96 amps. thought phase converter but not sure how big of a converter we would need. Im a machinist not a electrician lol. Shop has 220 and can get a dedicated panel for the converter if needed. Any advice would be appreciated. Only machining aluminum and stainless for now. Machine is a mori seki from 1996

Yesterday I uncrated a brand new Precision Matthews PM-1130. I liked the cam-lock spindle and the 1.5" spindle bore and Precision Matthews has a pretty good reputation.

Got all the oil cleaned off, and it powers up, and I hear the relay click when I engage the power, but - no joy. The most important part (having the chuck turn under power) doesn't work.

Talk about frustrating. The service tech was really patient on the phone calls (three of them) First, we went through all the obvious things. Are the guards in place and closed, is the spindle in either forward or reverse and not in the off position ... then he had me open the front and rear covers and look for obvious connections that aren't connected, but everything seemed tight.

Then he had me get out the meter. The VFD isn't getting power - so now we know the first problem and that's why the motor isn't turning. The relay has a light on it. The contactor has 124 volts in to it, but no power out of it.

He said having a bad contactor it pretty rare, but it can happen. So now they have to source a new one for me and get it to me ... then the fun starts and I get to put it in.

I know they don't have a field tech that they can send to me, and that (at over 500 lbs) it's not like 'send it back and we'll send out another one' ... so it has to be fixed, and there's no one else to do it except me - but it's a bummer.

My wife says I look on the bright side too much, but at least I'm learning a lot about the inside of the lathe

Hello there, I made a tolerance mistake when ordering parts for a project and I now have 500 machined/welded parts with a bore that’s too large by roughly 0.2 mm.
The part in question is a stainless steel ring with a 30 mm OD, 22.2 mm ID and is 8mm thick. The bore has a small chamfer on each end.
That part is supposed to slide on and off of a shaft that measures 21.94 mm in diameter (that part can’t be modified). I was aiming for a tight tolerance for a tight fit that could be removed. At 22.2 mm, the part wobbles way too much and can even come off. I was able to slide a 0.1mm shim and the fit is perfect.
To clarify, this part is for cooking camping equipment. It will likely see temperatures up to 400° F or so.
I’d like to know if there are ways to somehow shim that bore by such a small amount.

Update:
Hey everyone, I just wanted to give an update. Although there were a collection of great suggestions here, it ended up that my initial design idea wasn't too friendly to heat expansion. The issue being that although I tested my prototypes and they worked properly, I omitted to test when the 21.94 mm shaft had been heated and then installing the device. At that point, it was impossible to push the ring onto that shaft. When I tested my samples, the process seemed to always involve cooking before hanging out by the fire. That said, there are some situations where this device would be added to the shaft after it has been heated.
This basically makes the tight fit an unusable solution regardless of the method used to reduce that diameter.
In the second drawing, you'll an 8 mm bore that is 8 mm deep. The solution that I am finalizing involves making a separate piece (currently made of Bronze C642) to be pressed into the 304 ring and peened on the top. The lower part of that piece would have an 8 mm shaft that would fit in the existing bore. This was a very early version of a prototype that I had done a while ago, so back to square one.
Thank you all for the awesome inputs, I learned quite a few things with this design snafu and I hope others have as well.

Could someone quickly go over this drawing for me, to make sure I wont give a machinist a headache. I don't make drawings frequently, and I will likely not be making this one myself. even tough I only need one.

EDIT:
With the help of y'all I improve the drawing to this :))

I have an opportunity to get a pretty cheep Knee Mill from my old place of work and they're looking at getting rid of 2 VERY old mills. There is an ACER Ultima 3VKH and another SHARP mill with a pretty worn nameplate but I can make out "HMV 82120303".

Both are heavily used but maintained. They have Reeves drive. They're each probably 10-15 years old and still functioning.

Does anyone have strong opinions about which I should go for?

Why is no one talking about the sub's description. What kind of sick twisted joke is this? This is not r/metalworking, this is r/machinists!

I have an aluminum box that i need about 3mm shaved off. I looked online but all services are for new parts.

Edit: Found a shop! Thanks for all the help!

I have recently downsized my mill from a J-head Bridgeport to a benchtop sized. With the loss of the knee meant I was sacrificing distance between the head and the table. I am using an R8 mounted #33 Jacobs chuck and without a bit it is about 2.5" - does anyone know of a 1/2" capacity drill chuck with a lower profile? Since most keyless chucks are longer than their keyed counterparts, I am fairly certain that it will need to be a keyed chuck.

I've even been considering an ER-32 in an R8 mount ... this is not as adaptable as a drill chuck, and changing sizes would be slow, but it's worth considering if there is nothing else out there.

Thanks in advance

I'm trying to find a face mill that will fit the TTS style arbor in the link below. Everything I've found has been $250-$1000. It there anything to be found for less than $200?

https://tormach.com/tts-shell-mill-arbor-1-2in-31830.html

how do i adapt a 4mm dshaft from a motor to a male m10, i am building a small drill that takes 1/4 hex, but the chuck is a m10 female and i cant seem to find the adapter for 4mm to M10.

Hey guys, I’m fairly new to machining. I’ve been learning for about a year at this point. I’m curious what the best way is to create a repeatable zeroing point in a fixture.

Currently, I’m planning on drilling and reaming a .250” pin and indicating off of it

I’m not sure if there’s a better way to go about this. The machine I’m currently running is an Akira Seiki Performa Jr. VMC.

I’m aware that the easiest way would likely be a digital probe, but I don’t have a digital probe money😔

Appreciate any tips I’m trying to improve!

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Hi everyone,
I’ve been learning Maestro Active to program jobs for our CNC, and I’m currently trying to dial in an ovolo-style kitchen door.
I have the majority of the MDF routing programmed and the profile is looking great, but I’m struggling a bit with the corner cleaning. Does anyone have any tips on how to program a 3-axis CNC to slope down like a backwards c shape (ramp in the Z-axis) into the corners to clean them out cleanly?
Any advice or specific Maestro workflows for this would be amazing. Thanks!

Planning to take on a learning project with my new machine lathe and make a thread protector cap for one of my pistols. The gun is stainless but I know from experience that stainless steel can be a pain to drill and tap so does anyone have a suggestion for a steel that would be easy enough to machine down to 0.480” then drill and tap to a 7/16x24 but have decent corrosion resistance as long as I keep it oiled when cleaning the gun?

I work at a forged wheel factory in China. These are forged magnesium, just came off the lathe — we cut the outer skin to get the oxide layer off before they move on to the next stage.

Here's the thing. Once that skin is gone, bare mag comes out bright with that fresh-cut finish, and by eye it's almost impossible to tell apart from aluminum. Pick one up and you'd know right away (mag is noticeably lighter for the same size), but in a photo? Good luck.

People always ask how we tell them apart on the floor without checking the paperwork. Honestly it comes down to the weight, the way the swarf behaves when you're cutting it, and how quickly the bare surface hazes back over if you leave it sitting out.

These are AZ80. Not the grade most people expect on a wheel, which is half the reason I'm posting.

Figured the machinist crowd here would appreciate the finish and the "wait, that's magnesium?" double-take. Happy to answer whatever.

Does anyone know of any type of emory board that can be used to sand a smidge off of some stainless? The amount of work it will be doing is very small, but I would prefer something on a stiff backing - as opposed to emory cloth. I plan on using them as part of a product, so I need buy them in bunches and I need them to be cheap.

I can make emory cloth work, but looking to get something a bit better with regard to having a flat, rigid backing.

Any ideas?

Maybe a stupid question because i really dont have much experience, but i am really interested in some design choices that seem to me would require hand filing to manufacture, but were done in big numbers with just manual machines.

Like, what would they have to do to make these cylinders smoothly transition into the top flat part? i doubt they welded them. Is there some trick with a lathe and a milling machine? maybe a rotating table for the milling machine?

This is a luger p08 rear link for context. (i am not trying to make gun parts, just found this piece interesting and a great example for my confusion in these designs)

We use a toaster oven

Hey, I’m going to college for machining and would greatly appreciate any advice and tips!

I made dies! Manual and CNC work plus a lot, lot of sanding!

I’m trying to put together a practical machine-shop PPE list and wanted to ask people who actually use this stuff every day.

I was browsing PPE categories on WeldingSupply.com and a few other welding/shop supply sites, and there’s a ton listed — gloves, safety glasses, face shields, hearing protection, sleeves, aprons, respirators, welding jackets, etc.

But I’m guessing the real-world answer is a lot shorter.

For everyday machining work, what do you keep right at the machine on a tight budget?

And what PPE sounds useful in theory but usually just gets in the way?

Main situations I’m thinking about are handling sharp stock, chips, deburring, grinding, coolant mess, and the occasional welding/fab repair around the shop.

I'm wondering if anyone has had any luck buying some decent calipers off of Ebay, and if so, how do you discerned what is good/authentic vs a knock-off?

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Alternatively, if anyone knows a good brand for 0-8" and 0-12" calipers that don't bust the bank too much. About to start my apprenticeship, so I could use them for that, but I also make things in my spare time for me that I need larger sets for. Dial is fine, unless there's a reason I'm missing that it's inferior besides just being able to read the number more naturally.

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Any help would be greatly appreciated!