I made a small 3 stage cylinder for my power draw bar 

Dang I thought I replied to this, must have gotten eaten. Anyway, the key numbers are in the output you need to compress your belleville springs, and that's a function of the PSI you can get from your air compressor vs the diameter of piston(s) you want. Force output per cylinder is the piston area (Pi*radius^2, I just use an online calculator 😂) times operating pressure. You can then multiply this by the number of sequential pistons (3 in this case) to get your overall output force and if that's enough to compress the holding force your springs are putting on your drawbar, then bob's your uncle. With my setup my piston is outputting a shade over 2k lbs of force, enough to compress the 7/16" ID Belleville spring stack I have; it's a shade lighter than what the Tormachs use on their machines I think but I personally use light tools and haven't had a problem with tool pullout with this setup (in fact I'd only ever had a problem with tool pullout when I was manually tightening the drawbar). It's all based on different variables which is why I didn't get too deep into it in the video, hope this helps further explain some of the "Why" and "How" for you, and thanks for watching!!

@@PracticalRenaissance I'm a bit of a jerk to be honest... I run my PM-45M really hard. I also don't really have shop air since this is in the back room of my house and not in a real shop. All of the outlets are on 1 circuit. I need to see the current draw on my control box (220v) and see if I can get a small air compressor on it. Thanks for the explanation!!

Thanks Aaron! I’m very pleased with how it turned out!

Glad to hear it! Sorry it's taken so long to publish, I'm a slow editor 😂 Good luck to you if you try your own!

@@PracticalRenaissance I was going to ask what downforce you designed for but I see you answered it below. I've already started designing mine in Fusion 360. How long is the stroke?

I'm surprised you don't! 😁 Thanks Greg!

Thank you! Just remember it's one foot in front of the other, I was just a guy with a dremel and some hand files not that long ago

@@PracticalRenaissance You are doing great... Thanks

LOL its funny I probably do more random mundane tasks on the lathe than I do the mill, but of course the fancy CNC machine gets all the screen time..... 😁

😂😂 I mean, I'm just too cheap and stubborn to buy a proper one...

1000 € ??

Thanks Tom! Yeah I'm pleased so far!

Thank you for watching!

That's awesome, good luck! I don't think I'll ever attempt an ATC on this machine, there's some real smart folks out there who have made some and they're super awesome and very overwhelming for me to think about, this sytem I have right now is nice and at my level 😁

Inverting the "lathe-as-a-mill" trick, you could clamp the tool in a vise on the table and mount the work onto a toolholder on the spindle.

@@EmyrDerfel I've seen that done before, and would totally do it for small parts, but not so sure about a big cylinder. Worth a consideration though for sure

@@DarkArtGuitars other option is to finish off the cylindrical surfaces with a boring head or a flycutter with a custom insert.

Thanks! Yeah I’m always concerned with too much load on the head causing problems during rapids, although I don’t think I had any problems with the old cylinder. I used the pneumatic ratchet for a long time, it’s reliable!! I made this mostly on my old south bend 9a lathe, the grizzly mini I have disassembled for another project/idea, but it could totally have been made on that!

I just used a piece of 7/16-20 B7 grade threaded rod from McMaster. I killed hexagonal flats into the top of mine after cutting it to length, but that feature isn’t mandatory

😂😂 Guilty as charged, this was right after they nerfed rapids and I ended up paying the money right after this project lol