Today's happenings on the Tormach Lathe

So I came in to work on the lathe to figure out what it’s going to take to make drilling successful.

  • With @artg_dms help, we aligned the tool holder block to within .0001" of true and then found the magic number that will put it in the center of rotation of the headstock. Rechecked the height and found it was off a little so we adjusted that and tested it manually then measured the wall thicknesses and got it to around .001" center which is sufficient.

This is going to have to be the procedure for setting up a drill:

  • Zero the X-axis (XREF which moves it all the way to the front).
  • Set the X-axis relative number to zero in path pilot (this sets up the G54 origin register).
  • Issue the following command in the MDI screen: G0X0-8.186
  • This will move the tool to be in line with the center of rotation.
  • Set the X-axis relative number to zero in path pilot again.

Pain in the butt, right? That’s the way it has to be. I have lots of reservations people will do this correctly. I’m adding this info to my class slides but won’t be holding my breath that people will follow it.
We tested this and it works well.

  • The jacob chucks we have, have a very shallow tool depth. Bottom line - the drill bit sticks out WAY too far. The regular jobber drill bits we have flex a lot even on a slow feed and with a pre-drill using a center drill to guide it. Expect a LOT of broken drill bits. We should look into some stubby drill bits. What this implies is that if you need to do a deep drilling, it will have to be done in stages - first with a stubby them with a long drill. With the spot drilling, that is 3 stages to do a reasonable drill operation.

  • The knurling tool and wheels came in. We got it adjusted in but the default wheels are a very fine knurl. We went to change the wheels to something course only to find they are too big and wide for the tool holder. I’m afraid that’s on me. There wasn’t any size info on the tool page on amazon and I fell for the amazon “People who purchased this product also purchased…” which pointed to the set of three wheels we got. It’s not all bad news though - the wheels fit on the holders the Coulchester manual lathe.

  • We were able to produce a knurling with the tool we got but the knurl is pretty fine. It produced a lot of head (and smoke) which means the wheels are gonna clog up pretty easily.

  • Lastly, while running - the mouse, touch screen, puck, and keyboard kept cutting in and out. The path pilot kept reporting "USB unplugged. USB Plugged in. <etc, etc, etc.> What do all these things have in common? The cheap Tormach hub they provided. Plugging an accessory directly into the USB slot fixed it fine. If you wiggled the hub enough, it would find a spot that worked for a while. Looks like we should look into a more robust hub.

I expect I’ll have class slides done by next weekend and we can schedule a dry run of the class. CHEERS!

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How far are the wheels off? We can throw them on the Surface Grinder to bring them to fit.

Thank you for doing all of this!

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Sounds like an unpowered hub for the USB; not all PCs, especially low power ones, put out enough chooch to be able to handle a multi device hub well.

We should be able to use a powered hub to help with that

unfortunately - about double the width. Oh, and the diameter is larger so it isn’t a simple grind.

that was my thought as well.

No problem! Writing the class and figuring out the new machine, getting mad and cursing at it - this is my idea of fun :grinning_face_with_smiling_eyes:.

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Pict gives you some idea of the difference.

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you know - something like this might be a good alternative for some drilling;
collet chuck extension
image

It would fit in one of the boring bar tool holders and uses ER16 collets which we have. food for thought. cheers!

Nick,

Thanks for being so relentless in the pursuit of Tormach truth. You are certainly working through a lot of issues with considerable velocity.

I am glad to hear that the magic X setting for drilling was found, due to little help from Tormach at that. The Collet tool holder may be a good idea, but it will still be attached to a tool holder that is kind of light weight, to turn a phrase euphemistically. Especially the azimuth, angle, holding is going to be a recurring issue. That is not a part that will be retrofitted easily. Perhaps, drilling might have to be limited to the softer non ferrous materials.

Stubby drill bits and even end mills might be a good way to good with this machine even the short jacobs chuck setup. Makes one wonder about Tormach’s decision to include such a short chuck. Is it to conserve work Z dimension or was the weight of a longer chuck, cantilevered out further producing sag?

Thanks again,
Bob

you’re correct of course but it would have less flex since it is only 1 component in a tool holder compared to the chuck/morse setup. It would also be limited by the depth of the collet so again - stubby drills.

The horizontal and vertical angles can/will slip now and then or if the tool post isn’t seated all the way, so we’ll just have to check that now and then to make sure it’s running true. cheers!

You also might want to see if it’s USB 2 or USB 3 on the Tormach side and purchase a hub to match. It’s all supposed to be backward compatible but I’ve experienced cases where it’s best to match that up or there’s odd problems.

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The Gigabyte BRIX has both USB 2 & 3 ports. Plugging the hub into the USB 3 port might solve the problem. If not, Microcenter has a 7 port powered USB 3 hub for ~$33.

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Myself & Art toyed with that port last night. We switched it from the 2.0 to the 3.0. We did get 1 glitch with the mouse.

I feel we should go ahead & get a usb 3.0 Art suggested. Also a usb extension cable to one of those mountable flip up USB’s similar to what we used with the Metal Shops Dynatorch setup. This will allow us to mount the PC & hub neatly with still good access to the usb to plug in a thumb drive.

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Picked up a couple hubs to try, going to head to the space now from Microcenter

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Here is a short video of the threading we did.

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And it looks good.

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Oh man, sign me up. I have thread envy!

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Not only looks good but dispenses with the required relief zone past the threads one needs when using a manual lathe.

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I would be happy to record the dry run if you want…