[Steve Seebold]

I have a bunch of round work to do on my PCNC 1100 so I want to use it like a lathe, but I need to put stops in the TTS tool holders.

SO, my question is, I know the TTS holders are sort of hard, but has anyone ever tried to tap a 1/2-13 or a 1/2-20 thread in the back of them?

[SCzEngrgGroup]

If all you need is a stop, just press/Loctite in an aluminum or mild steel plug, and drill/tap the plug. The holders are hardened, and I'm sure they can be tapped, but you'd want a carbide tap to minimize risk of breaking the tap. Or, use a lathe and a good carbide threading tool.

Regards,
Ray L.

[wtopace]

I have a bunch of round work to do on my PCNC 1100 so I want to use it like a lathe, but I need to put stops in the TTS tool holders.

SO, my question is, I know the TTS holders are sort of hard, but has anyone ever tried to tap a 1/2-13 or a 1/2-20 thread in the back of them?

I like this idea for depth stops! As far as threading, I'm with Ray that I would single point the threads in a lathe with an internal threading tool rather than tapping. That way you can easily control the DOC per pass vs the tap, which would probably be too aggressive and just break if it is hardened.

Hopefully you'll post some pics once you're up and running, sounds like a great idea.

[Steve Seebold]

If all you need is a stop, just press/Loctite in an aluminum or mild steel plug, and drill/tap the plug. The holders are hardened, and I'm sure they can be tapped, but you'd want a carbide tap to minimize risk of breaking the tap. Or, use a lathe and a good carbide threading tool.

Regards,
Ray L.

Great idea. Thanks Ray. See, I knew if we hung around together long enough, you'd come up with a good idea. LOL

[Steve Seebold]

I like this idea for depth stops! As far as threading, I'm with Ray that I would single point the threads in a lathe with an internal threading tool rather than tapping. That way you can easily control the DOC per pass vs the tap, which would probably be too aggressive and just break if it is hardened.

Hopefully you'll post some pics once you're up and running, sounds like a great idea.

I'm gonna use ER32 holders and collets to do my job. I bought 2 holders, and 2 of each size collet, then I can have one in the machine running while I load a new part in the other one.

I do a lot of stuff like that. I'll make 2 fixtures usually with 2 parts each, then I have one fixture in the machine running while I reload the other.

I don't do big parts. Usually my rule is, if I can't hold 6 parts in one hand, then the parts are too big for me. Occasionally I'll put that rule aside, but not vert often.

[phoneman]

Steve
What CAM program are you using that will let you turn a part in the mill. Also how are you arranging your tooling so you can do more than one op to the part. I have some small shafts for a project that I need to turn multiple copies of.
I would be real interested in seeing how things come out for you.

Dave

[keen]

Hi - If I am tapping unknown/semi hard steel. I start with an old blunt tap, dress the bench grinder wheel, grind a few mm's off the end, carefully freehand grind the cutting chamfers, and tap away - as it is razor sharp, usually it cuts better than a new tap.

But if the steel is too hard - well the tap might chip or get too tight - but it was a worn tap.... so nothing lost. Keen

[Steve Seebold]

Steve
What CAM program are you using that will let you turn a part in the mill. Also how are you arranging your tooling so you can do more than one op to the part. I have some small shafts for a project that I need to turn multiple copies of.
I would be real interested in seeing how things come out for you.

Dave

Dave, I use GibbsCam for all my part programming. I'll program it like a lathe and use radius programming instead of diameter.

I watched a video today on making large parts on the PCNC 1100.

Eric was doing a demo on SprutCam and the number of keystrokes he had to use was terrifying. I could do that part with less than 1/3 of the keystrokes he had to use. He did however give a good demo.

[CadRhino]

Steve, I am having a hard time visualizing how you are creating/using the Ty's holder as a stop.
Please post some photos when you get it set up.

Great idea. Thanks Ray. See, I knew if we hung around together long enough, you'd come up with a good idea. LOL

[IMT]

Steve,
Can you threadmill the holder from the back side? I have successfully threadmilled hardened steel many times, around HRC 45.

phoneman,
I use SprutCAM for turning on my mill. For Machine use "Lathe with Opposite Spindle". After postprocessing I manually edit the g-code to reverse the sign on the X and I coordinates. (easy to do using find/replace in notepad). Setup is with the cutting tool on the right side of the workpiece.

[phoneman]

IMT

I have sprutCAM9 so I will have to look into that. Please clarify "reverse the sign on X and I" . Cutting tool on right side so the cutting edge will be facing away from me.

Did you build any kind of special tool holder or a quick change tool holder?

thanks for the info

Dave

[IMT]

IMT

I have sprutCAM9 so I will have to look into that. Please clarify "reverse the sign on X and I" . Cutting tool on right side so the cutting edge will be facing away from me.

Did you build any kind of special tool holder or a quick change tool holder?

thanks for the info

Dave

Change X+ to X- and i+ to i-.
Yes, cutting tool facing away, or you can face it towards you and reverse the spindle direction.

I don't use a tool holder for the workpiece. Small parts I do direct in an R8 collet. Larger aluminum parts I pre-mill a .750 diameter by .500 long boss and add a .250 wide shallow relief to mimic a TTS holder and use the .750 R8 collet.
Attachment 294056

[Steve Seebold]

IMT

I have sprutCAM9 so I will have to look into that. Please clarify "reverse the sign on X and I" . Cutting tool on right side so the cutting edge will be facing away from me.

Did you build any kind of special tool holder or a quick change tool holder?

thanks for the info

Dave

With my GibbsCam, I can program just like a lathe. The X's, Z's, I's and K's will be exactly the same as on a lathe.

But I gotta modify/lighten some pistons first.