Using your CNC Mill as a CNC Lathe

[lstool]

Yup,
I was answering a post about those 3 in 1 combo machines and stated that I woulden't touch those combo machines with a 10 foot pole.
Than got carried away as usual and wrote the following and decided it might be worth while putting here.......

Nuthin like a nice Bridgeport. I don't know if any one here has done this before but before I got my CNC lathe I have used my CNC Bridgeport as a CNC lathe many times.

1) Once you can chuck your work in your spindle (via. fixture or custom made chuck for your spindle, R8 in my case) your on your way.

2) You can make a nice fixture to hold gang tools 4 or 5 tools or more if necessary even drilling & boring

3) Now it gets a little tricky (you are programing radious not diameter) you have to fool the machine in the way you program to turn your parts.

4) (remember you cannot do this if you cannot programe your spindle) now to keep the machine from going home for a tool change (and we are not changing tools we are moving over to a new tool, also we cant forget about those dreaded tool offsets when you are using a few tools) you wright down the offsets and position to that offset for that tool in absolute (add .100 for clearance) and programe in incramental. or to advoid all that if you have the luxury to do so depending on the job set all tools at the same .000 level using your spindles readout to accomplish this.

There you have it, turned your CNC mill to a CNC lathe this is only worth while if you are making alot of parts and you dont have a CNC lathe on hand, Or as in my situation at the time Your CNC lathe had not yet arrived and you had to get the job done one way or another (but definately not manualy). or perfect for contouring. so for all you guys building a home CNC mill concider keeping that spindle as hefty as possible you may want to turn some nice parts. You can never have too much spindle anyway.
Happy Machining

[Rekd]

I've made a few *ahem* booboo-plugs *cough* and some simple stuff with a knee mill. Never fixtured up a job for one though. Good idea.

[lavrgs]

I would like to learn more about using a mill as a lathe. I don't have a mill yet but I have identified a Bridgeport V2XT as a good choice for parts I have plans to make. When using Mastercam what would be the basic approach and would you use a different post? I am a complete beginner with Mastercam and I can't picture how I would spin the part or create the tool paths. Any insight would be appreciated and I will go practice...
If there any sites (besides this great site) that you can recommend that would be helpful too.

[Kevin Taylor]

Look in the BTC clubhouse in the BPT forum I posted my pic's of this The program is prety much the same as a CNC lathe but you may be backward's on the X sine depending on where you put the tool I made a backplate to mount a 4" three jaw on a TG75 holder and improvised the coolent line you could G92 the X differently for each tool A collet holder would work great for small part's Good luck Kevin

[lavrgs]

Thanks for the reply Kevin but I was kinda lost in around the area where you said BPT and BTC

[Kevin Taylor]

BTC clubhouse!#*$!

Kevin

[skorboard]

Hello everyone.

I am new to the site but love all of the helpful information that is here. I noticed the comment about using a mill as a lathe. This is something the old-timers passed to me awhile back. I made some Brass bridgeport handles for a Bridgeport to test it out. I have posted a video to show what I did. So if you are interested, check it out.

Bill.

Turning on a Milling Machine Gold Bridgeport Handles one of a kind EMC

http://video.google.com/videoplay?do...4267545192193#

search key words gold bridgeport handles

[lavrgs]

For some reason the video didn't work for me. I was able to see other google vids but this one looked like it loaded and they wasn't any action...

[skorboard]

Hmmm, I can't seem to see why the link wouldn't work. It works for us. Anyway you can always search using the keywords gold bridgeport handles and it should come up... it is the video of the giant Green gantry mill.

Good luck.

Bill.

[lavrgs]

I tried again and it worked. Any tips or programming? I wouldn't know where to start. Would you use lathe functions or mill functions?

[skorboard]

I used the MasterCam lathe programming and it seemed to work well. I have not tried anything else but I bet someone here has.

Bill