# lathes, bits, ruined comms



## Scoob (Dec 8, 2005)

*lathes, bits, and ruined comms*

I recently baught an integy auto super lathe with carbide bit. I have had trouble. I used the method in the video from the motor articles in this forum because the lathe didn't have any method included in the directions. I guess they assume you know how to do it. I used old arms that I didn't care about to practice. The feed on this lathe seems to be alot faster than the one in the video. I could never get the comm to look true. For one thing the arm always jumped a little when I tried to make a pass. I'd touch the bit to the comm, take it off the end and when I try to pass back across the comm the arm would shift a little when it touched the edge. I tried to lock it down tighter in the v-block but it would bind and jump out. I ruined my bit too, it has a flat spot on the bottom of the cutting edge now. I think it's the cutting edge, the directions didn't tell me which side of the bit is the cutting edge  . I'm so frustrated. Is the flat side of the bit the cutting edge?

The comms looked terrible. I used oil on the comm after the first pass. When I bring the bit back across the comm it would be barely touching at all even though I moved it in to where it touched, took it off the end and brought it back across. Basicly nothing went right. This is way too difficult for me!

The lathe uses little metal shims to set bit hieght an I set it up with two on bottom and one on top which was a recommended starting point.

What should I do? I'm afraid to buy another bit cause I'll just ruin it too. Is there a website like: cutting comms for complete idiots?


----------



## Scoob (Dec 8, 2005)

Well I just figured out what I was doing wrong. I was using the wrong part of the bit  

The part I flattend isn't even part of the carbide. I just cut one (that sounds funny  ) and it looks great. It acually worked like the video this time. I feel like an idiot. It's just hard to figure out on your on, the instructions were very confusing and lacked detail.


----------



## baih (Sep 26, 2001)

on your final cut, coat the comm with a black sharpie marker. magic marker doesn't work as good. or coat the comm with wd40 for the final cut.

i like using wd40


----------



## SuperXRAY (Jul 10, 2002)

Well, WD40 is pretty harsh to use on copper, but ok. WD40 is good, basically, for nothing.  Lots of people use it though.


----------



## burbs (Apr 21, 2002)

you best bet it to contact someone locally who can set up your lathe and show you how to do it... until you see how it is done from someone who knows, it will be tuff to get it right.. I had to have someone show me many years ago.. once you see it tho your good..

with a carbide bit i recomend using a light oil.. not wd 40 tho.. I use bushing lube.. Its a bit thicker and helps the comm look better.. A carbide bit wont have a very shiny finish either like a diamond bit.. I also dont recomend getting a diamond bit until you get real good at cutting.

if your arm is shifting you dont have it shimmed properly.. You have to shim the arm so it doesnt move side to side.. I always use a super small pinion.. i put it on the shaft on the side it sticks out.. this will keep it locked in and you wont need all the little shims...


----------



## Scoob (Dec 8, 2005)

Thanks for the advice guys. I cut two good arms last night and both turned out pretty well. 99% of my problems came from the fact I was using the bit backwards   . The arm shifting went away after I turned the bit around.

I've been using Trinity royal oil bearing lube. It seems to work fine.


----------



## scootr117 (Dec 7, 2005)

I've got a question on lathes..I bought a used MOD fashion lathe. Nice little unit since I put a new bit in it. The thing I need to find out is what guys are using for drive ring/belts...the original is looking a tad shabby and the auto store O-ring I bought to subsitute broke. Also today I used two drive rings to stabilize worked really good


----------



## ta_man (Apr 10, 2005)

I use hardware store o-rings. Probably the same thing. I think it is important to get the right size. I got an Integy X-Mod lathe about 2 years ago and I have used the same armature drive O-ring I got from one of those yellow boxes at my local hardware store enough to wear out quite a number of carbide lathe bits. The O-Ring still shows no observable damage.


----------



## scootr117 (Dec 7, 2005)

Thanks.....I must have gotten a smaller size...I assumed the original had stretched and bought one that looked simular..Rookie mistake.


----------

