Thread: Rotary Table questons

lol Yet another moment. The drawing was wrong when I thought mine was 24 degrees. Now I've done the math's right the drawing looks better.
I should have eye balled it with a protractor.

Stuart

Hi Ray,
I've been trying to work out how the holes for the camlocs pins and the holes for the pins on the back of the chuck intersect.

Going to run the maths backwards with 14degs and see who I agree with, me or the drawing lol

Stuart

To use a degree wheel, you would mark both hole centres beside the holes. Then set a tool blank up on centre in the tool post and align it with one of the centre marks and zero the degree wheel. Once you have done this turn the spindle to line up the tool on the second centre hole mark and the degrees can be read.

Dave

I'm going with 15 degrees lol.
I wish vertex had squared off the end of the base casting. I'd like to be able to clamp fences to the table and stand it up without loosing center. maybe that can be my next job.
Stuart

Well I spent my time tonight centering everything, standing the table up and checking it for center. Then realising I don't have enough clearance to get the boring head in. So lay the table back down to remove the adaptor and putting it on 1,2,3 blocks. Lucky I bought some

This started out so well last week. Still maybe someone will read this some day and not make half the misstakes I did.


Stuart

I bet it won't happen the second time around.lol

Dave

The way today went you might just loose you money lol
No tool time tomorrow

Ok next crazy idea for my second adaptor. I want to make a spindle to mount it to so I can set up and balance faceplates.
Stuart

Just wondering why you would want to balance them when most work on a face plate is odd shaped and usually out of balance. Also it's not usually spinning real fast on these jobs.
I just rough guess the weight if it's off set and bolt on an extra bolt or hold down out of the clamp kit to roughly even it up.

Dave

Hey I can turn the handle on my table pretty fast

I've seen it in a few books(although they were talking about screw on chucks) and thought it was a good idea. I did start one job on the face plate and thought the lathe was going to climb off the stand. So maybe I'm not the best guess lol.

Stuart

What ever weight is off centre needs to be compensated by the same weight opposite,eg a 5 kg job would require a 5 kg counter weight depending how far off centre it is.

My special skill seems to be finding new ways to screw up. Maybe a VSD would help as you can bring the speed up slowly, or does the out of balance have harmonics?

Stuart

Depending on how out of balance the job is,it will be noticeable and over ride the gearing of the lathe,meaning it will speed up on the downward stroke and return to normal or possably slow down on the upward stroke.

Originally Posted by pipeclay

Depending on how out of balance the job is,it will be noticeable and over ride the gearing of the lathe,meaning it will speed up on the downward stroke and return to normal or possably slow down on the upward stroke.

I agree, put a weight opposite whatever you're turning (what change gears are really supplied for ) but I'm not sure about "over riding" the gear Peter, the speed fluctuations are minor, and at turning speeds won't be noticeable until the RPM is so slow the gravitational force overwhelms the centripetal force. At that stage you'd get the gears clashing in and out of mesh, very bad for them. What will otherwise happen is with work way out of balance the lathe will vibrate and shake like crazy. Not good for anything ... particularly one's sanity!

Pete

Today as I had cleaned the lathe I made 14 Alum magnet holders for holding the alum foil down when I am machining cast iron. Please excuse the ugly backs, the three jaw is still full of cast so they were made in a 4 jaw. I'll fix them up when the 3 jaw is clean again.

I'm now boring the holes for the camloc pins. I'm currently using 240rpm, 0.15mm feed. Should I drop the feed to 0.04mm or is that a waste of time with a carbide cutter? What's the smallest cut I'm likely to be able to get with carbide? I was planning on just cutting until it was spot on 19mm and letting the pins wear it to the 19.16mm that the holes in the spindle are or should I hone it?
Stuart