Milling Machine Vice Angles

T

Tony Zinzola

AzB Silver Member
Silver Member
I have a Milling Machine and bought an Indexing Head from Chris Hightower. This is basically a lathe bed with an indexing headstock and a tailstock which attaches to the Milling Machine with a Swivel Vice.

It's been sitting around for about six weeks untouched because I've been so busy with work and other things. I'm finally getting ready to get this thing set up.

My question is do any of you use something like this for cutting points and if so, would you have the approximate angles needed for 4, 6 or 8 point cues?
 
Tony Zinzola said:
I have a Milling Machine and bought an Indexing Head from Chris Hightower. This is basically a lathe bed with an indexing headstock and a tailstock which attaches to the Milling Machine with a Swivel Vice.

It's been sitting around for about six weeks untouched because I've been so busy with work and other things. I'm finally getting ready to get this thing set up.

My question is do any of you use something like this for cutting points and if so, would you have the approximate angles needed for 4, 6 or 8 point cues?
Click to expand...

If it is the type that I am thinking of, it is the number of points into 360 degrees. So if you want 4 points its 90, 180, 270 and 360. 6 points would be 60, 120, 180, 240, 300 and 360. 8 would be multiples of 45.
 
Tony Zinzola said:
would you have the approximate angles needed for 4, 6 or 8 point cues?
Click to expand...
It will depend on how wide you want your points to be at the base which in turn has to be coordinated with the final size of your forearm. It's all basic geometry.
 
TellsItLikeItIs said:
It will depend on how wide you want your points to be at the base which in turn has to be coordinated with the final size of your forearm. It's all basic geometry.
Click to expand...

I have a set-up like that that I made and was very unhappy with the results. The angle the vise needs to be set at is less than 2 deg. and all the different numbers of points fall into less than a quarter of a degree. What little play there is in alignment when mounting the vice to the table and the degree wheel numbers being so small makes repeatability nearly impossible.

What I did was eliminate the vice. I then put a 2" length of aluminum bar, that was a snug fit in the mill table slots, onto the bottom of the plate of the jig. I mounted this bar with one bolt so that it could pivot. When I want to use the jig, I set it onto the table with the lug in a slot and using a 6" digital caliper, I measure from the side of the table to a mark I have on the other end of the jig so as to have it set in the exact angle that I need for a particular point length and depth that I had already tested before hand. I then clamp the jig in place an set my cutter to the correct height and away I go.

To get these angles, one day I turned a number of tapered dowels to finished prong size. I then mounted them and thru trial and error, determined what angle and how far from center to make my groove so as to make the points the width and length that I want. I then wrote down the distance from the table face to the jig and the depth from center on all the different point numbers for future use. I make my points 9" long on a finished cue and I make the depth as deep as I can so that the points are very near each other at the wrap. Repeatability is a snap doing it this way.

Dick
 
Yep, I'm not sure a vice is the best way to go myself. I used two pieces of flat stock with a "swivel" point similar to what you've done (indexer on one end tailstock on the other). Once I worked out all my different angles I drilled a 3/8" hole through the fixture with the mill and just drop a stainless pin in the hole. That allows me to put the fixture right back to exactly the same setting.

I also drilled some locater holes for the fixture to mount to (into the bed). If I need the mill for some other chore I just remove it and get on with whatever.

I also did the same as you with the tapered dowels to finish size. Sometimes ya just don't need no stinkin calculator ;) (Sorry Sheldon)
 
> Is this just a series of holes with a rod to hold the head in place,or a true indexing head with a crank? If it has the crank,you divide the number of holes (usually 40,most are made on a 40:1 gear ratio),by the number of locations you wish to mill the part. Let's say you want to cut 6 points. You divide 40 by 6,giving you a mathematical answer of 6 and 4/6. The 6 represents the number of full turns made,the 4/6 can be reduced to 2/3,using the lowest common denominator. The 2/3 can be divided into 39,the full number of holes in that circle minus the one the peg is in at the moment,giving you a solution of 26. In this case,you would turn the crank 6 full turns,then 26 holes. This calculation also works if you want to use say a 1/2 end mill in the spindle,and want to turn round stock into hex stock. Tommy D.
 
The vise is so easy to take the fixture on and off with. So if you feel the rotation is to hard to calculate. Then look at how long the vise jaws are and put two wedges for the different angles on each end of the vise jaws an opposite sides. Just experiment with it. A little math will get you close and then experiment. When it comes to cutting point grooves everyone wants them a little wider or longer so no one formula works. In 5 inch jaws two 1/8" shims would give 1/8" off set over 5 inches and 3/8" over 15 inches. I would say try that for a start, then adjust it.
 
Been a while since I posted this, but thanks for all of the tips. I managed to find some angles for the Vice, but after messing around with it for a while, I agree that using the vice is a major headache. Especially since 0 degrees on the vice seems off by a few degrees and then getting it locked in at the exact same position is nearly impossible.

I made up something similar to what you described. Flat piece running the length of the bed with 2 pieces underneath that fit perfectly into 2 of the slots on the table. Fixed the lathe bed to it with a single bolt at one end and then figured out all of my positions and drilled a whole at the other end of the lathe bed for a pin, so that I have a locater hole at each position. Then built some brackets to hold the lathe bed down at the other end to keep it from bouncing. Just 2 quick screws and a pin to move and I'm set up for another size.

Thanks again for all of the information. Not sure how long it would have taken me to come up with the solution on my own.
 
You must log in or register to reply here.
Back
Top