Indexer set up

[marcrunner]

Hello,
I recently became the owner of a PR96. THe unit came with an indexer that I would like to implement into the system. I have chosen to mount the unit on the Y axis. Because of the way the cross supports are layed out on my table, I only have 8" of travel from the end of the last cross support to the end of the X axis travel on my machine. So my question is, Should I assemble the indexer so that my horizontal center line is at the end of the X axis travel or split the difference between this and the last cross support? Does that make any sense at all? THanx, Marc

[rcnewcomb]

I'd try to go closer to the end of your X travel.

You will aslo want to set up a custom cut to move your router to the indexer origin for easier setup.

[myxpykalix]

Actually I would disagree with Randall on placement for this reason. Lets say you have a 10" wide X 3' long square column that you want to flute. By placing it close to your end of X travel you in essence limit the width of stock you can cut because it can't travel to the furthest point on the material in X.

Mine is a custom table mounted in the X so i'm not familiar with your table. If you look at some of the previous posts in this column you will see where others have mounted thiers in the Y off the back of their bed sucessfully. I don't know what clearances that gives them in terms of max diameter they can turn but in reality most things you would want to turn like table legs, balusters, ect. should be no problem.

Bottom line is the centerline distance from the end of X will also be determined by the height of the headstock center to the top of the aluminum track and my guess is that is it somewhere between 4" and 6".

[jim_vv]

Marc,

Keep in mind that if you mount your indexer on your table your turning radius limit will be defined by the Z travel your machine. The center or the indexer is going to be roughly 6" off of your table if you bolt it to the table. I have a PRS 9648 with 8" of Z travel. If I had known, I would have ordered a machine with a 12" Z. I built a table and mounted my indexer off of the end of my machine so that I could get the most out of my Z. I can turn up to 10 inches round.


3107

Kind Regards,

JIM

[rcnewcomb]

My indexer is mounted similar to Jim's.

Jack brings up a valid point. How do you intend to use the indexer? That will influence your decision.

And the joy of a Shopbot it that you can always modify it later.

[marcrunner]

Thanx for all of the help guys. I would prefer to do what Randall says, but am afraid I would be safer with what Jack posted. I guess that is my question, because I have no real world experience with this, It is hard to calculate exactly how far out I can mount the indexer. Do you find that when you have an object to mill, that it is always "attacked" parallel to the Z axis? Or are their times when I would need the extra travel that I am afforded if I mount the indexer closer to the support brace allowing me to "pass" up the indexer on the X axis?

[marcrunner]

Jim,
Also another good point I didn't think of. Yes I have a standard 6" of Z travel. So if I am understanding this right, No matter how low I mount the indexer, I can only mill up to 6" before I run out of Z. So I guess the best case scenario is to mount the indexer so I will have full Z travel. As far as the X travel is concerned, I just need to figure out whether I will be doing more projects that focus on Z travel(spindles) or projects that focus on milling objects that require a broader X travel. Hopefully this makes sense. I guess I am just chomping at the bit to finish this part of my system.

[oddcoach]

You need to measure the swing of the lathe. That is how far you ned to mount the indexer away from the table. Otherwise you will limit its capacity. I have the center of mine about 1/4 inch away from my limit switch in the x direction. you don't want to worry bout hitting it in the middle of a file. you don't want to know how i know this. I also built a riser block on my indexer to get some extra swing, and mounted the center of the lathe a little below the top of my table so i don't have to worry about running out of z on large turnings.
John

[oddcoach]

here is a link to a previous post with some pictures
http://www.talkshopbot.com/forum/messages/33571/43053.html?1245897845