Stepdown for Turning a Blank

[jdervin]

I'm using the Indexer Design tool [TI] to turn a blank, with a .25" stepdown on a 1.416" rough blank and a goal of a 1" finish pass. When I make the cutting file, both passes cut at 1" (meaning that my first pass is trying to remove .416" of material in one go). Shouldn't the first pass be at 1.166?

[jim_stadtlander]

John,
I tried your numbers, and I get the same results. Don't know why. I have used this utility tool once in awhile and sometimes it gives out odd results like this time. I tried changing your rough dia to 1.75 and it cuts in three passes. Also tried your dia of 1.416 and changing the step down to .125 and it does it in three passes. Using this utility, your last roughing pass is always at the dia of your finishing pass. I always thought this was a bit strange and that the last roughing pass should be above the finishing pass by a small amount.

[jdervin]

I've been talking with Frank at SB tech support and he says they're looking into it to see if something might be wrong with the utility.

[bill.young]

Hi John,

I've done some work on the Indexer Virtual Tool and think I've resolved the stepdown issue. If you want to try it out before the next software release and help test it out, you can download it at http://www.shopbottools.com/LabFiles/sb_labs_files/Indexer_Virtual_Tool_07_05_09.zip

Just rename your "C:\program files\ShopBot\Virtual Tools\Indexer" folder to something like "Indexer_old"...just in case...then unzip the downloaded file and plunk that "Indexer" folder into your "Virtual Tools" folder. You should be good to go.

Bill

[jdervin]

I've been testing the 07_05_09 indexer tool (version 2.2.2) and so far, everything seems to be working fine. I am assuming that if stepdown is not an even multiple of the final depth, then the final depth is divided evenly between each step, up to, but not exceeding the stepdown.

For instance: if I have a starting radius of 1, a -0.5 depth of cut, and specify a .2 stepdown, I get three steps of .167

0.8333333
0.6666666
0.5

instead of two at .2 and one at .1

0.8
0.6
0.5

Is my assumption correct?