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BigBoy1
01-07-2009, 08:31 PM
I need to replace a 32 tooth gear and will need to make it. I do not have a dividing head. My question, can the rotary table, mounted vertically, be used to do the spacing of the teeth? For 32 teeth, each tooth increment would be 11.25 degrees. If the table rotation is in one direction only, back-lash will be eliminated. Appreciate any help. Thanks.

Bill

Teenage_Machinist
01-07-2009, 08:33 PM
It can. Also many tables take dividing plates or you can make your own. You will want to lock the table.

SGW
01-07-2009, 08:35 PM
Sure - it should be fine.

It may help to calculate and print out a table of values ahead of time to help keep track of where you are.

alanganes
01-07-2009, 08:55 PM
Sure - it should be fine.

It may help to calculate and print out a table of values ahead of time to help keep track of where you are.


The easy way to do that (if you are not aware of this already) is to go here:

http://www.myvirtualnetwork.com/mklotz/#shop

and download the program called "ROTARY.ZIP" by Marv Klotz. It produces a nice table of settings for your rotary table that you can print out and have by your mill when you do the job. A great selection of other very clever and handy software there as well, that Mr Klotz shares freely.

-Al

Rich Carlstedt
01-07-2009, 09:45 PM
Hint
When you do it, mark each place you stop on the rotab with a magic marker.
ie 11.25, 22.5 etc.
That way if you have to repeat for any reason, you will find it easier.
When done, some alcohol will remove all the ink.

You may also wish to fasten a 3 jaw chuck to the Rotab, so you can
get your spindle closer to the work when it is held in the 3 jaw.
Rich

oldtiffie
01-08-2009, 02:51 AM
Courtesy of Marv Klotz' "Rotary" utility - done - just print it out - your choice of decimal degree or deg.min.sec on each line:

Number of divisions = 32

DIVISION degdec deg min sec
0 0.0000 0 0 0
1 11.2500 11 15 0
2 22.5000 22 30 0
3 33.7500 33 45 0
4 45.0000 45 0 0
5 56.2500 56 15 0
6 67.5000 67 30 0
7 78.7500 78 45 0
8 90.0000 90 0 0
9 101.2500 101 15 0
10 112.5000 112 30 0
11 123.7500 123 45 0
12 135.0000 135 0 0
13 146.2500 146 15 0
14 157.5000 157 30 0
15 168.7500 168 45 0
16 180.0000 180 0 0
17 191.2500 191 15 0
18 202.5000 202 30 0
19 213.7500 213 45 0
20 225.0000 225 0 0
21 236.2500 236 15 0
22 247.5000 247 30 0
23 258.7500 258 45 0
24 270.0000 270 0 0
25 281.2500 281 15 0
26 292.5000 292 30 0
27 303.7500 303 45 0
28 315.0000 315 0 0
29 326.2500 326 15 0
30 337.5000 337 30 0
31 348.7500 348 45 0
32 360.0000 0 0 0

oldtiffie
01-08-2009, 05:11 AM
.........................
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If the table rotation is in one direction only, back-lash will be eliminated. Appreciate any help. Thanks.

Bill

That's true so far as it goes Bill. That will position the job on the rotary table ready to start the cuts.

Once the cut starts the table can "rattle around" in the combined back-lash between the worm and worm-wheel as well as the "end-float" of the worm spindle.

"Standard (compulsory actually) practice" in my days "in the shop" (and here too) is to use the table clamps and clamp the table as soon as it is positioned, take the cut - "full-depth" or minimal number of cuts - withdraw the cutter, then unclamp, reposition the job for the next cut, then clamp, then cut etc.etc. and you will get a better cut and not knock the cutter, the table or the job around.

Don't hurry - "hasten slowly".

ahidley
01-08-2009, 10:32 AM
http://i194.photobucket.com/albums/z80/ahidley/5CuttingGearTeeth1.jpg
http://i194.photobucket.com/albums/z80/ahidley/5CuttingGearTeeth1.jpg

http://i194.photobucket.com/albums/z80/ahidley/2CutGears1.jpg
http://i194.photobucket.com/albums/z80/ahidley/2CutGears1.jpg