Making a Rack & Pinion

[John Stevenson]

Arnak,

No problem if you wnat to make one. The profile for a rack cutter is straight sided with an angle of 14-1/2 degrees or 20 degrees depending on the type.

As someone else has pointed out you could use a tapered slot drill or end mill if you can get the correct taper and tip size.

This will be the stumbling block in getting those two to match. Tapered end mills are available off the shelf J&L do them from 1 degree up to about 12 in ones then the tend to go in 2's or 5's.
Only snag is with these the tips are about 3/32 or 1/8", OK for doing a 10DP rack but not a lot of good at myford size levels.

Again you can cheat and make a home made one.
You can even use a 'D'bit if you mill the bulk out first.

Here's one I did earlier



This was a "get John out the sh*te job" brass helical that needed to be done whilst a new one was ordered [ in fact it's still runing from 3 years ago ]
Milled on a 4th axis on the CNC but besides that it proves that a simple 'D' cutter turned up with a form button will work.

John S.

[Bond]

Just a thought but boats use a rack & pinion you can go to boat salvage.

[Allan Waterfall]

<font face="Verdana, Arial" size="2">Originally posted by Carl:
If you have access to a lathe with a good size center to center dimension, maybe you could mount the cutter centered on a long arbor between centers and mount the rack stock on the cross slide at the proper height to give proper depth of cut.

Lock the carriage and take the first cut. With a dial indicator on the carriage, unlock it and use the indicator to move the carriage the correct distance for the next cut. Lock the carriage and take the second cut. Repeat as needed.</font>

Something like this?
http://bbs.homeshopmachinist.net//Fo...ML/010482.html

Allan

[Arnak]

Hi Guys,

Thanks for all the great suggestions and brilliant photo's.

I should have enough info there to get started now!

Arnak

[Al Messer]

Arnak, I'd vore for using the Shaper, if you have access to one.