Wooden Rack and Pinion

[Bob Eustace]

Trying to make a wooden rack and pinion for a game scoreboard 48" high. Can make the pinions OK using the gear gadget in Aspire 3.5 (dropped in version 4?) BUT stumped with the rack! This doesnt have to be super accurate and movement is not critical as it just moves a pointer up and down vertically lining up with the numbers one to twenty one. Can anyone point us in the right direction please??? I realise we could use the wooden chain method but that has a heck of a lot of bits!

[adrianm]

Bob, you can find the gear gadget for version 4 along with other gadgets at this link - http://gadgets.vectric.com - click on Gadget Library.

[Bob Eustace]

Thanks Adrian but they dont have a rack yet??

[Simops]

Bob, there is a program you can buy online for $26 that calculates gears and racks......a rack is a gear unwrapped.....
http://woodgears.ca/gear/index.html

[Brian Harnett]

Bob, there is a program you can buy online for $26 that calculates gears and racks......a rack is a gear unwrapped.....
http://woodgears.ca/gear/index.html

Thats a great program, I have been using it for over a year well worth the money.

[Greencarvings]

Then just calculate out a large corresponding gear and then use the unwrapper gadget to unwrap the gear so you can cut it.

[jerry_stanek]

I was thinking the same thing but then realized that the teeth would be wrong as they would be to close together when unwrapped.

[mark_stief]

teeth should be right if you make a gear with the teeth on the inside then unwrap it or I could be wrong:eek:

[myxpykalix]

Bob,
I have the woodgears pgm and email me with your deminsions and i'll make you a file and send it...:D

[Bob Eustace]

Thanks Jack and to everyone that responded - much appreciated. Unwrapping never entered my feeble brain! Did learn though that the Aspire gadgets now import to version 4 and install is now idiot proof. You simply download and click. No unzipping and hunting for a folder buried deep inside! Nice one Vectric!

[gc3]

..........

[gerryv]

I'm with Jerry on this one. Unless the program is written to adjust the profile when it's unwrapped, the pinion teeth won't likely fit into the rack. Maybe an email to the author?

[Brian Harnett]

If you give me the info on how many teeth you need on the sprocket and rack I can send you a dxf file.