Anyone know anything about sprockets?

[JoyMonkey]

I'm working on a 4/8way switch that will integrate well with the CP I'm planning, but I'm no engineer and haven't got a clue what kind of sprockets I'll need. I was going to CNC the sprockets today, then I realised that I have no idea what I'm doing  

So here's a quick idea of what I need to know. The small green sprocket needs to turn the large red sprocket. The diameters need to be in or around 1" and 3.125".

Anyone know how it'd be done? I'd rather not use a belt as I think it'd make things much more complicated than needs be.

[JoyMonkey]

And here's a full size PDF drawing...

Does anyone know;
how many teeth should each have?
and what depth should the teeth be?

[SirPeale]

This is the time on Sprockets when we dance!

[wj2k3]

See page 946 of McMasters catalog for some information.  You may even find the gear you need straight from them.

[JoyMonkey]

See page 946 of McMasters catalog for some information.  You may even find the gear you need straight from them.

Its funny, I tried looking through McMaster online before I posted but couldn't find anything. I have a catalog sitting on my desk, maybe I should take some time to go over it...

What I really need is a drawing of two sinterlocking prockets similar is size to what I need, so I can make myself.

[OSCAR]

I drew 24DP, 20deg pressure angle spur gears for you.

The 1" PD spur will have 24 teeth, and the 3.125" spur needs 75 teeth.  Your CNC can accept DXF, right?  The calculations for proper tooth profile are pretty involved to ensure proper meshing, so it would be best if you can import my DXF directly without trying to redraw it, if possible.

Good luck!!

[OSCAR]

Oops, can't upload a DXF on the board.  Email me at oscar_controls@yahoo.com and I'll send you the DXF directly.

[NoOne=NBA=]

Oscar,

The workaround to that seems to be to change the filename to .txt, and THEN post it.
Someone else did that the other day, and it worked fine.

[JoyMonkey]

Wow! Thats exactly what I need! Thanks again Oscar!
(email sent)

[OSCAR]

I thought about that, but I wasn't sure if uploading the file in ASCII would corrupt the file.  Cad files are funny, sometimes even translating them can cause scaling issues.  And since the spur gears are drawn exact to scale, I didn't want them screwed up in the event of some weird ASCII translation.

[OSCAR]

JoyMonkey - you should have the file now.  Let me know if you need any more help with this.

[Mameotron]

Wow, Oscar, that's really awesome.  Do you have a design program, or are you just that good with AutoCad?

How expensive is it to machine your own sprockets?  I think that's awesome, considering the whole build your own concept here.

Another place to look for sprockets:

http://bostongear.com/products/open/sg.html#

They have a supplier where I live, and I can say their quality is really top notch.

[danny_galaga]

when looking for these, be sure to look for GEARS, not sprockets. that might be where you were having trouble finding what you wanted. sprockets generally are designed to drive chains, like on a bicycle. gears normally drive each other...

[F1r3f1ght3r]

This is the time on Sprockets when we dance!

 

[Howard_Casto]

lego technics..... those gears rock!  And all you have to do is raid your old toy chest.