Cutting Gears

[ADDAndy]

Hey,
Been a while since I've been on here.
What machine would I need to be able to cut gears? Would a verical mill with a rotary table work? I'm looking around for something that will cut them. If you know please tell me and add links if possible

 

[Plaidfish]

What do you need cut...I'm in the process of laying out a c-n-c Cadd file for a chassis and Spur gear adapter...

 

[ADDAndy]

I would like to make the transmission on this site http://home.tiscali.nl/iliyacerjak/gearbox.htm , but also want the ability to make any gear that I need, since i go through them in my T-maxx often.

 

[Plaidfish]

Woah man you need to seek serious psychiatric help for that stuff.....making precision gears is definately something that's worth buying unless you have a machine shop at your disposal.....you could always use manual tools but the time will be just insane for gears.....what exactly are you trashing on your maxx...cause I've set plenty of them up and never really had shredding issues w/ gears unless the mesh got screwed up.....

 

[Lessen]

dang, and I thought my CAD endeavor was steep. Gears have to be super super super precise, the mathematics behind the design of a gear are crucial to there usability and life. unless you seriously plan on using the tools to do a lot of other stuff I'd just keep buying new gears. I'm starting to learn a little bit about CAD so I can do CNC stuf someday at home, not something I expect even within 5 or 6 years from now but eventually

 

[Plaidfish]

How much have you learned so far?

I just finished my first draft of my upper Chassis...I can't wait to get to work and print out my rough draft.....I need sleep now...between my kid and the new scooter rides all weekend, Taking her to see seeing Fat Albert, Helping father Clean Yard, Cleaning the House and this drawing and de-decorating...I'm beat.....I get up in 5.5 hrs.....

 

[Lessen]

just the basics, some terminology, setup, what layers are for... yadda yadda yadda. I don't sit with it everyday though. Just every here and then I'll review what I read and stuff. It's a long road and I'm in no hurry.

 

[Plaidfish]

yeah it's a long road ahead...just think of it like a stack of clear sheets that you can draw on......I tend to keep things simple.....give me your e-mail address and I can send you my rough draft on that chassis plate....give you something to play with and rip it apart....I took the day off of work so I could get more stuff done on it today...I need to go buy some cheapo plastic parts for something to measure.......am I now in the obbsession category of a hobby?????...I'm actually hoping to get this set up like a kit for others to use if they are interested......I'd love to have a hobby that paid for itself and then some......but then it would be work and I'd grow to hate it.....LOL...I'd deal w/ it......L8R...off to the LHS.......

 

[ADDAndy]

I'm pretty good with AutoCAD, just need to know what i need before I go spend money on a mill that dosen't do what I want it to.

 

[Plaidfish]

DO you know how to create a gear in Autocadd?
I thought I could get by w/ an adapter plate and it looks like I need a 1 peice gear for my project.....I know there's an easy way to create them in ACADD....I just don't know it...

 

[Lessen]

what vehicle are you designing a chassis plate for? Send it to [email protected] I could use something to play with.

 

[ADDAndy]

I can make a gear in ACAD.

 

[Plaidfish]

How?.... or even better yet if I send you a dimension drawing can you lay out the outergear (the teeth) for me?...I can finish the rest from there......

 

[scottm]

OK, the profile of a gear is an involute curve. Do a search on involute or involute gear. The tooth profile is caluclated for each pitch size and number of teath. I don't know if regular autocad can do it. Here is a link describing how it works:

http://www.cadquest.com/books/pdf/gears.pdf#search='involute%20gear'

Gears are normally cut with a gear cutter tool on a "hob" which is a gear cutting machine. You can't do it with a manual mill because the gear cutting tool doesn't make the profile, the hob machine moves the gear blank around against the cutter. So to make gears you have 2 choices: go to a gear shop with drawings of what you want and be prepared to spend a lot of money. Custom work is very expensive, plus the steel required is expensive, then it has to be heat-treated for strength. Or you can draw accurate involute gear profiles in a cad program and cut the gears out on a profile cutting machine, like a laser. That is how we make the tool steel spur gears at RC Solutions. I use Pro/Engineer for cad, and here is the procedure on the Pro/E website:

http://www.ptc.com/appserver/it/icm...extimg/main_v.jsp?im_dbkey=8310&icg_dbkey=382