02-07-2006 15:57

=Martin=Taylor=

Re: pic: Crabstyle

Is the entire module made from one large piece of tubing?

Nice work.

02-07-2006 16:12

Joe_Widen

Re: pic: Crabstyle

Yeh. Its 3x3 aluminum square with a 1/8" wall thickness. The two horizontal plates will be welded on there.

03-07-2006 13:22

RogerR

Re: pic: Crabstyle

Question: if those two horizontal pieces will be welded on, then how do you get the shaft for the wheel into the module.

03-07-2006 13:35

Jeff K.

Re: pic: Crabstyle

Nice design, it looks hella cool. lol-I still have the nor-cal in me

Hmm..I think standoffs to hold the plates together would make it easier to work with and maintain instead of welding it to make a box. Although, you may have to increase the wall thickness to say, 3/16" or maybe 1/4" just for safety.

I'm wondering, what do you have it geared at? What is the pitch of the gears, and the first stage of reduction?

03-07-2006 17:03

Joe_Widen

Re: pic: Crabstyle

"Question: if those two horizontal pieces will be welded on, then how do you get the shaft for the wheel into the module."

Thats a good question. I didnt think of that. I can always attach the bottom plate with L pieces and screws.

"I'm wondering, what do you have it geared at? What is the pitch of the gears, and the first stage of reduction?"

They are 20 pitch gears. Its a 10-1 total reduction. The first stage is 5-1 and the second is 2-1.

03-07-2006 17:45

Cory

Re: pic: Crabstyle

With only one CIM per module, you should be able to get away with 24 or even possibly 32 DP gears, significantly lightening the module.

03-07-2006 18:18

Joe_Widen

Re: pic: Crabstyle

Well its 3/8" face width and as of right now I have and extra 1/10 of an inch on either side of the second stage reduction between the first gear and cim. Heres what the inside looks like. O yeh, I dont know how I'm doing the shafts so I made it simple for now.

PS, I'm not exactly sure how to check the mass on Inventor 11.

03-07-2006 19:26

sanddrag

Re: pic: Crabstyle

For weight, go File>iProperties then to the "Physical" tab and click on a requested accuracy from the dropdown menu. Make sure the materials are set on all your parts (same menu/tab). It has been pretty much the same since at least Inventor 5.

03-07-2006 19:54

Jeff K.

Re: pic: Crabstyle

Like, Cory said, I think 20 pitch for the first stage is a bit overkill, and you might be able to get away with using 24 pitch.

I'm not sure what type of bearings you are using, but you can't go wrong with flanged bearings.

Did you add any space between the gears in the C-C distance? A 0.001 or 0.002 wouldn't hurt.

03-07-2006 23:06

Joe_Widen

Re: pic: Crabstyle

This is really the first time I've ever made anything in Inventor. The weight of the whole module gears included is "2.962E+000 lbmass" according to inventor in "Very High" Accuracy


Well, since the gears cant get any smaller, I dont know of any advantages of using 32 pitch or 24 pitch since the gears cant be any smaller (I'm using 3/8" face width).

I love flanged bearings too, adn yes I'm using them

I dont have extra space right now, but there will be in the final version.

04-07-2006 00:30

Jeff K.

Re: pic: Crabstyle

Oh, so the distances for clearances with 20 pitch is good and if you were to design with a smaller gear for pitch such as 24 or 32, some things would interfere?

04-07-2006 00:40

Joe_Widen

Re: pic: Crabstyle

Yeh, exactly.