pic: Dual FisherPrice Gearbox

[Pavan Dave]

Originally Posted by Cory

I think it'd be best to have the water jet cut it like 0.010 under and then ream the hole.

Whenever we get waterjetted parts the holes are usually clearance holes or tap drill holes and their diameter is not critical. Our guy cuts them slightly undersize then we open them up with the correct size drill.

I know Pink just cuts them slightly undersized and then anything that needs a bearing in it gets opened up with a reamer in a hand drill. I'd never have guessed you could get away with using a hand drill, but it sure works for them.

We also have the water jet cut them slightly undersized and ream them out. I can remember one instance where I failed to do so on a part and we ended up having to put a nut on the other end due to the hole being to big to tap with the bolt that we wanted to place in there.


Pavan.

[vivek16]

Originally Posted by Aren_Hill

any particular reason you couldn't just run a NBD setup in 1st gear? that'll get you a 47:1 reduction and would be faster and easier to make.
The only difference being orientation as the NBD setup would be longer and skinnier.


edit: nevermind just read the title this is for two... whoops, but you could just run two setups or 2fp's into one dewalt
http://www.chiefdelphi.com/media/photos/20145
http://www.chiefdelphi.com/media/photos/19245

...

That is a good idea. It would be much cheaper and lighter.

thanks, Vivek

[AdamHeard]

Originally Posted by vivek16

...

That is a good idea. It would be much cheaper and lighter.

thanks, Vivek

Made me realize a completely COTS solution to getting ~ 48:1 from two FPs.

Two FPs into AndyMark planetaries into a toughbox yields a 46.8~1 reduction.

I know it's not the lightest, but It requires no machining or work besides assembly (and the FP pinion).

[vivek16]

Originally Posted by AdamHeard

Made me realize a completely COTS solution to getting ~ 48:1 from two FPs.

Two FPs into AndyMark planetaries into a toughbox yields a 46.8~1 reduction.

I know it's not the lightest, but It requires no machining or work besides assembly (and the FP pinion).

Adam,

I thought about that a while ago and ruled it out because it was too heavy. We are pretty concerned about weight.

How much does a prealtered dewalt gearbox assembly weigh?

If it is less than 2 pounds, it just may be worth it.

thanks, Vivek

[vivek16]

Well, I altered the gearbox and added Idler sprocket mounts.
Here are a few pictures:
http://i200.photobucket.com/albums/a...INALRENDER.jpg
http://i200.photobucket.com/albums/a...i/DSCN7920.jpg
http://i200.photobucket.com/albums/a...i/DSCN7921.jpg

The first ones a render, the second two are of its construction so far.

thanks, vivek

EDIT: disregeard the messy desk behind the partially completed gearbox.

[acdcfan259]

Originally Posted by vivek16

EDIT: disregeard the messy desk behind the partially completed gearbox.

Messy, you don't even know messy.

[vivek16]

haha, tell that to our mentors. We want an aluminum magnet purely for the purpose of picking up filings off the carpet.

I agree, that's the cleanest my desk's been in weeks.

I'll finish the gearbox on thursday hopefully. I couldn't get the gears off the fps so I'm going to go over to the auto body shop next to our workshop and ask to use their nut splitter. Maybe having broken fp gears will intimidate the next fp gears we try to get off to come off easier.

-Vivek