e's ExMT

[ekd]

Good, hard #s on axle and bond strength can now be had here.

The dyno is in line.

 

[ekd]

What are the ODs of the bearings used in Axial and Venom knuckles?

 

[monkeyracer]

What are the ODs of the bearings used in Axial and Venom knuckles?

The axial uses at 5 x 11 x 4 outside and a 10 x 15 x 4 inside bearing.

 

[ekd]

The axial uses at 5 x 11 x 4 outside and a 10 x 15 x 4 inside bearing.

Thanks.

I'm trying to find something I can set 8 x 12 bearings into. I figured out an aluminum C for T's rig that isn't quite so bulky looking on 2.2s.

Looks like I'll have to make the knuckles too. I have an odd idea left over from when I thought we might need double UJs.

 

[monkeyracer]

Thanks.

I'm trying to find something I can set 8 x 12 bearings into. I figured out an aluminum C for T's rig that isn't quite so bulky looking on 2.2s.

Looks like I'll have to make the knuckles too. I have an odd idea left over from when I thought we might need double UJs.

Why not put a 12mm bore in the outside and a 16mm bore in the inside of the knuckle for the bearings to seat in? Probably easier than making a whole new knuckle.

 

[ekd]

That's a good idea. The Mad knuckles don't have quite enough meat to do this, but the Axial or Venom might. Especially the Aluminum parts.

If you think the Axial could handle it, pls LMK? If this will work, I'll make cutters to keep it easy and quick.

Thanks, M.

 

[monkeyracer]

That's a good idea. The Mad knuckles don't have quite enough meat to do this, but the Axial or Venom might. Especially the Aluminum parts.

If you think the Axial could handle it, pls LMK? If this will work, I'll make cutters to keep it easy and quick.

Thanks, M.

The axial aluminum knuckles can handle .5mm taken out of the radius of the bore. The only issue I can see is the larger bearing (8 x 16 x 5) is usually 5mm thick...

 

[ekd]

Yup. That single mm is all the knuckle has to boss the bearings. Oh well.

I'm going to go forward with a C and knuckle set with precision and a minimum silhouette. Could be a while... and won't be cheap. Lot's to play with here.

Doing a lot of experiments here, and might have an upgrade for the truly thrifty among us (Don's ears just burned a bit..."thumbsup").

Edit: VXB stocks 8x16x4 bearings, at 2-5 times the cost of the 5mms. Hmmm.

 

[ekd]

By the time these are straightened internally, the flange is badly angled. Time for the lathe, or...

I'm going to see if I can make a mandrel that presses the flange perpendicular to the bore as it cools.

 

[ekd]

This is going to work. It produces superb stubs, and when I can afford a ton of these, I'll hunt down the balance between memory and heat/time periods, to speed the process up with an eye to using the tubes intact. It's a fine line... This stuff has strong memory. It's stout, and I think there is weight to be lost by shaving a bunch off.

The mandrel aligns the C, the outboard bearing pocket, the bore, and the flange. It doubles as a turning (OD) mandrel. I'm working on a precisely repeatable, quick clamp using a knockoff ViceGrip.

 

[asw27x]

looken good bro keep it up

 

[ekd]

looken good bro keep it up

Thanks.

I ran out of Mad tubes to mess with, but got some nice stubs out of the little pile I had. I got into this because I recently got some parts that were bent enough that facing the flange took out almost too much, by the time the flanges were right.

These parts have enough memory that I still have to face the flanges (1 very light cut) to get them perfect. I'm convinced they can be reformed to spec, but will need an IR thermometer, and a convection oven with a timer. There is a fine line between fully compliant and melted, and my current toaster oven is too small and inaccurate to sneak up on that temp consistently. Cooked off a few so far...

I'm happy with the stubs I'm getting. I'll try for speedy and cheap later, when there isn't more important mini tooling waiting for cash.

 

[ekd]

The Rock Hawk will be here by next weekend. A sent a teaser, and I couldn't be happier with the direction this is going.

 

[ekd]

As the Hawk will eventually be accidentally left on (there will be kids driving it), I intended to make it take a standard stick battery. The chassis I've been using as a template showed me that there is no way to do this, without ruining the handling, so... I ordered some NiMH AA ("3000" mAh).

Any thoughts or suggestions?

 

[Abavuso]

As the Hawk will eventually be accidentally left on (there will be kids driving it), I intended to make it take a standard stick battery. The chassis I've been using as a template showed me that there is no way to do this, without ruining the handling, so... I ordered some NiMH AA ("3000" mAh).

Any thoughts or suggestions?

You could run the NIMH pack along the bottom of the chasssis and then use a piece of lexan between the chassis brace to mount the eletronics in the cab area, that should work nice for you.

Since you're planing on sizing this down to a 2.2 size you could mount 2 cells on the chassis 2 on the front and 2 on the rear axle... it might be kinda perminent that way and have to charge the pack in place but for the kidos it would work just fine. That is if you are going to make your own pack.

the chassis is 52 mm wide to the inside of the plates if that helps you with your planning.

 

[monkeyracer]

As the Hawk will eventually be accidentally left on (there will be kids driving it), I intended to make it take a standard stick battery. The chassis I've been using as a template showed me that there is no way to do this, without ruining the handling, so... I ordered some NiMH AA ("3000" mAh).

Any thoughts or suggestions?

I think that if you can mount them all on the axles, that would be the best for weight distribution. The downside to AA NiMH's would be the current draw capability, so you will definitely see some power loss, especially when bound up.

 

[ekd]

You could run the NIMH pack along the bottom of the chasssis and then use a piece of lexan between the chassis brace to mount the eletronics in the cab area, that should work nice for you.

Since you're planing on sizing this down to a 2.2 size you could mount 2 cells on the chassis 2 on the front and 2 on the rear axle... it might be kinda perminent that way and have to charge the pack in place but for the kidos it would work just fine. That is if you are going to make your own pack.

the chassis is 52 mm wide to the inside of the plates if that helps you with your planning.

You're right, a second deck will give me lots of options. And there is no need for replaceable packs, the kids can wait a few mins for more fun... and a cool down period won't hurt a thing.

I think that if you can mount them all on the axles, that would be the best for weight distribution. The downside to AA NiMH's would be the current draw capability, so you will definitely see some power loss, especially when bound up.

This won't be comped, and if it won't pull out of a bind... the kids can run up and save it. Beats breaking something with the trigger... and they have, apparently, unlimited energy and mobility (lucky little bastids).

If the kids end up with their own crawlers, T will get stronger batts if she wants them. I'm very interested in seeing what AAs can do. They are a great size for manipulating weight distribution. We'll see.

 

[BentMetaL]

You're right, a second deck will give me lots of options. And there is no need for replaceable packs, the kids can wait a few mins for more fun... and a cool down period won't hurt a thing.

This won't be comped, and if it won't pull out of a bind... the kids can run up and save it. Beats breaking something with the trigger... and they have, apparently, unlimited energy and mobility (lucky little bastids).

If the kids end up with their own crawlers, T will get stronger batts if she wants them. I'm very interested in seeing what AAs can do. They are a great size for manipulating weight distribution. We'll see.

Eric, how about using 1 2 cell 850 on the front strapped to your servo. That's how my son does it on his AX-10.

 

[monkeyracer]

Eric, how about using 1 2 cell 850 on the front strapped to your servo. That's how my son does it on his AX-10.

He wants to stick with Ni batteries since they will be operated by kids, who often forget to turn the crawler off, and lipo getting discharged below LVC is not a good thing, Nickel batteries are much more forgiving at low voltage.

 

[BentMetaL]

Oh okay I see said the blind man. I did read the kid thing and that's true. My grandson will run it until it's completely dead.