You do some really nice work Brian, i love these projects.

Alright, I had a chance to do a little bit on this project. I changed the shock towers slightly. I was going to try to make this work without a top plate on the bulkheads (just the shock tower) but have gone back to a top plate. Here's how it looks attached through the bulkheads with four 70mm bolts, that will go through holes in the chassis:

http://i779.photobucket.com/albums/y..._1211Small.jpg

http://i779.photobucket.com/albums/y..._1212Small.jpg

http://i779.photobucket.com/albums/y..._1213Small.jpg

The idea with this is that I'm not relying on any screws into the plastic bulkheads to hold things together. I decided to think of how I would want this designed If I were designing it from the ground up - and connecting the shock towers as directly to the chassis as possible was what I wanted. So I needed to design my own shock towers with narrower legs/feet with the same width as the bottom chassis holes.

Next, I need to start cutting/drilling the chassis so I can mount this.

Edit:

I'll add these comments to this post: The extra holes in the supports will allow me to lower the tower by 1/4" if I want to try raising the ride height a bit.

The diff blocks have been reinforced with glued-on lexan sheet because I had to drill holes through them - otherwise they would have broken into two pieces.

I'm a fan.
 

I'm a fan now. Your work is very interesting, and I like the way you think with regards to rigidity, strength, and stability. This rig is going to turn out really solid if you keep moving in the same direction you are right now. Keep up the good work Bud. It's too bad that there is not an easy way to replace the bulkhead/diff setup altogether. Isn't there an aluminum upgrade for those diffs?

Jerry, thanks for the kind words, and yes, you can buy aluminum bulkheads and shock towers - but I decided I'd rather engineer my own solution than just buy someone else's. I think that what I'm doing will be just as strong - so I'm giving it a try.

[Having said that, I do have one set of aluminum bulkheads and one aluminum shock tower on my other large scale build - but I picked them up at a bargain.]

I cut the back end of the chassis plate and mounted the rear bulkhead assembly to see how it fits:

http://i779.photobucket.com/albums/y..._1246Small.jpg

http://i779.photobucket.com/albums/y..._1247Small.jpg

http://i779.photobucket.com/albums/y..._1248Small.jpg

http://i779.photobucket.com/albums/y..._1249Small.jpg

It feels very solid to me. I'll make a skid plate to protect the socket heads sticking out the bottom.

I love your builds man. Get crackin' on it. I can't wait for the next installment.

Thanks - I'd love to have the time to get this thing built quickly, but I think this will be a slow build.

I've already done some work on the motor mount, so I might get that installed before too long a delay.

-brian

ya $20 was a steal they wand 70 for one twice that size
http://cgi.ebay.com/7075-T6-Aluminum...ht_1343wt_1139

That's a larger sheet, so still a good price - they sold out of the one I bought.

I really like your plan. And its never a bad thing having more 1717-powered custom RC trucks in this world:rules:

TG

I agree! I put together the rear diff tonight with some of these parts (and some others):

http://i779.photobucket.com/albums/y..._1133Small.jpg


So I can get it installed with the rear center cvd and see where the cd/motor mount need to go.

How are you cutting the aluminum?

why not some countersink bolts?

All by hand:

http://i779.photobucket.com/albums/y..._1259Small.jpg

Even the long 24" cut:

http://i779.photobucket.com/albums/y..._1040Small.jpg

:wink:

McMaster-Carr did not have M4 flat head bolts long enough - I needed these to be 70mm.

takes alot of patience there

Wow, so you wrapped a hack saw blade with tape and went to town huh? How long did that take?

mate! you really do have patience to cut your own alloy... and so perfectly as well!!!

Nice job!!!

Actually, I was able to use the regular hacksaw with a 12" blade for about 9" in from either side. Then the frame of the saw got in the way of cutting further. It was only the center 6" or so that I needed the blade with the tape handle. It took a little time and patience, but with practice, I've found that I can cut very straight with a hacksaw - its long straight blade can serve as a guide once the cut is started.

Well that's good to know.

Here's the motor mount I made out of 1/4" Al angle (1.5" x 2"):

http://i779.photobucket.com/albums/y..._0988Small.jpg

http://i779.photobucket.com/albums/y..._0994Small.jpg

http://i779.photobucket.com/albums/y..._0995Small.jpg

http://i779.photobucket.com/albums/y..._1004Small.jpg

http://i779.photobucket.com/albums/y..._1006Small.jpg

I drilled the slots so that I could use the range of pinion gears I calculated I might need with the 50t and 54t spur.

And here is the installation of the CD and motor mount:

http://i779.photobucket.com/albums/y..._1263Small.jpg

http://i779.photobucket.com/albums/y..._1267Small.jpg

http://i779.photobucket.com/albums/y..._1261Small.jpg

http://i779.photobucket.com/albums/y..._1274Small.jpg

http://i779.photobucket.com/albums/y..._1275Small.jpg

http://i779.photobucket.com/albums/y..._1278Small.jpg

I'm using the Muggy CD mount with 1/4" spacers underneath for clearance with the 50t or 54t spur gear.

Nice work Brian, it's looking good.

Nice work. Looks like you lucked out with the way the CD mounts have horizontal threaded holes so you could drill through the aluminum and bolt it up. Or was that planned? :)

Those are the holes to mount mechanical brakes (all CD mounts have them). Since I'm not using mechanical brakes for this build, they are very convenient for aligning and attaching my motor mount - I used them in the same way when I converted my Muggy with an Al-angle motor mount.

Brian- I did some cutting on 6061-T6 alu .250" thick yesterday. I used a Ridgid jigsaw (AC110 power) with a metal blade. This combination was great and cut through the aluminum like butter! Plenty of control on the blade, pretty perfect cuts too. Much better than my metal band saw.

Build is looking good so far too!! Love the Hummer body.

If I have to make another long cut I may have to pull my jigsaw out and pick up a good blade for it (I'll admit the long 24" cut with the hacksaw was not fun :wink:). For the small cuts I'm making now, I don't mind the hand saws.

Looking good it makes me want to order some aluminum For my own project

brian this looks very solid! nice work!

Just wondering... do you buy the alloy with the 90degree bend or do you bend it yourself ???

I think this is the same as what I bought a while back and has lasted me a few projects:

Edit: here's the right one:

http://cgi.ebay.com/6061-Alum-Unequa...item3350b209aa

I was considering a few options for what to make my battery trays out of - I think I'm going to use what I've used in a number of other vehicles:

PVC u-channel

The price I see on Amazon right now is very low - I bought a bunch when Amazon had it even a little cheaper. I want to fit these batteries in on their sides:

http://www.hobbypartz.com/98p-25c-4000-6s1p.html

and my 5s packs of the same capacity are 41.5mm tall (a little less than their specs). So I sanded down the inside of one leg of the u-channel with my dremel drum sander - and the 5s packs are a perfect fit:

http://i779.photobucket.com/albums/y..._1301Small.jpg


http://i779.photobucket.com/albums/y..._1302Small.jpg

I still need to cut slots for the battery leads and then I can lay them out where I want them on the chassis. I plan to run 2 6s packs in parallel.

I just ordered a pair of the Gens Ace 6s packs I linked to above - Hobbypartz has a bunch of their batteries on sale - these are 20% off - so cheaper than what I paid for my 5s packs.

Looking good. I'm loving the sturdy motor mount. I did something similar with the "feet" on the sides of the CD for my 10yr old nephew's Mayhem ST, just wish I had more room on that truck to make them bigger. It holds up to his bashing so I guess its ok. Hopefully this winter I'll get to start on my LST based 1/5th, till then I'll be watching and collecting parts.

How did you make your slots in the L channel?

I just drill a few holes with the drill press as close together as I can get them, then I use a file or dremel w/carbide bit to remove the rest of the material.

Cool thanks.

I've been considering purchasing a mill, but even for the small X2 benchtop size, I'm look at well over $1k for it and tooling. I wouldn't be using it often enough to justify the price. Finding ways to make stuff without it is my mission. You've definitely shown me a few things. Thanks

I hear you about the mill - I, too, can't justify that purchase for this hobby. So I've tried to do my best at fabricating parts with my limited tools - drill press, hack saws, files, dremel, etc. - by finding pieces of Al angle, u-channel, and sheet that fit my needs.

i too have cut many many things just with the hack saw. i built my SC truck completely with hand tools.

i found that when just holding onto the saw wearing a thick pair of work gloves on the saw hand works wonders for grip. and it also works better to flip the teeth and do the cutting on the pull stoke. since the blade is free it tends to bend a lot when pushing.

i also clamped angle stock to all my long cuts to keep straight lines.

I did some more work on one of my battery trays - they will have 1/8" Al angle at the front and back:

http://i779.photobucket.com/albums/y..._1371Small.jpg

http://i779.photobucket.com/albums/y..._1372Small.jpg

http://i779.photobucket.com/albums/y..._1384Small.jpg

I also finished the front shock tower - cut down feet, sway bar installed, mounting holes drilled and tapped for m4 screws:

http://i779.photobucket.com/albums/y..._1381Small.jpg

I saw those PVC channels you used and ordered some myself. The price sky rocketed after I ordered mine though.

I've seen the price go up and down dramatically on those channels - it's weird :neutral: