MAZ 543 8x8 multi-axle build

[ecoli]

Greetings comrades

I haven't done a build in a while, and have always wanted a multi-axled rig and suddenly found myself with a bunch of axles, trannies and other miscellaneous needed parts to do one. Started looking around the net for inspiration and came across the MAZ trucks, originally built for the Russian military:

Some more pics here:

http://www.oldrussiancars.com/archives/tag/8x8/page/2

Wikipedia entry:

http://en.wikipedia.org/wiki/MAZ-7310

Essentially, built in the 1960s developed by the Minsk Auto Plant for the Russian military. It was used primarily as a heavy duty transporter, and as such came in a number of different configurations (mobile Scud missile launcher, flatbed, crane, etc.). The most distinctive part of the vehicle is the twin split cab up front, which really caught my eye. The MAZ was probably most famous (infamous) for the Scud missile configuration which was used by the Russians but also in Iraq.

Surprisingly, when I've taken a look on the interwebs, I haven't seen any rc build threads, although there could be some on an obscure Ukrainian web site somewhere :mrgreen: Dragon does have a static model of the MAZ 543 which I may just have to buy to get a better idea of some of the additional details.

As for the build, using Axial axles and tranny with Tamiya hummer rims and RC4WD flashpoints. Electronics will be a mix of what I have lying around. The rest will be pretty much all scratch made components as most multi-axles builds are, so don't expect daily progress updates :mrgreen:

A big thanks to Sloppy for answering a lot of my questions I've had on multi-axles builds to date. Also borrowed several ideas from VForce's HEMTT build. This should be interesting.

 

[ecoli]

Ok, so where I stand now. I've basically got it up to roller status. The leaf spring packs were made from fish tape I picked up at Home Depot (thanks again for the tip Sloppy!)

Fish tape is typically used for running wires under carpet or behind drywall. $15 for 25 feet of it. I've used about 10 feet of it for making the leaf spring packs!

All of the parts are more or less rough cut, so excuse the ghetto zap strap set-up. My plan is to get everything roughed out, including the cab, for the summer, figuring out needed modifications, and then drawing all the metal plates, etc. in CAD and sending to my laser cutter to do up for me. The fall/winter will be used to build a final detailed out cab. At least, that's the plan !

In the meantime, some pics of where it stands as of today:

 

[alan]

Nice! I'm loving this whole multi-axle craze lately!

 

[ecoli]

Nice! I'm loving this whole multi-axle craze lately!

Thanks. Yeah, it seems like a lot of folks are getting bitten by the bug. Maybe there'll be enough out there one day to have European style trials closer to home The great thing is seeing what others are doing and learning what works/doesn't work for these rigs. The learning curve is very steep with building multi axled rigs!

 

[pardonmyn00b]

I got bitten by the multi-axle bug myself, but its effects wore off before I could finish the cab. This might just spark my interest in it again. Lookin' good so far

 

[SlowKrawl]

This should be an awesome build chris, chuck a body on it and lets hit the trails! Somewhere on my to-do list on a multi-axle rig, but it might be a while haha.

 

[ecoli]

I got bitten by the multi-axle bug myself, but its effects wore off before I could finish the cab. This might just spark my interest in it again. Lookin' good so far

They're definitely cool rigs. I just hope my rc ADD doesn't hit before this one is finished

This should be an awesome build chris, chuck a body on it and lets hit the trails! Somewhere on my to-do list on a multi-axle rig, but it might be a while haha.

With a bit of luck, I should have this in running condition by next weekend. It'll be a long time before it's "finished", but thats what our winters are for, right ?

 

[ecoli]

Man, these multi-axled rigs take a long time to make any progress! Almost have it to running status, just need the steering links sorted out. Some pics:

Picked up a small sheet of styrene ! 4' x 8' sheet, should hold me for a while. Paid about $34 for the sheet from an industrial plastics company. Don't go to the hobby store if you're just getting plain styrene!

Set-up the driveline. Decided since I had extra Axial trannies, to convert one to a t-case.

Made a cradle for the t-case. It's still sitting a little high, driveline angle isn't great. The final version I'll probably drop it down another 1/2" or so.

For steering, I decided to go with a dual servo set-up connected to a y-connector to the steering channel. The second axle will have the steering link mounted lower down on the servo horn than the first. This should allow for less proportional throw than the first axle and avoid any skid steering.

The servo on the second axle may touch the driveline between the second axle and t-case. If that's the case, I'll have to move the servo to the outside of the frame instead:

Overall shot:

Thought people might not know how to make up an Axial t-case so I posted up a couple of pics. It's pretty darn simple though.

First pic, is a stock transmission. You need to remove the motor plate, spur gear, spacers and any other washers and locknuts from that side.

You'll want to replace the stock screws with shorter ones. Before doing so, take the tranny apart completely and remove the top shaft (I used a non-slipper version). Chuck it up in your vice and cut off the threaded end and a bit of the shaft with a Dremel cutoff tool or hacksaw (best to measure before doing this to make sure you don't cut off too much!). Sand off any burrs, reassemble the tranny using shorter screws, and you have your t-case done.

 

[semijoe]

hey nice build so far

huge question, is this truck going to have some weight on it?

reason asking, the leafs will collaspe. its happened to me a couple time and i used smaller leafs. just my 2-cents

 

[ecoli]

^^^^^^^^^^^^^^^^^
Nice

Thanks

hey nice build so far

huge question, is this truck going to have some weight on it?

reason asking, the leafs will collaspe. its happened to me a couple time and i used smaller leafs. just my 2-cents

Likely it will have some weight to it, although I'm surprised at how light it is so far. Everything I've done so far is a testing phase of this build. I'll run it for the summer, see what needs to be modified and then rebuild it over the fall. The leaf packs are fairly stiff, but if they collapse, I'll switch to a shock and leaf set-up.

I'm not too worried about the suspension being like the 1:1 (which actually has independent suspension I found out!), but more worried about it working and not falling apart on the trail. Given that the suspension will be hidden by the wheels and tires, the fact that it may be "cheating" doesn't concern me

 

[ecoli]

I really like the look of this

Maybe do a similar version,would make one heck of a trail rig.This has me looking at my poor Hemtt that needs to be finished.I like the leaf set up,willhave to see how it works for you when you get to test it..

Thanks! Yeah, I like the look of that one as well. I've also seen a cargo version with a canvas wrapped frame which looked nice. It's nice a modular in any case, once the cab and motor areas are done, everything else can be changed at a whim.

I've been wondering what happened to your HEMTT. Hopefully you find the time to work on it and finish it one day. One of the HEMTT platforms was a close second for my choice in multi-axled rigs to build.

 

[ecoli]

Yea the Hemtt has been set aside and I keep looking at it saying I have to start on it again soon.The biggest thing holding me back is the cab,needs to be redone due to last owner who didn't really build to scale and the doors are a mess.

Well I hope you can get back to it again. These mult-axled builds are cool

Finished setting up the steering and hey, what do you know, it actually worked ! Quick video testing the steering and throttle:

http://www.youtube.com/watch?v=-gljEH5W51g

Still waiting on some parts (steel yokes) so I only have 1st and 2nd axle drive at the moment. At least I can move on to the bodywork finally!

 

[Slipstream73]

This is already blowing my mind, can't wait to see the body start to take shape. Great choice of vehicle, like the fact that you can changeup the look if you wanted to....How about a scud missle?lol Great job, I'll be watching this one.

 

[ecoli]

It's been a while since I updated this. Got the bulk of the styrene work done (go easy on me, my first time doing a scratch build with styrene!). I screwed up the driver's side cab and it sagged down on me. Its ok though, as I said before, this body was always meant to be a first go so I could learn from my mistakes. I'll strip it down in the fall and rebuild the whole thing over the winter.

Some pics:

A few questions for others that are much more experienced with this:

1. The main styrene platform sags at the edges from the weight. I'm thinking for the next body building that with 1/16" sheet aluminum. I think the weight will be a little more, but a lot more stiffness. Any thoughts on that?

2. As semijoe noted to me, the weight of the body is causing some issues with the leaf springs, they just can't hold up to it! I'm thinking of going with a leaf/shock set-up using the RC4WD 70mm shocks (http://store.rc4wd.com/The-Ultimate-Scale-Shocks-70mm-Black-_p_1366.html). Any feedback on these or any other suggestions?

3. As you can see from the door grooves, it looks like they were done by a blindfolded monkey on crack. To do them, I used a point tip on my soldering iron to rough them out (melted the plastic a bit) and then cleaned the grooves out with a screwdriver tip. Obviously not the way to do it, so looking for other suggestions?

4. Cutting out windows was a pain as well. Any tips on how to better do this?

For the most part, I'm happy with where it's at. I've learned a lot about building a multi-axled build, so doing the next body will be much easier, I hope!

 

[MegaToys]

Where did u get the aes from? A d roughly how much are they? Lol

 

[imthatguy]

It's really coming along nicely sir.

1. The main styrene platform sags at the edges from the weight. I'm thinking for the next body building that with 1/16" sheet aluminum. I think the weight will be a little more, but a lot more stiffness. Any thoughts on that?

Sandwich styrene slabs together after you've cut a pattern. Much more rigid.

2. As semijoe noted to me, the weight of the body is causing some issues with the leaf springs, they just can't hold up to it! I'm thinking of going with a leaf/shock set-up using the RC4WD 70mm shocks (http://store.rc4wd.com/The-Ultimate-Scale-Shocks-70mm-Black-_p_1366.html). Any feedback on these or any other suggestions?

How many leafs are you running? I've got four helpers on my Dodge now, and it's solid wood.

3. As you can see from the door grooves, it looks like they were done by a blindfolded monkey on crack. To do them, I used a point tip on my soldering iron to rough them out (melted the plastic a bit) and then cleaned the grooves out with a screwdriver tip. Obviously not the way to do it, so looking for other suggestions?

I score all my panels and snap them. I build up a bottom layer, then build a top layer that gets cut into panels, then glued on. No need to try to cut tiny lines that way.

4. Cutting out windows was a pain as well. Any tips on how to better do this?

Score and snap. Much easier. That, or do what you're doing, then use a nice H-Beam styrene to fab up window frame.

 

[pardonmyn00b]

Looks pretty darn good and you seem to have the hang of it.

1. The main styrene platform sags at the edges from the weight. I'm thinking for the next body building that with 1/16" sheet aluminum. I think the weight will be a little more, but a lot more stiffness. Any thoughts on that?

What thickness of styrene are you using? It helps to have many thicknesses in your arsenal. I like to make floors and bases out of thicker material than the sides. If all else fails, laminate the sheets together as previously mentioned.

3. As you can see from the door grooves, it looks like they were done by a blindfolded monkey on crack. To do them, I used a point tip on my soldering iron to rough them out (melted the plastic a bit) and then cleaned the grooves out with a screwdriver tip. Obviously not the way to do it, so looking for other suggestions?

I use a straight edge and score the grooves with a broken/worn #11 blade. Don't use it as a knife, but drag it sideways. Clamp the straight edge down if possible. On curves, like door lines, I cut a template out of styrene to use as a guide. And if you plan ahead you can do what imthatguy said. Sometimes I forget!

4. Cutting out windows was a pain as well. Any tips on how to better do this?

Try to cut everything out when it's two dimensional or in sheet form. Sometimes I drill holes in the corners of the opening and cut it with a knife. Other times I rough cut it with a dremel and use a sanding drum to smooth it out.

 

[RCFreak]

Looking good Chris

Might have to go for a road trip this weekend and check it out in person :)

 

[ecoli]

Where did u get the aes from? A d roughly how much are they? Lol

Not sure what you mean by aes? Do you mean the styrene? If so, you can get it from Johnston Industrial Supplies. A 4x8 sheet of 1/16" styrene is about $35.

How many leafs are you running? I've got four helpers on my Dodge now, and it's solid wood.

Thanks for all the tips. I'm running 4 leafs spread across two axles. Might try to boost up the number, but then you run into issues with your leaf pack becoming too thick.

What thickness of styrene are you using? It helps to have many thicknesses in your arsenal. I like to make floors and bases out of thicker material than the sides. If all else fails, laminate the sheets together as previously mentioned.

And thank-you for the tips! I used primarily 1/16" thickness all around. Might just try to use a laminated piece. It's quite a large piece for the base (about 30" x 9"), so it needs to come off a big sheet.

Looking good Chris

Might have to go for a road trip this weekend and check it out in person :)

Won't be around this weekend, but yeah, for sure I'll have to get her painted up and make a road trip with it. My hope is to come down to Lethbridge in August. Won't compete with it, but just tool around the site when I'm not watching the rest of you guys.

 

[RCFreak]

Won't be around this weekend, but yeah, for sure I'll have to get her painted up and make a road trip with it. My hope is to come down to Lethbridge in August. Won't compete with it, but just tool around the site when I'm not watching the rest of you guys.

Fine be that way haha

Cool on the August deal would be wicked if you were there to check it out its the funest rc event I have been to to date ..