1985 1/9 Suburban scratch build

[JoeThePro]

(Copied from original posting at Scale4x4RC forum)

Dont let my username fool you, I am a styrene virgin. This will be my first build and its going to take some time, and I know there will be much cursing and reworking along the way.

I decided on a ~1985 suburban 4x4, always loved the way they looked and sat. I also had no idea at the time I started this that RC4WD has the same gen blazer bodies that people hack up to make easy suburbans. Kinda took the wind out of my sails when I discovered that this is in no way a unique build, but screw it I'm gonna make it work.





Im going to use TRex 60 axles from rcw4d, and with their 7.3" hex to hex width, it puts the scale at just about 1/9. So I will make the chassis and body accordingly. Body is going to be 24.3" long, so it will be nice and BIG! :excited: Im going to use leaf springs, havent worked those out yet though.



For the rails, I initially ordered 2 raw steel scx10 sets from Hot Racing. They arent nearly long enough, so I was going to cut one of the sets at the low point and braze in material from the second set to make it the proper length. But... the vendor has issues getting the product and had to refund my money.

Here's the bench setup so far. No real progress on anything, still waiting for the axles to arrive this week, and I want to make sure I have the printouts properly sized for comparison.

[JoeThePro]

So these are pretty much the final dimensions of the body. The height isnt listed but it will be 6.4". The three numbers at the bottom right are wheelbase and F/R track width.

[JoeThePro]

Finally got the axles. I threw on some 1.9s that I had from my Tamiya CC01 FJ40 to see how it would look. I think Ill end up using 1.55 Baja MTZs. They look pretty sick and are very close to what I wanted for a stock tire size.

For the chassis I'll either make my own from square tube (it is DAMN hard to find 7/16" or 1/2" square tube in 18ga, 16ga will have to suffice) or use the GCM CMAX chassis like pardonmyn00b is doing. Its nearly the perfect length, with enough room for the long burb wheelbase.



I finally started cutting into some styrene. My 12x12 sheets should arrive tomorrow, so for now I am working on the tailgate with my 6x12 sheets. It took WAY longer than it should have to measure, cut, and glue two pieces together at an angle, but I'm a quick learner (that engineering degree must be good for something), so hopefully Ill start to speed up here and learn some tricks.



It seemed like that joint might be a weak spot, so I kind of braced it by gluing 2 small strips together at the joint in a few places. There's probably a better way to do this, but it seems to work pretty well.

[JoeThePro]

Got the body traced out and can now make panel templates to cut around.
The front quarter panels are roughly cut out. I want to try to make some of
the inner frame as well, like the engine bay and door frames so that the doors and hood/tailgate can open and rest shut properly. That's a little ways down the road though.

[JoeThePro]

I was getting frustrated trying to plan how I would do the outer panels and get the subtle curves worked out all over the place, so I switched gears and started on the interior. I figured this would give me a good base to work off of, and going inside out instead of outside in seems like a much better idea.

So I made the bottom runners that go under the side doors, and I put the floorboard and front seat riser together. Next Ill do the bed/back area and start on the lower walls. From there I guess I can start building out a bit and get the firewall and hood vents in place. This is so much fun, but damn its time consuming and frustrating! Messed up many times, spilled glue, etc... A great learning experience, for sure, I can tell I'm getting much better at it after this past week of working on it for hours almost every night.

Side view of the bottom runner


The front half of the floor, the pedal area, and seat riser. The above runner will be glued to the bottom sides of this piece.


I also got the hood cut out. Its going to be tough to cut the downward curve (towards the grille) right on this... any tips?


I setup my dremel in my vice and screwed a piece of wood to the front of my bench for a makeshift router/shaper. Works really well for material removal and rough shaping. (Thats paper in the bin, btw, not styrene!)

[JoeThePro]

Got the bed area started.

[hotwheels000]

Nice start, styrene is fun.

I might suggest that you go back to the body first. Reason being is once it is built and ride height on the chassis is determined you most likely will find you are going to be reworking the interior to clear all the chassis components.

[JoeThePro]

Originally Posted by hotwheels000

Nice start, styrene is fun.

I might suggest that you go back to the body first. Reason being is once it is built and ride height on the chassis is determined you most likely will find you are going to be reworking the interior to clear all the chassis components.

Thanks, it is definitely fun once you get used to it. I do have some 1/2" steel tube and I did a test bend on with some heat and I think it will work well for making the rails. Just gotta find someone to split it for me...!

Got the wheel wells and spare tire holder done, but I was looking at the wrong lines on the very busy drawing I have, and I made the wheel wells too short! :banghead:



So I had to chop them up and extend them, and at that point I was frustrated and just didnt want to deal with the spare tire well. We'll see if it makes the final cut, or if a facade gets slapped on.

I roughly cut out the firewall and side panels, so the shell is finally starting to take some shape!





As a side note, Ive found that I like using plastruct bondene over plastic weld, it just sets so much faster and is just as strong, if not more so. If the material is too thin, like 0.02, it can eat away at it a bit more, so you need to be careful with it. Its definitely a hotter solvent.

[hotwheels000]

Take a look at the weld-on 3 product line. My buddy who owns a plastics manufacturing shop turned me on to it. Works very well and much more cost effective. MEK and acytone also work and are available at any hardware store.

Although weld-on 3 is my go to solvent weld for plastics.

https://www.amazon.com/Acrylic-Plast.../dp/B0149IG548

[JoeThePro]

Originally Posted by hotwheels000

Take a look at the weld-on 3 product line. My buddy who owns a plastics manufacturing shop turned me on to it. Works very well and much more cost effective. MEK and acytone also work and are available at any hardware store.

Although weld-on 3 is my go to solvent weld for plastics.

https://www.amazon.com/Acrylic-Plast.../dp/B0149IG548

Thanks, I'll check it out. My LHS carries the Plastruct products, so I'm probably going to stick with that since it has worked so well for me so far.

I've decided to change gears to clear my head a bit and start work on the chassis. I mocked up the rail shape that I will eventually bend into my 1/2" steel tube and then rip in half with a dremel. I'd like some input as to the shape, does it seem like it will work OK? I looked at as many reference images as I could to get an idea of where to go with it, I think maybe the area over the front axle needs a bit more curve/space on top? It also may be a bit long, probably need to trim like 0.5" off both ends.

[JoeThePro]

I think I really want to try IFS on this build now. I wanted to initially, but I didnt think Id be able to make it work and a solid front seemed much moe attainable. But Ive seen some other builds that have done it and since the 1:1s have it, I think Im going to go for it.

Any tips on parts I could use would be appreciated.

I know Ill need at least:
- bulkhead/diff
- hubs
- knuckles
- driveshafts/dogbones
- top/bottom arms (I could potentially make these)
- chassis mounts (I could potentially make these)

Ive seen others use yeti and 1/16 revo parts, among others. It looks like HPI RS4 parts could work as well. Not sure if that's a direction I could/should head. I think the hardest part will be controlling the width to get the exact track I need up front.

[Itali83]

Do what you want but the 1:1's do NOT have IFS. They didn't go IFS until 1992 just sayin'

I am enjoying your build by the way though. Keep up the good work.
Ben

[JoeThePro]

Originally Posted by Itali83

Do what you want but the 1:1's do NOT have IFS. They didn't go IFS until 1992 just sayin'

I am enjoying your build by the way though. Keep up the good work.
Ben

I just realized it was the 4x2s that had IFS. The 4x4s had a solid front. Thank you for the heads up!! I had no idea. I always thought the solid fronts I saw were axle swaps. Im such a noob.

[JoeThePro]

Well, I tried steel square tube and aluminum channel. It's just not in the stars. If I had 18ga steel I could probably manage all the bends and splitting, but 16ga is just too much. The aluminum just wasn't the right size and the Dremel wheel was bending in my jig a bit resulting in curved cuts. General PITA.

Seems like my only other options are to get some thin solid rectangle steel bar about 0.5" wide and bend that to shape, or just get something like a CMAX rail set. Very frustrating. Only other thing I could think of is to get a second set of hot racing scx10 rails and slice them up into the first set I got to get the length I need.

Sent from my Nexus 5X using Tapatalk

[JoeThePro]

So, I finally had success with the 0.5" flat steel bar. Got one rail bent up, I may just leave the back flat, we'll see. Just need to trim the ends. The other one is going well, should end up with a nice set. Finally!

[JoeThePro]

Rails are done. Top is SCX10 chassis, bottom is my custom chassis.

[JoeThePro]

For some reason, Santa showed up this morning dressed as the mailman.

[JoeThePro]

I went to the hardware store to get a bunch of stuff to get the axle/chassis leaf mounts started. I found these great chain links that I think could work as shackles, but Im realizing they may be too short, so Ill probably just make my own. I cut up some aluminum to use as hangers, and I'll just drill some holes in the chassis for all these. I also got some lawnmower pull start return spring, and I'm working on making leafs out of it. I think I can make it work.

Does it look like Im headed in the right direction as far as placement? The leaf is centered over where the axle will be, but does it matter if the rear mount is higher than the front mount?

[JoeThePro]

I found some thin patterned aluminum sheeting that I had and I think this will work better, maybe?? Does it look like the appropriate length for a shackle now?

[hotwheels000]

Looks good currently, I would drill a few optional holes as once the body is placed your leafs are bound to compress. You may need to adjust the placement of the rear shackle to compensate for the sag. Much easier to drill the holes while the chassis can be placed back to back and drilled at the same time to ensure consistent placement.