A newb builds a FOFFer - aka WTFOFF

[MiteyF]

I only got into the hobby about a year ago, but have kind of gone off the deep end since then. I'm a builder at heart, and just love to make things. These little guys are also a great way to spend time in the winter months here in Michigan when it's too cold to be riding motorcycles and tinkering in the garage.

A few months ago I finished my first custom build, a little sand rail to tool around in the back yard. It turned out even better than I had expected, and since moving late last year I found there's a construction site (more apartments I think) just down the road from my house. I took the rail out there a week or 2 ago and it was a hoot... but I thought that a FOFF build would be just the ticket to rip up and down the dirt/sand piles.

So here we are.

Wheels, tires, axles and motor/esc are all either on hand or on order (although I'm having a problem with my ebay-ordered axles, over a week and they still haven't shipped...). Since I've got most of my parts figured out, I'm hoping this will be a fairly quick build. Hell, it may even be done before all the snow melts! This won't see any comps or anything, just a general basher. I do however have a tendency to take what is supposed to be a "basher" and start adding scale stuff... sometimes to no end.

Parts list so far
-All metal AR60 axles
-RC4WD FOFF tires (although they look a bit small, so we'll see)
-Chinese (gasp!) aluminum beadlocks
-Trackstar 21.5t brushless combo
-2200mah 3s lipo
-AX10/SCX10 trans
-Traxxas 100mm big bore aluminum shocks
-3D printed engine and other doo-dads

I have never done a build thread before, as I have a tendency to start a project and work tirelessly until it's done... forgetting to take pictures or make posts during the process. I hope that's not the case here. I just picked up a 3D printer though, and have been putting it through its paces, so hopefully having a computer in the shop full-time will be enough encouragement to keep the thread something resembling up to date.

Enough chat. A few pictures perhaps?

[MiteyF]

So I'm not really a think-measure-draw-rethink-erase-remeasure-draw kind of builder. Not in 1:1 stuff, and certainly not in the world of tiny trucks. I'm prone to get an idea in my head, and start making shit. Then if it doesn't work, I either *make* it work, or scrap it and start over.

That's important to remember here.

Also important to note is the fact that me being more of a builder than a driver, I'm not planning for perfection. So long as this thing is fun to drive when it's all finished, without any major flaws, I'll be stoked. With that said however, any and all suggestions are very much appreciated! If my link geometry looks screwy, please say something! Shock angle/travel looks wrong? Tell me! I'm not a very patient person, and I'm stubborn as all hell, but that said, I still appreciate constructive criticism.

Alright. Just for shits and giggles, the sand rail/rock buggy wanna-be (AKA, the GoPro Sled), my first custom build. Mostly Rustler running gear. A little heavy, but surprisingly quick (to me at least) on a 2s with a 19t motor. I'm still fine tuning the suspension. This rig got me hooked on the speed that the crawlers just can't quite do for me.

[MiteyF]

OK, on to the project. I started with a *very* rough sketch, with a general outline of my desired wheelbase and the outer-most limits of where I wanted my body/chassis to be.



Start with some metal. I'm using 3/16" solid rod, because it's easy to bend, and easy to TIG weld. Not terribly light, but super strong. As always, the hard part is making each side identical without taking the time to form a jig (did I mention I'm terribly impatient too?). As you can see, I'm already straying from my initial drawing.



These RC4WD tires sure are smaller than I'd imagined (no one's fault but my own of course), but the more I look at pictures of 1:1 rigs, the more scale they look. I'll build with these and change things later if I see the need.

EDIT: don't mind the old Chevy, that's another (very slow) build/thermoforming project

[MiteyF]

With a good portion of each side welded up and as close to identical as is reasonable to ask of a hack like myself, I guesstimated on a chassis width. I'm keeping the whole truck mostly square (width equal from front to back), both for ease of building/measurement, as well as a scale-ish look. I may add some lateral dimension with body work (fenders etc) but that has yet to be seen.

Without my axles and wheels on hand (told ya I was impatient) I can't be totally sure this is exactly what I need, but I'm pretty confident it will clear the tires with ease, and should put my shocks in just about the right place side-to-side to give me plenty of mounting options come the time.

I probably won't get much (if any) more metal work done until my wheels and axles arrive. With only these 2 braces tacked in place, if I do find I need to alter the chassis width, it's just a matter of removing or adding a small bit to the 2 existing cross braces, and keeping things square.



Looking better than my drawing already (which isn't hard to do, I'm far from an artist). This is also close to the ride height I'm going for. I'm not looking for crazy ground clearance, and this puts me at about 2" from the chassis to the dirt. I'm thinking curved bottom links should give me all the clearance I'm looking for.

[MiteyF]

Isn't waiting on parts a PITA?

I recently acquired a 3D printer (after many months of trying to convince myself I didn't need one) and must say, this is probably one of the best toy truck investments I have ever made, aside from a dremel and a lot of beer

It's like having an extra set of hands. I can be welding/cutting styrene/daydreaming/drinking, and have this thing cranking out parts. It's far from plug and play, and there is more than enough fiddling to be done, but it's really awesome, and much cheaper than most would imagine.

I've really got a weird thing about scale doo-dads, and this truck was always destined to have some, whether or not I want to admit my urge to add "scale" to a "basher".

First on the list is a V8 receiver box (not my design) intended for a Wraith. Whether or not it actually houses my receiver, we have yet to see. If nothing else, it will look good on the shelf of random RC-ness when I scrap the idea.

About 3 or 4 hours of printing for the block.



Valve covers are printing as I type, then next up is the intake manifold (been having troubles with that part for some reason).



This one is too small (printed at 1/7 the intended size) and was destined for my sand rail. I decided to go with a single seat in that rig, so this one sits on the aforementioned shelf. But I think a bucket seat or 2 in this rig would look quite the part.

[MiteyF]

Motor/ESC got here today along with a few new batteries. Axles should be here tomorrow. It starts to look real small with just a few electronic bits inside! The more I look, the less I think I'll have any room whatsoever for scale goodies

[MiteyF]

A short motorcycle ride to the LHS yesterday (spring is finally coming, hoorah!) got me some more bits. A new servo and receiver, battery/ESC plugs, Traxxas link ends and some more aluminum for the links, as well as a cheap set of 2.2 wheels to use for mockup until my beadlocks are off the slow boat from China (literally I think). For better or worse, the LHS that opened about 2 or 3 years ago is awesome, with a huge selection of stuff and super helpful employees. Every time I go, I end up spending WAY more $ than I planned. I'm pretty sure their eyes turn green when they see me pull up.

We now have a complete radio system.



Also, my axles finally arrived, the next crucial link in the build.



And the LHS didn't have the shocks I wanted, so I'm stealing the ones off my buggy for the time being. Either I'll buy the buggy some freshies, or return these and buy others for the FoFFer. They're big bore Traxxas shocks, with uber stiff springs, coming in right about 100mm. They're cheap, work great, and don't leak a drop!



Let the build commence.

[MiteyF]

First thing I noticed after a rough layout, with the pumpkins on these AR axles, I'm going to need bigger tires (I've never used AR axles before). I just don't have the clearance I want. However, that can be sorted later.



Also, I decided to raise the chassis up a bit, although I'm still playing with final ride height.



The first thing to be sorted was the chassis width. It was about the worst possible width, as it made it impossible to mount the shocks. I had 2 choices. Narrower chassis with shocks on the outside, or wider chassis with shocks on the inside. I went wider. Any narrower and it would have been comically small.

Added about 1-1/4" to the width to get 5-1/4" on the inside. That's about as narrow as I can go and still have the shocks fit inside the body.

Next thing was positioning the axles, which meant a skid and links. I learned from my rail build that even thin sheet metal adds huge amounts of weight, so I went as small and light as I could. I eyeballed and measured my Bronco's trans, and I should have just enough room to mount it without having to space it up off the skid.

You'll have to excuse the poor welds (well, you don't really HAVE to) all I had on hand with the proper ID was some SS tube, no mild steel hanging around. And before you ask, yes, you can weld SS to mild steel, and it's plenty strong, just a bit of a PITA (especially with thin stuff) for a hack like me. This week I'll be getting some more steel. I'm almost out of rod, and completely out of tube at this point.

[MiteyF]

That was yesterday's work, here's today's.

After getting the skid nice and straight, I threw a tack weld in each corner. This way, when I put on lower links that are exactly the same length, if I notice something's off, I know exactly where the problem lies, and don't have to cut the whole truck apart to make it right. This isn't something you want crooked obviously, or nothing else you do from here on out will be right.

Next was obviously lower links to get the wheelbase spot on. One big thing for me after driving my buggy, is a low COG. I've decided to sacrifice some ground clearance to get my COG as low as possible, with as much weight up front as I can get. Because of that, I decided that bent lower links were absolutely necessary.

I use 2 tubes when I build my links. The smaller has an ID perfect for a 3mm thread, and the outer helps beef it up the tiniest bit. There is only a small fraction of a mm difference between the OD of the smaller stuff and the ID of the larger.



This puts me at about 12 1/2" wheelbase. Perfect.

On the rest of these pics, ignore any and all shock locations, I just used them to eyeball my ride height without supports. None of these are where the shocks are going. And obviously, without upper links, the pinion angles are not what they should be. Disregard

This was moving a lot faster than I'd planned over the last couple days, and before I could do much else, I needed a trans to eyeball driveshaft placement etc before I could get any upper links or shock mounts done.

My impatience (remember me mentioning that?) got the better of me, and my poor poor Bronco was kind enough to let me borrow a trans for fitment. Don't fret, there's another on the way, with an aluminum housing sooner than later.





I needed to bolt up the new motor to make sure it would clear whatever obstacles may try to foil my plan. Not what I had in mind, but it will work. I think I can use the space I still have wisely. I've got a strange fetish for tight tolerances and well fitting parts, whether or not that's what's happening here





I'd say my eye-crometer is well calibrated today.





Again, disregard shock location, but this is about the ride height I'm going for at this point. Shock mounting and upper links are next, now that I know where my driveshafts sit and approximately where I want my ride height.

[MiteyF]

Seems I've got a captivated audience of one... I suppose we'll call this my private build log Thus, I'll keep it short.

First up were rear shock mounts. This gave me my ride height, so I could get my rear upper links. Since I've got the same length links front and rear, getting the rear more or less completely situated makes getting the front tidied up much easier. A few tack welds later and viola.

I figured to forget "lightweight" as that ship had sailed. The name of the game now is "beefy".

Thus, I decided that the best next move would be a few side panels, which serve as both upper link mounting points, and some protection for the electric bits. She'll be plenty rock-proof when it's all said and done.

A few upper links in the rear and the ass end is sorted.

Again, ignore the front shocks for now.









I've got a love/hate relationship with tight fits. I love it when things fit nicely. I hate taking stuff apart to get to other stuff.







Also, wheels! Not the easiest to mount up, but they're nice and light, and look the part. Good price too.







And just as I was hoping, lots of offset. This narrowed my track width about 1/4" on each side.

[MiteyF]

Sitting on her own 4 wheels! Got the upper links in the front mounted as well as the shocks. I had to alter the front end for clearance at full bump too (figured that since the beginning). I also got my Wraith trans. Some hardware and steel driveshafts are on the way, I'll head to the LHS this weekend and pick up a pinion, and That should be all the bits I need to finish her.

Thus far, this has been a super fast build!

[MiteyF]

A little storm ran through yesterday, and today was a snow day for me. The old lady couldn't even get out of the driveway without help. Thus, I got a *bunch* of work done on the FoFFer.

My McMaster order came in, so I tacked in some threaded spacers and fully welded the chassis.



And how about a terrible picture of terrible paint?



Disassembled my axles, and reassembled with good grease (they were basically dry), better quality hardware (I love McMaster) and Loctite.






A few nuts and bolts (some temporary) and it's starting to look like something!

[rustneversleeps]

great stuff well done..i don't see it mention but did you think about turning your tranny the other way so that the shafts line up to the rear ends....

[MiteyF]

Originally Posted by rustneversleeps

great stuff well done..i don't see it mention but did you think about turning your tranny the other way so that the shafts line up to the rear ends....

Thanks. With the trans the other direction, the shafts interfere with my links. This should work fine, although if I notice otherwise, all it takes is moving some wires and drilling a few new holes. The beauty of building things is that you always know how to fix them

So, today had its highs and lows. First, I realized that the motor/ESC combo I bought won't take a 3S... I don't know if I misread or mis-ordered, but that's what it is.

I'm too tired to type a whole lot, so here's some pictures and I'll try to get a bit more description down tomorrow, if the work bench doesn't suck me in. Besides, isn't that why people look at build threads?

Note that some bits are temporary... etc

[MiteyF]

Today's work. New springs front and rear, although I think they're still too stiff. The LHS was out of some spring rates.

Like I said, I was wanting to run 3S, but my dumb-assery temporarily prevented that. I want to get it out and run it ASAP, so I found a temporary solution while I was at the shop... a 35 tooth pinion Until I get a new motor and what not, we'll see if we can't screw something up! I even had to extend the slots on the motor mount to get it to fit.

She got some color today too. I've got a weird thing for lime green, and this Tamiya Candy Lime Green looks the tits in good light. Still finishing the hood/battery mount (although it's almost done since these pictures were taken). When I switch to 3S I'll also have to modify/rebuild the battery box/hood, but for now, what I've got in the works should get me out and playing in the dirt.

Sorry for the cell phone pictures, once she's tidied up I'll grab the real camera again.

[MiteyF]

While I can't honestly call this rig "complete", I fully plan on getting in a quick test-n-tune tomorrow. We're supposed to get about 2 inches of snow tomorrow, so I'll try and do some donuts if nothing else (although I still have to waterproof the electronics... shhh...). I've got a GoPro mount printing at the moment, so I'll get that stuck on and as soon as I get her out I'll try and get a short video posted. I've still got some additions/changes coming her way, but I'm impatient and can't resist a quick run.

Oh, and ignore the crooked steering link Gotta get my toe (roughly) set before I roll it outside tomorrow, as well as the clutch, and see what the stock settings are on the ESC.

I had a few pictures for you (aka, just me), but photobucket is refusing to upload. I guess it will wait.

[MiteyF]

It seems photobucket is behaving a little better today.

I took her out about a week ago to give a little test and tune. First impressions? It was ungodly slow. No wheel speed whatsoever. Luckily, I've got another project that I think the 21.5 turn motor/2S ESC will work perfectly for. So first thing's first, I ordered up a Castle Sidewinder 3. I opted for the 5700k motor (gasp!). I figure this will give me parts-breaking speed on 3S and... well, something just less than that on 2S.

Unfortunately my 3S battery didn't fit under the hood nicely like my 2S, so for a little testing I lazily slapped it in a very terrible, temporary spot. A (very) quick spin/drift around the basement, and I encountered a wall. Less than 30 seconds run time and I already broke it

If this keeps happening I'll have to deal with it more permanently (stronger, or at least straight links). For now, I just bent up another link.



Took her out again yesterday (about 2 or 3" of snow on the ground) and I have come to 2 conclusions. 1) *plenty* of wheel speed, and 2) not enough ground clearance, just as I had assumed. The pumpkins worked as a wonderful snow plow though I also think I still have to soften up the shocks substantially, or replace them altogether.

I've got some regular 2.2 crawler tires on their way from RC4WD, just to see. I threw on the 1.9's I run on my Bronco just to see what it looked like, and I must say, she looks mean!

Either way, neither of my short videos are anything worth uploading, but here are a few pictures as she sits at the moment. Sorry for the poor lighting, my basement doesn't offer many options, and I was too lazy to get out the flash for the Canon.

[cabron]

a couple of things to think about

jato rod ends are normally for 4mm threads but you can use 8-32 or even 10-32 or 10-24
using 3/16 rod, cut threads and run a tap into the rodends and get stronger links. I use 10-32
but there is no real reason you cannot use 10-24.

the other thing is a straight forward mod for the traxxas shocks, grind off the top ear so the cap is flat across the top,
drill an appropriate hole and use another rod end running the screw from inside the cap.
this way you will have a ball up there for a bit better shock articulation.

nice to see someone build a rig from axles and a tranny. anyone can buy parts and assemble but making
the car is a more personal thing.

enjoy

p.s. consider a 3s lipo for a bit more wheel speed. hahahaha

[MiteyF]

Cabron - thanks! I'm always surprised at how many folks are willing to shell out hundreds of dollars on fancy parts, and still end up with something that looks like every other SCX, Clod, AX etc. Building is half (or more) of the fun for me. And check the last post, she's on 3S now, and plenty fast.

If these links don't work out, next step will be to try straight links of the same style, as I've had super good luck with them on my SCX and other rigs. The bend is most certainly the weak point.

Also, if I decide to change shocks, I'll likely just pick up a different pair (my LHS has a set on order I'd like to try) as these Traxxas shocks technically belong on my sand rail.

It's supposed to rain a bunch the next few days here, but if it dries out a little I'm going to try and at least get in a quick blast around the yard. I've figured out my battery mounting, and will toss up some pictures of the "finished" rig soon.