Time for a rebuild

[jerry56]

Ok.... this was my first RC conversion I did it about 3 years ago... everything worked....but looking back it didn't look the greatest but I learned a lot...
I realize most of this will be old hat for most of you but hopefully it will help somebody starting out ... or doing a Tonka conversion


Knowing a little more now than I did then I decided to do a rebuild on it to see if I could come up with something better... so I started from scratch
new frame rails..they are 3/8 plywood edging AKA aluminum channel


they are roughly 13mmx13mm I cut the "legs" down to 8mm to give it a more frame rail look. I'm still using WPL axles and running gear so that makes my frame width about 56mm to keep the springs all lined up... the inside width is 52mm cause that's what the WPL transfer case is...


Now I have a 3D printer so I printed a servo mount and new spring hangers... no idea yet on how they will hold up but I want to at least try it...
The front of the leaf springs are screwed to the frame rail then the back just hooks over the rear hanger so it can float.


It's actually coming together better than I thought it would.

I got the front axle mounted, I'm not sure I'm going to use this driveshaft it works but looks kind of klunky



I'm using a different dump bed on the rebuild so I want to get it located on the frame before I start on the new dump cylinder. Plus I need to add a bracket for it to attach to



I want to keep it about 3/4 in off the wheels so I shortened the mounting tabs and made a spacer to get it up a little and not have the bed mounting bolt hit the rear wheels



There.. it sits level and is just about the right height... now I can get my distances for the dump cylinder

[jerry56]

So I got to work on the driveshafts and the dump drive....I found some WPL driveshafts that fit perfectly into a piece of 5/16 precision aluminum tubing.
[img]https://live.staticflickr.com/65535/51893463204_1732b44268_z.jpg[/img
First I cut a little off the female end and took that piece and moved it to the other end of the tube... then I trimmed the male end so I have about an 1/8 of an inch or so to drill into and not have it bottom out...

Then I JB welded both ends in and then drilled a hole for a 2mm bolt incase the JB weld didn't hold
[img]https://live.staticflickr.com/65535/51893777895_aa05d021d4_z.jpg]
Then I tackled the dump bed actuator This is the orginal one, it worked but I wanted something a little better looking. The aluminum butted up to the shoulder on the motor so it couldn't push back and the ziptie kept it from falling out. I used a masonry bit I cut down as a screw with set screws as "teeth" to ride up and down the bit...it worked pretty well but was really sloppy...

So I got a screw assembly from a Huina 580 excavator these had a lot less slop in them and were relatively cheap

Again I cut them down because the screw only needs to push the bed about an inch. I 3D printed a coupler to see how log it would last...I have a regular metal coupler 3mm x 6mm as a fall back when this one gives up.
This is what it looks like before I put it all together...it's a 33rpm gear motor with a 3D printed collar to hold it in the 25mm tube.





And mounted in place... I tried a couple printed mounts and the last one worked but looked odd to me so I went with the tube

I had to cut a groove in the tubing to clear the drive shaft....but you can barely see it.

So the whole thing can tip 8lbs to full height in about 8 seconds which looks "scale" to me
So I'm getting pretty close to wiring this all up hope to finish it in the next week or so....

[jerry56]

So I found that the tailgate wants to flop open as you drive, so I took an idea from another builder Scott "Smallhaul"that did this years ago . It's just a simple wire trigger that turns up as the bed comes down, completely mechanical so you don't have to use a radio channel. Pretty simple really as the bed comes down it pushes up in the other end of the wire...


You can see a small spring that pulls it down because if there is very much pressure on the latch from the tailgate because of a load of dirt it keeps the latch from dropping down so it needs a little help.


I wanted a little platform to mount my electronics on so I 3D printed a "floorboard" of sorts .... Wire management is not my strong suit as you can see.... I'll try and neaten this up a little but......



I'm using small junction blocks this time so I don't have as many JST connectors for things like lights and power to the ESCs and my "on" light... I put in a charging jack for the Nimh batteries...
So this week I want to get the lights wired up and the dump bed and body painted and make a tail panel. I think I might make a set of fuel tanks and put a set of mud flaps on it....

[frizzen]

That's a really sharp looking rebuild jerry!

I will need to steal some bed-lift ideas from that rig, it looks really stout.

[jerry56]

It is kind of bulky but that's due to the aluminum tube.But with that said it is stout and will push the bed up with 8lbs in it. I'm sure it can be mounted in a much "sleeker" way I just haven't figured it out yet. I made a couple different mounts but didn't like any of them I may re-visit them at some point....

[trilliwilli]

I got the front axle mounted, I'm not sure I'm going to use this driveshaft it works but looks kind of klunky

The steering rod is the wrong way around here, it should be on the backside. Now the outer wheel (bottom one on this picture) makes the sharpest turn and that should be the inner one.

WPL does it wrong on all their chassis, so does Tamiya by the way.

Look for the Ackermann principle, it explains how a steering axle makes the right angle for proper steering. Believe me, it will make a whole lot of difference once mounted properly.

[jerry56]

Yeah Trilliwilli that would give better steering but there isn't enough room behind the axle to do that.
The driveshaft, spring hangers and motor all get in the way...

[frizzen]

I was thinking more like some C-channel with setscrews for the motor mount instead of the really big tube.

Most rock-crawlers do the Ackerman wrong, because it's a lot easier to make it all fit. Highsteer rear draglink sometimes starts breaking knuckles, so it usually keeps stacking upgrades

[trilliwilli]

Make a new steering rod with a recess that goes under the driveshaft, the motor is not a problem then, and the ball ends can stay at the same hight.

Something like this:

[jerry56]

Frizzen.. I had a piece of square tubing before that was a lot smaller I may go back to it idk.

Trilliwilli. I'll have to take another look and see if I can make that work...

[jerry56]

I guess it's time to wrap this one up....I kind of glossed over some of the basic stuff... but this truck is on WPL axles, and transfer case the motor is a economy spur gear from Servo city 170 rpm and the gear box is 57:1 ...but I replaced the motor with a traxxas 28 turn for a little extra speed. The dump motor is a 33rpm mini econ gear motor...the bed lifts in about 10 or so seconds and dumps 8lbs. The tires and wheels are also WPL.
I wanted a red dump truck so I got it painted and added a few small details like saddle tanks, a tail panel with tail lights, back-up lights and a tow hitch. The running boards are WPL I just need to make some of my own, and the mud flaps are just inner tube. I want to add some mirrors once I find some the right size... working on that as we speak.
I just want enough detail to make it fun, I plan on getting my small "construction company" out in the dirt just need an excavator and a bigger loader...anyway here it is in all it's redness..

[Tgrzes]

That came out really nice!

[frizzen]

I really love how that came out! It's a great mix of scale realism, and pressed steel fun

Although, I still think it could use some tailgate chains
https://m.youtube.com/watch?v=ZaHdYDth-5E

[pufferfish]

Great job.
Looks nearly too bad to play in the dirt with.

[jerry56]

Thanks everyone....
It's still clearly a Tonka but just enough detail to make it fun.... but yes Pufferfish it's going to be out in the dirt...lol.. it is a toy...
I still want to put mirrors on it and I haven't given up on the tail gate chains.

[trilliwilli]

That turned out nice! Is the bed original to the cab, most of these Tonka’s I can find have the open bed like the one of your first rebuild?

[jerry56]

No this is a different dump bed... Tonka used both beds most of their dump trucks came with either or....they were interchangeable...
I got a deal on 3 dump beds...if your looking for them you can sometimes find a deal here on a "project" or parts truck, basically it's a little to rough for the collector. But they are fine for what we do with them.
https://www.facebook.com/groups/239101843186907/

[ddmckee54]

jerry56:

That's quite the transformation, it looks good in the dirt.

I got that same wheel/tire/axle combination to try on one of my Bruder conversions. But they were too small and didn't look right on that bigger truck. On your slightly smaller truck they look like they were designed for it.

It looks like you did a fair amount of "bodywork" to get the cab/fenders to their final condition.

Don

[jerry56]

Thanks ddmckee,
Scale wise the WPL axles are a little small for the Bruder's, if you can get past that and use 5mm to 12mm hex adapters and then use bigger wheels and tires they might work....But your right they are a perfect fit for this size Tonka/Nylint/Buddy L even the Ertl Big Farm
The body of the cab was straight just had a lot of play wear, I just stripped it and repainted...The bed on the other hand was pretty rusty and was played with pretty hard through the years. It was considered a "custom project" piece meaning it had lost most of it's collector value...but the outside was straight and ...it's a toy after all that I'm taking to the dirt...

[skeeter]

Originally Posted by jerry56

frame rails..they are 3/8 plywood edging AKA aluminum channel


they are roughly 13mmx13mm I cut the "legs" down to 8mm to give it a more frame rail look.]

Now I know what to look for! I have seen this used as frame rails for custom built trucks before. When I went to Metal Supermarket to try & source some, they had no idea where they could even source it from. I'll have to try looking at Home Dumpster &/or Lowes the next time I go to one of them. I'd LOVE to score about 16 foot of that stuff!