Tonka Conversion

rsd53 · #1 10-03-2013, 07:41 AM

I've had an affection for 50's a& 60's Tonka fire trucks since I discovered them, as a child. Although I never got one back then, I have finally filled that 55 year old void, with some eBay purchases.

Since discovering the world of RC trucking, I've had a desire to do a conversion of an aerial ladder truck. Everything I need to do seems pretty straightforward. The thing I'm struggling with are the axles.

These trucks are 1:16 scale and I need to find something with the proper width for front and rear. The only other obstacle is mounting the hard rubber tires to them.

If someone could get me started in the right direction, I would really appreciate it.

I would be using a truck similar to this one. the goal is not only to be able to drive it, but be able to raise and lower the ladder, extend, retract, and rotate it. for finishing touches, I would add lights, sound, and a rotating beacon

RCP57 · #2 10-03-2013, 09:18 AM

That will be an awesome project! What width are you looking for on the axles? The front would be quite simple to make but the rear may be more of a challenge depending on width.

Keep us posted!
Reg

Finster · #3 10-03-2013, 09:27 AM

Cool project although you might upset a few Tonka collectors, but who cares about them. Anyway, Scott (SmallHaul) did a conversion on a Tonka dump truck which might help give you some ideas or at least see how he did things.
http://www.rctruckandconstruction.co...ght=tonka+dump

I think there have been a couple other Tonka conversions on the forum too, just search and I'm sure you'll find them. Hope this helps...

rsd53 · #4 10-03-2013, 10:25 AM

Quote:

Originally Posted by Finster

Cool project although you might upset a few Tonka collectors, but who cares about them

Now wait a minute, I'm one of "those people", but I will remain anonymous!

Quote:

Originally Posted by Finster

Anyway, Scott (SmallHaul) did a conversion on a Tonka dump truck which might help give you some ideas or at least see how he did things.

I've seen many of them on youtube, so maybe my first stop should be with Scott. Thanks for suggesting him.

RCP57 · #5 10-03-2013, 10:31 AM

Since the rear width is so narrow, maybe you could use 360 rotation servos for a drive setup? That would eliminate the need for a driveline completely and leave the truck largely stock in appearance. Just a thought.

SmallHaul · #6 10-03-2013, 11:17 AM

That ladder truck would be cool converted to rc.

i use the axles from a mini giant rc monster truck but, they quit making them many years ago and rarely come up for sale on ebay.

But, if you only need rear wheel drive you might check out the tiny metal axle that rc4wd sells. It is a 1/18 t-rex micro axle. The axle is very small but it is all metal so, you could extend it to the width you need..

http://store.rc4wd.com/118-T-Rex-Mic...xle_p_438.html

Good luck and have fun.

rsd53 · #7 10-03-2013, 10:20 AM

Quote:

Originally Posted by RCP57

What width are you looking for on the axles?Reg

Thanks for your interest.

I don't see mounting axles as a problem, but maintaining the stock width is. The truck is made of pressed steel and its thickness is .035". Outside of the frame at the rear measures 3.250". Outside of the front is 3.625". The rear is narrower to accommodate dual wheels.

Both of those widths would be my starting point, but I don't know what else would affect the actual final width of either. I've seen straight axles for the front, but get dimensions of spindles to determine final width.

Any help with this would be appreciated.

jd*rccustoms · #8 10-03-2013, 03:19 PM

Can you take a dremel tool and make a slot inside of the wheel for the pin on the axle. And then when you put the axle nut on the wheel should actually drive.

rsd53 · #9 10-03-2013, 05:20 PM

Quote:

Originally Posted by jd*rccustoms

Can you take a dremel tool and make a slot inside of the wheel for the pin on the axle. And then when you put the axle nut on the wheel should actually drive.

I don't have any problem doing that, I'm not sure if the axle shaft in the differential, is large enough to put the pin in.

RCP57 · #10 10-03-2013, 06:07 PM

If you look at the pictures closely it appears that the axles are already drilled for cross pins.

rsd53 · #11 10-03-2013, 06:53 PM

Quote:

Originally Posted by RCP57

If you look at the pictures closely it appears that the axles are already drilled for cross pins.

You know, I believe you're correct! Thanks for pointing that out to me.

RCP57 · #12 10-03-2013, 07:14 PM

No problem!

rsd53 · #13 10-05-2013, 09:06 AM

Ok boys. settle down, or take it outside the forum!

I've been searching ebay for construction materials, and some of the basic parts I'll need for the build. I found some Tamiya TAM9808205 leaf springs, that look similar to those Scott used. I still need to find out what the thread size is on the 1/18 T-Rex Micro Rear Straight Axle is at RD4WD. Next I'll have to find a front axle.

Rvjimd · #14 10-05-2013, 09:56 AM

Rsd,

Slow down on the build, would you? Where's the fire?

Jim

rsd53 · #15 10-05-2013, 10:06 AM

Quote:

Originally Posted by Rvjimd

Slow down on the build, would you? Where's the fire?

Jim,

That reminds me, I need to get a reducer to go with the motor and transmission, I have yet to address!

Rob

Finster · #16 10-05-2013, 10:47 AM

Well it IS a fire truck...

rsd53 · #17 10-08-2013, 06:17 PM

Quote:

Originally Posted by Finster

Well it IS a fire truck...

That it is, and still completely static!

Over the weekend, I ordered some aluminum channel, and material for the cross members.

I've been working on preliminary CAD drawings for the mounting of servos, motors, and lights for the trailer. That will keep me busy for quite a while, based on the number devices I'm looking at.

At the same time, I would like to get the truck conversion completed. My plan is to use as many used parts as I can. Right now, I'd to locate a motor, transmission, and reducer for the truck. If anyone has these, and is willing to part with them, please PM me.

Rob