Ultimate JP toy conversion

[Nikko85 4209]

Ask anyone what the best film ever made is, and unless they say Jurassic Park, they are wrong. Sure I watched it when I was an impressionable seven or eight year old, and sure I’ve always loved dinosaurs, and sure I worked for years at the Natural History Museum, but biases aside, it is the best film ever made. The T-rex chase, the raptors in the kitchen, Nedry getting eaten, it’s got everything and film could want. 

Wait, this is a RC car forum, why are you talking about a film franchise that’s not released a great film for 32 years? Well my friends, welcome to Jurassic Park Jeep build.

The car in question is a Taiyo Jeep renegade from 1985, just like me. If anyone wants more information there’s loads here:

https://rctoymemories.com/2012/04/15/tandy-radio-shack-jeep-renegade/

The goal here is to make the Jurassic Park Jeep (ignoring the fact I’m going for a 83 Renegade vs a 93 Wrangler) and add lots of extra bits to make it the best toy grade car ever released. I want to keep it all in the spirit of a toy grade from the era, so I’m not going to remodel it all, otherwise I might as well just drop the body on an FTX. This will mean adding an ESC, a working winch, new tires and a way to change gears via the receiver. Hard spare tire will be replaced with working spare too but keeping the bare bones quite stock.

The original had fully proportional steering and a three speed gearbox (imagine that on a toy grade now) which you could change via a switch on the car. I want to add a mini servo so you can change gears whilst driving (although perhaps not on-throttle) which will make it a hoot to drive around. I am going to try the Turbo Racing P32 radio – which is a budget radio, but does have four channels. The 3^rd channel is an on/off two-way switch (which will operate the winch) whilst the 4^th channel is three positions, with adjustable EPAs, so I’m hopeful that will operate the gear select. Hopefully this thread will help anyone with a Tamiya three speed who wants to see if a cheap wheel based radio could work as well.

With two wheel drive off road ability will be limited, but there’s no rear diff, and it’s very light, so with good tires it should be able to push up slopes and sticks and stones, if not crawl.

I also want to explore a new bumper, which should help the approach angle, as well house the working winch.

For this I’m going to need:

The car

New tires

Decals

Paint (red and beige)

New electronics + micro Servo + winch

This is what it looks like stock, next to the Scorpion. I'm not quite sure on the scale, I get roughly 1/11.3 in my calculation, which kind of fits into my fleet. The plastics are in great condtion.

 

Hard to read, but the tires say Goodyear. They look amazing, but have zero grip and the rubber has just gone completely. It's a shame as they are really nice otherwise.

Lastly for this evening the gearbox. 

The little lever sticks out of the bed so you can select gears. A quick way of doing this would be to attach something on the bed that moves this lever, but I think I can do better than that.

When I take off the gearbox cover you can see the lever attaches to this large white plate which moves left to right changing gear. There is just enough space between this plate and the rear of the car to place a small servo, which could then do the gears. I'm not quite sure how to do this yet, but a servo arm connected to a rod connected to the plate should give a L-R motion is it goes through the vertical, keeping all the motion in the same plane. 

Another option would be to run a channel going vertically on the plate in-between which a small nub on the end of the servo arm sits. As the servo moves through the range it forces the the plate in the same direction in the x axis, whilst the nub can move up and down on the y axis without impediment. This has nicer geometry, and only applies a force in one direction on the plate - which does have an appeal.

I'm not sure which ones is better?

I also need to work out how to stick the servo down. Space is going to be quite tight, but I think it should be possible.

 

 

[MadAtComputer 113]

I love the look of the Jurassic park jeeps. I also love the original movie. I wore out at least one VHS of it. I still have the second copy lol

[Nikko85 4209]

Thanks! I am taking liberties with this with both the model and year but it will still have that JP feel.

I realised I needed to create a servo bracket, so have designed something on my free software to print tomorrow.

After some deliberation I think a servo horn and push rod seems to make sense. 

The somewhat annoying thing is that from left to right the gears go:

M-L-H

So there is no smooth way to cycle through L - M - H. In reality I won't be working up the gears, but choosing the right gear when I change surface.

The good news is that the little winch seems to work on channel 3! One press for out, press again for in.

Will 3D print tomorrow and then updates for all.

[73robb 139]

I'm doing similar on a CC-01 Wrangler, still very in progress at the moment and has been for the past 12 months 

[Nikko85 4209]

Lots to update but long story short, it works!

I printed a servo bracket to hold the servo. 

This was attached to the chassis  with two 2.5 mm screws at the bottom. It feels solid. First time ever I got the print bang on first time!

A tight fit! I then added a solid rod to attach to the gear selector. Getting the radio settings was tricky, although you can change the EPA it does both ends at once, so it takes a little tweaking to get all three gears aligned.

Once set however it works well...

Back with the cover on. Now this lever is more of an indicator.

Next up was the steering. Thankfully these taiyos had almost full sized servos in the originals so not at all tricky to swap. 5mm ball joint sits on the white plastic channel and moves the steering rack.

I cut away a little plastic  to increase the steering throw.

I quickly soldered on some 4mm bullets to the motor and it all works nicely. It's cool to change gears as you drive, and I am slowly getting used to how they work. Changing seems to be smooth. 

Next up is the winch, tires and wiring / battery. There's very little space for anything as the interior sits very low so will have to carefully sort out locations.

Very happy it's working well. All gears seem to engage nicely, I am a little surprised to be honest.

 

 

[ad456 549]

Just awesome. 3d printing can really make these conversions a lot more straightforward!

I’ve got a Tandy Turbo T in the loft and am always tempted to do this kind of conversion when I see your threads. 

[Nikko85 4209]

On 3/15/2025 at 9:40 AM, ad456 said:

Just awesome. 3d printing can really make these conversions a lot more straightforward!

I’ve got a Tandy Turbo T in the loft and am always tempted to do this kind of conversion when I see your threads. 

Do it!

A tiny bit more done today, I added the winch and sorted the bumper. I moved it in and cut a little groove in the bumper so the body can slot in when the winch is attached. It took ages cutting down and trying different solutions. In the end I 3D printed some mounts that slot into the bumper and attach to the chassis. I can print in different sizes if needed and also being the bumper up or down so there is some flexibility.

We end up with a smaller bumper that looks a lot more realistic and scale. It's higher and closer in so will get much less caught on things. With 2WD and zero suspension this is not going to be great off road so every little helps. 

Winch is cool! Looks the part and actually works. Nice to replace the fake on with a real one! One press for out, press again for in.

Still got lots to do: 

Making the doors

Painting the car red and wheels red

Masking and painting the right parts beige

Make a driver

Wiring and electronics

Sort tires

But it's been a fun project so far. Far slower than some builds, mainly as I have to drill 40 year old chassis and don't want to make a mistake, so trying to really think before doing something.

 

[Nikko85 4209]

Spray painting went ok. Couple of tiny spots I could redo, but it's going to get chipped anyhow.

I painted it all red to get a nice texture before going with the beige.

Next step is the doors, spare wheel, jerry can and stickers.

 

 

[Nikko85 4209]

Almost done.

Sticking on the doors is proving tricky.

There is a lip to the doors I can stick them to, but I stupidly painted first it all first. When I super glued the paint came off so it didn't really work. I also used very small amounts of glue, not wanting the glue to run and ruin the paint job.

For now the doors  are taped on from the inside, but it won't last, so I need a better solution. Some thin strong double tape on the lip should work.

That issue aside it's looking good. I went with 72mm crawler tires, which fit the wheels perfectly. I replaced the plastic spare tire with a real one, printing a little part of the spare wheel to keep them on.

Working winch is cool. To have to careful not to wind in too far or the rope snaps.

Fake plastic tire now a real one. Unlikely to get a puncture but it's a cool touch.

Doors are 1 mm plasticard cut to size. Going to explore a few options for sticking on properly. A tiny hinge and magnet to lock to make working doors considered.

Will have to be more careful of raptors if the doors work of course.

Overall it is looking good. It's not a great driver, but has a certain charm! Decent ground clearance as the wheels are right at the bottom of the chassis so the 72mm wheels are used well.

I still need to

Cut indicators and other lights from vinyl

Make a driver

Sort out the on and off switch 

Find a proper solution to the doors

 

 

[JimBear 1307]

If I were a raptor, I'd be all over this one!

Good work, man.

[Nikko85 4209]

16 hours ago, JimBear said:

If I were a raptor, I'd be all over this one!

Good work, man.

Thanks!

All pretty much done now. In the end I just carefully applied more glue and pressed the doors down hard, it seems solid and looks fine but....

...the truth is I really hate gluing...

Not all glue, but when I build my goal is always to make something that could have come from a factory. The second you add glue to me it always seems like a bodge, something that looks good till you look too close.

In part it's also because I could rip the doors off. Now in actual use it's unlikely they'll come off but for some reason knowing they could be pulled off if I tried makes me less satisfied and they feel more temporary. If I was gluing something with a large surface area I can walk away knowing that's a permanent bond, but this.....it's a fix, but feels more like a fix than a design choice.

Anyway, door fixing aside, I am happy with how it's turned out.

I added an extension to the on off switch then added a new switch the location of the original.

This makes me happy.

Doors now flush with the body at least!

Drives ok. It doesn't have a great steering throw, but would be great for park tracks. Its pretty small and light at around 1kg.

Top speed is hard to tell, I will test run tomorrow. Won't give any tamiya a run for their money but fun to drive around and change gear!

 

 

[MadAtComputer 113]

Looks great! I really need to fine a jeep r/c