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markkat

Restoring and revamping my '85 Frog

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This is the first post on an ongoing process. During the lockdown, my 8yo daughter and I came upon my old Tamiya Frog in a box of our garage attic. I got it for Xmas in 1985 if I recall correctly.

This was the state of things:

YBfjPiQ.jpg

Organized, but dismantled. I couldn't recall why I had pulled the servos and the speed controller.

The mods I had last made over 20 years ago were a rear sway bar, bearings (of course), and a new gearbox and dog bone axles after my Kyosho 360 Gold shredded the originals. The two motors I had were the Gold and a Kyosho Le Mans 240S. That lexan body was also a replacement for the original.

I ordered a 3600mAh NiMH battery, and stuck the MSC and servos back in there. It looked sharp, and each run lasted for about 10 minutes before the solder on the MSC melted. The smell was nostalgic. :)

iiM2Uz6.jpg

After a fiddling with the MSC, and trying a resistor from an old dismantled Turbo Optima (the only other RC I've ever owned, but never loved), I ordered a Dynamite 60A Brushed ESC.

tpC3Xhh.jpg

You might notice the 4 AAs are still in there. It took me a bit to happily realize that I could lose them with the new ESC.

While waiting for the ESC to arrive, I discovered MCI decals. I decided to refresh the look, so I ordered a set of Frog decals, and a spoiler from RCMart.

Also, as the Frog's rear shocks leave much to be desired, I got some Boom Racing BRX01 Rear Aluminum Double Spring Shocks.

I think the new shocks and decals improved the look (the spoiler has yet to arrive):

Gd5eVjN.jpg

More of the journey to come...

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That’s a great looking Parma Chenowth body.

my recommendation, based on pulling my own original Frog out of my parents house, is to clean and rebuild your original, and then put it on a shelf. A lot of the plastic may have become brittle with age etc   

Then buy a re-release Frog and go crazy on that.

I ended up replacing about 95% of my original with re-release parts and spent more money doing it than it would have cost to buy a new ReRe.

if you have any questions, feel free to ask!

Terry

 

 

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Keep that body nice. In a past 5 years of OCDing my Frog, I’ve never seen one New In Bag...

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That does look good certainly a place on the shelf I think rather than running it

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20 hours ago, Frog Jumper said:

That’s a great looking Parma Chenowth body.

my recommendation, based on pulling my own original Frog out of my parents house, is to clean and rebuild your original, and then put it on a shelf. A lot of the plastic may have become brittle with age etc 

Thanks! It's great to know where that body came from. I always preferred the proportions of it.

As for the plastic, I thought that might have been the case, but have been pleasantly surprised. The only break I've had thus far was a cup on the steering rod. That reminds me, however. Upon adding the new shocks, I did add some fiberglass reinforcements to the rear arms where they attach. The twist on those arms was disconcerting.

lYQFLuO.jpg

Also, you can see in the second photo above that the front attachment for the left rear shock is a melted mess. That was the result of me trying to force a Kyosho Optima gold shock on it around 1987. It cracked, and I melted a repair. I've since got a re-re frame, and replaced that half of the frame. It's already an anachronism, I guess.

As for putting her on the shelf, I am not a collector, and it just doesn't feel right for me. There's something very cool about seeing my old Frog tear it up again.

Anyway, I put in the new ESC, and started to enjoy the new F/Br/R configuration. I did have to open my Futaba Attack transmitter and manually reverse the throttle control by re-soldering the wires, however:

Unfortunately, I found that after running with my 360 Gold or 240S motors for about 5 minutes, the car would start to drive at half speed. The NiMH was new, and it happened to both batteries I had. After some research, I concluded that it must be due to low voltage. In the process, I also disassembled, cleaned and reassembled my Le Mans 240S motor to no effect.

As the Dynamite ESC can be configured for Lipo, and as Lipo has a more squared voltage curve, I ordered a 5000mAh Lipo. (My 8yo daughter just got a Grasshopper, so the NiMH's have a new home.) I also picked up a 20T Dynamite brushed motor from the local hobby store.

To be continued...

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As I waited for my Lipo battery to arrive, I started to look at the positioning of what remained. It occurred to me that with removing the MSC mount plate, I could put my receiver in-line with the steering servo. I did this, and replaced the MSC plate with a square aluminum rod:

3j0Vewl.jpg

My thinking behind this was that any weight on the left was a good thing, to offset the large imbalance caused by the side motor position.

(You can also see a front-suspension mount, but more on that later...)

Looking at this setup, gave me an idea...

One thing I noticed as I drove my Frog, was that the front wheels are really pushed about. I believe that part of that has to do with the front suspension, but it is also a result of the car's center of gravity being so far back. Here's a video of an early drive that demonstrates that:

 

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Putting the steering servo and receiver in-line presented a re-balancing opportunity. My Lipo (and new motor) arrived, and voila:

7wlppWH.jpg

The Frog is almost completely balanced on the center line, and the center of gravity has been moved forward by nearly an inch.

More to come...

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It's great to see these old Frogs running again. My first rc car was a Frog. Years ago I found some new/old stock and replaced the worn out parts. Then i was too scared to run it. Luckily, the re-release came out and I bought one of those along with multiple sets of tires and another body set. Totally worth it.

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After improving upon the Frog's balance, my quest has become to do something about the front suspension. I think the stock suspension is genius, but it would be great to add some dampening. I did some research, but all of the damper modifications to the front suspension really detract from the look of the Frog, IMHO, and I wasn't about to cut the body to allow for mounts.

Currently, I am halfway to a solution. First, I cut some aluminum from my scrap Optima, and created a small front mount that didn't require cutting the body, or look out of scale.

Next, I measured the distances a damper would travel, and arrived at 38-45mm. I searched shocks and dampers with those dimensions, but that were also a small diameter. There aren't many, and I settled upon these "The Ultimate Mini Scale Shocks":

Z-S1686-1.jpg

They are internal spring, not oil, but I am determined to change that.

Here's what they look like mounted:

qZRyHJs.jpg

dwPy1ES.jpg

NwGStI4.jpg

KBLiyMY.jpg

I pulled the internal springs, so they aren't functional yet, but the travel is there and smooth. The lower chamber of the shock can be opened, and I am hopeful that a very small and flat o-ring/soft-washer will enable it to hold oil and still glide. Any suggestions are appreciated.

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13 hours ago, RichieRich said:

It's great to see these old Frogs running again. My first rc car was a Frog. Years ago I found some new/old stock and replaced the worn out parts. Then i was too scared to run it. Luckily, the re-release came out and I bought one of those along with multiple sets of tires and another body set. Totally worth it.

Thanks, RichieRich. I totally agree. There's just something about the Frog. What it lacks in performance, it makes up in character.

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