Jrx2 Proformance Kit proto car from 1989 ROAR nats replica

[highwayracer]

Anyone have better pics, any more information, or contacts to confirm authenticity?

Jay, there was a thread last year of a car that a new member had...that looked authentic. I believe even Rich said it may be one of theirs. It looked just like the one I saw (and had in my hands) back in 89.

Regards,
Roger

[JK Racing]

Anyone have better pics, any more information, or contacts to confirm authenticity?

Jay, there was a thread last year of a car that a new member had...that looked authentic. I believe even Rich said it may be one of theirs. It looked just like the one I saw (and had in my hands) back in 89.

Regards,
Roger

http://www.rc10talk.com/viewtopic.php?f=27&t=30458

[mrlexan]

Thanks guys. I'll start a thread and take individual component pictures. Maybe I can get Rich to review and chime in as well.

[Jirka]

Finally some progress...

In 2012 November I made first chassis parts out of thin acryl sheet.

The white papers are just represents 7-cell long battery pack and as big servo as it would be possible to fit in servo area. The side rails are about right - they are just a bit higher than "battery box" in rear bulkhead. The part in front of battery, lest call this "middle bulkhead" is a bit too thick and because of this the "X-part" is too short and it is also a bit too beefy.

About year later, very late November 2013 it started to get cold in here. I had to start do parts if I wanted to something to do during winter time.

The first thing was to cut from white nylon sheet (thanks Jerzi!) the middle bulkhead to right external dimensions and so that all angles were 90-degrees. I did this with miter saw that I have from our housebuilding project and also with blade that was meant for wood. The machined surface was so much better than I ever expected, it is like factory made . In the last picture You can see the temperature in celsius from my mobile phone. I did also cut with same machine and blade carbon fibre (from that mammography machine) siderails. The blade was a bit aggressive and the cottage where I made this was full of flying individual carbon fiber sticks.

1st December 2013 it was time to test first parts to chassis:

It was also time to deside that I do a replica from Jack Johnson's 1989 ROAR nats winning car. All those Proformance Kit proto cars seemed to have small differences in chassis parts and in Jack's car the lightening holes in siderails were squares.

Jirka

[Jirka]

Then I started to do correct looking "X-part". That was so far the hardest thing in this project. I made maybe 6 or something of them before I managed to make one that looked like it should. These two were not good enough:

Then finally the pink from carton one was close enough and I started to cut carbon fibre using it as a model:

The "X-part" started to get it's shape. Only hacksaw and a hand drill was used to get it this far:

Mid January2014 and side rails got their lightening holes:

Side rails are now practically done and so is also the "X-part" except it still needs small curves to rotate front shock tower. Below are some of those "X-part" experiments:

Jirka

[Charlie don't surf]

Wow Jirka- Great stuff, love the hand fitting of the parts

What's next with the car? (-6c...too cold )

[Jirka]

Like I wrote in last page, I managed to get a Tekin PXT 600 Pro that should work according to the seller. But since I will not never drive this car I will never find it out. The receiver plug is incorrect Futabe one, I need (according to my knowledge) Airtronics/Sanwa wire with two black wires with one red wire. Also the blue wire to the motor is way too short so one blue wire with correct AWG and Tekin text in it is also needed. Tekin 600 Pro was one of the first ESC, but not the first, that used mached FETs. More about this ESC can be found here: http://classicrc.wordpress.com/esc-electronic-speed-control/tekin/tekin-pro-tempfet/ and here:

The next steps in this project will be:
- drill holes to rear bulkhead for inner upper rods by using JrxPro rear shock tower as a template
- drill holes to rear bulkhead for side rail mounting
- drill holes all around to middle bulkead
- drill holes to motor plate
- drill to that new full graphite chassis (OMG what I need to do ) cell slots and curver to make Jrx2 body fit it
- to find the rest needed parts
- to find all needed Pactra paints (didn't they use pactra at Team Losi factory that time?)

Jirka

[Jirka]

Wow Jirka- Great stuff, love the hand fitting of the parts

What's next with the car?

(-6c...too cold )

I do not like them. They look better in pictures than they really are - hand made parts are always hand made, all a little different or some small things are not like they should. I will never ever start doing this complex parts from scratch with only hand tools.

My old race car: Yokomo YZ10 94. It's "brother" is here: http://www.rc10talk.com/viewtopic.php?f=27&t=23418&p=232428. After that Corally SP12 and then... I have something in mind.

The problem there was that I couldn't use gloves and sleeves had to be pulled up. If the gloves or sleeves would have touched the blade it would have been my last time to use any tool.

BTW: It is -18 now outside.

Jirka

[Jirka]

Some progress: I got misc hardware, some to this project some to future Losi project(s).

Those nuts and bolts are not the biggest issue this month but this is:

I managed to be the first or second to purchase one of these Jrx2 repro bodies a few weeks ago from ebay that are done with original Jrx2 body and wing molds. The box come with body and wing that both seems to be covered with protection film. There was also window masks and certifigate with Pop Losi's signature that really look like hand written . Next, something exciting: Something about the quality and size of this repro body. First cutting lines and details:

All cutting lines are highly visible as is the text in rear end, much better in real life than in these pictures. I took these pictures with flash light that I found out to be the best method to show them.

And then to the size question that seems to be always an issue with repro lexan bodies:

Since I have one original Jrx2 body, I did drop it over this repro body to see possible differences. Both bodies are so equal in size that the front nose area of the original body outside did not even fit nicely over repro body. Then the same but opposite way, original inside repro outside:

Bodies does stack this way the same way as they do stack other way around.

And then one test more:

Here the repro shell is upside down and I did put the original shell in to it. They fit nice again.

So I am very pleased with this repro body.

Jirka

[JK Racing]

If those are the bodies from Gary Keyes, its not a reproduction, they are front the original mold (my understanding), so they are more of a re-release of the original body.

Get on the with the build!!

[Jirka]

If those are the bodies from Gary Keyes, its not a reproduction, they are front the original mold (my understanding), so they are more of a re-release of the original body.

Get on the with the build!!

Yes, that is the same Keys (father and son?) bodies made with original mold. The mold still seems to be in good enough condition and Lexan back then and now behaves the same way.

I just have been more than busy during this winter season and life still seems to be very hectic in future, but I will do my best to steal a little time every now and then to this project. Next steps to this project are:

- Some imperial drill bits (have to order them from US, no-one sells them here no more).
- I have to visit Niki, he has drill press so I can drill holes with it to rear bulkhead to camber links and to the "middle bulkhead" about accurate.
- Get paints to the body. Can someone help me with the Competition Plus cover scan with better quality picture? I think the red areas are just plain red, but they seem to have some purple areas also. Those purple area also appears in some RCCA pictures too. I think that there are not purple areas in really, but just to be sure. Also are there small gray stripes between blue stripes and red areas or not? Is the grey that Jack used metallic or not (impossible to see from the pictures)? Are Pactra (I beleave they used Pactra paints at Losi factory) paints now and late 80's how close to each other?

Jirka

[Jirka]

Some progress from last few months:

The cell slots here/below are not done 100% yet, that are a bit too narrow and all not in line:

The car looks like this now:

Jirka

[Jirka]

Cells fits really nice between cell slots and the carbon fibre "battery support stick".

Jirka

[scr8p]

looks good so far!

[DerbyDan]

Great updates Jirka & very neat work - those chassis are so difficult to cut/trim or drill neatly!...

You can really see the development work (from the original prototype) that eventually found its way into the production Jr2/Pro SE but in the form of a molded chassis.