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ThunderDragonCy

Project RR-03Ra - Converting a TRF201 into a rally car

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Yes you’ll need very short towers. I’m not sure if the whole rear gearbox won’t get in the way.  

 

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Jumped in and bought the RS200 shell anyway. Arrived today. Its quite lovely, and comes with way more stickers and accessories than I expected. Great value

Project Tamiya RR-03Ra RCON Ford RS200 body

So the key thing here is "will it clear the chassis?" At that back I am very pleased to say I think we are on! 😁

Project Tamiya RR-03Ra RCON Ford RS200 body

Tower doesn't quire reach the shell, motor mount clears the rear bumper. I doubt the full motor guard will fit but I think I will cut a spare to act as a 'sump guard'. 

Front might be a little trickier

Project Tamiya RR-03Ra RCON Ford RS200 bodyProject Tamiya RR-03Ra RCON Ford RS200 body

Its possible I might steel the few mm I need with ball nut shock mounting, but I suspect I might need a new tower. The front shocks are currently 70mm with the long eyelet so I can put the short eyelet for 64mm and design a 6mm lower shock mount in carbon. This will bolt on easily as I have the camber mounted to the tower now too not the tub, so it's doable. 

Still a bit stalled waiting for Tony's Tamiya Parts special order from Japan for the final few TRF201 parts and the slow boat from China for the cheap rally wheels I bought about 2 months ago! Hopefully both will be here soon thrn I can see if it works as an rc car thrn look at chopping the tub and mounting the body. 

 

 

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I didn’t know they were for sale now - where did you buy?! 

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3 minutes ago, Kevin_Mc said:

I didn’t know they were for sale now - where did you buy?! 

They were only released this week. I got mine from racecraft rc in the UK. RCMart have thrm apparently. 

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Great build! Hope you can fit the front tower somehow

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Small update. Finally got some wheels sorted. These gorgeous Tamiya Focus WRC wheels will go nicely with the RS200 shell

2019-03-16_05-07-25

They have quite large internal ribs so I have ordered some 7mm hexes to make sure they clear. 

Related, I bought another set of wheels because it was cheaper than buying a set of tyres, but good to have spares. And thry are orange, which everyone knows is The Best Colour (tm) 

2019-03-18_08-06-52

Was nice to finally get it on some wheels and see how it looks. Track width on some spare 5mm hexes was around 184mm. These wheels don't have the ribs like the Tamiya wheels or have more offset, not sure which. Anyway, seems I have some scope on track width and still get thrm tucked under the shell. 

Unloaded ride height appears to be around 22mm, which seems entirely acceptable to my buggy sniffing sensibilities, but possibly a bit high for a rally car? Will have to play with springs and see how it sags once it has all electronics, motor and body on board. 

Wheelbase 277

Project Tamiya RR-03Ra. Pre chassis cut wheelbase. 20mm to come out.

So 20mm has to come out of this roughly 50mm parallel section of the tub. 

2019-03-18_08-10-13

Going to strip the tub out tomorrow and take it to the engineering company next door to work. See if they have any chop saws that might make short, accurate work of sectioning the tub. After that I can measure and draw up the shapes of the carbon fibre plates I will need to order to stick it back together again. 

 

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The white wheels are the same as the set i have for my grey one - good choice. Where did you buy them?

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Just now, Kevin_Mc said:

The white wheels are the same as the set i have for my grey one - good choice. Where did you buy them?

His Royal Tonyness of Tamiya Parts on ebay. 

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I thought you might have, i’m sure that’s where i got mine’s from 

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No going back now!

Project RR-03Ra

20mm parted out of the tub. I'm measuring up to get some carbon plates to fit from fibrelyte, and seeing as I'm ordering from them, an extra few quid will get me a lower front shock tower so I have been laying that out too. Paper Aided Engineering

20190320_163616

Designed to run 64mm mini shocks, and give better clearance to the shock body, plus a bit of roll centre adjustment too. Seeing as I'm on this I think I might add some dedicated body post holes as well. Any recommendations for their location? Outboard of the shock holes and a little higher seems to be how the XV01 works?

Cheers!

 

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Really love to watch your engineering. There are already enough shelfqueens out there.

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3 hours ago, Collin said:

Really love to watch your engineering. There are already enough shelfqueens out there.

Amen brother! RC cars are for driving and tinkering with. 

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Finished the insert shapes and front tower with body post holes and emailed them to fibre lyte. I have a TA01 set with an angle on one set of posts to put on the front tower. 

I think next stage is the bit I have been putting off and finally having a go at the ball diff so I can have the transmission ready to bolt up. 

Also this will end up brushless. I was going to do brushed but I already have a 13.5t motor on the way from China that was supposed to go in my SCT, then another option for the truck materialised. Suggested gearing for buggy 13.5 is 7 FDR, 4.5 for touring car. I measured the wheels on my TRF211 and the rally wheels and its 81 vs 71 diameter. So, I can gear up by at least the ratio in wheel size, so 7 x 71 / 81 = 6.13. I have a 77t spur in the spares box so I ordered a 34t pinion to give me a 5.9 FDR. Feels about right given on-road touring is 4.5 and my Thunder Dragon pulls 6.7 on a 13.5 really nicely. 

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Ok, get ready for a big post! Project RR-03Ra has almost reached completion in a single day! The shock tower and lap joint inserts arrived from fibre lyte, and after 8 weeks the TRF201 L and AA parts Tony Tamiya Parts special ordered for me also turned up. So here goes..... 

Project RR-03RA

I am using a composites two pack adhesive. You need to scuff up both surfaces to give a key. 80 grit sandpaper

Project RR-03RA

Inserts are glued to the floor of the battery tray and side pods. Long thin plates glued to the outside of the battery tray ribs (not the inside in order to ensure the battery still fits) and two short sections for the outside walls. Glue is pumped out if the dispenser down the mixing nozzle and thrn I mixed it a little more with some cardboard once applied. All parts pressed firmly in place with the centre bottom plate clamped in a G clamp and clothes pegs for everything else. 

Project RR-03RA

The nail varnish remover is what I use to clean everything prior to bonding. 

Cured after an hour

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I used 2mm carbon which is massive overkill but I didn't want it breaking. 

So now the chassis came together so quickly, there is the small matter of building a ball diff to deal with. 

Project RR-03RA

New reinforced diff gear and idler set, tungsten carbide balls, brand new yeah racing diff grease. Hopefully this will be the first ball diff I have built that lasts more than two packs. All done with fresh 1510 bearings. Not pictured, but as I am not going mad with the power I am using the DN01 non-slipper layshaft. Gearing will be 77/34 to give a FDR a little under 6 for a 13.5t brushless motor. 

Project RR-03RA

From here I reassembled the whole car. Transmission in place, and my new front tower is perfect. Bolted straight up, much better shock clearance and nearly 10mm lower than the 201 kit tower. There are square holes in the tower to match the ta01 angle body mounts. The straight mounts from the same kit are just bolted through the outer rear shock holes. 

Project RR-03RA

Trial fit of the RS200 shell

Project RR-03RA

Wheelbase is about right. It changes quite markedly due to the 25 deg kick up at the front but I am very happy with it. I used this to mark up the body holes and 6mm reamer them.

I trimmed the shell. I got some tamiya lexan scissors and they helped, but I am left handed so still some challenges. Wheel arches are quite horrible aren't they? 

Project RR-03RA

Tiny little detail is the motor guard doesn't fit, so I cut the used one I have spare to create a kind of 'sump guard' under the motor. 

Project RR-03RA

I am really excited about this. It looks even better than I hoped. 

I masked and got a couple of coats on the shell before it got too cold. Fingers crossed for finishing that tomorrow. The motor I ordered is still on the slow boat from China but I have a spare brushed ESC and 27t motor I can use to get it up and running. 

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Really like  how you've approached this, thought it especially brave to saw out that center section! I'd bet that it's stiffer and stronger now however with all that carbon.. looking forward to seeing the finished car 😎 

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1 hour ago, Grotty Otty said:

Really like  how you've approached this, thought it especially brave to saw out that center section! I'd bet that it's stiffer and stronger now however with all that carbon.. looking forward to seeing the finished car 😎 

Thanks. I guess it depends where your experience level lies. Once I had seen the TRF drivers from around 2011 parting two chassis to make a 13" wheelbase SCT I knew how to do it and that it could be done. I have some experience through work with selecting adhesives and luckily fibre lyte can accurately make any 2d shape I want so it was simply a matter of careful drawing up of plates, thrn printing paper versions to check fit on the cut chassis. The key was my friend next door at work. He has an industrial band saw with square jigs so had the means accurately part and cut the tub. I would have really struggled trying to do that with a hacksaw! 

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Got the chassis running today! I have a battered sand Viper shell from another member I cut down t on be a chassis cover. Also added some ford motorspirt wheel decals. Thank s @svenbthey look amazing!

2019-03-31_08-47-48

Can only fit a shorty battery but needs foam spacer. I had to cut down the 201 battery hold down. Otherwise it all went together well

2019-03-31_08-47-57

Its a little wayward at the moment but I have put stiffer rear springs on it. Hopefully it will be a little better. Finished painting the shell. Needs decals. 

 

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Finished today. Took hours to do the stickers. This fantastic shell comes with loads of amazingly scale decals, including a full set of lombard RAC rally replica stickers. I went for a bit of a mix. I didn't want to do a full replica or rally lookalike, and I love Ford Performance Blue. I added some silver stripes in a nod to the stripes on the period rally car. Masking wasn't quite perfect, but ok. Black window surrounds really help the scale look and it even has wiper decals! 

Project Tamiya RR-03Ra complete with RCON Ford RS200 shell Project Tamiya RR-03Ra complete with RCON Ford RS200 shell Project Tamiya RR-03Ra complete with RCON Ford RS200 shell Project Tamiya RR-03Ra complete with RCON Ford RS200 shell

I am sooooo pleased with it. Its just so cool. And the rally car ride height means general street running is no problem at all. The stiffer rear springs worked a treat, getting the weight of the rear end under control for really nice neutral handling. Some 700cst oil in the front dampers with TRF201 black front springs keep turn in calm but grip good. I have kept an eye on tightening the ball diff and it seems to be OK for now. Currently running a team xtremr 27x1 motor. I got it thrown in with the DB01R I bought, and just thought it was a cheap motor, but it's pretty punchy. I briefly swapped in a silver can when I had a body/motor lead clash issue and its MILES slower than this motor. Still going to stick the 13.5 brushless in when I get it, and using the tble02s ESC already, but this is good. Already rolled it a couple of times, but generally if you are gent e on the brakes it's really easy and fun to drive, just like I hoped. Got some gravel action too. 

I am calling it done. I'll update when the new motor in and if I get to run it on track. 

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Awesome mate, what an adventure. Very happy for you and for how it’s turned out, especially all the custom modding and experimental stuff. Very inspiring. Hope to see a longer video on that larger gravel area you’ve shot videos on before :) 

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