High speed RC project

[bez 9]

I have been busy printing away with my UM2 and I think its about time I share with you all what I have been up to

My main hobby is RC speed racing, I've just finished competing in the UK round of ROSSA (remote controlled scale speed association) with my car which is dripping in 3d printed goodness.

The chassis is my own design, and all the plastic parts have been printed using my UM2. There are some piccys:

For those who are interested in RC the current running spec is as follows:

ESC: MGM Compro 400A 63V

Motor: Lehner 2240 6 wind

Cells: 2 x 4 cell turnigy nanotech (in series)

Radio gear: spectrum

Chassis: custom design by myself

Body and plastic parts: custom designed and printed on a UM2 (using dutch orange pla/pha from colorfabb)

Current high speed: 133Mph (at 80% throttle - few technical gremlins)

I'd like to thank the UM Forum veterans for a lot of help and advice along the way with my printing hiccups along the way.

I will keep this thread up to date as I make progress with the project

Edited September 19, 2016 by Guest

[DidierKlein 729]

Very cool stuff nice work

 

[drayson 75]

GREAT!!!

Congratulation, its a real beauty.

[woofy 12]

Very nice car,

and Wow! that's some serious power you're dumping into the wheels. I guess traction control is down to your thumb on the stick :smile:

 

[anon4321 16]

That is sweet. The body looks like it was commercially made! 133MPH? Real not scale speed? WOW!

Now we need VIDEO!

 

[bez 9]

Thanks for the comments guys. Yeah real speed not scale, Its like threading a needle and thread trying to get through the speed traps at that speed lol.

One of the other guys that was at the event got a good video i'm just waiting for him to upload it ... wont be long i hope

I the meanwhile this is what exploding foams do to pla/pha lol

 

[skint 61]

Awesome, agree lets see it in action!

 

[anon4321 16]

No!!!!!!!! that sucks. You might try colorfabb XT. Less brittle/more flexible but that sometimes requires thicker and heavier shells.

 

[bez 9]

That was my spare cowl too, the other one had an argument with a pothole. Which means I now have a solid 80+ hours ahead of me re printing the body lol

I did try the XT filament but it was warping quite a lot. I really need to make an enclosure for my UM2 as I'm finding the ambient temperature changes are throwing the quality out of the window.

 

[gr5 2,172]

Do you mean "expanding foam"? There is a product called "great stuff" which is an expanding foam. It comes in different color cans. One of the colors has zero expansion. In other words it stops expanding before it hardens. You want that one. I think it says something like "doors and windows" because the expanding version will warp window and door frames.

 

[conz 0]

Do you mean "expanding foam"?

 

I think his foam tires have done that. For 133Mph they have to spin very fast, and in case of a defect that is a lot of energy, like a little explosion.

 

[gr5 2,172]

Oh! Makes sense. Those tires get very hot at 130MPH! Well I would recommend a design that lets you print only the wheel covers as a separate print.

 

[Dim3nsioneer 557]

Formula 1 problems... :cool:

 

[bez 9]

Its not really the heat that kills the tyres, its tiny stones on the track. All it takes is a tiny cut and the centrifugal force just instantly skins the tyre and the chunks of foam are ejected from the wheel with enough force to rip through 1.8mm of pla :lol:

This is one of my wheels after a foam exploded:

 

[electronic_matt 0]

Bez that looks awsome!! where abouts in the UK are you?

 

[bez 9]

Cheers I'm based not too far from Ascot.

I'm still waiting for my mate to pull his thumb out and upload a video, that will teach me not to set up my own camera lol

 

[DidierKlein 729]

Tell him you have a big community waiting for that video and that we will come to visit his house with nerdy weapons if he makes us wait longer :mrgreen:

If i still had time to play with my RC car (i used it for drifting) i'm sure i would get a lot of use of my Ultimaker it seems well suited for this kind of use

 

[bez 9]

lol, the phrase "don't make me 3d print a gun and bust a cap in yo ass" comes to mind lolololol

Yeah I think 3d printing has a good home in RC especially in scale stuff. Makes me wonder if its possible to print a engine bay ....... but that's just time i don't have to sink into the full on session in solidworks lol

 

[bez 9]

The video is here, just a quick warning of the swearing at the end of the video lol

 

Edited September 19, 2016 by Guest

[DidierKlein 729]

Finally

It's so silent (except the swearing :mrgreen: )

 

[Dim3nsioneer 557]

#### me as well! Great! :lol:

 

[gr5 2,172]

Lol!!! Love the video! Are you the guy in black (up where it's safer) with the controller?

I thought it was going to be some massive amount of editing with music and stuff because it took so long to post, lol!

Seriously - thanks for posting that video. I think I watched it 10 times.

 

[bez 9]

lol yeah that's me. More for line of sight that safety haha

Na unfortunately my mate has been rather busy took long enough to get him to upload the raw clip, you gotta love the welsh lol

 

[apollott 0]

Now we need someone with a 3D printed plane to come over to your race track and find out who is faster.

 

[bez 9]

I thought as it has been an age i would update this topic.

Looking back 2014 is a loooooong time ago lol

The guys at Ultimaker took an interest in the project and the car went off on its travels around the globe and the feedback I good from the project was overwhelming and humbling. I wanted to try and up my game a bit and following my last build I thought I would focus on making the car more 3D printed than before.

This would mean a complete re design of the car and the dangerous ground of the unknown. So I set about coming up with basic chassis designs and I finally settled on a chassis reinforced with carbon rods. My main goal was to come up with a design that was super strong and that could be easily built from readily available supplies.

The design was split up into 5 sections, the nose cone, 2 body sections, a motor section and the diffuser/tail. All including the main chassis and body in a single design. I tried to keep the design modular so should one section have issues it would be less time intensive and mean that if one part failed (which was likely) it would mean not writing off the whole chassis.

Following a few bugs I've had with the previous version:

- I upgraded the rear bearings to larger 8x16x5 and used 4 instead of 2 and upgrades the axle from 6mm to 8mm. This was to reduce the stress and heat on the axle breaings. Another benefit of using a 8mm axle was I could use a 17mm Hex fitment which would open up a wider selection of wheels and tyres.

- I also went for a 16mm wide T5 pully and belt system to reduce the backlash in the drive line.

I planned to use the same electric configuration as before so I could make a comparison to how well the new chassis held up compared to the old version.

This was how the design turned out:

With this design I left the rear tyres on the outiside of the body to reduce damage to the car should they fail. I opted for GRP Velocity's which are rated for over 160Mph.

So off I went for my yearly ROSSA meeting to run my brand new car ............ however this year luck was not on my side. I think one of the tyres I fitted had a slight defect and during testing it let go in a big way ........ It ripped the axle carriers out of the chassis, bent a 8mm Silver steel axle and even managed to snap both wings off (still no idea how it manged that one lol)

So its back to the drawing board, I haven't given up hope on the 3D printed chassis but I believe I do need to make a few more revisions and I certainly wont be using those tyres again lol.

Fingers crossed it wont be so long till I update this thread again but one thing is for sure the project will be back and all going well stronger than ever