3DP material for RC methanol fuel

[petertha]

I'm considering getting a carb manifold adapter printed by a friend who has a 3D printer because the shape is kind of funky to machine. Its mostly to evaluate the carb itself so not really intending long term use. If it works out I'll machine a permanent one from bar stock. What kind of material would be advisable for typical RC fuel? (methanol, nitromethane, oil).

 

[Asm109]

Nylon would be a good one to look at. Chem compatibility should be good. Its probably a bugger to print.

 

[Nerd1000]

I'm considering getting a carb manifold adapter printed by a friend who has a 3D printer because the shape is kind of funky to machine. Its mostly to evaluate the carb itself so not really intending long term use. If it works out I'll machine a permanent one from bar stock. What kind of material would be advisable for typical RC fuel? (methanol, nitromethane, oil).

PETG should work so long as the temperature is below 70 degrees.

 

[Peter Twissell]

Print in any convenient material, then paint with fuel proofer.

 

[CraigLD]

Another possibility would be ASA (a derivative of ABS). ASA is my goto filament for a variety of applications where the result will be used outside.

 

[KennyMcCormick315]

I printed a fuel tank for a Norvel 061 powered 3D printed airboat project and it didn't care. No fuelproofing done, standard Monoprice PLA+ on a Monoprice MP-10 Mini printer at standard PLA print settings. That print was aaaagggesss ago...nearly a yaer ago in fact...that fuel tank is fine. No signs of degredation.

Glow fuel doesn't eat PLA like people say it does. Maybe over decades it might, but not in anything resembling a speedy manner. I'd almost bet money you could print it in PLA, then run your 3D printed intake manifold long term without any issue so long as you don't overheat the engine. Certainly long enough to test fire it like you plan to do.

Fun fact I even printed the engine's beam mount out of that very same PLA. It failed because the slicer didn't correctly change from normal 20% infil to the 100% infil I told it to use, so when the screws were tightened in they just sorta crushed the beams, cracked them.

Some bench testing I did and caught on camera.

 

[Nerd1000]

Another possibility would be ASA (a derivative of ABS). ASA is my goto filament for a variety of applications where the result will be used outside.

Just keep in mind that ASA is very much NOT tolerant of non polar solvents like petrol (gasoline in freedomspeak) and engine oil. Nitromethane, methanol and castor oil might be ok because of their more polar characters.

 

[Bazzer]

PLA is fine for methanol and nitromethane, just drain the tank down at the end of the day.

We have won a lot of competitions in RC pylon racing in England with 3D printed fuel tanks, yes you have to be slightly more careful but in the case of this model/engine combination the freedom of design given by the 3D tank solved a fuel head issue.

 

[petertha]

Thanks for info @Bazzer.
BTW, that looks conspicuously like a Club-20 pylon model, is it? I used to race them in the winter to keep the (slightly frozen) thumbs busy in the off season.

 

[Bazzer]

Yes it is a Tracer, we fly them with 32's now just with a silencer, it is great fun. I also fly CL speed.

The photo is of the three models that I have competed with this year
.

 

[Bentwings]

castor oil even degummed is very messy it does smell nice. It does not remove easily and is very sticky when cold I have a full quart in the freezer I was planning some test on steam engines but I’ve given up on that for now as I I don’t need it now castor oil istill used to break in aircraft engines from what I’ve heard
Just keep in mind that ASA is very much NOT tolerant of non polar solvents like petrol (gasoline in freedomspeak) and engine oil. Nitromethane, methanol and castor oil might be ok because of their more polar characters.

 

[Bentwings]

I ran nitro top fuel dragster funny cart and alcohol funnycars . The fuels sr really corrosive . After each run we ran the engines on non oxy gasoline to purge fuel out of lines and engine . Then we disconnected all fuel lines and drained remaining fuel out usually a spray of marvel oil air tool oil was enough to finally clean. Seems like a lot but losing a round due to leaky fuel line was very economically a big mistake often in the thousands of dollars . Technically we could have just tossed fittings and used new
Just keep in mind that is very much NOT tolerant of non polar solvents like petrol (gasoline in freedomspeak) and engine oil. Nitromethane, methanol and castor oil might be ok because of their more polar characters.we had a portable gas tank with quick connect fittings there were no plastic fittings O rings were critical so we used lots of them just for the fuel the throttle valve was very sensitive so these were changed every race day. I used nitro in my pattern planes as I used ducted fan engines again model fuel lines were not the best so I went aftermarket to Parker co. They directed me to recommended o rings and fuel line materials . It’s been a longvtimecsoni just don’t remember exactly what was used they have pages of specs available so it’s pretty easy to select the correct materials I only used non oxy premium gas in my giant scale planes and yellow Tyson fuel lines standardcrc tanks worked fine. I did change fuel lines often just to make sure also I used standard Klotz two stroke oil Various ratios generally 40 to one.

 

[Bentwings]

Oh dear spell check did it again I’m realy sorry I carefully checked but it just changed when I posted . I don’t see well but I thought I made all corrections