way to make alum. less flexible

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Mitchg07261995

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Is their a way to make aluminum less flexable? Im currently designing a chassis for a Losi 1/24 scale short course truck that is electric powered, so that I can use power from a tiny internal combustion engine called the Cox peewee .020. I have the main shape of the chassis complete as you can see
FJBvlXnl.jpg

This pic was taken from what I drew up a couple weeks ago, since them I have found all the angles for the triangles
My plan is to make it .100'' thick. Is this thick enough to be rigid and be able to resist flex or bending from driving, or jumping the car? I hope to throttle the engine and gear it so that top speed is around 15mph
thanks
 
I feel that you will be OK with .100" thickness. The main method used to stiffen panels is to put some sort of crease in it, you may have noticed large pieces of sheetmetal used to make things like air conditioning ductwork etc. have a "X" crease in them. This adds stiffness to them and takes out any spring.
If you look under the hood of a car, there are lots of brackets with ribs in them, this is another method of using thinner metal but still retaining strength. The panels on a car body are shaped to have creases in them to make them more rigid, it's not just for a good look.

Paul.
 
If you make it thinner fold up the edges and stategig creeases it will be lighter and stiff.
or glue on ribs.
Pretty much what swifty said.
Tin
 
When I was in the sign business there was a grade of aluminum that was quite stiff as far as aluminum goes. Street signs are typically made from it to resist wind deflection and they are about 0.1" thick. Perhaps there is an old sign to be had somewhere.
 
Honestly id go a bit thinner and bead roll some ribs in it for strength.
 
Or find some graphite sheet. Much stiffer and lighter. It was used extensively on 1/12 scale RC cars and was usually in the .0625" range of thickness.

Steve C.
 
Or find some graphite sheet. Much stiffer and lighter. It was used extensively on 1/12 scale RC cars and was usually in the .0625" range of thickness.

Steve C.

We use 2-3mm carbon fiber on RC helicopters for stiffness and light weight. It is both stiff, light and very expensive. Also a pain to machine. Dusty and wears out cutters (even carbide) to beat the band.

John
 
Yup, been there! Stiil can't be beat for strength to weight if that is what's needed.
 
.100 is overkill for a Pee Wee .020. Thinner with bends or creases or composite is what I would do.
 
I showed my print to my teacher today and he thinks i should go down to .050''
 
.100 is overkill. but .05 is marginal in my opinion. it is possible but you will need ribbing. you could make a compromise and go to maybe .075 with ribs and drill lightening holes. you could make dies to bevel the edges of the holes for more rigidity. you may want to start with aluminum that is annealed or "O" condition. or atleast not fully hardened then have it heat treated when complete. tin may know how much you can bend hardened aluminum before softening of stress relieving is needed.
 
look at a 1/10 losi chassis or rc10gt. they are aluminum not much more then .062 thick. for a losi peewee then i would think .062 would be fine. just add some braces for front. Once it is all together i bet it wont flex. bolt on tranny, motor mounts and servo plate for mounting servos you will be fine. servo plate buy itself would add needed strenght.
 
Hi,16g 0r 1.5mm is fine you can only use std gauges or metric 1,1.2,1.5 2 etc
You can easily stiffen larger areas by bonding 3mm plywood or fold top had sections an d rivit
on to support motor etc. From a very old sheetmetalworker who has forgotten more than he knows
make it and iron out any weaknesses as you go.NO DESIGN HAS EVER BEEN SPOT on FROM THE WORD GO
Regards Barry
 
ok, ill make the chassis .062'' thick :)
I picked out a body for the car, here is the body sitting on one of my 2 losi 1/24 scale sct's
R97H0wIl.jpg


the body is from a 1/25 scale revell 1969 corvette 427 kit that i got at good will
 

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