[BAracer]

Just building up a chassis for this year's Rug Racing GT3 Championship run on Carrera track...

   

This is my first serious sidewinder build, and I am aware of the issue of magnetic attraction/drag between the motor and a steel axle in this configuration. In fact, I noticed that the axle was rubbing on the motor casing to start with, so I had to smooth off some burrs to create an air gap between the two. However, dealing with that issue highlighted the magnetic forces present around this area of the pod, and which was made most apparent when I thought I had dropped one of the thin spacer I was fitting to the axle only to find it attached to what was now a magnetically charged axle.

So my two questions are: -

1. There seems no argument of there being magnetic attraction between my sidewinder motor and steel axle, but does that create magnetic drag, or at least create a pull on the axle that increases friction between axle and bushing, and therefore equate to a loss of performance?

2. I bought a titanium axle as a means of eliminating an magnetic attraction, but is the elimination of magnetic attraction to a steel axle lost as a performance gain by the use of this softer axle material which might provide less precise set up tolerances and be more prone to accident damage?

Have others experiences this phenomenon and felt the need to address it?

[OXO cube]

 I noticed that the axle was rubbing on the motor casing to start with, so I had to smooth off some burrs to create an air gap between the two.

just an FYI 

both Slot.it SIPA01 and MBslot MB23749 ( maybe others ) produce 'reduced centre ' axles 
this eliminates the clearance problem  between the motor and axle 
and i assume would reduce any possible magnetic drag ?


tbh jeremy , i only found this out recently when building MY 1st SW 
use them as a matter of course now 

Kev

[Kevan]

In an ideal world where you, your competitors and the cars race at 100% then looking for that 0.5% would be worth doing..in the real world it probably isn't noticeable.

[chrisguyw]

Most builders, (and all of the top ones)  of high end slot cars use non reduced diameter steel drill blank axles in sidewinder motor configurations that use motors with much much stronger magnets than the ones commonly used in 1/32 plastic cars.

Yes there is some magnetic attraction, but the frictional losses are very small, and quality steel drill blanks (non reduced) offer many benefits over the "reduced" axles from the plastic car manufacturers, as well as the various aluminum, carbon, and titanium axles to be found.

Cheers
Chris Walker

[BAracer]

It's a drill blank that's in there at the moment, and it will be staying in there now...

Thanks all.

[Kevan]

It's a drill blank that's in there at the moment, and it will be staying in there now...

Thanks all.

It's 100% more important the axle is straight and parallel...not all drill blanks are either of those.

[Brumos RSR]

I would use an actual axle made from your choice material of those mentioned above and based on the rules of your series regarding bushings and bearings.  I’ve used all 3 in proxies with success but, I also build them as race cars knowing that parts are going to be replaced when the car returns home.  None have been damaged or bent in proxies but I’m also racing non mag so I’m assuming less stress due to less motor rpm and downforce.  

If you choose to use carbon fiber, you must use bushings AND you must pay strict attention to how the grub screws bite into the carbon. Too much in any of the 3 places meaning wheel mounting or gear mounting can create a wobble when done improperly.  You will need bearings for this as bushing will generate wear.  For testing, I have run a Carrera Porsche 917 in a modified magnet class for 32 weekends for 672 minutes without issues this way.

[BAracer]

It's a drill blank that's in there at the moment, and it will be staying in there now...

Thanks all.

It's 100% more important the axle is straight and parallel...not all drill blanks are either of those.

I get mine from ABslotsport. They look and feel the part to me.

[BAracer]

Brumos, the only spare axle in my box is the titanium one. I'll find a use for it somewhere.

I've not read a happy story about anyone who has used a carbon fibre rear axle.

[chrisguyw]

I've not read a happy story about anyone who has used a carbon fibre rear axle.

That is because there are not any .

Cheers
Chris Walker