[chrisguyw]

Jeremy, 

I would make a guess that Chris's porn-box of gears is a retail box from which parts are for sale, maybe at a shop or a club.
C'mon Chris, fess up!

The parts are all mine, I use them on my own builds ........while I do send some bits and pieces to folks looking for them, I do not sell parts.

I do have some relationships with a few manufacturers, so, I do sometimes get a few bits to test, or some at reduced cost. When I do find a quality  part that I like (eg. 65/70 rockwell drill blank axles ) I buy lots,....as,... I know that I will use them, I am never sure how long anything remains available, and I appreciate the the quality/performance. 

The parts in boxes are all in as new shape...I do not keep faulty or worn parts...they go in the bin.

Cheers
Chris Walker

PS the place is a mess,.....With "social distancing", I have been spending a ton of time finishing up projects.











The box of gears shown in my prior post is the second box down on the left...........I do have another one in here somewhere. 

[dvd3500]

That has to be the worst workshop I have ever seen...
Because it's so clean and tidy!
:-)
Where's the fun in that?! :-D

[BAracer]

So the Scaleauto RT4 motor pod places the motor at 15 degrees to the axle rather than the traditional 25 degrees.

What gear strategy should one follow in this situation, as I am struggling to find conical pinions (although I think I saw some somewhere once...) or any 15 degree anglewinder gears?

Cheers

[chrisguyw]

There is absolutely zero need (or advantage)  to use bevelled pinions or angled spurs in an anglewinder set up.......straight cut gears are completely fine, and used far more than "angled" gears.

If you look, you will see that most high end cars (Eurosport/ISRA/Wing/BSCRA etc.) use straight cut gears in anglewinder configurations, and have for years. These cars put far greater loads on the gears than anything you run.

The shallowish angle of your pod (12 degrees) coupled with the narrow spur face width,  and the tooth depth of .5 module gears, allows the spur to engage completely with the pinion.....even if significantly too much lash is present......so there is zero need/benefit to use anything other that straight cut gears in your cars.
Straight cut gears can also be used "hub in/hub out", and obviously in sidewinder set -ups, so while inconsequential, they are more versatile, if that is relevant to you.

Like all gearing, proper set-up ( lash) is critical, and on an anglewinder is is vital the spur does not move laterally on the axle throughout the race..this will either tighten or loosen the mesh/lash, depending on which way the spur is allowed to move.......neither is the hot tip for fast laps, worse, it can lead to a trackside repair.

Cheers
Chris Walker

[BAracer]

Lash...is this 'backlash', i.e. the play between the two gears?

[chrisguyw]

Lash...is this 'backlash', i.e. the play between the two gears?

One and the same !!

Cheers
Chris Walker

[BAracer]

Thanks. 

I am going to do some homework on gear pitch, gear module... in fact I'm going to re-read the whole thread again now that I know what a didn't know the first time I read it.

And then, as advised by Mr Tamar, I will read it again.

[BAracer]

The dirty fix, I like that term. But I think you are confusing the outside diameter of the gear with the pitch circle diameter.
I believe the basis of this is changing the pitch circle diameter, to keep the effective pitch of the pinion as a differing circle diameter as close to the 0.5 modulus mid point as possible.
If for instance I swapped a Slot.it 6.5mm 10 tooth sidewinder pinion for a 12 tooth, the contact point of the 12 tooth, would be further out from the centre of the motor shaft, and the pitch wouldn't change by x 12 ÷10. 

Have a look at the different tooth shapes here, and how you might expect the two pinions to contact at a different pitch circle diameter point with a straight toothed spur gear

 

  

So the "pitch" or modulus value doesn't change as much as we would assume it does.



Does that all, those both make sense?

Loco

Re-reading the thread, this item caught my eye again... I'm struggling to see how the profile of the teeth will effect the pitch of the gear. 

Are you suggesting that the 'virtual' diameter of the 10t gear is smaller than the actual diameter because the other gear will mesh with it at the fatter lower part of the tooth rather than towards the outer tip?

[BAracer]

And a couple more gearing queries: -

1. Is there any performance benefit in using 'removable' pinions rather than friction fit ones? Is it just easier to use them if you are changing pinion sizes on a regular basis?

[BAracer]

...and are there any special circumstances where benefit can be gained by picking a particular pinion material (e.g. plastic or brass) or gear material (e.g. plastic/aluminium/ergal...)?