SlotForum banner
21 - 40 of 45 Posts

· Registered
Joined
·
2,085 Posts
Spot on Mr Croker, thats what Im saying. A 0.5g weight loss in a car weighing about 85g, thats about a 0.6% weight loss. In a mag car thats probably noticable. In a non mag car it would be marginal to pick the difference.

Im using a hollow axle as an example and saying that if it is 1g lighter than a standard axle you would achieve the same inertia improvement by removing 0.003g of mass from the tyres. Thats 3 milligrams. So lets keep the solid axle in place and remove 0.003g from the weight of the tyres and I would get the same benefit. I defy anyone to say they could notice that the car felt "faster" and spooled up quicker because it was now 0.003g lighter.

The gain in reduced inertia between a brass pinion and a plastic pinion would be very small. Brass pinion is 0.05g?? So 1/5 of that is 0.01g We have a weight saving of 0.04g. Like I said im happy to be proven wrong but show me the data. Send a packet of pinions into this forum so that one of the moderators can do a back to back test. Happy to eat humble pie.

If anything Id say there was more gains to be had by reducing the friction between pinion and spur if the gear profiles were done well.

cheers
rick1776
 

· Slot King
Joined
·
4,687 Posts
QUOTE (rick1776 @ 5 Sep 2012, 00:12) <{POST_SNAPBACK}>Set up a drag run. Measure the elasped time with a brass pinion. Replace the brass with a plastic pinion. But make sure to add the weight difference so that the car's overall weight does not change. Repeat the drag race run. Now you will be testing the effect of any reduction in inertia. Do the run 10 times and take the average. Repeat with the plastic pinion. I suspect that the variation between any two runs will probably be greater than any "measurable" gain. Once again happy to be proven wrong, but pleased show me the data.

I would want to see a double blind test, to remove any trace of subjective judgment on the part of the driver.
I think in some respect we are both missing the point, the idea is to get the customer to think it makes a difference, the actual difference is less important.

QUOTE (stoner @ 5 Sep 2012, 07:34) <{POST_SNAPBACK}>we,re really arguing about top racers in world finals. if it gives you 1inch more per lap its a better product. john

John, no we are not, we are talking about cheap plastic pinions used to run at home or at club level.
If the gain is 1mm per lap, then you have wasted your money, and as rick1776 and I have hinted, there are many many other factors (including some unexpected ones) which will make a more noticeable difference and cost nothing.
In any case what works at top level does not always transfer lower down (like a shopping trolley with F1 tyres for example).
For me the irony of these transmission "improvements", is that most of these cars still rely on the motor shaft rubbing on the side of the contrate to locate the rear axle.

Joel
 

· Registered
Joined
·
3,558 Posts
that was just an extreme situation i wrote to to get the point across and your not wasting your money, if you have to buy gears. their probably a lot cheaper than their metal counterparts. Theirs speed rings for less contact and friction and teflon washers with the lowest coeficient of friction known to man, and they dont have to be lubricated either. the gear and pinion if its adjusted right its the perfect solution, because you dont have to use any stoppers. in fact i think MB slot should send me a pair for testing seeing as i seem to be standing their corner in this debate. john
 

· Nobby Berkshire
Joined
·
1,987 Posts
The important thing is to try something new first before generating a bunch of reasons to reject it. Theories are useful but only if you don't fall into the trap of replacing reality with them.

It's also interesting to see people rejecting plastic gears based on experience from years ago. I've never had to replace a plastic or nylon pinion in 6 years apart from the useless new grey Fly ones, and that wasn't because they are plastic but because they are badly designed.

And many plastic geared cars beat metal equivalents. There's nothing advantageous in 'metal' at all.
 

· Slot King
Joined
·
4,687 Posts
QUOTE (Screwneck @ 5 Sep 2012, 19:52) <{POST_SNAPBACK}>It's also interesting to see people rejecting plastic gears based on experience from years ago.
I know, shocking isn't it!
But I had to go back a long way to find a pinion as poorly designed as the ones shown here.

QUOTE (Screwneck @ 5 Sep 2012, 19:52) <{POST_SNAPBACK}>I've never had to replace a plastic or nylon pinion in 6 years apart from the useless new grey Fly ones, and that wasn't because they are plastic but because they are badly designed.
I am glad you agree with me, nothing wrong at all with a properly designed plastic pinion (within reason), I too have had good experience with Ninco, Fly (in the early Vipers), and Scalex plastic pinions.
But they all share one thing in common: A reinforcing ring at one end to stop them splitting. I am much less convinced by what I am seeing here.

Joel
 

· Nobby Berkshire
Joined
·
1,987 Posts
Joel, I'm not agreeing with you. But I do see your point


You need to try something before you reject it. Whether it splits or not depends on the type of plastic it's made from, its density, and lots of other things.

If I used your logic, if I bought a baguette that had a dead mouse in it, I'd never buy another baguette on the basis that I'd assume all baguettes had a dead mouse in them.
 

· Slot King
Joined
·
4,687 Posts
But you certainly wouldn't buy another from the same bakery, or in this case of the same design.

The difference is that Ninco and the others have designed a pinion which they know will be reliable, surely they would have used the same plastic as MBslot and saved themselves the bother?

I am not at all convinced that those pininos are not just bog standard stuff available form many factories in China (in fact, I have found similar ones myself).

Joel

PS: And we have not discussed the price yet (the Chinese pricing is rather interesting).
PPS: The French would much rather buy a bas*ard than a baguette any day (Anglo French joke about bread)
 

· Jim Moyes
Joined
·
6,528 Posts
Joel,

I wouldn't hold up Ninco plastic pinions as a standard for excellence. I've had and seen many split ones even though they have a collar. And the awful Fly plastic pinions that Screwneck mentions also have a collar. I'm of the opinion that the type of plastic used is a big factor and possibly even the colour of the plastic. Back in the height of the Scalextric "split pinion" era some C7 Minis came with a grey pinion instead of white - I've yet to see one of those fail!
 

· Registered
Joined
·
2,085 Posts
QUOTE (Mr Croker @ 7 Sep 2012, 08:24) <{POST_SNAPBACK}>So you do not get the irony in the fact lighter makes it quicker but apparently not when it's a pinion. Hmm....

In all my years of club racing i have yet to hear anyone say, "....and when my wing mirror snapped of in that last crash, I couldnt believe how the lap times just tumbled". We are after all talking of a weigth saving of 0.04g at best.

Like I said Im happy to eat humble pie with blind back to back tests and defy anyone to pick which car has the plastic pinion fitted.

cheers
rick1776
 

· Registered
Joined
·
1,873 Posts
Gentleman as a user of metal pinions & contrates from their introduction, before that there were plastic pinions e.t.c and they were ok coming back into the sport i note there are plastic pinions still in use i expect better than the original and as far as the weight thing goes with half a ton of lead or no lead at all in a car the weight of the pinions is let's face it laughable!!! , and i have never had a plastic pinion break perhaps i set my cars up so they mesh properly Keith.
 

· Tony
Joined
·
2,822 Posts
A couple of important things to consider when picking a metal or plastic pinion are the motor torque and how hot it gets. I don't think a plastic pinion would last long on a Wasp,Super 16D, Falcon 7 or Group 12. I have suffered the Proslot split pinion but that's just down to poor quality and not being plastic
 

· Registered
Joined
·
3,750 Posts
Could I ask if anybody knows how well these mesh and how well they last?

How well the gears mesh can make quite a difference to how well the cars go.
Probably a larger difference than the change in inertia due to a lighter pinion.
 

· Registered
Joined
·
2,085 Posts
QUOTE (Bigtone @ 7 Sep 2012, 15:43) <{POST_SNAPBACK}>A couple of important things to consider when picking a metal or plastic pinion are the motor torque and how hot it gets. I don't think a plastic pinion would last long on a Wasp,Super 16D, Falcon 7 or Group 12. I have suffered the Proslot split pinion but that's just down to poor quality and not being plastic

I did use a plastic pinion in my 1/24 racing with a motor having about 220g.cm torque (came with the motor). It did last the season (10 races) and then spun after the race when I was practicing/tuning after the last round. Got lucky. A friend of mine who I was neck and neck with in the championship spun his pinion in round 7, cost him the championship. I usually use a metal pinion and plastic spur with metal boss and grub screw. It works well. Plastic pinion and plastic spur with no grub screw.....Hmmm.

cheers
rick1776
 

· Registered
Joined
·
1,873 Posts
Rick1776 & 300sl i have never used plastic pinions in 1/24th in my Parma racing days we always soldered the pinion to the shaft then set the gear train up with a very light compound to mesh the gears in making sure you stripped the gear down afterwards to get any residue cleaned off always worked perfectly, i have only used plastic pinions on lower powered 1/32 slot cars up to 29K and mesh them in with a bit of toothpaste again cleaning the residue of and it still seems to work like it did 40 years ago mind you it does not make them any whiter just smell of peppermint, i have found the plastic pinions and gears of today pretty well made ( i don't use scalex ) and the toothpaste and a Rizla gets them perfect, i have yet to experiance slipping, the only problem i have had is in the modern contrate with the very small grub screws once you drop them you can never find them again and these contrates i have experianced slipping and to get them to grip have stripped a few also applies to some modern wheels, Keith.
 

· Tony
Joined
·
2,822 Posts
Peter get yourself a stick with a magnet on it, it,s amazing how it seems to pick up things you can't see. I don't like those little M2 grub screws Slot.It use, always going missing. Why don't they use M3 like others
 
21 - 40 of 45 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top