Armature Shaft Wear

[Lightning]

I have been experiencing problems with the armature shafts wearing on the pinion end. I have checked and it is the shaft and not the bushing. This has happened to 3 seperate ProSlot arms in the past few months. I feel it must be something I am doing that creates this wear.

I use a cutoff disc on my Dremel tool to shorten the shafts. Then soldier the pinion using a 40 watt iron. I oil the bushings every 5-15 minutes using Glidex. I have the pinion close to the bushing and the spur gear close to the axle bushing to reduce the leverage force on the bushing.

My thoughts are that maybe in cutting off the shaft it is getting hot and loosing its temper. Or since the pinion is close to the bushing the oil might not be getting down to it as good as it should (there is at least 1/32 clearance).

As a final note my Parma 502s with pressed on pinions do not have this problem. I treat and oil them the same way.

Any ideas????

[mazur50]

What i think it might be is that pro slot has two kinds of shafts. Brill blank and not brill blank. a no drill blank where very fast. may be one or two races. and i drill blank will last for a long time.

[Lightning]

Thanks for the response. How do I know the difference between these two shafts?

[mazur50]

I think that there maybe be a D ingraved in the arm and the drill blank will be circled on the tag when you buy it in the wraper

[jake]

mazur50
do you know if there's any way to ID the drill-blank arms in a complete ProSlot motor? (S16D) I'm seeing wear on the can end and it isn't that old.
Thanks for any response
Regards/jj

[ET37]

it's pretty simple....if the bushing isn't worn out, and the arm is, then it isn't a drill blank arm unfortunately!!! Boxstock racers have been experiencing this problem for years now, but any newer arms have been made with "chrome" plated shafts so i'm told and i haven't worn out an arm since the introduction of these arms!

basically if it's worn or is sloppy in the setup, then it's not a drill blank or similar.

[Monty @ B.O.W.]

ProSlot currently offer two different shafts, the REAMER blank, which is the one everybody refers to as a drill blank, and the tool steel chrome plated shaft. The plated shaft is used on most of the arms, at popular prices. The other is a higher priced option for Gr.12, and standard on G27/7.

Worn shafts were getting to be a big problem almost two years ago. After many gripes and some bad press, the chrome plating was introduced and it solved the problem for MOST racers. Lightning, leave the Glidex in the box, and use something with higher viscosity, like Champion Turbo Lube. Also, oil EVERY race heat, as in every 3 minutes - even more in practice! Solder your bushings in quickly, to avoid leaving fried oil in the porous metal, and reoil with the TurboLube while the bushing is still hot, as it will absorb some of it.

Finally, do not be afraid to oil the endbell bushing too! If you DO get oil on the comm, its easily removed with motor spray or lighter fluid (naptha). However, if you keep the drops small, you can also oil every heat.

[cheater]

Monty is correct about NOT using Glidex with bushings. I had the same shaft wear problems using Glidex with multiple brands of bushings and completely solved my shaft wear problems by going to a Mobil 1 OW30 / Tufoil mixture. I am virtually certain that your shaft wear problems will disappear if you go to another synthetic oil.

Rudy G. and I swapped a few emails about this problem and he indicated that the Gildex is best used with bearings. I also note that Slick 7 now sells Glidex II with more viscosity, but after ruining $100s in arms, I have not tried it.

I don't want anyone reading this post to think that I have any bad feelings about Slick 7. Rudy's product line is the best in the industry for the serious slot racer. And I'm betting the Glidex works fine with bearings; it just doesn't work with bushings in my experience.