Mod1 or 32 pitch? This gear is like COMPLETELY eaten.

[JeffEmbracedDC]

Okay, so as some of you may know, I have a brushless Ofna Hyper 7. I didn't know if this topic should go in brushless, or nitro, or what, so I just put it in here. Anyway...

I purchased a mod1 carbon steel gear from monster RC for my 540C8XL motor to put on my Hyper 7 with stock main drive gear. Everywhere I had heard that these aren't truely 32 pitch, they're mod1 and if you were to try a 32 pitch gear it would get eaten up immediately. So anyway, after a few runs my pinion gear is not just worn - it's like COMPLETELY gone. Like I seriously don't know where part of it went. There is a huge huge groove right down teh center of my pinion where the spur gear sits. So basically I am wondering - WHY? Is my gear actually a 32 pitch? is there something wrong with the carbon steel? I don't know what's up and I thought someone with more knowlege might be able to help. My gear mesh was set very well so It has nothing to do with that. Anyone have any ideas? Thanks.

-J

[JeffEmbracedDC]

Okay, so here's a photo.

http://www.embraced-dc.com/temp/RCStuff/Hyper7Conversion/IMG_0049.JPG

This is after 2 normal runs, mind you.

-J

[rhcsavage21]

holy wow that is crazy. weird thing is i dont se the slightest damage to the spur gear.

i'm going to guess here that the gear was not at all hardened. try getting another one and see what happenes.

[awnelson]

I would be concerned about your setup for the motor to center gear. Under load the plate may move just enough to allow the pinion to ride up the spur teeth. It doesn't look like the spur teeth meshed completely with the pinion. If there were a way to lock down movement to the back of the motor, you might see a change.

I would think that M 1.0 wouldn't mesh close enough with 32 P and you would know they weren't the same. It's also possible that you need to keep lube on the pinion or get a teflon coating put on it.

[JeffEmbracedDC]

Hmm. Well, I haven't ever dealt with 32p or mod1, so I'm not familiar with how it SHOULD mesh. It seemed a bit weird to me, but I figured that's just how it was. It could have been slightly tighter, but I know it wasn't loose enough to cause that issue. The motor mount is absolutely rock solid so I'm pretty positive that they weren't separating under heavy load. I am guessing that the carbon steel is not meant to be used with a steel spur gear and it got all chewed up due it not being hardened like RHCSavage mentioned. I'm going to call Ofna and make sure that this is a mod1 gear rather than a 32p.. then I'll call up RC-Monster (where I ordered the pinion from )and ask if the carbon syteel is meant to be used with steel spur gears or what. I think I should be able to settle this with those two calls. Thanks for your input. I am starting to feel that this gear just might not be meant for use against steel gears. I think it was Demon-TC3 who had mentioned that same thing previously. Thanks again, guys.

-J

[ElectricThunder]

Your spur is steel. That's your first problem...:D Apparently the carbon steel was definitely not hardened or something. Looks like it just got eaten up as if it were aluminum or something.

So I have two suggestions:

1) Make sure whatever pinion you get is hardened and is one helluva beast

AND/OR

2) See if you can find a plastic spur for your center diff (kyosho perhaps?).

[JeffEmbracedDC]

Thanks :) I might try both. I'd like to get a plastic spur because the gears are pretty loud. Of course it wouldn't matter if you were running a nitro engine, but it's really loud for an electric vehicle. I'm gonna try to get a nice hard pinion and also try to pick up a few nice plastic spurs if I can find them. Thanks! Good idea. I didn't know that nitro cars used plastic spurs sometime. Come to think of it, I think when I had mt GTs they had plastic spurs. Anyway, thanks!

-J

[awnelson]

Ofna makes plastic spur gears for the center diff. If both materials were similar, the lower hardness will always lose. If they are different they can usually be self lubricating. Since you don't have a slipper in the assembly, the plastic one may tear teeth under shock load (off jumps, hard accel on mixed ground) so keep that in mind and never give up. Just keep trying; you will find something that works sooner or later.

[JeffEmbracedDC]

Aye, thanks. Yeah good point about the slipper.

-J

[ElectricThunder]

Thanks :) I might try both. I'd like to get a plastic spur because the gears are pretty loud. Of course it wouldn't matter if you were running a nitro engine, but it's really loud for an electric vehicle. I'm gonna try to get a nice hard pinion and also try to pick up a few nice plastic spurs if I can find them. Thanks! Good idea. I didn't know that nitro cars used plastic spurs sometime. Come to think of it, I think when I had mt GTs they had plastic spurs. Anyway, thanks!

-J
No problem. It's probably cheaper to replace a cheapy plastic spur than a more expensive mod1 pinion (I've seen those suckers go for around 13 bucks! AH!).

If you're also in need of 5mm bore mod1 pinions for a little cheaper (something like 7-8 bucks), tower has some (I have no idea if they're hardened or not, and what they're made of; if you go with a plastic spur though, they should be dandy). If you want, I can see if I can dig them up.

A slipper would be a good idea too...but probably difficult to implement. I think, from what I remember, most people running 1/8 conversions that aren't running slippers have had no troubles stripping stuff in relation to jumps and what not. I've just observed pics they've posted of their setups though, and haven't read any complaints of said problem.

[JeffEmbracedDC]

I called Ofna and they said they don't offer a plastic spur option.. I also looked around online for like 15 minutes and didn't find anything anywhere.

The pinion I got was called "carbon steel". I have no idea if this carbon steel was meant to be used with steel spurs or not, so I emailed both RC-Monster and Starluck RC both of which deal with these pinions a lot so hopefully one of them will know if I chose the wrong pinion, or what. I'm pretty sure I won't be able to find a plastic spur for my spider diff, but even if I do I think I'd rather stick with steel seeing as how I have no slipper. If I went with plastic I think they would get chewed up really bad really fast. This buggy goes like a bat out of hell and jumps like crazy. I couldn't believe how high I was getting with such a short accelleration area. It was insane. Once I get this fixed up I'll be taking some more video. It's pretty awesome. It accelerates like crazy and I love it. So anyway, I'm waiting to hear back from starluck and monster.

-J

[awnelson]

How much do you think you have tied up in the buggy now? I am thinking of converting a REVO but don't want the big dollars flying out the window unexpectedly.

[pinolelst]

Plastic Kyosho spur might fit.I was warned about steel spurs in electric buggy conversions.Buggies are typically mod 1 gears btw...
I run steel spurs in my LST and tini pinions and so far so good but it has mechanical brakes.I wonder if the motor braking is the cause of the failed pinion in your case?? I think the plastic spurs have a little give to them as well and less of a chance of becoming a pinion saw blade :p .

pinolelst

[JeffEmbracedDC]

Well, I had the esc, servo, batteries, and misc hardware.. so I purchased:

rolling chassis for $140,
motor was $85 I think
battery straps (which I don't recommend. I recommend using the 3Racing straps instead of GorillaMaxx ones)
pinion was I think like $13
motor mount (from e-maxx) was something like $8
Motor mount brace (actually an aluminum servo mount) was like $7
40mm fan for ESC was like $12 from radio shack

I already had the esc which is about $125
batteries - well you know about those I'm sure

I think that's about it. I'm not sure if you saw, but I put some info up on the project - www.embraced-dc.com/Hyper7Conversion The video kind of sucks and I'll get a better one after I get a new pinion. It goes really well and I'm super happy with it so far. I just hope that the car can sand up to all of the weight (batteries and heavy motor). Well see in time, I'm sure.

-J