AmoebaCowboy

I've now broken 3 stub axles on my Monsoon, one front universal and 2 rear stubs. All 3 times they sheared off at the hub retainer pin. I'm wondering if this is a known issue with the Monsoons and if Redcat is doing something about getting a better quality supplier for these. Idoubt it was just a bad batch since the stubs were both a new & and old set so the chanes of me getting replacements from the same bad manufatured batch are slim.

Does anyone have a recommendation for a hop-up replacement? It looks like the Losi 8ight rear universals will drop in as the length is the same though the Losi rear hubs carriers are a slightly smaller hingepin width so I'd have to put in about 1/4" more of spacers. Any other brand parts that would be a direct replacement? I'm hesitant to order yet another Redcat stub....

AllAboutFunHobbies

Can't think of any off hand. Never had anyone come back or buy the stub axles for the monsoon. Matter of fact I think we still have the same one bag of them from when they first came out. Don't sell very much of the big stuff.

AmoebaCowboy

Yeah, it's not a part I expected to fail and in the manner it did. But 3 of them have failed in the 6 months I've owned the Monsoon which is why I was hoping to find a different brand replacement.

Redcat, any help? Is there a universal hop-up option for the rear bones/stub axle? I'm hesitant to order yet *another* set of stub axles if the quality is the same....

Redcat Nick

You can upgrade to the universals if you want but out drives are a wear part. Which Monsoon do you have?

AmoebaCowboy

Thanks for the reply Nick. Ihave the XP, not the XTR. I understand the stubs are a wear part but we're talking less than 4 tanks of use on the sheared stub

I picked up a complete front-end assembly a while back but the universals for the front don't *quite* fit as a replacement for the dogbones/stub in the rear. There's less than a mm difference or so, the universal stub end retainer nut rubs against the bearings and doesn't turn smoothly with no resistance like they do in the front. Are the rear universals a different length or are the bearings in the rear carrier a different horizontal width? I'll try swapping the bearings from the extra front-end Ihave and see if that makes a difference.

AmoebaCowboy

Much as I hate to bump a dusty thread of mine....

Since my last post on this issue Ihadn't run the Monsoon at all. I finally got around to replacing the broken rear stub with a front universal (the rubbing issue was user error, they work just fine if you actually make sure the bearings are fully seated in the hub carrier first *grin*). I took it out to the track this weekend to play around with after my buggy a-main was done. It went a total of 20 feet around the first berm and over a small lip drop (<1ft.) and when it landed the rear wheel went flying. Guess what? Yeah, another sheared stub axle. On a brand new never before used part. At the same hub pin location. We're talking *maybe* going 10mph and landing completely flat & straight off a 1' drop on a new part with a whopping total of 5 *seconds* of run time on it. This "wear part" didn't even have the chance to get dirt on it for chrissakes.

That's 4 stub axles sheared off at the same point in less than a gallon of run time, 2 of them under very light running since Iwas babying it like you do for a little while after replacing a part. Redcat, here's a big difference between a wear part and a faulty part.

I've previously been a proponent of yours and have defended or talked up your products to friends or on forums. Unfortunately I don't know if Ican do that anymore.

jigawatt

can you provide a top view and side view of it installed in your monsoon? I ask so I can see what angle you have your monsoon set at. If you could, please include photos of how the dogbones sit with the suspension fully extended too. Basically I'm curious to how much slack your universals have.

stub axle??? Drive cup/axle I'm guessing? or is that the term they use?

This is what I assume you are talking about:

AmoebaCowboy

Not the drive cups at the gearbox/diffs but at the other end at the hub carrier, though the parts are similar. Redcat part#81082. The shear point is at the hub retainer pin, not the U-slot for the dogbones. Shock travel would have nothing to do with it in this case (dogbones aren't binding or allowing excessive travel in drive cup slot but good thought on your part).

Bear in mind that this is the universal that just snapped. The previous 3 were the regular stub axles (part #81082). All 4 of them failed at the exact same spot.

jigawatt

ok so my next question, was the metal hot when you picked up the parts after it broke? are the bearings fine?

AmoebaCowboy

Hrm, just noticed this via google search: http://www.xenonproject.com/rc-truck...cs-p-3238.html

Upgraded Redcat rear stub axles? Redcat Nick or other Redcat dudes, is this the same as your #81082 part or is this in fact an upgraded hop-up?

AmoebaCowboy

Not hot (no heat fatigue) and bearings are all perfect, no gritty/grinding sound or feel, and are seated with no slop or give in the hub carrier. I did do a lot of due diligence on this issue after the second time one sheared on me. In this last case, there wasn't even time for any possible heat to build up even if the bearings had been full of rocks & locktite

jigawatt

thats definitely no bueno!

jpilkinton

I wonder if the stubs were heat treated too long. That would cause them to be brittle like that.
Also, does the tightening of the wheels cause tension on that area?

AmoebaCowboy

It's possible on the heat treatment during manufacture. As for the wheel tightening causing tension, it does (for any car using this stub axle design which is very common). However, the tension is directional to the outside of the stub along the length of the cylinder and not sideways across the width where it's shearing.

Either way it would be nice to hear a response from Redcat on this.