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View Full Version : DAMAGE REPORT!!!! RORTY CAR



dune
03-28-2007, 10:25 PM
Just finished seting up the suspension and decided to take it for test drive #2. Needed a navigator so I asked my daughter to hop in. She was jazzed to say the least. The field was still quite wet but we said lets go for it. after about the 4th lap around we were in a straight section just topping out second gear and "Wack-Clack-Clunk!!!. I immediately hit the brakes as I felt the power drop off. I thought initialy, I threw the chain and as I was cllimbing out, I was contemplating what kind of damage to expect. To my surprise, The left rear axle had sheared completely off flush with the outboard side of the bearing carrier between the hub. I was completely beside myself. [smilie=banghead.gif] *Killed an axle in just about 10 laps around my field and no jumping!
[smilie=big_explode.gif]
Got the tractor and hoisted/hauled it back to the pits. *Damage is as follows:

Type 1 w/ 930 flange stub axle *toast!
Tatum Brake caliper mount * * * toast!
Tatum brake caliper * * * * * * * * toast!
Tatum brake rotor *completely *toast!
[smilie=banghead.gif]

All bearings are free and spin fine. Bearing carrier-fine, main hub-fine, drive axles fine and rotate freely, cv's are fine

What caused this to happen? A Bad ass powerful motor?, Too much rotating mass?, Or what I suspect a piece of chit stub axle!

dune
03-28-2007, 10:30 PM
More damage photos:

please give opinion of failure.

masterfabr
03-28-2007, 10:39 PM
Chitty chitty bang bang stub material.Buy better stubs. [smilie=biggrin.gif]

yoshi
03-28-2007, 10:41 PM
Man that sucks, I have always feared a stub breaking like that when I jump, there is so much load pushing on the spot the hub exits the bearing carrier. *I'm doing something different with mine, pretty cool setup but complex. *I'd say you got some cheap stubs since I haven't really heard of that happening very often...

masterfabr
03-28-2007, 10:41 PM
BTW, sorry you had a problem. The car looks great.

dune
03-28-2007, 10:42 PM
Sad thing is I thought I had good stubs. I ordered and waited on them for a month. Not sure of the exact brand or mfg. They are not tatum though.

masterfabr
03-28-2007, 10:46 PM
Yoshi,You coming to LS tomorrow or friday? I'll be there about 2 tomorrow.Sorry for the thread jack,dune.

masterfabr
03-28-2007, 10:48 PM
Oh well,he's offline now anyway.Probably needs his beauty sleep! [smilie=biggrin.gif]

dune
03-28-2007, 10:49 PM
no prob, Can anyone tell from the close up photo's if the axles had a flaw in them? there is a spot that looks suspicious.

masterfabr
03-28-2007, 10:51 PM
I don't think it was a flaw unless bad material selection is a flaw. [smilie=closedeyes.gif] Bad as I hate to say it (I'm not really a fan of them) I'd probably buy some Gear-One stubs.

dune
03-28-2007, 10:52 PM
These are not Tatum Not sure of the brand. But I'll check gear one

masterfabr
03-28-2007, 10:55 PM
The gear -ones are quality pieces and shouldn't have that crap happen ever.

dune
03-28-2007, 10:58 PM
Sounds great I give 'em a try. Thanks

plkracer
03-28-2007, 11:43 PM
It must have had a lot of stress there. Was the hub tight? I'm glad I'm running with solid hubs, and the axle will come out without dropping the wheel. Never thought of it breaking during a jump.

plkracer
03-28-2007, 11:47 PM
I don't think that those axles are the best. We've had hardened axles twist so that they were a whole spline or more off, but they didn't break. They wouldn't crack like those did either. I can see the splines seperating. It looks like they were case hardened, not hardened all the way through.

dune
03-28-2007, 11:58 PM
It's crazy how easily this one broke. No jumping, just semi aggresive driving straight and level and bam! The hub was still very tight to the wheel no slop at all this has to just be a piece of crap stub.


Surprised Rorty hasn't chimed in yet....

Rorty
03-29-2007, 12:27 AM
Sorry to hear of the failure, especially after so little use. I suspect they are pattern axles, possibly from Taiwan or somewhere else where stuff is made from low grade recycled "steel".

I think you have your answer though - buy some quality parts and you should be under way again. Incidentally, I have heard bad reports about Gear One axles recently which may or may not include their stub axles. Just something to bear in mind when you're speaking to them or ordering replacements.

Rorty
03-29-2007, 12:29 AM
It's crazy how easily this one broke. No jumping, just semi aggresive driving straight and level and bam! The hub was still very tight to the wheel no slop at all this has to just be a piece of crap stub.


Surprised Rorty hasn't chimed in yet....

Hah! We both posted simultaeneously. I've been busy on another puter most of the day.

boilermaker
03-29-2007, 12:40 AM
I have seen axle shaft's that had a flaw that broke after years of abuse and have had axles twist almost a quater turn. I don't beleive your axle had a flaw, i beleive axle was brittle. Wasn't heat treated right.

boostick4
03-29-2007, 01:14 AM
dune,
* * Can you take a large close-up photo (macro would be nice....you know the little flower button on your camera) of the end of the shaft? There does seem to be a spot on that one picture that is rather od but its hard to tell. Also, do you know what type of material it is made from and if there was any heat treatment done? That really sucks man hopfully the next round will last.

Woody

Bugpac
03-29-2007, 04:31 AM
dune were did the stubs come from? maybe someone has a rockwell hardness tester you can give them a check.....

K-fab
03-29-2007, 06:50 AM
I'm with boo on this. *

Can you get a close up of both ends of the shaft - similar to the third picture you posted. *

Notice the little dark spot at 9 o'clock? *That was the last section to let go. *It probably cracked at or around 3 o'clock and then proceeded to twist itself off. *Take some pix of the axle splines of the 3 o'clock area too.

It almost looks like there is no hardening. *The shaft should be, at minimum case hardened. *You don't want it hardened all the way through, as that makes the part brittle. *Keeping a soft center allows for shock loading to be absorbed. *It's weird the way things like that work.

Are the stubs your using micro stubs or are they a regular length stub?

Either way, I'll go along with the other guys and say it's time to call Gear One or McKenzies and get a brand name piece. *Gear One has had some issues, but from what I hear, it's not the material, it's that their splines are a tad on the loose side and eventually they'll loosen things up. *

Give Desert Dog a call and ask Jay who's stubs he uses - I'm 90% sure it's Gear One - and he's not had any failures on his cars.

masterfabr
03-29-2007, 07:01 AM
Contrary to popular belief/misconception that little spot in the middle is not a problem or cause.Just a result.k-fab is correct that the failure began across from it but there is no "smearing" of metal that I can see so that indicates that the part just catastrophically failed instead of propagating from a defect.It looks identical to a failed valve stem that has broken from flex,not a flaw in materials.Just buy some quality stubs and forget it.fabr

dune
03-29-2007, 07:06 AM
Thanks for all the feedback. I'm going to call several axle distributors. I do have a nice macro lens for the 20D and I'll try and post some reall good close up's for all to examine. I'm glad this happened now rather than next week out on the dunes. Would have sucked being stranded. *

On the plus side the rorty car IMO handles great and felt much better the second time out once the suspension was ajusted. I was able to get into 4th gear briefley and I believe me this package will put you back in the seat! The tranny and gearbox seem to be working out great. Getting very anxious to let this baby run flat out on the dunes.

Tripp

dune
03-29-2007, 07:34 AM
here are some close ups of boths pieces.

Have at them.....

masterfabr
03-29-2007, 08:11 AM
I could be wrong but I believe the failure began as a crack in the area of the blued spots and traveled towards the dimple of the inboard side in a radial pattern.As the crack got closer to the dimple the shaft was sufficiently weakened enough to be too weak for the torque and final failure occurred as a twisting motion causing the torn out dimple.

bikelomen
03-29-2007, 02:52 PM
HOLY CHIT BATMAN. Sorry to here about your car Dune. At least you had a tractor to haul it back. had to push mine up the street myself [smilie=ext_crutch.gif] Hope you get it ironed out before your trip

CBRhino
03-29-2007, 03:14 PM
I don't know much about buggy axles and stubs.....but I have been running Gorilla Axles on my CBR600 powered rhino......becuase they make axles that will fit stock Rhino suspension........I ran them without any issues with the CBR.....and will also be running them with my new 1000cc engine.......do you think it's your engine power that caused those to fail? *I'm just trying to figure out if I will have an issue with my axles if they aren't strong enough to handle the power of the SV1000........

bajatex
03-29-2007, 05:04 PM
Dune,

*I believe that Gear One has a huge stub axle that will fit into the type one carrier. *You just change your bearings. *It looks like you are using the type 1 size stub which is the smallest diameter compared to the bus stub or the monster stub from Gear One. *here is a link to the Gear One stuff. *I would just call them and tell them what set-up you have.
http://www.gear-one.com/Htmls/micro_stubs.html


Bajatex

plkracer
03-29-2007, 07:05 PM
There obviously was a crack or defect in the metal if it is blued inside like that. Those look to be case hardened.

Blade
03-29-2007, 07:23 PM
Yep that was cracked when it was heat treated.

K-fab
03-29-2007, 07:37 PM
I could be wrong but I believe the failure began as a crack in the area of the blued spots and traveled towards the dimple of the inboard side in a radial pattern.As the crack got closer to the dimple the shaft was sufficiently weakened enough to be too weak for the torque and final failure occurred as a twisting motion causing the torn out dimple.
I agree fully.
My pointing out the little dimple was to say that was the last part that was holding on - it's where the final twist of the metal was. *(which is what I believe you were saying I was saying anyhow, right??) * [smilie=blink.gif]

dune
03-29-2007, 08:46 PM
I went to Oregon motorsports and explained what happened to the Owner. He was very surprised to here that one failed like that and offered to replace it. Kris is pretty cool. He also asked how much I torked the nut down. That's when the bulb went off in my head. I asked how tight should they be? [smilie=ashamed.gif] *He said around 300lbs of tork. If this is correct it may have been completely my fault. [smilie=big_hang.gif] *Mine were only feel good rachet tight. then avanced or backed up enough to allign the cotter pin holes.

The stubs I have he claims, are the highest quality German mfg. Not china or japan. For what its worth. I'm new to all this type 1 stuff. I went ahead and got another one and still need a brake rotor to get rolling. I'll give them one more shot and tork them down as he specified.

We'll see.

I did research the gear one stuff and they look very promising. That will be my next stop if these don't work

Tripp

dune
03-29-2007, 08:51 PM
HOLY CHIT BATMAN. Sorry to here about your car Dune. At least you had a tractor to haul it back. had to push mine up the street myself [smilie=ext_crutch.gif] Hope you get it ironed out before your trip

Bike glad to here your head is still in the game!! [smilie=biggrin.gif] *Chit happens, I guess... Hoping I can get the rotor before next wed. We do have a pretty cool trip planned end of next week. *

Any progress or thoughts on your car?

boostick4
03-29-2007, 10:47 PM
Dune,
* * Sorry if I offended you with the macro comment I did not mean anything by it. Anyone that has a 20D should know their way around a camera. Hope you like yours....I love mine; itís a lot of camera for the money. [smilie=biggrin.gif] On to your axle. Did you find out what type of material it is yet? I hope you like my ms paint skills. The arrows show all the small cracks at the root of the splines that led to this failure. Once that outer "shell" is compromised its pretty much over. *[smilie=big_explode.gif] *While you have the car on jack stands take the hub off and clean the other stub really well and see it you can find any cracks starting on that one. If so I'd look some ware else for your axles. That little nub and the blue spots were definitely the last material to hang on. Was there any way that you could have hit the gas and brake at the same time? Hope you can find a solution that makes you happy. Good thing is no one got hurt. Oh one other thing, what is the major and minor diameters of those stubs? Good luck.

Woody

bdkw1
03-30-2007, 12:27 AM
He also asked how much I torked the nut down. That's when the bulb went off in my head. I asked how tight should they be? [smilie=ashamed.gif] *He said around 300lbs of tork. If this is correct it may have been completely my fault.

Torquing them down to 300#'s would have done little for this type of failure. The way the cracked and smeared (blue spots) tells me that they are crap material. Now if there were no twist marks and it was a clean shear I might partially belive it. Yes the nub was the last part to go. The blue areas are heat marks caused by friction as the 2 sides of the crack rubbed on each other. Looking at the grain, I don't think there was any heat treat involved in there manufacture. I've had old buggy's strip out a drum's and drive back to camp with the whole stub loose and never had one break like that.

K-fab
03-30-2007, 06:33 AM
Only 300#?

The micro stubs used in the Dez are torqued closer to 600# - requires a 5' long bar with one person hanging on the end of it while someone stands on the brakes.

Blade
03-30-2007, 09:53 AM
The blue color is most likely from cracks that were already present when the part was heated for forming or heat treating, the steel has to be exposed to air in order to change colors. When you heat steel it does not turn blue until it reaches 530-600 degrees F, I don't think that the part could have generated that much heat with the little movement that it had before it broke.

boilermaker
03-30-2007, 12:42 PM
I think you should have axle stubs Magnafluxed or Wetmagged to checked for crackes before useing those you have now. As far as the proper torque, it depends on the size of the nut and the material there made of, i would think 600# would be excessive. I'm sorry your haveing problems, i still think it's a case of improper heat treating or wrong material to use for axles to begain with.

dune
03-30-2007, 10:01 PM
OK. Got the car up and running again today. [smilie=biggrin.gif]. Installed a new stub, caliper mount and rotor. Put the car through some pretty intense driving. Lots of high speed passes over some pretty rough terrain and allot of high speed conering over rough terrain. Much more aggressive than prior. I wanted to try and break the SOB. But the Rorty car soaked up the bumps real nice and floated over everything. (Fingers are crossed). Was able to hit 4th briefly. This baby is going to be scarry fast when flat out! It is very very quick! with allot of gear range. Just about ready for the dunes
I do agree that the original stub had a flaw as mentioned by several, after reviewing the photos. Hope that was the prob.

The chain, as expected has stretched quite a bit from the initial runs, so I made a chain tensioner. It's working out real nice.

Also mounted the sand tires and loaded it on the trailer to check the fit and ride. Looks good.

A few pics:

tenaja
03-30-2007, 10:26 PM
The chain, as expected has stretched quite a bit from the initial runs, so I made a chain tensioner. It's working out real nice.

Your buggy looks like a lot of fun!

What kind of chain are you using? My chain mfr (I think it was RK) said it's worn out at 1%... with a short chain, that's not a lot of stretch.

Gene
03-30-2007, 10:29 PM
That looks great. I want to see it in person with those paddles. Have fun!

bikelomen
03-30-2007, 11:55 PM
Sure would be nice if My car would friken move. Congrats on your run

K-fab
03-31-2007, 07:34 AM
Great to hear that it's working Dune. *Congrats.

Good looking car indeed.

Go throw some sand and let us know how it does. - video's always good too.

Enjoy the weekend!

nodrog
03-31-2007, 03:12 PM
Hi Dune,

Thats a good looking buggy!

I`m new to this forum but have bben scouring thru for good ideas! One I`m interested in is your chain tensioner, I`ve got one of Dans FNR boxes for my Edge Barracuda and am currently in the process of redesigning the back end to take it. Just a bit stumped on tensioning until I saw yours, what is the tensioning roller?

Thanks for any help.

Bugpac
03-31-2007, 03:27 PM
so did you torque to 300 lbs this time, and you also didnt back it off to get cotter lined up either right, always go forward never backwards they say....I to have snapped a stub on a vw before, it was from just that lack of torque....Looks kick arse, you will no for sure if they will hold up with a few roost from them oversize sand tires... [smilie=biggrin.gif]

dune
03-31-2007, 04:49 PM
Hey bug... The real racing wheels and sand tires are about half the wieght of the btr's w/ desert tires. Feathers compared to the others. I do have my fingers crossed. Hate for a breakdown out on the dunes.

Bugpac
03-31-2007, 06:58 PM
Not the weight but the traction!! [smilie=biggrin.gif]

masterfabr
04-01-2007, 06:58 PM
Only 300#?

The micro stubs used in the Dez are torqued closer to 600# - requires a 5' long bar with one person hanging on the end of it while someone stands on the brakes.If I recall right the 600# is correct from my days ibn a dealership and yes the torque wrench was 5 feet long.Even stomping on the brake it's nearly impossible to get 600# without the VW "special tool". In other words they had to be as tight as you could possibly get them.

boilermaker
04-01-2007, 09:07 PM
I don't remember so good but didn't the VW's have to be torqued so much because the axles had tapered ends. If so then do your axle ends have tapperd ends, if they do then go ahead and torque them to 600#. I thought your axle stubs have splines and only need tighting to hold the hub on, not to also keep from slipping and stripping a keyway.

Bugpac
04-01-2007, 09:27 PM
They are torqued to remove lash in the splines to keep from hammering i believe, they arent a very tight fitting spline on a stock vw...

CBRhino
04-02-2007, 03:03 PM
You might find that you wear through that tensioner pretty quick......we eventually went to a sprocket tensioner because we wore through any delron style rollers within about 20 minutes.......

GREAT LOOKING CAR, by the way!!! *Really nice!!! *Looks like a ton of fun in the dunes!!

dune
04-02-2007, 04:22 PM
Hi Dune,

Thats a good looking buggy!

I`m new to this forum but have bben scouring thru for good ideas! One I`m interested in is your chain tensioner, I`ve got one of Dans FNR boxes for my Edge Barracuda and am currently in the process of redesigning the back end to take it. Just a bit stumped on tensioning until I saw yours, what is the tensioning roller?

Thanks for any help.

Welcome, As funny as it may seem, I'm using one of my sons skateboard wheels as of right now. I'll see how it holds up this weekend. They are very hard and have great bearings in them.We'll see.....

dune
04-02-2007, 04:26 PM
You might find that you wear through that tensioner pretty quick......we eventually went to a sprocket tensioner because we wore through any delron style rollers within about 20 minutes.......

GREAT LOOKING CAR, by the way!!! *Really nice!!! *Looks like a ton of fun in the dunes!!

Your probably right, I'll no soon enough it it works. I'll be able to use a sprocket with my setup as well without too mucch mod.