Chrome Straight axle - Almost got me bumped at tech - WTF

My Scout has a chrome straight axle from way back in the 70's. I was getting the truck teched yesterday at the Drags (IHRA) and the tech official almost bumped me from the event due to the chromed axle.

Something about weakening the metal from the chroming process. Also, something about the chrome hiding cracks and IHRA trying to stop people from hiding welded suspension parts with the chrome. The last point I fully understood and agreed with.

Has anyone else experienced this?

Are there any tech guys out there who can shed some light on this ??

Ultimately they let me run. (The Scout was too cool not to let it run). I had every intention of stripping the existing chrome this winter. Now I guess I'll be powder coating it instead of re-chroming.

 

Hydrogen embrittlement.

 

http://www.finishing.com/1600-1799/1747.shtml

http://en.wikipedia.org/wiki/Hydrogen_embrittlement

 

It was mentioned elsewhere that nickel plate doesnt make it brittle, so that could be an alternative if you NEED the shinny stuff

 

So how did the Scout run. I was there for the Fri night drags, damm it was cold.

 

They must be worried about powdercoating and paint hiding imperfections as well, no?...you can't hide shit with chrome, if it's a shitty looking part and you chrome it, it's now a shiny shitty looking part...you can hide all sorts of defects with powdercoating and paint...I understand the hydrogen embrittlement concerns, but the rest seems backwards to me...

 

I don't buy the hydrogen embrittlement argument. How many top fuel dragsters over the years have had chrome front axles? How many of those cars have had catastrophic failure due to chroming? Show me the proof and the pictures of the so many cars that had failures due to this problem and I'll believe it.

 

Is this true? If they nickle plate it first then chrome it, will it still get a chance of hydrogen embrittlement?

 

So no chrome wheels?

 

I am not a tech guy but I have heard for years that chroming parts weakens them. I have never heard of someone being bumped for it.

As for stripping the chrome that will not strengthen the axle the damage has already been done. As for powder coating or ceramic coating I have to assume that the same problem will exist the cracks or welds will be hidden, if that is the reason for bumping I have to believe that the same problem will exist at tech.

 

Am I right to assume you have a cast (dropped) steel axle??? I've heard of tech guys dis-allowing welded cast steel axles, and that would explain why the question of chroming..

 

Was thinking the exact same thing - damage is already done. Don't current drag gods run their chassis (and I assume suspension pieces) in bare metal and just keep them oiled/Scotchbrited now for tech reasons?

Steve

 

It's my understanding, the "hydrogen embrittlement" issue comes into play, only on a high strength, "heat treated " part.......................A forged steel, nor a cast steel axle, meets neither of those criteria, I don't believe...............................Though I could be mistaken!

 

Just because a part doesn't break isn't proof the metal hasn't been effected.

I don't remember the specific times and temps; If the part is heated within a short window of time after plating, at a specific temperature, for a minimum period of time, the effects of hydrogen embrittlement are either mostly or completely eliminated. There is no way the tech guy could have told if that was or wasn't done.

Nickel plating does cause embrittlement. The reason I know that is because I have had many parts plated by a shop that only does [electroless] nickel plating. For some jobs/customers they bake the freshly plated parts.

To remove the effects of hydrogen embrittlement it would be necessary to remove a thin layer of metal from the entire part. That would be the same as the smoothing, polishiong, and buffing originally done prior to plating the part. It is doable, but it's a tedious, dirty job. It also wouldn't hurt to check the part for cracks prior to investing all that effort.

All show chrome plating is either copper-nickel-chrome, or nickel-chrome.

Ordinarily carbon steel can be effected by hydrogen embrittlement. It doesn't matter whether the material has been cast, forged, drawn, etc. While I'm not 100% sure, I don't believe it matters whether or not the part has been heat treated. But, it makes sense that making a hardened part more brittle would a bigger problem than doing the same to a softer part.

 

Just call it Chrome-Moly, but without the Moly.

The 'chrome hiding defects'-part sounds bullshit to me aswell.
There's way more to hide with regular paint than chrome.

 

Did this "tech" have anything in writing from IHRA?

 

What a load of BS. There's tons of rails and funny cars running chrome front axles, and they don't get hassled. Somebody is just screwing with the average guy.

 

I think the issue is that a part IMPROPERLY chromed can exhibit hydrogen embrittlement. The issue now becomes - how can you tell by looking at it? You can't. That's why they are trying to crack down on it ;-)

 

Hydrogen embrittlement is not a function of proper or improper plating, it is inherent to the process.

 

Been racing this 2 years and went to nhra bowling green (tough teck) but never had any issues. YET.............................................

 

Facts not withstanding, some tech guys have the same mentality as some bureaucrats. They will ruin your day because they can. Or at least think they can.

 

actually from what i have read after the part has been chromed , it is supposed to be put in a oven , and heated slightly for a period of time , this is supposed to cure problem , however some plating shops dont do this ...which would be improper plating , a few years back a company was making replica captin america motorcycles all the chrome frames broke .... you woulod not be able to tell a part that has been cured from one that wasn't just from visual inspection

 

Can't speak for the IHRA, but the NHRA hasn't allowed chrome on a cage, frame or suspension component for at least 20 years.

 

With any event you can get a tech that is having marital problems. Then he decides that he doesn't like the way you look or that you look like the guy that is causing his marital problems and shazaaam you get nit picked.

In the '70s we got bumped for a throttle spring that didn't look up to par. No biggy we just had to go back to the pits, change the spring, and go through the process all over again. There wasn't anything wrong with the spring and I don't recall there being any documentation as how to tell if a throttle spring is good by looking at it.

After we made it to the final round the fella took us to dinner. Said, "no hard feelings? " We just blew it off as he was having a bad day and we were available.

Now the chrome axle that is a different story. They may be cracking down on them. The best way to tell is file a grievance, maybe someone will send you a copy of the memo. But you might have to avoid that tech for awhile, like forever.

 

Baking is not a routine part of the plating process. Most shops offer the service, but many parts don't need it. In many cases the shop has no idea what the part is or how it will be used. I agree that when given what is obviously a structural automotive part, the shop should at least offer to bake it, but it is up to the customer to tell the shop what they need and want. I made mechanical exhibits for a number of years, at one time or another I was involved with a number of show/concept cars. Before that I restored classic era cars for a number of years. Over time I have dealt with quite a few platers. In every case it was my responsibility to let them know if something needed baking.

Why wouldn't they just automatically bake parts? A major reason is that it takes time and costs money to do it. From flatwashers to connecting rods and earthmover axle shafts, I had many thousands of parts plated every year. While a plated control arm, 1/2 shaft, or steering knuckle would usually benefit from being baked, if the part is for a display or showpiece car, the part has to do little more than look good. Baking those parts would have been a waste of money and usually precious time. It was up to me to let them know when a part needed baking. And as I already mentioned, that was the case with all the plating shops I have dealt with. Some shops specialize in hot rods, motorcycles, or bumpers, but most shops aren't staffed by motorheads. So as I said, you can't assume they know what they are plating or how it will be used.

 

You said it better than I could have. Bravo.

 

no ofense but i am still sticking with improper plating....you can place the blame on who ever you want , the fact is if a axle or a spindle , steering arm..ect has been plated and not baked i would call that improper plating ...i have heard of shops that just don't have the facilitys to bake the parts..

.i would however think the chrome shop should advise or know of problems with structural parts i cant think of anyone told "ok you want this chromed ,,,if it is a structural part it should be cured by baking it so it doesnt crack and your wheel fall off in the future.......whoes gonna say ....no i dont want to spend an extra 50.00 ....i'll risk it?

 

Having been a NNHRA and IHRA tech for many years It wasen't on our list but that was 6 years ago. I have seen thousands of chrome front axles and wheels and never ever saw a failure due to plating.NASCAR race teams at one time all used chrome wheels as did millions of hot rodders over the world for years so I would say there is a very slim chance they would experience any type of failures. Any thing is possible when you push performance to the limit but I just never ever saw any of it as to chrome parts.

 

X2.........common mistake for some newbies to racing in an organization with a real tech department. It is also at some Nostalgia events for this to be overlooked as they have some give-n-take they abide by. I know several tech guys at Bowling Green (NHRA Hot Rod Reunion) and they will work with you if your willing to listen. It also depends on the overall build quality of the car. If it is kinda ratty everywhere....they'll crack down. Unfortunate but true !

 

I had a Ford 3/4T 4x4 that 2 of the wheels had slow air leaks, eventually found the small cracks in the wheel in the chrome. So chrome wheels will crack on a street truck, think what can happen on a race car suspension.