EDIT: New thread in the Road Race forum with new pics. If you're interested, please take a look and add your comments!

New Crosspost:
https://honda-tech.com/zerothread?id=1489227

Crossposting the the Roadrace Forum:
https://honda-tech.com/zerothread?id=1483618

I had a rear subframe crossmember fail on my road-race CRX. Does this look like something you could weld up and fix? TIG? MIG? Hot arc? Cool? Any advice would be much appreciated.

-- Jon








Modified by Sterndotstern at 10:01 PM 1/10/2006

 

It could be welding, but you'd have to take it to a structural welder. It would be done with stick.

Probably cost you close to the car's value to do a quality job. Otherwise, I don't see how it would be safe to drive the car or sell it to anyone else.

 

Dam thats nuts. How did that happen?

 

Structural welder? ****, those parts are just tacked together from the factory.

 

I would take it to A body shop and let then put it on the frame machine to realign it and they can weld that back together (seam weld the whole thing)and reinforce it for probably less then $500, but if you get the whole rear member replaced them that would be expensive. You should be able to find A body shop to fix that though, and what did you hit I see the lca is bent.

 

That's why they make JB weld buddy!!

a TIG or Mig would be fine. proably use some 16 guage mild steel as a backer inside the subframe. drill holes alot of holes in the subframe and rosette weld the backing plate to the subframe from the outside.
then rosette weld the subframe back to the floor. add some stitch welds there also. make like a 1/4" gap between the cracked sections. then weld a nice bead into the cracked center of the subframe. the backing plate will help with this. probably run a full bead on each section overlaping onto the backing plate. then another bead or two down the center to join all the beads.

if that was my car i would be satisifed that the repair would be way stronger then how the car originally came.

 

nice avatar Dragline

 

edit... nevermind, i read in your other post that you already tried ordering a new one ah well.

 

you must change the pieces its spot welded
on your body you drill the spot and weld the new pieces on the car
its not really expensiv i think under 100$ can at dealer
good luck

 

seriously...just go buy the part new from honda

DO NOT try to "salvage" one off of another car.....in the process to return an old comp4 car back to "legal" status.....a certain person tried to take one off a car in the yard...and it just didn't work. spent more time ******* with it than it was worth. went to honda...couple bucks later...brand new parts are on and good

 

Thanks for all the advice, guys.

It looks like a new part is out of the question, unfortunately, and since removing one of these from a junkyard car can potentially damage or destory the part, that plan is out too. None of the parts sources I've contacted are able to deliver the part, since it's been discontinued for a couple years.

It looks like I'm going to have to weld it up. I've added another post in the road-race forum with a possible design for repair, but wanted to get input from the more experienced welder/fabricator types in here as well.

https://honda-tech.com/zerothread?id=1489227

Feel free to take a look and post your responses!

 

no you cannot weld that...

Why you ask?

Because that metal's integral strength will be SEVERLY comprimised if you heat it. The cheap metal that we make our cars out of is actually quite complex.

 

Damn thats crazy.

 

even if you could... would you really want to?

 

you can definitely weld that. if the metal was so "COMPLEX" and exotic then chances are it wouldn't have cracked in the first place.
it's just mild steel, nothing special. Honda does not HEAT TREAT there cars after spot welding all of the panels together!!! plus it would be VERY difficult for most to repair if it was such a special process or material.

definitely do NOT use a stick welder though. the heat effected zone will be too large and you could warp the metal. plus it's just not a really good method for welding on sheet metal and cars.
at least use a mig. and don't weld it all up at one time. let it cool down a bit after a few seconds of welding.
an overlapping backing plate behind the crack will be fine. just welding in the crack would hold but maybe not for long. each side of the crack has been work hardend and the weld and surrounding area would be brittle.
drill a few more holes in from ontop of the floor of the car and add in more rosette welds (spot/Plug welds) onto the subframe. a few stich welds every 4-6 inches would also be a decent idea.

 

lots of different opinions... I personally would weld it. Jack the car up by the subframe and line the pieces back up. Weld them up wiht a mig, then STITCH the frame to the floor. Im amazed it broke like that. If I were you, I would get some 3/16" steel U channel or some flat bar and brace it.

Use a MIG on it, dont stick weld it. Seems like some of these guys are babies when it comes to structural repair. You guys need to go out to a bodyshop and see what they can and cant fix. You would be AMAZED how much is fixable

 

Thats easily weld able..
Dont listen to half the BS on here.. Its cake to do!

http://www.rfdm.com/gallery/album32?page=5
thats a similar thing.. No problem to fix at all!

 

Fine to fix and sell...not fine to fix and race. The HAZ will expletive up the integrity of the metal..i don't care what these yayhoo's say. In typical body work fashion these tards don't have a clue what goes into the material science of making a car from 20 gauge steel. Typical body shop people will tell you MIG because they know if you tig it or stick it...the HAZ will be very large and your metal will fatigue so bad that it wont stand ANY stress. The MIG weld has less HAZ but it will STILL have it and therefor comprimise the integrity of the metal. So, moral of the story...if you want to race it...replace it. If yout want to fix it and sell it...weld it. I guarantee if you weld it and race it...it will crack within the year.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ~RTErnie~ &raquo;</TD></TR><TR><TD CLASS="quote">Fine to fix and sell...not fine to fix and race. The HAZ will expletive up the integrity of the metal..i don't care what these yayhoo's say. In typical body work fashion these tards don't have a clue what goes into the material science of making a car from 20 gauge steel. Typical body shop people will tell you MIG because they know if you tig it or stick it...the HAZ will be very large and your metal will fatigue so bad that it wont stand ANY stress. The MIG weld has less HAZ but it will STILL have it and therefor comprimise the integrity of the metal. So, moral of the story...if you want to race it...replace it. If yout want to fix it and sell it...weld it. I guarantee if you weld it and race it...it will crack within the year.</TD></TR></TABLE>

I would take you up on that bet...

I would also put a piece of 1/8" angle iron inside it and weld it as a plate to tie the entire piece together.. It would be strong as hell!

 

I bet you a honda-tech sticker. winners choice of color.

 

Now that I think about. It's not nearly as difficult as I thought it would. Brace it up pretty well from all sides and I think you will be in good shape.

 

if your exotic steel is t1 hardend steel..preheat, mig weld with high tensil stregth wire, post heat and peen you weld with a chippin hammer to stretch the mig weld. peening only nessasary if you weld starts to crack as soon as it cools. dont use angle iron or U shaped stiffners cause it wont let it give like it should resulting in a cack at the end of your stiffner. use football shaped plates.but make sure you dont weld all the way around the football plates instead make 1 inch long pigtails at the points of the football- 4 pigtail/piece ..then post heat

 

I have seen good welders/fabricators put halves of Hondas back together in the middle of the car! as long as you cut it out, weld it from the inside with reinforcement it will be fine. how much weight is really on the rear for the car anyway? if you can't get that fixed to hold 1000 lbs or less, something is wrong...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Want2race &raquo;</TD></TR><TR><TD CLASS="quote">

I would take you up on that bet...

I would also put a piece of 1/8" angle iron inside it and weld it as a plate to tie the entire piece together.. It would be strong as hell!
</TD></TR></TABLE>

I would too... That's an easy fix and i'll also bet it would never crack again if done properly no matter what form of racing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ~RTErnie~ &raquo;</TD></TR><TR><TD CLASS="quote">Fine to fix and sell...not fine to fix and race. The HAZ will expletive up the integrity of the metal..i don't care what these yayhoo's say. In typical body work fashion these tards don't have a clue what goes into the material science of making a car from 20 gauge steel. Typical body shop people will tell you MIG because they know if you tig it or stick it...the HAZ will be very large and your metal will fatigue so bad that it wont stand ANY stress. The MIG weld has less HAZ but it will STILL have it and therefor comprimise the integrity of the metal. So, moral of the story...if you want to race it...replace it. If yout want to fix it and sell it...weld it. I guarantee if you weld it and race it...it will crack within the year.</TD></TR></TABLE>

I'll take the bet also,
So all the guy's that seam weld or stitch weld there chassis are doing it to make the car weaker?