Does anyone have any tips for removing undercoating from the chassis? I have done the dry ice for interior, but am unsure if it will work for the undercoating? I really done want to use a stripping product due to the mess....thanks

 

Having just finished the floors, I'm having the next one dipped.



It varies by make, what works and I can't speak from Honda experience.

K

 

Kirk can you post how you got them so fresh and so clean?

 

The VWs have these sheets of tar laid on the floors. If you whack them from an exposed edge with a big screwdriver and hammer, flakes fly off - about the size of quarters. The next step is to use a razor scraper to whiz off the larger bits left behind. Finally, I used a green 3M pad and GoofOff to take off the residue in patches about 3x3" at a time - moisten, scrub, wipe with paper towel. Repeat. A lot. And ventilate well.

The good news is that the primer coat under the tar stays intact so it's easy to slather on a coat of my favorite brush-on Rustoleum...

K

 

Do you necessarily want to remove it? Maybe air chissel (not sure) or hammer and scraper or just hammer?

Kirk, not sure how similar they are but I'd do 3 or 4 Hondas (interior) rather than another 944. Might have just been hapenstance but the p-car stuff (played w/ this two times now and it was a major PITA from my perspective) seemed to be impregnated into the metal in comparison.

 

air hammer and dry ice making taking up tar VERY easy.

 

without a rotisserie, how are you applying dry ice to the underside of the car out of curiosity? (never used the stuff - thought you poured it??)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by honda41 &raquo;</TD></TR><TR><TD CLASS="quote">Does anyone have any tips for removing undercoating from the chassis? I have done the dry ice for interior, but am unsure if it will work for the undercoating? I really done want to use a stripping product due to the mess....thanks</TD></TR></TABLE>

Sounds like everyone responding is thinking about the sound deadening tar on the inside of the car, the original poster stated that hes already done this.

I think hes referring to wanting to remove the undercoating on the outside under the car, the protective stuff thats sprayed on as a rust inhibitor etc.

 

the **** doesn't like heat at all, maybe try a heat gun

 

Would it do anything to lengthen the longevity of the underside of the car to just leave the stuff in place? I know it has mass, but are there any convincing reasons to just leave it on?

 

It just melted and dripped away in the areas where my cage base plates were welded in (looked like a fire had occured near the rear brake lines in the wheel well...took me about 20 minutes to realize it was from the rear diagonal struts being welded in ). Maybe he could just weld all over the floor pan inside and have it melt away...

Personally, I'd want to leave it to do it's job...protect the underside of the car from water and such.

 

hahaha ya my job while my cage was being installed was, to make sure the **** didn't catch on fire.


i felt important

 

R crew racing has done it
they stripped the car bare, and brought it to get the undercar tar sandblasted off..
the heat gun and ice ain't going to cut it

 

didn't say ice, but i do think a real heat gun will gu the **** in seconds,

 

the painful way is to just chisel it. you can get some decently long strips of it at a time, but, like i said, its painful, tedius, laborius process...

 

The post above reminds me that where my cage plates were welded on, the undercoating on the bottom and in the fender wells basically just fell off, leaving bare metal. I suppose you could try heating from the inside with a torch, letting it cool and see if it fell off - or could be coaxed off.

Every method that I've ever tried that involved heat and trying to take goo of while hot resulted in a bigger mess than I started with, burns, and a headache. I can still remember the smell of the first car that I did this with - a Chevy Vega...

K

 

I have never taken the undercoating off the bottom of a racecar although I was under my F Prod car the other day thinking about wanting to.

Tom Fowler of OPM Autosports told me they do it quite successfully with a high pressure water sprayer, preferably one that uses hot water or steam to let the heat take effect. I guess just jack the car up as high as you can on one side and go for it.

I have taken the stuff out of the inner fender well of my car both with a heat gun (getting a snoot full of noxious fumes and tough going) and with a wire brush on a rotary too making clouds of particles. Definately the stuff is different than interior sound deadening tar as it seems much more rubbery. I'll try the water gun system as it is reported successful.

 

Sandblasters are made for this kind of thing. I suggest you invest or find a friend who has one

 

a nice selection of wire brushes will get most of it , it will not be fun.

if I had it to do over , I would stripped my car and had it dipped.

 

Where do you have a car "dipped?" What do they dip it in?

 

acid dipped.

nothing can be on the car at all , period , not for the faint at heart...

any racecar builder knows of one in his area.

 

also removes all the factory sealing and typically seam welded afterwards. probably not worth the trouble anyways. you dip a chassis when it needs to be prepared for pro level stuff, no amatuer racing.


Modified by Tyson at 12:46 PM 9/2/2004

 

I was very serious about having my Prod CRX dipped when I built it but I was highly advised against dipping a Japanese car since much of their strength comes from glues and sealers that will be eaten by the acid and not as many real weld as you might think. This was from an RX7 person who sent a shell and recieved a nice loose assortment of body panels back.

That and I was quoted about $1,200 for the dipping. I was hoping for about 1/3 that price and to get a solid shell back.

 

(Assuming here you're talking about the goo they spray on the underside of the car)

Christ and here I think an oil cooler is a hateful job...the undercoating? Wow. What an awful job that sounds like.

The best way would be a sandblaster methinks. But you can't very well put a car in a blast cabinet because, well, it's a CAR and not a control arm. So you're blasting out in the open which is going to create a huge, horrible mess to clean up. Not only do you get to clean up all the undercoating, you get to clean up the sand too.

Ugh.

So alright, I guess that leaves us with acid dipping, which, again, that's a pretty awful job since you have to strip the thing down COMPLETELY. Not to mention the aforementioned thought about glues and such holding some pieces of the car together.

Not for me. The maybe 20 pounds (tops) that would remove, I'll just stay on this diet a little longer.

Now if you're talking about the sound tar in the interior, that's not so bad. Wait till this winter, and go to town with an air chisel. If the car is oldish (mine was 8 years old at the time) it'll come off in big chunks. It was actually kind of fun.

 

btw, this undercoating stuff isnt all that light either. just a couple moments of doing this while i found myself bored and under my car with jackstands, i was able to pick off a sizable amount of weight with a screwdriver. at least on my car it was sprayed pretty damn thick, so its not as insignificant as one would think, but its definately not an easy process, so gotta weigh the cost vs. benefit. then again, if youre already underweight, theres no better place to have some extra weight than down low.