E-Bodies.org Cuda Challenger Forum

Technical Shop => Body Shop => Topic started by: nsmall on March 27, 2017, 11:34:10 PM

Title: Undercoating
Post by: nsmall on March 27, 2017, 11:34:10 PM
Thanks for all of your help folks.  I really feel at home here.

My plans are to strip my Cuda real soon and have it media blasted.

As for the undercoating in the wheel wells and underside, everyone says the undercoating has to be removed by hand.

My question is, Can I just leave the factory undercoating and whatever gets removed by media blasting...great, as for what stays, just leave it?

Im not building a show car.  Besides appearance, what is the point of removing all of the undercoating?  Im assuming on the rear quarter down low the inside of the quarter has a panel on the inside, can this be replaced as this is one area I am concerned there is rust in between it and the actual quarter panel.

Im not painting the underside body color.

:thankyou:
Title: Re: Undercoating
Post by: Tunis on March 28, 2017, 05:03:35 AM
If you don't remove it, how will you know what the state of the metal beneath it is? Blasting will not work no.

I used a needle hammer to remove mine. It's a lot of hard work with vibrating tools which is not ideal for your body..
Title: Re: Undercoating
Post by: 750-h2 on March 28, 2017, 05:34:03 AM
Just remove it to make sure. I use a heat gun or propane torch to heat up the undercoating and then use a scraper to peel it off. Not really hard to do.
Title: Re: Undercoating
Post by: anlauto on March 28, 2017, 05:36:49 AM
There is rust under that undercoating, guaranteed  :alan2cents:
Title: Re: Undercoating
Post by: MoparDave on March 28, 2017, 05:58:52 AM
As Alan mention. rust will grow under. I would torch/heat gun and putty knife it off to insure there are no surprises.
Title: Re: Undercoating
Post by: soundcontrol on March 28, 2017, 06:35:21 AM
Agree with everybody else, you need to remove it, it's very easy with a torch, heat it up and scrape off. I put my son to do my 2 cars, he actually liked it, and did a great job.
Title: Re: Undercoating
Post by: usraptor on March 28, 2017, 08:45:41 AM
Quote from: soundcontrol on March 28, 2017, 06:35:21 AM
Agree with everybody else, you need to remove it, it's very easy with a torch, heat it up and scrape off. I put my son to do my 2 cars, he actually liked it, and did a great job.

:iagree:  I agree.  That's how I took off mine.  Fortunately for me there were no rust issues underneath!  :twothumbsup:
Title: Re: Undercoating
Post by: RUNCHARGER on March 28, 2017, 08:55:34 AM
I agree: It's best to torch it off, clean and coat everything and reapply. I know it seems counterproductive but there will be rust underneath it.
Title: Re: Undercoating
Post by: nsmall on March 28, 2017, 05:28:31 PM
Thanks guys.  Really appreciate the help.  I will remove the undercoating.  I actually enjoy a job like this.  There's not much undercoating  under  the car.  Just need to find time.  I have 2 babies right now.

I'll try the torch method.

Thanks

Neil
Title: Re: Undercoating
Post by: Aar1064 on March 28, 2017, 06:23:13 PM
Not sure how much is on your car or whether or not it'll be on a rotisserie but I removed the undercoating from mine using a hot water high pressure washer. It took about 4-5 hours to remove entire undercoating from underside. I rented it locally on a weekend. Nasty job as I was covered in the stuff from the spray back.
Title: Re: Undercoating
Post by: A.Gramz on March 28, 2017, 06:39:38 PM
Quote from: Aar1064 on March 28, 2017, 06:23:13 PM
Not sure how much is on your car or whether or not it'll be on a rotisserie but I removed the undercoating from mine using a hot water high pressure washer. It took about 4-5 hours to remove entire undercoating from underside. I rented it locally on a weekend. Nasty job as I was covered in the stuff from the spray back.


:bricks: why didn't I think of that. Heck I own a hot water power washer  :headbang:
Title: Re: Undercoating
Post by: Cuda Cody on March 28, 2017, 06:41:43 PM
That hot water pressure washer is a great idea!  And it looks like it did even a better job then I can do with a torch and putty knife.   :bradsthumb:
Title: Re: Undercoating
Post by: A.Gramz on March 28, 2017, 06:45:35 PM
Quote from: Cuda Cody on March 28, 2017, 06:41:43 PM
That hot water pressure washer is a great idea!  And it looks like it did even a better job then I can do with a torch and putty knife.   :bradsthumb:

I agree on better job and no tar burning fumes looks like a win win. 
Title: Re: Undercoating
Post by: Aar1064 on March 28, 2017, 07:50:33 PM
It actually worked really good and as you know some spots were really thick. On these areas, I'd let the hot water soften it up then put the pressure on it.

Goggles and face sock are a must. The undercoating is being pulverized into fine sandy particles and it gets all over you because of all the directions the water takes as your spraying past all,the holes and crevices.

I covered entire car in plastic and taped up all the rubber plug holes as best I could to keep so much water from getting in it.
Title: Re: Undercoating
Post by: nsmall on March 28, 2017, 08:01:04 PM
It will not be on a rotisserie so pressure washer is a no go.

I'm less worried about the underside as it looks real good.  The wheel wells look like the real challenge.

Has anyone ever tried the heat gun option as the last thing I need is a fire with the torch?  :help: Then again the car will be a shell when I strip the undercoating.
Title: Re: Undercoating
Post by: A.Gramz on March 29, 2017, 02:58:28 PM
Heat gun is just slower will work but slower good luck worst part of my restoration so far
Title: Re: Undercoating
Post by: Aar1064 on March 30, 2017, 07:51:35 PM
I used Aircraft paint remover and a oscillating tool with a scraper attachment to scrape the undercoating on the inside of front fenders. It's nasty and protection for hands and a respirator should be used as I'm sure you know.

Title: Re: Undercoating
Post by: 340challconvert on September 20, 2017, 01:20:34 PM
Cleaning up my front and rear wheel wells/inner fenders of the factory undercoating.
Used a Dremel oscillating tool with a hard scraper
Was labor intensive, but the under coating came off relatively easy, then used sharp chisels (gently)  and brake cleaner to clean up the residue, then DA'd with 80 grit.
Granted this was in the wheel wells only and was not the entire bottom floor, and it was still several hours worth of work for each wheel well.
In the first pic you can still see the original undercoating pattern.
Before and after pics
Title: Re: Undercoating
Post by: nsmall on September 20, 2017, 04:06:10 PM
Looks beautiful.  Now stay off gravel roads.
Title: Re: Undercoating
Post by: 340challconvert on September 20, 2017, 06:37:25 PM
Quote from: nsmall on September 20, 2017, 04:06:10 PM
Looks beautiful.  Now stay off gravel roads.
Yes-time to imitate the factory coating.
Title: Re: Undercoating
Post by: 340challconvert on September 27, 2017, 07:01:22 AM
Finished the front inner fenders which are now painted and starting the rear wheel wells.
Wanted to make sure there was no rust on the welded seams.
Using a dremel osculating scraper, very sharp wood chisels and wire wheels in a drill.  NO FUN, a lot of labor, but it works.
I like the heat gun idea, garage is underneath the living area of my house, so I prefer not to use a torch (car is not mobile)
This is like "torchure", and by far the worst job so far on my resto: so the torch idea is sounding more feasible (with a respirator and good ventilation) 
Some pics on the driver's side wheel well.  Seems look good so far!