Removing undercoating... needle scaler?

[1BAD68]

I don't have one and wondering if it would be useful for undercoating removal from wheel wells, etc?

[Silver R/T]

Heat gun or propane torch and a scraper. Have fun

[matrout76]

i've been using a multi-tool with a scraper blade and it works pretty well.  It takes off almost all of it and just leaves a thin black film in areas, about what i'd expect using the torch and scraper method.  I'm going to try hitting a scraped area with some paint stripper and sand blast it to see which works better.

The tool i have is this one:  http://www.menards.com/main/tools-hardware/power-tools/multipurpose-tools/performax-shockwave-103-piece-multi-tool-kit/p-1897062-c-12869.htm

actually...i've been paying the neighbor kid to come over and scrape on it.  He has about 2 hours on it and is about 1/2 way done with the entire underside. 

[johnnyseville]

Best method I found is using a torch used for roofing, it is quick, but make sure you know how to use it and keep an extinguisher handy.  You torch and have a friend scrap it off quick, can do an entire underside in about 2 hours. 

[Dino]

Is this the same car you painted a while back?  Dry ice works best to remove the undercoating but it'll remove pretty much everything else as well.  Why do you need to remove it by the way?

[Indygenerallee]

heat gun with a dynabrade!!!!

[1BAD68]

Is this the same car you painted a while back?  Dry ice works best to remove the undercoating but it'll remove pretty much everything else as well.  Why do you need to remove it by the way?

Yes same car. I want to remove it due to overspray and chunks of it have fell off.
It's hard and brittle (45 years old) and think the torch and scraper would just make a mess.
I think I'm going to get a needle scraper and try it. If it doesn't work at least I have another tool in my arsenal.

[Dino]

Is this the same car you painted a while back?  Dry ice works best to remove the undercoating but it'll remove pretty much everything else as well.  Why do you need to remove it by the way?

Yes same car. I want to remove it due to overspray and chunks of it have fell off.
It's hard and brittle (45 years old) and think the torch and scraper would just make a mess.
I think I'm going to get a needle scraper and try it. If it doesn't work at least I have another tool in my arsenal.

First thing I would do is scrape away all the loose flakes, without additional heat.  Then see what you uncovered.  If the metal looks good then theoretically you can simply put fresh undercoating over it, but it won't look great.  I've used a small amount of sealant to smooth out the patches before an then resprayed it.  It'll look good and be just fine for a driver.  If you want to make them look as new though you can use a power tool with an undercoating remover like this: http://www.thetoolwarehouse.net/p-19097-dent-fix-equipment-df701.aspx

You don't have to buy that exact tool, they have similar steel wire brushes that fit on your drill.  Those work fine.  It works real nice because there's space between the brushes.  When you hit the undercoating it takes it down to the metal in small strips, very easy to do and not as messy as using a torch.  Still messy enough that you want to have protective gear and cover up the wife's car though.   

You can also feather the undercoating with this so you don't have to take it all off if you don't want to.

Be sure to use several layers of duct tape on the wheel well lip because if you accidentally hit it, the brushes will pull themselves over the edge and ruin your paint job.

[bobs66440]

Just keep in mind that the old undercoating contains asbestos in most cases. 

[Dino]

Just keep in mind that the old undercoating contains asbestos in most cases. 

Damn I never thought of that.  I wonder how much cancer I have in me after doing this stuff for so many years.   

[cdr]

Just keep in mind that the old undercoating contains asbestos in most cases. 

DONT say that too loud!!! or the goobment will come & confiscate all our old mopars 

[Troy]

i've been using a multi-tool with a scraper blade and it works pretty well.  It takes off almost all of it and just leaves a thin black film in areas, about what i'd expect using the torch and scraper method.  I'm going to try hitting a scraped area with some paint stripper and sand blast it to see which works better.

The tool i have is this one:  http://www.menards.com/main/tools-hardware/power-tools/multipurpose-tools/performax-shockwave-103-piece-multi-tool-kit/p-1897062-c-12869.htm

actually...i've been paying the neighbor kid to come over and scrape on it.  He has about 2 hours on it and is about 1/2 way done with the entire underside. 

I've used one of those tools and it works pretty good. I generally use a knotted wire wheel on my grinder though. It is faster but both make a HUGE mess. Cover yourself from head to toe and definitely wear a face mask or you'll be black! I have also used the torch and scraper routine and it's much cleaner for the surrounding area (ie garage) except for directly underneath the area you're working on. At some point you will catch it on fire so be prepared. I'd love to try the dry ice method.

Troy

[1BAD68]

Dry ice? Please explain how that works.

[six-tee-nine]

Easy, turn the car upside down if on a rotisserie, put dry ise on it. Wait, then beat on the coating with a hammer and it'll flake of.

However I have never tried it myself, but i've been told it works well. Due to the extreme coldness of the dry ice the coating becomes very brittle and can be hammered of  nicely.

I use wire wheels for this, almot less smoke, goes pretty fast imo but is still messy since the melting stuff flies all over the place....... dont think there is a not messy way to remove that goop...

[Dino]

Dry ice? Please explain how that works.

Like six-tee-nine says or blast dry ice as you would any other media.  The extreme cold makes the undercoating shrink, get brittle and lose adhesion.  You can throw dry ice all over your floorboards, come back later with a mallet and start pounding.  Undercoating will come off the bottom and paint on the inside will crack and release from the panels.

[Hudson Hornet !]

I seem to remember someone using a steam jenny for paint as well as undercoating?  Can someone elaborate on this?

[XH29N0G]

Dry ice? Please explain how that works.

Like six-tee-nine says or blast dry ice as you would any other media.  The extreme cold makes the undercoating shrink, get brittle and lose adhesion.  You can throw dry ice all over your floorboards, come back later with a mallet and start pounding.  Undercoating will come off the bottom and paint on the inside will crack and release from the panels.

Just don't do this in an enclosed space or you might end up like 

[Mopar1979]

I just finished today on my 69 se and I have had all the fun I want I used exactly what you said a needle scaler and a vibratory tool with a scraper blade from harbor freight. The needle scaler worked great in the wheel wells, inner fenders, underbody for the most part. Where they was no paint underneath undercoating it was hard to say the least to get it off. I even used aircraft paint remover to help soften the stuff. I must say this was the nastiest job I have ever had to do on a car be careful not to push too hard on the floor pans if they have some rust cause you will do what I did and poke some holes thru the drivers floorboard. I was going to replace anyway I just found out how much. I will say they had no consistency in the thickness as they spray everything. Good luck! Now off for blasting 

[Troy]

Oh yeah, that's the thing with the knotted wire wheel too - pinholes become BB sized and/or a whole string of them becomes a gash. About the same as blasting though.

Troy

[FLG]

One of these works great

https://www.youtube.com/watch?v=jzv38W1DDic


Cheap too.

[bobs66440]

One of these works great

https://www.youtube.com/watch?v=jzv38W1DDic


Cheap too.

That's cool 

[JB400]

Looks like a new toy for me to buy.

[Mopar1979]

That's what I used. You can get it in sale from harbor freight for $19.99 on sale. Get earmuffs cause you gonna need em!

[Patronus]

I use a Fein brand (the original) everyday being a contractor. Its my magic wand!

[six-tee-nine]

One of these works great

https://www.youtube.com/watch?v=jzv38W1DDic


Cheap too.

Huh really need to get me one of those....