92RS_Ttop

iTrader: (3)

I'm getting ready to paint my engine bay, and the thought of sanding all those little nooks and crannies is depressing me. Has anyone used a deglosser instead of sanding to prep the surface for paint? I'll be painting it a semi-gloss black with enamel if that matters. I'm not looking for show quality, just want it to look nice and finally get it all one color. I had to replace the core support and driver's wheel well due to the PO wrecking the car before I got it and they are gray while the car itself is red.

ZsTransAm

I've never heard of a deglosser for auto use. If a body shop doesn't use it, its probably a bad idea for you to try.

mantaguy

iTrader: (5)

Same here,the only Deglosser I ever herd off,was for Epoxy floors.

steve87ta

iTrader: (4)

There used to be a jam-it product for what you are doing. It softens the Paint for recoating. I think it was hazzardous. Havent seen it around for a Long time. Old body guys that I know loved it.

92RS_Ttop

iTrader: (3)

I found mention of the jamb-it product on other forums while I was searching, but I need something that not real toxic. My garage is under the house and is open to the basement so I don't want the fumes in the house. I've painted in the garage before, and it doesn't really get into the house, so it might be ok, but id rather not risk it. It also seems like you need to paint over it right away, and I need something that I can wait a few days before painting if need be.

I'm thinking of maybe just using whatever I find on just the hard to get to areas, and sanding the easy parts.

racerx520

iTrader: (1)

i found a surface prep stuff at my local napa, according to them, before maaco paints a car, thats all they use. not sure if thats true or not but figured i'd chime in

ZsTransAm

That would explain why MAACO paint falls off

That is interesting though, never heard of the stuff

camarotucker

iTrader: (2)

I will ask PPG on Friday, but I have never heard of it.

I would use a scuff pad for removing gloss. For hard to reach areas they can be folded. For really hard to reach areas, wheel well to firewall comes to mind, you can use a mixing stick to stuff it in there. I would use grey for black, but some guys get away with maroon. I don't get away with anything.

stealtht/a

iTrader: (1)

We used to use deglosser for boat hulls way back. Doubt it's still available most places as it was super toxic and fumey. It was used when owner wanted a cosmetic paint on top of good condition paint, such as when we took delivery of the new, white hull but the owner wanted it blue. Scuffing 500 square feet of paint takes a while and labor is most expensive.
We would use wax remover first, then spray on the deglosser. I think it had a special sprayer. It was super critical on the timing, had to start spraying paint as soon as we were finished deglossing. If we waited too long or it was hotter than calculated, the original finish would turn to orange peel and then have to be sanded . Make it even bigger job!
As I said, the stuff was nasty, I have no desire to use it, much rather sand.
I think the jamb it stuff is the same stuff as the clear coat blending agent. Don't think that's avail everywhere either. It's an aerosol you spray on a clear coat seam to blend it out when doing a mid panel patch. I don't use it. Prefer to hide the seem at a panel break.
You really want to sand your project anyway. There's no way your 20+ year old paint is still in good enough shape that you want it as the base. It's been exposed to heat and oil for a long time. Personally, I would sand to the primer everywhere and sand to the metal anywhere the primer has failed too. There will be rust bubbles starting.
You really need to sand it. Invest in a nice array of sanding blocks , including little ones for hard to reach corners. Cheap electric detail sanders are good for that area too.
Even if you aren't going for show car, poor prep is going to make the new paint bubble and peel in an engine bay.

racerx520

iTrader: (1)

92RS, you'll have to let me know what you wind up using, i'll be getting ready to paint my engine bay in a couple weeks right before i do my engine install. keep us posted.

92RS_Ttop

iTrader: (3)

The original red paint is in really good shape. I could really just clean it and paint the other side to match. All rust has been replaced with patch panels for holes. The areas that were just surface rust have been sanded and treated with a rust converter. The gray paint on the replacement parts is cracked pretty bad, but not peeling anywhere.

I have a small detail sander I will be using on the larger surfaces, I really just want to use the deglosser on the areas between the wheel well and firewall and under the upper side rails where the fenders rest on. Basically the areas you don't really see. I experimented a bit yesterday and found that lacquer thinner works really well to take the gloss off, and with a little more rubbing I could get down to the primer. So I may just use that since I've got about a half gallon of it.

ZsTransAm

Do it if you want to, but your paint will eventually fall off on the places you cut corners. You need something for the new paint to bite into, you can take the paint off with lacquer thinner but it will still be smooth so it won't do you a bit of good unless you also sand it. I'd rather see you spend an hour with a red scotchbright and just seal it than waste your time with the lacquer.

The clear coat blending agent that Stealth is talking about is still available but it just thins out the new clear coat, it won't soften up the old stuff. Its always best to avoid clear blends anyways.

stealtht/a

iTrader: (1)

Yup, wouldn't be so many sets of sanding blocks for sale if there was a replacement for sanding prep !

callmechaz51

Unfortunately, and I say this from considerable experience, deglossers, liquid sandpapers, and paint strippers that are "less toxic" or "green"...suck. Ninety-five percent of the time they simply don't work at all. That includes house or auto type products. I used to use a NAPA product for "sanding" jambs and it work fantastic! Not sure what big brother has left for us to use nowadays, but the green products are, at best, "cleaners."