Chemical dip vs Media Blasting

[Ryan Adkins]

No worries, that’s my understanding as well.

[Dpmulvan]

After that you would epoxy prime

[Ryan Adkins]

Gotcha

[Dpmulvan]

I just know a few guys on here had their cars dipped and were not happy as they started rusting.
These days it’s hard to trust people to do a proper job, and as 962 said if something doesn’t go well and you have too many cooks in the kitchen the finger pointing begins and ya end up screwed.

[Ryan Adkins]

Yeah, that makes sense. I will just need to be on top on the scheduling if I have separate places do the work.

[962porsche]

like what Dpmulvan stated about epoxy primer.
for the interior we would leave the e-coating sand it with a red pad and or 320 grit then spray it with an epoxy sealer and going wet on wet right over it with our color AKA top coats.
for the exterior we would pretty sand the e-coating off with 180 grit then spray two coats of epoxy over the exterior panels . we would do our body work and once that was finished we would sand the hole car again with 180 or 220 and spray one coat of epoxy sealer over the hole car and wet on wet after the epoxy sealer flashed off spray a few coats of a filler primer.
the filler primer will offer a higher build than most epoxy primers do. this will give you better mil builds for block sanding for top coating.

[Ryan Adkins]

@962porsche Thank you for the very detailed information. This will help me in my planning.

[rich]

When they get this far apart Dip and E-Coat is really slick. No body filler allowed. All new Medcedes Sheet metal. outer body panels, All inner panels, floors, trunk floor and tail light panel. All spot welded like the factory, butt welded and metal finshed shroud and quarter panels.

[ChrisHamilton]

E-Coat means electrostatic deposit coating not epoxy coat. Properly applied quality epoxy (not PPG DPLF)is far superior to EDP type coatings.

[rich]

Pretty hard to submerge a whole car in a vat of epoxy primer. My bathtub isn't that big. You will never reached this level of prep in shop conditions. The Mercedes was cooked at 800 deg., dip stripped, rinsed and the entire car was submerged, electrically charged in a controlled process.

[ChrisHamilton]

No argument from me that EDP is great for getting into all the nooks and crannys. I wasn't advocating dipping in a vat of epoxy, I was correcting what several had said earlier in this thread that E-Coat was epoxy., which it isn't. As for my preference for epoxy, I was speaking to the durability of it, the corrosion protection and superior adhesion of the stuff. Not to mention the fact that it is flexible.
That is a nice process you showed. Did you do the work? What spot welder? I just recently got a nearly new Pro-Spot. Not cheap but nothing good is.
What is the millage of the EDP coat you used? What are you going over top of it with? Epoxy?

[mepstein]

I dipped and e-coated. Sent it to pro strip indy. I’m happy with the results. Like 962 Porsche said, no process is perfect. My feeling (and the dip companies back me up) is you need to e-coat if you chemically dip. Regular, sprayed on primer, will not get back into the spot welded and folded seams. I’m no expert. It’s just what I felt was right for my car.

[rich]

Agreed on durability of EDP vs Epoxy. I never gauged the EPD as I was top coating. I used a urathane primer as the EPD is hard like Epoxy and scuffs well for adhesion. I have an old Lenco I adapted to a pinch spotter and a hand held Pinch spotter from HF.

Mercedes use to sell what was called a shroud which was the nose, both fenders and the cowl panel as one piece. I needed to build it then install it as the factory did. The butt welds were tig welded annealed and metal finished. The trough in the copper strip allowed the weld metal a place to create a strong workable joint. While the strip helped pull out the excess heat.

The factory clip I removed looked the same. You could see the pick marks where the line worker metal finshed to seam. The gaps for the hood and doors are created by filing the aluminum panels to fit with 5mm gaps. I had to create those gaps while installing the sheet metal parts. Crazy reverse process without filing gaps and no filler.

A couple more shots if your interested.

[ChrisHamilton]

Rich if you use epoxy over the EDP you won't regret it. It will make it that much more bulletproof. I got turned on to SPI Epoxy about 10 years ago and love the stuff. Sands very good as well. Many jobs I will use epoxy only. You can build with it and it stays flexible. Greatly cuts down chipping. 2015 Pebble Beach Best of Show was done with SPI epoxy and their Universal Clear.
You can find out more about SPI Epoxy (and they make several other great pr0ducts as well.)
here:
https://www.southernpolyurethanes.com/

Check out the forum as well.

Southern Polyurethanes Forum


I have no affiliation with SPI other than a satisfied customer.

[ChrisHamilton]

This is the car I referred to.

https://pebblebeachconcours.net/best-of-show/2015-best-of-show-winner/

This car was done using only SPI products including the color (ss black). I believe it set a record for the highest price paid at the time for a Pontiac GTO.

https://rmsothebys.com/en/auctions/mr10/the-milton-robson-collection/lots/r107-1969-pontiac-gto-judge-ram-air-iv/192383

Terrific products and half the price of the majors like PPG, BASF etc.

[rich]

Thanks Chris I will check it out. I am working on this factory 6 now. The car was hit in the front and poorly repaired. All the work was brazed and body filler was used like 3/4" thick. I replaced the wiper panel. It looking like it had been crushed on the driverside and burned. I dug out a big chunk of filler when the windsheild trim was supposed to rest. I wanted to have it dipped but with Covid at the time it was ready it wasn't in the cards. Had it sand blasted. Over a year later and I still have sand come out of it. I really hate sand blasting. The shell was epoxied prior to installing the NOS frnders and quarters.

[Cairo94507]

Boy...does that bring back memories.

[TB73]

Rich
You and I got the same project going ….. scary the similarities
Todd

[rich]

Let's see it Todd!