How about this for an original undercoating texture match?

DarrylD · 03-24-2006, 05:59 PM

I've been experimenting with techniques and products for recreating the original thickness and splatter pattern of the factory applied undercoating.

What do you think?

BEFORE:

AFTER:

goldsc78258 · 03-24-2006, 06:06 PM

Great! what is the method? I'm going thru a repair like that and was wondering about the undercoating finish

livi · 03-24-2006, 06:34 PM

Yup, you ARE truly a handy man, Darryl!

bell · bell's Garage

this thread is worthless without an explanation of the process

nice work

DarrylD · 03-24-2006, 09:22 PM

Ok, here's how I did it. You are going to laugh at how "low tech" it turns out to be.

The Wurth high-build underseal just doesn't have the splatter size of the original, so a random "texture" needs to be established on the smooth steel first and the texturing material used must be flexible, stick well and be paintable. I figured that 3M™ Ultrapro™ Autobody Sealant (stock #08300) would work perfectly so I dabbed it on by fingertip in a random pattern and "drop" size.

After it dried over night, I sprayed two heavy coats of Wurth high-build undercoat over it. As you can see in the "AFTER" picture above, heavy droplets of Wurth undercoat formed on the rough texture and it looks just like they were splattered on.

Obviously a very labor intensive way to match the undercoat but ideal for the patchwork I'm doing in my wheel wells. I'll have to try something else on the floor pan but in that case I have gravity working with me to allow the spatter drops to hang like stalactites instead of run like they do on vertical surfaces.

Dan in Pasadena · Dan in Pasadena's Garage

Excellent work Daryl.

DarrylD · 03-25-2006, 09:16 PM

Thanks Dan!

It may seem a bit compulsive but this area of the rear wheelhouse is some of the most visible undercoating on the car.

304065 · 03-26-2006, 06:13 AM

Nice Darryl! . . . soon you will be wondering where to find original KAMAX headmarks for the bolts that hold the spring plate cover on, and then wondering where to have them re-plated the original clear zinc, and to what thickness!

Go for it man! Your restoration is inspiring, so much so that I think your motto should be "It's only original TWICE!"