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RE: Undercoat or paint

HarperLaw — Sat, 17 Mar 2012 00:56:02 GMT

Undercoat is quite hard to do but it acts as a cushion against knocks and if you don't undercoat you will likely find the next time you come to paint the old paint peels off rather than rubs down. So it is must.

RE: Undercoat or paint

jake1313 — Tue, 21 Feb 2012 10:04:30 GMT

There is no "easy" way. I have done several of these and usually find rust under the undercoat in the seams etc so it is best to take care of it now rather than have it appear later. Laying on your back doing it will be even harder. I use a auto rotisserie. There are sevral out there but since I do restos for a living I got the roto 2000. www.theroto2000.com

It is well worth the investment and you can sell it when you are done with it.

RE: Undercoat or paint

miloacademy — Sat, 17 Dec 2011 15:54:49 GMT

Undercoat is any coating applied to a surface after priming and before the finish coat. It is matt with a high content of pigment and extender and a color approaching or helping that of the finish coat. Undercoats have many functions, they increase the thickness of the overall film, they hide the color of the primer or the previous layer on the existing substrate, and they are generally tinted in a similar color range as the topcoat. Varnish undercoats have less oil per unit of resin than varnish finishes.

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Undercoat or paint

Denis Pele — Sun, 06 Mar 2011 17:05:33 GMT

Doing a partial frame on restoration on the rear underside on an MGA. The suspension, gas tank, everything has been removed from under the rear of the car. I have painted all the suspension, axle components with KBS black rust encapsulating paint (similar to POR15). I will also be painting the frame rails with this paint.

My questions are what to do with the underside of the body. It had been undercoated with a tar based product at some time and it did its job since I only have to weld in a 6" X 2" patch in the trunk. the undercoating was starting to crack so I removed it as good as I can with heat and scraping.

1) easy method: Clean up only the surface rust spots and spot paint them and the new patch with KBS paint. Then reapply undercoating over entire surface. What type of undercoating is best? Has anyone used WAXOYL?

2) harder method: Remove all of the tar undercoating with aircraft paint remover (recommended by KBS). Then prep and paint the surface with KBS.

I would like to here of other ideas that would last for a long time and prevent rust. This is not a show car I just want to get her back on the road to enjoy. src="http://board.autorestorermagazine.com/Skins/Auto/Images/EmotIcons/BigGrin.gif" width=20 height=20>