Undercoating after repair

[rich roush]

I would appreciate all the tricks known by the group to best reproduce the original undercoating texture etc. after small repair next to battery box.
Thanks

[EsGeht]

Most have used Wurth "Stoneguard" or Wurth "SKS" It must be sprayed with a special gun (not expensive, but you need a compressor) which screws onto the plastic bottle this stuff comes in. It builds up to a heavy, bubbly appearance like the original, if sprayed properly. It is available from Stoddard and other vendors, or directly from Wurth at wurthusa.com.

[Cornpanzer]

If you are doing a small area, you can get the Wurth in a spray bomb. Use some etching primer and then hit it with the Wurth.

[preS]

I am currently spending my days w/ scraping my floorpan and what is close to it. I have learned that Wurth like paint breaths. My question is, can/ should a product like POR15 be used before applying Wurth stoneguard?

Any comments from experience are appreciated.

Thanks,

Richard

[edmayo]

Before undercoating prepare the area with Wurth metal prep, basically it is a mild acid wash, the inexpensive undercoat guns will get the job done, but you will have to experiment with air pressure and nozzle setting. I have found it difficult to really perfectly match what the factory did, but you can get very close. Use the waterbased Wurth undercoat, the solvent based is too difficult to clean from the gun. Be sure to thoroughly mix before spraying, it will settle in the bottle. Try a test area and it dry, as it will flow out some as it drys, and that will determine what settings you need to use as you spray it on. Even though it says you can paint directly over the undercoat, I have found it best to spray a primer sealer on first. DON"T attempt to put on real thick, it will never dry, if need be let it dry for a day or two and then apply a second coat if necessary.

[Zithlord]

When removing a small area of rust in the front luggage compartment I used metal ready from por-15, then por-15, then epoxy primer, then undercoating from Hagmans Carosol (body spray), then a new layer of epoxy primer and then body colour. It is impossible to see any difference between the repaired area and the original surrounding area. The texture is exactly the same. I had to spray a pretty thick coat of the undercoating stuff to get the right texture, and used a work lamp, heating the area, for it to dry.

John