Wet sanding primer

[freedre]

I am about to tackle my new boat, a 1996 Bayliner Cierra 2655. Basically, it is in pretty good shape, but I want to polish and seal it.



My question regarding wet sanding is how to go about it; is this a process done with a PC (I have one - quite a bit of car detailing experience) or is it a hand only chore? I don`t expect to do the entire boat, just the badly oxidized patches.



Any assistance will be greatly appreciated,



Thanks in advance

[MorBid]

I wouldn`t use a PC for Wetsanding anything, but there are Air Powered DA sanders made for the purpose.



I always advise folks before they take up this task to understand the objective when wetsanding as it`s quite easy to "cut" through to the under lying substrate which will require the re-application of the material that was being sanded (in the case of Clear Coat that would be a PITA).



That objective is to just make the material (in your case Primer) smooth.



You`ll need a bucket of water (with a couple of drops of Dish Soap added for lube, just a smidgen your not washing anything with it).



Primer is sanded wet with P600 Grit Wet/dry Sandpaper so you`ll need some of that in addition to something to wrap the paper around. I use either a 3M Wetordry Rubber Squeegee or a Motor Guard Memory Block MB-1. Others just use a flat piece of wood that is of sufficient length.



Having a water source like a garden hose around helps to wash down the surface between attempts so your flushing the "sludge" away as you work.



Let the paper soak in the water/soap mix over night or at least several hours prior to use to soften it up. As usual make sure the surface is clean so you don`t get something caught in between the paper and the surface causing scratches.



Now that you`ve got everything set up it`s time to go to it. Wet down the panel and wrap the sandpaper around the squeegee or block taking care you don`t leave any hard edges exposed. Now just start sanding. Work sections at a time.



The key here is to remember your "wet" sanding so the paper and the surface needs to stay, well, wet. So keep dipping the paper back into the bucket of water and make sure your rinsing away the sludge buildup. You don`t have to un-wrap it each time.



At first you`ll feel the paper "grabbing" into the surface. This is the friction between the uneven material on the surface and the sandpaper. As you continue the resistance will lessen. Check your progress often. This is where having a squeegee comes in handy cause you can just use it to clear the water and sludge off the surface.



The Primer should have a smooth feel to it and no texture. It will actually begin to develop a shine or gloss. That means your done. Once the entire panel is finished, wash it down the way you would normally using a PH Balanced Car soap (don`t use anything like the "wash and wax" type stuff is it could leave contaminates that will interfere with the painting process.



Remember when wetsanding Primer you only want to remove the texture and that`s it. People can and have sanded too much and went right through the Primer or Clear Coat. Which as I mentioned earlier means you`ll have to clean everything up get it dry and re-apply more material to the area where the "cut through" is.



HTH



Greg

[freedre]

Thank you Greg - this is exactly the info I was looking for.



I `mis-spoke` my subject line. When I mentioned "Primer" I was alluding to "beginners lessons" on the subject and not actually `primer` the paint.



I will be working on my new boat, which for the most part is in pretty good condition, but I want to be able to buff up a few problem areas. I am going to give it a go with your excellent guidance.



Thanks again

[MorBid]

Sorry for missing that. So your probably looking to take some Orange Peel (OP) out of the finish. Principles and techniques are the same, as you mentioned.



But you`ll as you work on the surface and begin checking it you`ll see some spots that look sanded (the high spots) and some spots will still look shiny or have gloss (low spots) when to stop here is when the area has a even sanded appearance.



Again be careful not to go down too far or you`ll break through and the Clear won`t buff back up.



There is a nice how-to (with pics yet) over on the Autobody Store Boards that covers this topic.



Greg