All information and modifications on this page are provided to you for your own use. We take no responsibility for any errors or damage that may occur!!!!
GP1200R hull truing procedure 101- Compliments of Brian Stevens a.k.a. Crusty from Region 5 and Liquid Propulsion Racing...
A stand was made to hold the GPR. The stand follows the contour of the foot wells and was set up to balance the hull. The motor was removed and 5 guys were used to flip the boat from the Trailer to the stand.
This image show the hull before any sanding has occurred. There is a small section that has rubbed away from the constant loading and unloading the boat onto the trailer. This area will be filled in later.
I misted Black spray paint over the area I was focusing on truing. This helps revile the low areas after sanding.
I made a 24"x 4" sanding block for the large areas and an 18" x 2" block for the smaller ones. I used some cheep spray adhesive to attach 40 grit sand paper. I found it to be useful to have a sharp corner on one edge of the block and a somewhat rounded edge on the other. This will help sand the hull areas rolling up to the Chines.
This is a photo after the 1st sanding session. The darker areas were high spots and the areas that still have white paint are low areas. The Black spotted areas are the lowest. This show how wavy and inconstant the hull is. Be careful when sanding the chines. You do not want to remove too much material and you need to make sure that the block is flat against the surface.
These are various shot to show the sanding pattern. Always s sand front to back and not side to side. These photos give you a good idea of how much work is involved. This is why I chose 40 grit sand paper. I would say each side of the boat took 1 hour each to sand to this point.
This photo shows the hull after the last sanding session. I didn't feel comfortable sanding any more material so this is where I will stop sanding and start the filling process. Notice how most of the black spray paint is gone now.
This is the filler I am using to build up the low spots in the hull. This 3M product costs about $30. It is made specifically to repair SMC and Plastic parts. This is just my choice at this point.
These photos display the coverage of the filler. Before you mix and apply the filler be sure you read the directions for that product. This product said not to apply over painted surfaces. SO I need to remove the paint. I do so by using a loose piece of 40 grit sand paper under 1- 2 fingers to dig it out. I did so in a cross hatch patter. This helps the filler bond to the surface. Then I cleaned it with Lacquer thinner before I applied the filler. Again read your products instruction. They may differ from mine.
After the filler set up for 60 min. I sand it down with the blocks, front to back. It is easier to do it after 60 min over waiting until it fully cures. Notice the areas that were worn from the trailer loading are filled in nicely.
Well after this process is all done the hull will be painted with white primer then sanded with 60-80 grit sandpaper...
