I have just finished glossing my board and am not sure what sand paper grits and other materials to use to finish off the gloss coat. Do I use an electric sander to sand or just by hand? What grits work best? Thanks
Hey bwinterr, I have done a few high gloss jobs but I'm hoping a real professional answers your question. What I've done with the gloss coat is started with a razor blade on the tape line ridge around the rails then sanded them smooth by hand with a 220 grit paper. I use a machine on the deck and bottom starting with a 400 grit and finishing with 600 grit. After that I use a 3M product that is a compound/polish combination again using the machine with a polishing bonnet to buff out the product. I'm pretty happy with my results but I still see finishes on other boards that blow my mind. Good luck.
Never scrap the rails with a razor blade; this is a bad method. Use an orbital sander to do this. with a 240 grit, also by hand with 240, sand the base of the fins and other stuff like the very nose or the edges of the tail. Depends on the quality of the job, the grit of the sandpaper. In a low quality gloss, 400 grit may be not scrap the imperfections..may be you must start with 320; then 400, 500, 600, 1200, 1500, surface humidified with water; sand all the board with a waterproof orbital sander, it´s more easy than a angular sander/polisher.After that, you can made a compound with: fine polish paste, car wax and kerosene. Apply on one side a time, and with and angular polisher (makita or milwaukee brands for ex.)with a wool bonnett, work all the surface. Most with low RPM´s. After your job is done in all the board, apply car shine liquid ( it´s equivalent to a 2000 grit sandpaper); turn the tool for máx. RPM´s and rub up all the board. Finally apply car wax and polish again with máx RPM´s. after that you have got a mirror gloss finish.
Hey,reverb Thanks for the advice on the orbital sander, I've always been afraid to use my angular sander on the rails for fear of deforming. I learned the blade method through a book which suggested using a hobby planer but that didn't work real well. Through trial and error I found a simple razor blade to work decently but I still felt like it was kind of hoky. I'm also interested in the compound concoction you suggested. I gonna try going the distance with the paper too. Like I said I stopped at 600grit but next time I'm gonna take it further. Thanks again I let you know how things workout.
Scrape bead with razor blade..hand sand rail with 320 using water.Use a soft power pad on the grinder with 320 grit (keep speed slow)no water.Switch to a super soft pad (Ferro) and go over it again with 320.Finish of with 500 grit.Lastly use a wool pad on the grinder with Surleluster Rubbing Compound adding a tad of water to the board as you go.Switch to a clean wool pad (or clean the old one) and finish with a bit of water or liquid ebony.No water is use in the machining.No need to go finer than 500 or 600 grit paper as the rubbing compound will remove the scratches.This how most of the Pro Polishers I know do it (with a few twists).Takes about one hour for a longboard.A shaping type stand with a rail pocket is neede for this method. R.B.
if you stop at 600 grit, you don´t finsh with the best possible mirror gloss...
and wich type of PRO´s doing that? production PRO´s or bad ones I think..I try differents methods and if you stop at 600 or doing a gloss from a hot coat, you don´t finish with a really incredible shine gloss. I think in this type of "industry" the production ones, are not the best or talented or skilled ones..you know, see with sharp eyes the SHAPE 101 video.., 5 blanks to shape a board.. and the only one who is hand shaped ( the other are pre shaped, see the machines marks) are not the better... The backyard shaper designer and worker are the only ones with no compromise with the surf brands or stressed tours; so they (or us) could create whitout fears..
reverb: I have used the old auto-body trick of making compound from cornstarch and water. But, how do you use "kerosene" to make compound and what does it do? Also, what are the benefits of sanding above 800 grit as opposed to switching to a medium grit compound? Interesting method. Thanks for posting it. Patrick
My statements are the result of 35 years in and out of the industry and personally polishing hundreds of boards and by no means are the only way..There are lots of ways to polish a plastic surface.As for "Production Pros" go I challenge you to do a better job than the pro polishers in Melbourne Florida that taught me this sytem.If you know what you are doing with soft pads and Sureluster Compound you will achieve good results.Sure you can go through the grades of paper up to Micro and use ten different compounds if you want but it will look no different.Machine polishing in itself actually degrades the durability of the finish.When you cut the wax off of Polyester Gloss Coats you make it more prone to scratching etc.Fiberglass boat hulls have a wax surface that is picked up from the mold..cut the wax and watch what happens.Keep on shining. R. B.
Patrick, the kerosene is mostly abrasive and it´s ideal to utilice like vehicle for the pastes..he sand the scratches a lot. It is in the surfboard industry for years (the surfboard industry is not only in Usa) Cleanlines, yes, it´s really true that wax off the surface debilite it..but above 1000 grit, the remove of it is uneven; also it´s only one sanding from tail to nose with each grit.. the 1500 and 2000 grit or liquid equivalent, are used extensive in platery and jewerly for obtain mirror like finish.. if the job is not good enough, so "x" people start the work with 280 grit or something like that, in my opinnion it´s better to sand/polish to 1500.., with 1200, 1500 or 2000 (or eq.), it´s like clean the surface but if you do it that way for 35 years, for you and why not, for me , it´s ok. but in several countries the finish men use this method, and work ok too. also i think that is more easy for the initiate to finish the surface well
to get the tape line down the best thing is an auto body file, available at auto parts stores. they look like they will eat your board but are very smooth. they are expensive so it may be cost prohibitive unless you lots of boards. i used one for many years in my shop and had very few burns. after you gloss one side and pull the tape, use a blade to feather that tape line into the board and then mask off the other side. the tape line is then much smoother to begin with and easier to manage. good luck.