sanding gelcoat

[9rock]

Has anybody tried the 3m sanding and finishing gel coat system
I did some research on u tube and found out that gel coat can be sanded
I rounded up some materials and a hook and loop sander and did a test spot. I have to say I was very impressed with the results how fast it cut the oxidation off and small scratches , that normally take much longer to get out with heavy duty compound,

I am going to try the polishing step tomorrow
was wondering if any of you have done this


9

[Peter]

Never done it. Sounds really scary. Be very interested in how it turns out. Would also be interested to find out what type of paint you cover up the sanding scratches with.... kidding,.... good luck

[9rock]

Never done it. Sounds really scary. Be very interested in how it turns out. Would also be interested to find out what type of paint you cover up the sanding scratches with.... kidding,.... good luck

Well after watching the video and thinking about how gel coat is a solid color and not a clear coat over white it made perfect sense to me . I did leave 2 nice swirl marks but once I got the hang of it I took out a lot of scratches that simply would not come out with compound and compound is a abrasive just not as much as paper so I thought it was worth a try

9

[jimbo36]

9rock, I have restored 2 Chris Craft Commanders and used the wet sand method on the gelcoat. The key is the understanding that gelcoat is very thin, depending on the manufacturer, and can be sanded too deep. I have never used a power sander in the process. That is scary and unnecessay. I used 1000 grit wet sand paper in a bucket of water and started hand sanding followed up with 1500 grit. IT IS VERY IMPORTANT TO COMPLETELY DE-WAX THE GEL COAT FIRST, otherwise you will sand the wax into the gelcoat and the process will be compromised. This is followed with your choice of polish. I use a buffing wheel 1500 RPM. Note, polish is NOT wax. It continues cutting the gelcoat to a finer finish. This is follwed by wax. I use a buffer at a much slower 500 RPM. You can buy a combined polish & wax but I prefer to do the job separately. You need to be dilagent with continual regular waxing other wise it will oxidize quickly. One last point, be careful on edges and corners. sandpaper and polish removes gel coat much quicker on these areas. Done right, you will have a gel coat that looks like new. Jimbo36

[9rock]

9rock, I have restored 2 Chris Craft Commanders and used the wet sand method on the gel coat. The key is the understanding that gel coat is very thin, depending on the manufacturer, and can be sanded too deep. I have never used a power sander in the process. That is scary and unnecessary. I used 1000 grit wet sand paper in a bucket of water and started hand sanding followed up with 1500 grit. IT IS VERY IMPORTANT TO COMPLETELY DE-WAX THE GEL COAT FIRST, otherwise you will sand the wax into the gel coat and the process will be compromised. This is followed with your choice of polish. I use a buffing wheel 1500 RPM. Note, polish is NOT wax. It continues cutting the gelcoat to a finer finish. This is follwed by wax. I use a buffer at a much slower 500 RPM. You can buy a combined polish & wax but I prefer to do the job separately. You need to be dilagent with continual regular waxing other wise it will oxidize quickly. One last point, be careful on edges and corners. sandpaper and polish removes gel coat much quicker on these areas. Done right, you will have a gel coat that looks like new. Jimbo36

jimbo where is belleview I lived in ont 10yrs

if you look at the deep scratches you can determine how deep that gel coat is
you could sand a long time with 1200 and barley scratch the surface of gel coat its a extremely hard finish 3m starts with 400 and then to 6 or 8 .
1200 is not much if not less than heavy duty compound.
I tried the 1000 and the compound cut about the same but was harder to work with
I have gone the compounding rout on older boats before and because they had sat so long the oxidation sets into the gel coat and sometimes impossible to bring back with compound . the wax today is superior to that of just a few years ago and will protect the finish much better so hopefully this will be a one time deal

9

[Peter]

Sounds like you both know what your doing. I really though, would be uncomfortable using a power sander. BTW spent four years at CFB Trenton Ont,as a young fella, learning to be a man, and how to fix airplanes.

[9rock]

Sounds like you both know what your doing. I really though, would be uncomfortable using a power sander. BTW spent four years at CFB Trenton Ont,as a young fella, learning to be a man, and how to fix airplanes.

Well I dont know about that LOL , random orbital is pretty user friendly , the start on stop off tip is a good one ,thats how I got a couple swirl marks but that was it , but the small scratches id did real well on .

here is the video I saw that promted me

oh and ,I went up the trenten canal and my dad almost sunk our boat by tieing up to the lift lock cable
http://www.youtube.com/watch?v=UVyttTgH ... r_embedded

[Jersdevil]

My cabin and bridge was oxidized very badly. I used the hand wet sanding method with 1000 grit, then light polishing compound with polisher and then wax. The shine came back after wet sanding and after compounding and waxing it looked like a brand new boat.

[jimbo36]

9, You are right about the grit. It depands on how oxidized the gel coat is. I personally hate using compound. Too sticky and messy and wet sanding seems easy, to me anyway.

Belleville is in southeast Ontario, on the Bay of Quinte oppoosite Rochester NY. Our cruising area is Kingston and the 1000 islands.

You would not be the first to tie to the lock cable and surely not the last lol.

Peter, you probably would be amazed at the recent upgrades to the base. Building a new control tower as we speak. Of course the biggest downer in our area is the arrest of the base Commander for a double murder. Big news Internationally. Hard to imagine.Jimbo36

[Dan Faith]

A great site for this is boatersed.com forum. Look at the Marine detailing and fabrication forum Mike Ryan is a professional and under the search of articles he gives step by step on how to sand, buff and polish gelcoat. Also the grit and bonnets to use.