PDA

View Full Version : Blotchy finish


Rich J
03-25-2014, 08:30 AM
I have an older Silverton 34C, the hull looks great, no oxidation or dull spots what so ever however the topside (house and bridge) is a different story, depending on the angle you look at it you can see blotchy areas (almost like previous wax products have dried) it's been like this since I purchased the boat, I've tried several compounds with both a rotary Makita buffer and wool pads, a porter cable 7424 with foam pads and the results have been less that satisfactory, still the blotchy areas remain. Lately I've used Presta's Ultra cutting compound then Presta's Ultra finishing polish (both by wheel) then finally Collinite's paste fleet wax by hand, any thoughts or recommendations on how to rid myself of these problem areas?

Mike Phillips
03-28-2014, 08:33 AM
I have an older Silverton 34C, the hull looks great, no oxidation or dull spots what so ever however the topside (house and bridge) is a different story, depending on the angle you look at it you can see blotchy areas (almost like previous wax products have dried) it's been like this since I purchased the boat,



Look anything like this?


http://www.marine31online.com/gallery/data/510/Silverton_34C_001.jpg




I've tried several compounds with both a rotary Makita buffer and wool pads



Gel-coats historically love compounds with wool pads on rotary buffers. This combo will chew threw any oxidation and leave the surface very glossy and shiny. There will be swirls or hash marks from the abrasives and the individual fibers that make up a wool pad but nevertheless, the surface will be clear and shiny.

If this combo isn't creating a high shine or high gloss finish to these dull spots that's a red flag.





Lately I've used Presta's Ultra cutting compound then Presta's Ultra finishing polish (both by wheel) then finally Collinite's paste fleet wax by hand,

any thoughts or recommendations on how to rid myself of these problem areas?




I've never used any of the Presta products. I've known about them for years just never used them. In a couple weeks I'll be doing some work at a shop that used to use them and I'll see if I can get a bottle or two just to test out.

Besides that, kind of off the cuff, do you know 100% for sure the house and bridge don't have a painted surface like Awlgrip?

It just doesn't make sense that the hull will polish out but the topside won't unless there's something very different in the surface/surface coating.

It is possible that a higher quality, or at least a different abrasive technology could make a difference in the buffing results, but the only way to find out would be to do some testing.

Sometimes, a real simple approach can work like taking a light cutting cleaner wax with a wool "finishing" or "polishing" pad, (not an aggressive cutting pad), and re-buff the area at a medium speed with your rotary buffer.

That's what I would try next...


:)

Rich J
03-29-2014, 07:30 AM
thanks for the reply,,,I'm sure that the topsides and bridge haven't been painted, it's gelcoat. it seems that the previous owner allowed whatever product to dry (at least that's what it looks like) I've tried several products and the latest has been the Presta line and honestly It has gotten better but not where I believe it should/ could be....I'm almost to the point of wet sanding the bridge and starting over....the difference between the bridge and hull I feel is direct sunlight, the hull you can almost wax in shade where the bridge is direct almost all day. I'm going to try marine 31 this year and see where it goes....thanks

Mike Phillips
03-31-2014, 01:59 PM
the difference between the bridge and hull I feel is direct sunlight




The sun is the culprit when it comes to horizontal surfaces, especially boats in th water.

Just take a look at what it can do to unprotected skin in a single day and then multiple that by a 1000 times or more...


Take a look at the Marine 31 Gel Coat Heavy Cut Cleaner Wax. This product cuts fast, polishes and leaves the surface protected in one step and actually works really well..


Marine 31 Gel Coat Heavy Cut Cleaner Wax (http://www.marine31.com/m31-241.html)



:)