Dry Method Or Wet Method-----Which Do You Prefer

[Bill Matuscak]

I've got the transom wood and most of the floor wood installed in my project. I'm about ready to apply the fiberglass mat on both. I have a copy of Runabout Renovation and Fiberglass Boat Repair & Maintenance by West Systems. Between those books and reading this forum faithfully, I've progressed well.<br /> I'm using polyester resin and 1 1/2oz. mat. Here's my question. The author of Runabout Renovation always wets the wood with resin, then lays the mat and adds more resin to saturate the mat. The West System book talks of the Dry Method where you lay the mat on dry wood, then soak the mat with resin. They also mention the Wet Method (same as Runabout Renovation) but state it is NOT the prefered method.<br /> Which method have you folks used on your projects and what do you think works best? Also, the polyester resin is very thin. When you covered your transoms with mat or cloth how did you keep the resin and mat from sliding down and pooling in the boat bottom before is set? Should I staple the mat to the transom to prevent slippage?

 

[Indymike]

Re: Dry Method Or Wet Method-----Which Do You Prefer

In the West book they still wet out the subsrate (wets the wood with resin) first don't they.<br /><br />Been doing some reading too. Have a project myself.<br /><br />Mike

 

[G DANE]

Re: Dry Method Or Wet Method-----Which Do You Prefer

Just Bill<br /><br />I f you wet the plywood first, then lay the mat and wet it again, you will get the plywood ot absorb as much poly as possible. The mat will stay on the wood, dont worry, it evendoes, upside down. If you work on larges areas, use a little laquer roller, this will give the nicest surface.

 

[Bill Matuscak]

Re: Dry Method Or Wet Method-----Which Do You Prefer

For Indymike: West says to prep the wood (sand and clean) position the cloth over the surface, pour a small pool of resin in the center of the cloth and work it to the outsides with a roller. They say if you're working on a sloped or vertical surface to hold the cloth in place with masking tape or staples.

 

[petrolhead]

Re: Dry Method Or Wet Method-----Which Do You Prefer

I prefer the dry method and always use it. I seal the wood with resin first, let it cure and then apply the glasscloth, this has to be done soon after the seal coat has cured or you have to remove the amine blush first.<br />Whenever I've done it without sealing the wood first I've had problems with bubbles under the glass, the bubbles are air being released from the timber itself.

 

[lark2004]

Re: Dry Method Or Wet Method-----Which Do You Prefer

preferably, coat the timber in the afternoon, as the temperature is falling (put the timber outside in full sunlight for a few hours, then bring into shade and wait 15 minutes before applying resin) what this does is actually draw the resin into the timber. The bubbles petrolhead mentioned are known as out-gassing. As the timber warms up, the air inside the pores of the timber expand and vent out to the atmosphere. As the timber cools down, the oposite happens, If the pores are covered with resin, then it will be drawn into the timber and will result in a much stronger bond. (Extreamly important if you are going to use poly resin!) N.B. If you live where it is snowing or very cold outside, Then you will need to find some other way of warming up the timber!

 

[crab bait]

Re: Dry Method Or Wet Method-----Which Do You Prefer

what PETRO & LARK said.. a base & sanded coat on the wood is nessisary.. keeps resin from soakin' in.. an prevents gassin' ,,which it now can't/wont,, because it's now sealed..<br /><br />masking tape works well to hold down.. just remember to leave 'folded over' tape pull tabs as to remove as you go..<br /><br />believe me,, after you apply some resin,, nuthin' gonna move or slide.. since the mess is so sticky.. the tape is just to hold it in place so to start..

 

[JasonJ]

Re: Dry Method Or Wet Method-----Which Do You Prefer

Personaly, I like the wet method. I liberally coated my wood with resin, layed the mat, applied more resin. My thought (as I am no expert) is that it is better to have the mat, resin, and wood become a single unit (or as single as it can be) rather than have layers joined to layers. If the proper amount of resin is used, it saturates fairly deep into the wood without wicking too much from the mat, causing it to be dry (probably why wet method is not recommended). That sounds better than applying to wood, letting it cure, sanding, then applying another layer with fiberglass. Seems like too many mechanical bonds to me, but I have the nagging feeling it all works just fine in the end whichever way you go.

 

[Solittle]

Re: Dry Method Or Wet Method-----Which Do You Prefer

Make sure that you cut the glass before you mix the resin. Mix only as much resin as you can apply quickly as resin becomes useless once it starts to gell. I use the wet method & mix not more than a quart or two of resin at a time.

 

[Bill Matuscak]

Re: Dry Method Or Wet Method-----Which Do You Prefer

Thanks Guys. Your comments really help. I'm ready to plunge ahead.

 

[thejeepster02]

Re: Dry Method Or Wet Method-----Which Do You Prefer

I go with the wet method, but make sure you dont mix it to hot. the longer it takes to cure, the more time it has to soak into the wood.<br /><br />also gives you time to roll out those air bubbles