Star 45

Star 45

Tuesday, September 09, 2008

fiberlass notes

From: Dave Mainwaring
Date: Mon, 29 Jan 2007 18:06:15 -0500
Subject: Re: [Star45] Re: Construction question

so it can be sanded easily and keep the weight down.

Depending on the size of the gaps a couple of choices would be:
automotive spot putty is good, not bothered by epoxy or poly and sandable.
Another would be using automotive "Bondo" putty which is a resin with filler used for autobody work.

Micro and macro balloons both glass and phenolic mixed in resin are good also. Balloons may be difficult to find and they are a little like working with talcum powder, stuff is so light it flies around:)

I've used a lot of spot putty over the years you can get the stuff at any auto parts store that sells touch up paint. I still use it around the house for filling nicks in painted surfaces that get scratched. I think it is acrylic based, smells like acrylic lacquer.

I also have used a lot of Bondo over the years since it strong (hardens like a rock) and can be used to fillet pieces of wood in place. Mix a lump of Bondo with a smidge of Bondo hardener, use your finger to run a bead down along side the joint and in minutes it is ready to sand and paint if outside the hull.

Long and uneven gaps on a 45 inch model can't call for a lot of filler.

I've know big boat builders who make resin-foam blocks using pasta :) to add air in the resin to fill floatation areas.

If you have large gaps (1/8 inch or more) then that is another issue. You can also use a can of spray-in foam from Home Depot if you have serious gaps and then scrape off the hardened foam when the crack is filled. Hopefully the workmanship has left not been that .....

Seriously, how much weight can a crack filler add to the hull's weight?

Uncle D.