Fiberglassing bow and stern Keel angles

S

stephen thompson

New member
What's the best way to lay 4 inch wide glass over the angle of the keel.Should I do it in two pieces and overlap them in the center of the keel or use small pieces over lapping them as I go down the keel or use one big piece and make little slits on each side and overlap them as I go over the curvature/angle of the keel.
Thanks, Steve
 
Good morning, Steve~

A few questions:

Primary purpose ? Are you repairing the keel or adding protection?

What is the hull material? Are you going over wood, 'glass, aluminum ?

Are you using 'glass cloth or tape ?

Epoxy resin ?

BTW: Those little slits you need to cut in fabric when following a curve are called darts.

All the best,

SJS
 
All depends on the keel shape. Shallow rounded keel, tall skinny, glass or wood boat? Pic would help...
West System had a tech line. Was glueing up a iceboat plank and they helped me a ton. Steve Sanford has done a few...
 
im repairing a carstens mallard fiberglass duck boat. the keel is beat up and im using epoxy and fiberglass cloth. the bow and stern has a very gradual rise but if i try to lay the cloth in one piece it will bunch up. im thinking i should (Dart it) thanks Steve. But it may be easier to do it in small or short pieces or over lap in the center? this repair is for adding wear protection.
 
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Good morning, Steve~

I would cut "tapes" out of cloth and run them as long as possible. I would use 2 layers in one of 2 approaches.

Overlap: Use 2 widths, say 3 and 5 or 2 and 4. Apply the narrower one first, then apply the wider.

Stagger: Use the same width but apply each off-center.


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Wherever you need to cut darts on bends, be sure to stagger the darts between the bottom layer and the top layer.


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I would also run cellophane tape an inch or so wide of the 'glass - to make the job neater. You will want to wipe any runs as it cures - visiting the job every hour or so with a rag after you apply the resin.

It would be helpful to add some Cabosil (fumed silica) to the resin to minimize running and to toughen the the cured resin a bit.

To prep keel, I would use 40 or 60 grit then wipe with acetone.

Finally, after the job is fully cured, I would wipe with warm water to remove any amine blush. Then, sand with 80 or 100 grit and apply at least 2 coats of paint to protect from UV.

Hope this helps!

SJS

 
I use Steve's stagger system. Had a Boston Whaler for commercial fishing and worn out the bow from the flats. Redid it every 4-5 years.
A little sand paper and like new.
 
Thank you Steve and all. I appreciate the time of putting drawings in for me.their self-explanatory. I can see it clearly now. A couple more questions if I may. What is the difference in cellophane tape versus blue painters tape which is what I was going to use ? I read through the devlin duck boat build article on this form. The gentlemen used an Epoxy primer before he painted his boat. Do you have to do that when painting over epoxy ? I'll be painting with Parker's duck boat paint shot through a gun.
Thanks,
Steve
 
Steve~

The benefit of cellophane is that the resin - epoxy or polyester - will not stick to it. This is a problem only if the resin is heavy and cures on the masking tape. If you will be monitoring the cure, you can wipe the resin so it is thin right near the tape. In practice, I use whatever is handy at the time.

Regarding the paint over cured epoxy. I have read Devlin about some of the problems he has encountered. I have not experienced them and have had good luck with duckboat paint - because it's a flat oil - right over the washed and sanded epoxy.

All the best,

SJS
 
Ha Ha yes it is Rich. That 16 oz. pepper steak and two Margaritas still taste as good as when you were there last. I think ill use the cellophane tape as this is my first fiberglass repair. thanks again for the help.
later,
steve
 
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