Filling old boltholes-Which epoxy hardener?

[Finallybuyingaboat]

I have finished sanding the deck of my boat, now need to fill all of those screw/bolt holes. I am guessing marine bondo will not provide the strength required. As I took off an old toe rail and rub rail there are about 140 holes to fill!

My question is, can I use regular hardener? I understand I should use a syringe to fill the hole, but it seems that the regular hardener only has a pot life of about 10 minutes. I would be mixing up many, many small batches.

Also, if I used regular cure hardener, don't the syringes get jammed solid pretty quick?

I keep reading about people filling holes like these, but no specific steps outlining it. All help appreciated, especially since I just spent the entire weekend sanding down the deck some more and would like to move on to something else for a change of pace for a day or so.

[sailingdog]

It depends on whether you're going to be re-using the holes or not. If you're not re-using them... then fill them with thickened epoxy, by taping the underside and then filling them with epoxy that has been thickened with fumed silica (cabo-sil).

If you're going to be re-using them, pot the holes by reaming out the core material around the holes, and then coating it with epoxy, and then filling the holes with thickened epoxy. This will protect the core from water intrusion in the future.

How long the epoxy stays workable really depends on the temperature and the type of hardener you use.

[Finallybuyingaboat]

will not be reusing the holes , and even better I have a Shark 24, so there is no wood in the core of the deck! I am just trying to find a quick way of filling all these holes. It seems that mixing up little batches and using a syrnge would take quite a while. Yes, I know, there are no shortcuts when rebuilding a boat, but I was just hoping for a shortcut this one time!

[okawbow]

I've used Smooth-on epoxy to fill holes. It is a thickened epoxy adhesive I use to make archery bows. It has a pot life of at least 1 hour. You need a large syringe because it is thick. I used an old turkey injector. It also needs to be warm when you use it. You can buy it in pints, quarts, and gallon kits from bowmaking suppliers.

You might think about drilling the holes a little larger to get a clean, dry surface for the glue to adhere to.

[sailingdog]

Tape up the bottom of each hole, then mix up a larger batch of thickened epoxy using a slow hardener and get an empty caulking tube (west systems sells these) and fill it with the thickened epoxy, and go fill all the holes.

Originally Posted by Finallybuyingaboat

will not be reusing the holes , and even better I have a Shark 24, so there is no wood in the core of the deck! I am just trying to find a quick way of filling all these holes. It seems that mixing up little batches and using a syrnge would take quite a while. Yes, I know, there are no shortcuts when rebuilding a boat, but I was just hoping for a shortcut this one time!

[Finallybuyingaboat]

Originally Posted by sailingdog

Tape up the bottom of each hole, then mix up a larger batch of thickened epoxy using a slow hardener and get an empty caulking tube (west systems sells these) and fill it with the thickened epoxy, and go fill all the holes.

Yahoo! That will save me hours upon hours of work! Thanks!

[Fstbttms]

I've had great success using West System epoxy thickened to a peanut butter consistency with microballoons.

[sailingdog]

Glad to help. Use fumed silica to thicken the epoxy and keep the holes as close to flush as possible. Sanding epoxy sucks.

Originally Posted by Finallybuyingaboat

Yahoo! That will save me hours upon hours of work! Thanks!