Re-using transom holes

[marc00]

I'm about to replace a transducer mounted on the back of my 75 SF 20 and I'm wondering if you guys could help me figure out the right approach. The good news is, I can re-use the existing screw holes but they are filled with some sealing material that I'm planning to drill out before putting new screws in the same holes along with some marine tex. Is this the best approach?

[gw204]

You're close. Drill out the holes as you said until you get good, clean wood. I like to put a little countersink on the hole as well. Using a small paint brush/old toothbrush/etc. give the wood core and exposed glass a few coats of unthickened epoxy allowing the epoxy to soak into the wood between coats (I'm usually too impatient to wait more than a few minutes though). Then inject thickened epoxy into the hole with a small syringe and allow it to cure. Once cured, sand flush redrill your screw holes and seal with your favorite caulking.

In order to keep runs, drips and sanding to a minimum, once the hole is drilled I completely tape over it using blue painters tape. Then I cut a hole in the tape about 1/16" larger than the counter sink. After injecting the epoxy, I'll place another piece of tape over the hole and apply light pressure to it until it's almost flush with the surrounding surface. When it's cured, I just pull the top layer of tape off, sand it down down to the first layer of tape, pull that tape and then fine tune it to get rid of the tiny edge that might be left.

[marc00]

A couple questions:

1) If I'm reading you right it sounds like I should redrill the holes a little deeper and thicker than what's there now so I can hit clean wood and create some solid epoxy for the new pilot holes. Considering I have 4mm holes now would you go with 5 or 6mm holes?

2) Where is a good place to order glass supplies?

Thanks for your help. This is my first time at this and my transom is original so i want to make sure it's done right.

[DonV]

Start here......

http://www.westsystem.com/ss/bonding-hardware/

[Blue_Heron]

A couple questions:

1) If I'm reading you right it sounds like I should redrill the holes a little deeper and thicker than what's there now so I can hit clean wood and create some solid epoxy for the new pilot holes. Considering I have 4mm holes now would you go with 5 or 6mm holes?

2) Where is a good place to order glass supplies?

Thanks for your help. This is my first time at this and my transom is original so i want to make sure it's done right.

Marc,
Question 1 - The idea is to isolate your fastener hole from the wood core with an epoxy plug that will bond well to the transom core. The diameter is going to be driven by the size of the fastener, but also by what size hole you can successfully fill with thickened epoxy. Anything smaller than 3/8" is going to be tough to fill.

Question 2 - If you go to your "My Home" page and fill out your profile, we'll know where you are and it will be easier to answer questions like this. The answer is different for someone in Cape Cod than it is for someone in West Palm Beach. I'm in Florida and get most of my stuff from US Composites. I don't know the best source in the northeast.

Good luck,
Dave

[marc00]

I noticed the West System link talks about inserting the screws into the thickened epoxy before it cures. What are the advantages/disadvantages to this method?