Just used Epoxy for the first time!

[braol]

Well, I finally did it...I got all the materials together (at the same time for a change) and went to town drilling and filling my mast step area on deck.
For thoses who don't know, my mast is unstepped and I have a Garhauer-brand base plate that I am installing under my mast step so that I can run my halyards back to the cockpit. The pre-existing holes for the step mount-bolts show signs of water intrusion, plus I just want to bed the step properly and securely. I also have one or two small areas next to the step that sound hollow when tapped with a hammer that I felt needed to be epoxy-filled.
Anyhow, I have been following the pbase.com articles reccommended by Mainesail in conjunction with the West Epoxy guides and John Cherubini Jr's "Diana-of-Burlington" blog. Everything worked as advertised, including getting the epoxy to a "mayonnaise-like consistency" with collidal silica powder. I was actually surprised how much silica it took to get the proper thickness! Initially, I thought that I had added too much at first (it was windy and a little too much was carried out of the container) but it ended-up just perfect.
The best tip is the placing of duct tape around the hole on deck to eliminate alot of clean-up afterwards. Cherubini was also right about cored fiberglass really sucking up the injected epoxy. I kept running 'downstairs' to see if epoxy was leaking out of anywhere because I must have pumped a good five or six syringes-full of epoxy into my hollow-sounding core. Nothing I could see however. I'll investigate further today before I do any more. I want to make sure I'm not just pumping epoxy into the space between the deck and the headliner. No need to waste that expensive epoxy resin! The WEST-brand measured pumps really take the guesswork out of the epoxy resin and hardener mixing and all the different additives that WEST makes for their epoxy makes using it really nice. And this is a guy that never worked with this material before. (Now, if I could only learn to weld I'd be unstoppable!)
Oh, another good tip I learned by experience: To avoid chipping gelcoat/fiberglass when enlarging a hole use a step drill (or unibit) rather than just using a larger drill bit. The step drill bit doesn't 'bite' the gelcoat like the tip of a sharp drill. That being said, a brad-point bit makes a nice NEW hole in fiberglass (make sure to run the bit backwards for a bit at first to get a good starter dimple).
Now I feel confident about spending some more time drilling and filling all the suspect areas on my deck (thankfully, not many..maybe two or three small spots near the mast step). I am also going to epoxy fill the top of my rudder near where the rudder post goes into it because I suspect that to be the source of some water intrusion. The rest of the rudder will be refoamed with two-part foam (8lb foam) and then reglassed....but I digress...
The next step will be sanding flat the epoxy, drilling and countersinking my new epoxy filled holes, and then using a combo of 3M-4200 and Butyl tape to attach/seal the mast base plate and step. Photos soon to follow! Once the step is in I only have my LED bulbs to install on my mast-mounted nav lights, hard-wiring the windvane, and a good ops check of everything to make sure it works and then up the mast goes!
Other than the expense of epoxy and supplies (metal bucket, mixing sticks, syringes, duct tape, dremel bits, etc...) actually working with the epoxy was very rewarding. And as they say, when you do it yourself the tools are free.

 

[KrustyKrab]

Nice write-up, braol. Thank you, because this is on my to-do list for off-season. Pictures would be great. And, you can also use a countersink bit to chamfer the screw holes. Mainesail's website does have great videos for deck repairs.

 

[Peninsulaman]

I concur with the quality of the write-up. We must be related as epoxy is on my bucket list AND learning how to weld. Anyway, thanks for taking the time to share this with us. Owner 1980 27.
Peninsulaman.

 

[braol]

Well, I went back to the boat and the Epoxy cured nicely (just in time for some downpours we had at the end of last week). The masking tape (used duct-tape) peeled right up leaving a clean, Epoxy-free deck. All that's left is a bit of sanding to flatten the Epoxy flush with the deck a bit and then drilling/countersinking my mounting holes for the mast step.
My only reccommendation would be to set aside extra time when doing Epoxy work in order to do multiple projects at once. This is because any mixing stick or injecting syringe that you use for your Epoxy work will NEVER work again. Cured Epoxy (especially with silica additive) is SOLID STUFF! Also, be careful to use thickened Epoxy only for deck hardware mounting reinforcement...it is better (and easier) to use "reguler strength" normal-consistency Epoxy when filling deck core because it flows much better into any voids.

 

[dtalent]

I saw this post from last year and I now seem to have the same problem with my rudder that you mentioned. Didi you ever get to repair the water intrusion at the top of the rudder where the shaft enters it? I have a Beneteau 36CC and I have 3 weeks to launch! I was thinking of trying to seal that post/rudder joint with the rudder in place. I cant remove it as the boat sits on the hard.

I ground out and filled the spider cracks in the rudder with epoxy.

any suggestions?

 

[Capt jgw]

Be sure to wear gloves when handling epoxy, and eye and dust protection when sanding. Don't get it on you or in you. Contact can cause severe dermatitis and breathing the dust can cause asthma symptoms. I do a lot of epoxy work but there are a couple of brands I can no longer use due to contact sensitivity.
Also be careful not to mix more than you can use on a short period of time, especially on hot weather. It will harden in the pot and be wasted, and can get hot enough to catch fire.

 

[rardiH36]

Braol: Enjoyed reading your epoxy recount. Epoxy is amazing stuff. Indispensable for any serious DIY boat owner.

Yes, all of us should take note of Capt jgw's safety caveats. I've read that boat repair professionals have had to abandon their livelihoods after developing epoxy sensitivity.... which can happen only after many years in the trade.

And further to the warning about too large a pot and fire. It will go into an exothermic reaction. If epoxy is mixed in too large a container and not used quick enough, the curing reaction starts to generate lots of heat and a very toxic vapor is emitted, to say nothing of the fire danger and damage to the areas being repaired. From a post I made in 2008, here is a recount of my first experience with a larger batch of epoxy than I had ever used before:


Filling the space with epoxy (I dammed the center area so the epoxy wouldn't run out) was my first newbie's experience with industrial liquid epoxy. I hadn't yet heard what could happen when mixed in large quantities. I poured a large batch into the housing and about 10 minutes later the mixture began to bubble and smoke. Fortunately only moments later it began to set up. So I turned the garden hose on to it to keep the plastic housing surface from becoming heat damaged. All ended OK, but that's the last time I'll mix a large amount of epoxy and pour thickly into a confined area.

Also on the exothermic theme. Over the last couple of years I have volunteered many days to help build a tall wooden ship. The frames (appx 40 of them) are molded into the correct shape by epoxy laminating thin fillets of dougless fir and bending around the molds to cure. We have used countless 55 gallon drums of epoxy resin and curing agent. The quantity mixed each time matches the amount the crew of 10 could apply within only a few minutes. But several times the buckets did start to flash off.

 

[braol]

I saw this post from last year and I now seem to have the same problem with my rudder that you mentioned. Didi you ever get to repair the water intrusion at the top of the rudder where the shaft enters it? I ground out and filled the spider cracks in the rudder with epoxy.
any suggestions?

The rudder repair went well. I used a small Dremel grinder to 'strip' the old paint and such from around the rudder post. We kept the rudder attached so the Dremel was the only real option...maybe a file could get in there I suppose.
I think that the fiberglass skin had ever so slightly started to get "loose" around the rudder post...not too bad considering that the boat is now 36 years old. Simply got the area roughed-up a bit and after letting some thin, unthickened epoxy soak-in, I spread some slightly thickened resin on there, barrier coat, primer, and bottom coat all applied with the tip of a small brush. I'm very happy with the repair.

For the vertical crack in the rudder skin I got out the Dremel again with the sanding drum and just went at it, grinding away a v-shaped groove into the surface of the rudder all along the crack. Then it was just a repeat of the rudder post area repair, except that I put three layers of fiberglass fabric in the crack and sanded the edges smooth.

Finally, I have now learned to weld stainless steel so now I am, indeed, unstoppable!

 

[DianaOfBurlington]

Water-in-rudder woes

At Cherubini we sort of gave up the fight of trying to keep water out of the rudder. There's just no way you'll ever win. We install a drain plug near the bottom of each rudder blade and prescribe draining it over the off-season. Also we don't provide foam cores for rudders any more. I've taken some of them apart to find the worst-smelling mold imaginable in there-- it's a stench like a sewer that'll clear the shop for an hour. What is the point?

Then again, C44 rudders are so ruggedly built that they don't need the foam. With our Hunters we can't say that; and having stainless-steel welded flags on them we'd like to keep water out as long as possible. I would recommend the drain plug, in concert with a really good routed/Dremeled groove at the top and a very well-applied and well-maintained bead of 5200 (the lesser ones like 4200 and 4000 aren't so reliable underwater).

I don't think trying to keep fiberglass up around the metal post is ever going to be a long-term solution. You just won't get the chemical adhesion, especially underwater. The same is true if you have a stainless-steel tube in the heel as well. I worked on a 1959 Swiftsure that had a bronze heel casting and a bronze rudder peg; and there was a reason they used bronze and not stainless. Just remember that, whatever the metal, DON'T paint it with bottom paint!

I filled a lot of the open pores in Diana's rudder with epoxy; and then when enlarging, for a plug, the bottom 'drain' hole (which I had drilled to see how well the epoxy saturated the degraded core) I found only solid epoxy and am not sure it's actually going to drain anything. So maybe I'll consider myself lucky that about 1-1/2" of the bottom of the rudder blade is solid epoxy and just drill a new hole a little higher!