Will Plastic Glue Adhere to Epoxy?

[Ken_StJohn]

I had to fill a seam which opened on the dead wood to keel joint on my Weekender. Although taped off, some epoxy found its way inside the stem notch cut for the bottom panel. I was going to use the standard plastic resin glue for gluing the bottom panel to the keel but, I am concerned about the square inch or so that has epoxy on it.

Today's the day to go 3-D. I didn't want to epoxy the keel as I have no filler available. Will the plastic resin glue adhere to the epoxy or am I stuck with having to epoxy the whole thing? Does sanding the epoxy'd area and using the glue seem a reasonable alternative?

[Greg Luckett]

I am not sure about your question, but I would not chance it. If it were me, I would invest in some good epoxy and filler and do the job the best way I know of. Why take a chance on that seam expanding or filling with water and then the ensuing large cost repair later on? You can make filler from fine sanding dust from the same sort of wood and it will match better too.

Greg.

[Ken_StJohn]

Greg:

Yeah, that is the prime objective regardless. I will delay the event to do it right. I just wanted to see if anyone knows for sure before I launch into something I didn't have to do.

While we're on the subject, if I have to go with filled epoxy, how do I determine how much to add??

[Greg Luckett]

I add a little bit and stir then add more until it is like peanut butter. I suggest you have some little sticks to push the stuff deep into the cracks which will help displace the air, if possible, otherwise just use a good putty knife for forcing it into the crack. Oh, and before that, put in just the epoxy without thickener, as deep as you can. I often use a small syringe (if I remember to get them).

You will find that even if you only need a small amount for this job, that epoxy is handy stuff for lots of jobs and you will not waste it. I use to buy just the pint size West Systems, but now I buy it by the gallon, and I like the pumps. They are fast and I make up lots of small batches when I am working. Oh, one other thing, make sure you protect your skin and eyes. I use Nitrile gloves, and plastic safety glasses.

Hope this helps.

[Ken_StJohn]

Greg:

Yes, this helps a lot! I got some basics from Adla the other day and am using West 105/206. I have the syringes and the sticks so I'm all set. The pumps were out of stock so I bought small graduated mixing cups. Don't have any cracks to fill since the epoxy filled the ones that were there!

Learned about the amount of heat contained epoxy generates yesterday. Had to use pliers to get the cup out of the garage after I noticed the smoke billowing out of the cup!

My local <50 mile round trip> West store was kind enough to eat the overnight shipping to send the pumps directly to my house. So I intend to use them as much as possible to repay their customer service. In the mean time I'll have to mix by the cups which is kind of scary from a flame up stand point! I'll need quite a bit to do the whole keel to bottom joint and am concerned about this much in a cup.

I'm guessing I don't have to put epoxy on both surfaces, right??

[Barry Pyeatt]

To answer your first question. Epoxy will repair over most anything. The Plastic resin glue will not adhere well to epoxy.

Now to your particularly situation. The small area where you have epoxy on the surface can be sanded off. The plastic resin glue will do a good job of adhereing for the entire area. And it isn't as prone to having issues with starvation from too little being in the joint as epoxy does on occasion with too much squeeze out.

You should coat both surfaces with adhesive on this joint. Then when you try to pull it down to mate there will be enough contact to bond well. The plastic resin glue will bond well even if starved a bit. And give you a much longer working time. Unfortunately epoxy doesn't like to be squeezed out leaving a starved joint which is weak. The forward curve of the bottom has some real resistance to being pulled down to mate with the keel. You may need to use fender washers on larger screws to help pull it down tight and then replace them after the glue sets.

You can still create your fillets with wood flour and epoxy over the cured plastic resin glue and they will hold up just fine.

Tip on mixing epoxy in larger amounts. After mixing it up, pour it out into a larger, wider container so that it has more surface area to disperse the heat. It will slow down the cure time and keep from overheating. It will give you longer to work with the resin in applying it. Often a paint tray with a disposible liner will work well for larger quantities.

[Ken_StJohn]

Barry:

Thanks for the excellent information, particularly re the larger container. That was pretty scary yesterday.

Also, the fender washers are a great idea. The plans call for screws every 5-inches alternating sides out from the center line. Any opinion on this spacing/method?

[Barry Pyeatt]

No, the spacing is fine but it may be hard to pull down at the front end of the bottom. I had three or four screws pop their heads off before I got 1/4" lag screws and fender washers inplace and tightened down. If I had been using epoxy, it would have set up before I was able to pull the bottom down to the keel. But once I had it down and placed the regular 1 1/2" X 8 screws in tight with I think three lag screws down the center, it held fine. Once it set up over night I pulled the lag screws and ground off the remaining stubs of the screws that had broken along with pulling two broken off drill bits. Then just filled the holes with epoxy and everything went along normally until the next minor crisis. :roll: 8)

Front bulkhead! Really get this one right as far as the angle to bottom and its measurement at the front of the mast box, not the front edge of the bulkhead. This is probably the only really critical angle on the entire boat at this stage.

[Ken_StJohn]

Barry:

Yep, thanks to the inputs on the mast box jig from Dave Richards, I'm ready for that one!

Roger on the screw heads popping. Would have probably found out the hard way. That's the truly great part about this Forum! When I first began the process I was concerned about the lack of contacts in Colorado according to the Stevens' website. Don't worry about that any more - the world is my oyster (with due apologies to Oyster!).

[Andrew_Butchart]

One of the (many) things I did different during assembly was to put the keel on the bottom upside down. The weight of my plywood keel caused the bottom to curve quite well to the keel. I also put the transom on before putting the keel in place.

One of the bigger challenges with this task was doing it on my own. I used lots of rope and a bit of patience and also managed to get my daughter's help to align the stern post with the transom.

[Charlie Jones]

another tip on slowing down epoxy on a very hot day. Use two paint roller trays. Put some ice in the lower one, then set the next one inside, on the ice. It'll keep the epoxy cool and prolong it quite a bit. I've used the technique in glassing and rolling fill coats in over 100 degree weather, when nothing else worked.

And don't think that smoking epoxy is just an annoyance. A friend on the TSBB burned his boat down when a batch over heated inside and caught a roll of paper towels on fire. Totaled the boat.

The REAL key is smaller batches though.

[Greg Luckett]

It is nice to have more than one person helping during a large job. Several people mixing up small batches and doing a "bucket brigade" sort of thing. The first time this happened for me, spoiled me, since I had always worked alone before that. Two people could do a lot of work in a short time.

Charlie, I like that ice cooling trick, even if it is so rarely needed up here in Michigan. Maybe I could mix larger batches and speed up the process? I really hate it when I create a smoking mess and lose the materials. My neighbors were alarmed the first time I ran out of the shop and threw a smoking can into a snow bank....and it kept smoking...lol. Then another time my foam rollers soaked up too much and began to smoke too. I learned the hard way that small batches are a lot more forgiving.

[Ken_StJohn]

Well, another successful operation assisted in its success by you guys! I took the time to come up with a press in anticipation of having to persuade the bottom down flush on the keel-as you guys pointed out. Had some lags ready too but, didn't need them.

I was succesful in cleaning out the epoxy with a sharp chisel followed by sanding as suggested above.

I took a 6-inch piece of 4x4 and set it on end on the center line just in front of the next screw. I put a 2x4 across it going side to side. It was long enough to extend beyond the sides of the trolley. I put a pipe clamp on either end from the 2x4 down to the bottom of the side rail of the trolley and tighted until the bottom pulled down tight on the keel. Then drove the screw and moved on to the next one. Worked great - we're now 3-D! Thanks, guys!

[Ken_Potts]

I like the clamping solution Ken - I'm going to remember that one.

I'm all about creative clamping.

And congratulations!