I am getting close to glassing the inside of my Merlin. Working the wood in the narrow bow and stern is a tough go. I am not looking forward to a happy time with a full sheet of glass and trying to make the bow and stern areas pretty. I find glassing a bit stressful.

So, I am thinking of 3 lays. I would use one large center sheet and 2 smaller sheets for the bow and stern sections. The center would go down first followed by the bow and stern about 24 hours later.

I think I might try cutting the glass to shape (for the bow and stern) before I put it in (Michne's boat building page...... "The outside of the hull has been fiberglassed and sanded. It is now a perfect pattern for cutting the cloth to shape for the inside.")

I would sand the edge of the center sheet to remove resin bumps and give the glass a bit of tooth before doing the bow and stern sections. I am thinking an overlap of about an inch or so.

OPINIONS PLEASE. PRO? CON? or whatever

Well you know I'd chime in on this one. I'll give you my opinion but I hope other builders give theirs too.

I use one sheet. I can't see how more sheets would make it easier. The problem with glassing the inside is that the glass will want to pull away from the hull when you are brushing or squeeging the glass. Shorter pieces of glass won't help here. More pieces of glass means more seams, more fibers getting pulled away from the cut edges and so on. But, I learned to glass canoes using one sheet so that's what I'm used too.

If you decide to use one piece. As you mentioned, drape the cloth over the outside of the canoe. Cut it to fit on the outside allowing a few inches of extra glass at the gunwales, it will be trimmed off later. Cut the glass a bit shorted than the canoe on the ends. If the glass is too long at the ends you will have a heck of a time trying to fit it inside near the stems.

Once you turn the canoe right side up again, use clothes pins to hold the glass in place. Spend plenty of time getting the glass to fit just right before you epoxy it. Time spent here will make for a fun glassing job.

Don't let the epoxy set up too long before you squeegee. It should be a little runny so that you can pull the squeegee over the glass without it pulling away from the wood too much. The glass will most likely want to do that anyway. Just use your hand to push it back down. Remember, the less you work the cloth, the better the lay-up. Over working the glass with the brush or squeegee will introduce air into the weave clouding the glass slightly.

Relax, have fun, have a helper too if you can. It really is exciting. Don't think of it as a worrisome experience. It will turn out fine!

Tom

Tom
right........ I worry about everything
I am still cleaning the inside up. I have time to think about it.
We did a full sheet at North House and it went good. But there were also 8 students and 1 instructor to lay hands on the glass. At best I hope my son will help me. Maybe a six pack of good brew would help too ;)
Joe

I always lay multiple pieces in the inside. Overlapping about 4 inches with each. These overlaps act as ribs for additional strength. I try to lay it out so I have ribs/overlaps under each seat then there are R/O in each compartment in a tandem. for a solo lay out so you have a R/O in the middle under the center then work towards the stems. I am always doing the inside by myself so multiple pieces is easier too. The overlap can make a big impact on rigidity.
CB

quote Cedarboy: "I always lay multiple pieces in the inside. Overlapping about 4 inches with each. These overlaps act as ribs for additional strength.
CB"

He's building a solo and does not need to worry about this. I did this just once on a large 18' tandem but otherwise have never added extra glass to the inside.

Tom

I do the overlap on the solo in the middle under the seat. Regardless if it is a solo or tandem I multipiece. Got the idea from a thread from John Winters and also from the guys at Nortwest Canoe.
Not my idea but it works.
CB

I laid down a single piece of glass and worked from the center toward each end. That way I was able keep a fresh "wet edge", so to speak, as I worked my way to the ends. It will go easier than you think.
In the old days we used to glass using polyester resin and that stuff would set up much quicker than epoxy resin and it would really keep you on your toes. Polyester resin would set up almost hard within about 20 minutes and there was no more working it after that. With most epoxy resins these days you have lots of working time.

Dick

I have thought about "oil canning". Will my hull flex? I don't know, and I sure don't want it to.

It seems to me that an overlap of fabric in the middle would be a good thing....... strength wise and (especially for me) ease in construction. An overlap can't add that much weight..... can it?

I appreciate the comments. Thank You

I overlapped on my first boat because I was working alone and I also thought it would add strength. I have to admit, seeing the spots where it overlaps kind of bugs me. I only used 2 coats of epoxy, and adding a 3rd may have helped hide the overlaps. I was also not very strategic in where I placed the overlaps, and you may be able to place them better than I did. I also found that it was extremely difficult to maintain a clean edge in the process of working the epoxy across the pieces. I wound up with a few cloudy stray fibers that just seemed to replace themselves. Every time I pulled one off successfullly another seemed to pop up. I'm not sure how much strength the overlaps add or if you would benefit from it in a solo, but I would avoid them if I could just so I wouldn't have to see the overlaps every time I look at the boat. Either way though, its splitting hairs at this point and you're not going to screw up the boat at this point no matter which way you go. Nice work!

I used a single piece of fabric in my Merlin and have no oilcan problems.

JD

JD
Did you work the glass alone?

I learned something today about what a selvage edge is. I have selvage edges on my 60 inch cloth. I did a little experiment with scrap wood, scrap cloth, and epoxy.

On the selvage edge, you can sweep resin off the cloth (with brush or spreader) without the edge fraying (AMhacker, that is the fraying you described). When set-up the edge looks very nice.

I think I am now convinced that I can do a nice job with multiple sheets (selvage edges will face toward the bow and stern). I will have to overlap in the center and at both ends. I have a tendency toward over engineering. I like the thought of a double layer in the center and toward the ends. I might add a touch of weight, but.....

HighPlainsDrifter,

If you are at all concerned about working alone then by all means put in one piece of cloth at a time with the selvage edge toward the center of the boat and epoxy it in place. I would do one end at a time and when those pieces are set up but not quite hard yet you can put down the center piece and epoxy that section. You could also do this in reverse order. I believe you have a window of around 24 to 36 hours and you will still have cross linking of the epoxy resin batches. I did this on my first boat with a good result.

Dick

HPD,

I had my wife help me. We had a really tough time with the ends and with pulling the epoxy up the sides without the glass moving, but we survived.

Can you explain Selvage edges?

JD

Selvage edge is the factory finished edge on both sides of the fabric as opposed to the cut edges.

Dick

JD

As Dick said, it is a finished edge. I did not notice that my glass from Systems III had a selvage edge (even though they make a big deal of this on their WEB page). I just wanted glass that came from the same place as my resin.

The photo shows my test piece. To the right of the pen tip (and going to the bottom of the photo) you will notice that there are only vertical (very neat) strands of glass.

There is a very subtle little stitch (does not look like a weave) in the cloth at this point that ends the horizontal strands. That little stitch holds the weave in place and keeps the cloth from fraying.

Fascinating, isn't it :)

HPD how about some pictures of the inside.

Cedar

Pictures? Soon, very soon. I found the inside work to be a bit humbling.

It was a tough go. That damn flat grain accent in the bottom was a pain in the butt to handle. It had a terrible tendency to walk my tools into the relatively soft woods on each side...... I never was satisfied with the job I was doing. I am close to putting down the glass....... maybe Monday night.

I will do multiple sheets with a small (maybe 4 inches or so) overlap in center. I will then end up with a short section for the bow and stern.