Bad scarf

This is what a bad scarf looks like. That lip is about 1/8" tall and the gap extends 1 1/4" into the scarf. My first scarfs had a small gap, but this was unacceptable. I am unwilling to put myself into a dry boat that has only 2/3 of a 1/4" plywood bottom scarf. Too much potential for wetness. Actually, I considered just packing the gap with epoxy and forgetting about it. The outside gets another coat of epoxy and fiberglass and the inside gets at least one more coat of epoxy. But the still, small voice inside said that I should do it the Right Way. So I measured the length of plywood that I would need and lucky for me I could still make one more scarfing attempt! I cut out the bad scarf and am in the process of re-sanding the angle so I can try again. I am not sure what I screwed up last time. It seams like there are two possibilities, the alignment and the squeeze. The alignment means getting the two angles matched up correctly. If they were too on top of each other it would cause the lifting of the tips. But the rest of the face would match up and there wouldn't be a void, provided there was sufficient pressure. The squeeze refers to the pressure applied to the joint during glue time. I think you can compensate for some mis-alignment with enough pressure to smash it all together. The problem lies in too much squeeze, which would push all the glue out, making all my hard work for naught. Since the lifted tip runs the whole length (almost) of the scarf, I assume that pressure was approximately even but maybe just not enough. It's worth mentioning that my sanded angles were not perfect, but not that bad either. Like I mentioned in my last post, I didn't use two mixes of epoxy. I have learned that epoxy covers all mistakes, and in this case the extra might have filled in the gap I left. Since my angles are much closer to perfect this time, I will have to load up the epoxy, crank down the clamps and triple check the alignment. A dry fit might be in order too.

All good times must come to an end

I never thought I would be waiting on the weather so I could work on my boat. The Charleston summer was long, hot and humid as always. Plenty of building time that I squandered doing who knows what. But since it has gotten much colder and I am pretty sure epoxy doesn't like the cold, I wait for better weather. I suppose at some point I will just get a space heater so I can make the garage warm when I need to glue something. Today while I waited I moved on to the sheer notches. The first thing I learned is that I should have at least cut the base notches while the frames were upright. Upside down, while laying on the cold concrete, when you can't move to see both sides of the wood to check your line is not an easy cut. I did manage to get all the notches cut in one afternoon. And they were close to what they needed to be.

Since my chines needed no steam to make their bends I figured that the sheers wouldn't need it either. NOT a good guess. I just wanted to see how it would look (I am sure I am not the only one who has done this,) and, SNAP! The sheer snapped right at frame 5. It didn't break completely through, it just split the outside where the wood was being stretched. No creaking, no cracking, just SNAP.I don't know how I can fix this one. This piece is perfect for the sheer (well, before I broke it,) So I would love to salvage it. I could scarf on another piece since the break is toward the end. I thought about packing the break with epoxy (lots of surface area in there) and flipping the sheer around. The break would be on the compressive side and I would be sure to steam the sheer before I tried to bend it again. I will actually steam the sheer anyway before I try to bend anything again. I guess I got lucky with the chines, but I am not going to rely on that anymore. To add insult to a bad work day I found one of my chine glue joints with a crack in it.

I don't know why it cracked, it just did. Maybe it was too cold to dry right. Maybe it was mixed wrong (nah.) Whatever the case, since the crack is only on one side of the joint, I don't think I need to worry too much. I will probably just sand it down and re-filet the joint to make it look nice. So, all in all, a productive weekend. I love when work makes you've done makes you think about how to fix it.

Gluing Chines

I decide that if I ever want to get this boat done I had better start really working on it. No nights off for Monday Night Football! This was reaffirmed when I was mixing epoxy tonight and something just didn't feel right. It was 65F in Charleston, SC, a sure sign that fall is coming quick. Epoxy has a different consistency when it is too cold; it really liked our 80F+ summer days. I was mixing epoxy for the chines. After many hours fitting, clamping, marking, un-clamping, chiseling, rasping, fitting and clamping again (and again) I decided that enough was enough. I drilled the pilot holes (not without incident) and set to mixing the epoxy. I made up some shims so the chines sat in their notches perfectly. These got coated first and set in place. Then each of the notches and the chines got a dousing with epoxy. I wanted to make sure there was plenty to go around. Then I sunk the 2" bronze screws and removed the clamps. I fit and cut the chines from the front so the length and angles would be correct. Now that I am actually gluing them up I am starting at the back.

Looks better without the clamps. I glued the chines from the transom all the way to the front of the centerboard trunk. Since the front parts of these get really tweaked on, I will wait a few days before I do that part. In the mean time I still have my wide bottom plywood panels to get scarfed and the sheer (upright to deck joint) notches cut out. Knowing what I do know about fitting the chines, the sheers should be easier...

So you are probably wondering what this is. The picture actually doesn't do the MASSIVE hole in the chine justice. In fitting the chines I actually dry fit and screwed them in so I could make shims. Turns out that 2" #10 screws don't want to come out so easy. This one (of 4) was finally stripped so bad that there was no saving it. I drilled out the head, but still it held. I tried to drill out the shaft and broke two drill bits, and still it held. I switched to drilling out the wood around the shaft, broke another drill bit, and still it held. I used a screw driver as a chisel, mangled and enlarged the hole until I was sure that I was endangering the integrity of chine, but still it held! Finally, after about 30 minutes of work I loosened the screws dead grip on the wood enough to pry the chine away from the frame. Then I still had to get the screw out of the frame! I really need some vice grips. Since I am now confident that this particular piece of mahogany is pretty much indestructible, I drilled a new hole right next to the gaping wound and filled the gouge in with epoxy. Due to the close proximity, I also filled in the screw head. I actually thought to myself that that simple action may not have been wise, "just in case" I needed to unscrew this particular screw. I should have known that my much under developed boat building senses were picking up a problem. I didn't fill any other screw heads. As I was wiping up the excess epoxy and making each joint look good, I felt a small protrusion behind the mangled chine/ frame joint. The shim that was supposed to be underneath the chine had somehow slipped behind it. So now not only was the space underneath the chine all epoxy, but the shim was trashing my hard work to make the back side of the chine fit the frame snugly! Double whammy! Lucky for me I was way ahead of that slippery shim. I had packed that joint (all of them actually...) so full of epoxy that I am sure it won't make much difference. And while the excessive use of epoxy may have contributed to the shifty shim's quick escape, I think I still won this round.

Scarfing

I began the sanding process for my scarfed panels about two weeks ago. I have one set for the sides that is 19" wide and one set for the bottom which is 29" wide. The 19" ones were shaped first so I decided to put my scarf jig to the test. The jig can be seen it a previous post, but it consists of a 4' x 4' piece of 3/4" plywood, a 6' piece of STRAIGHT el cheapo pine and a 2 x 4. To get even pressure on the joint I planed down the ends of the 2 x 4 to enhance the boards natural camber. I used two bolts to hold it all together while the epoxy dried. Since the exposed part of the plywood is essentially all end-grain (likes to soak up epoxy) I mixed two successive batches. The plywood didn't soak up as much as I thought it should, so next time I'll just mix up one slightly larger batch. Epoxy will chemically bold to itself if it is not cured yet, so pre-coating with one batch, then using another to actually stick the pieces together produces a very strong bond. You get about 45 minutes from what I have read. Since My plywood didn't look like it was going to soak up any more epoxy I only waited about 10 minutes between batches. After clamping it all together I had to stay out of the garage for a day so I wouldn't be tempted to release it early.
The finished panel is 15'9" since the two 8' panels overlap 3". That is a pretty long panel to move. Since the epoxy won't be at it's ultimate strength for about 5 days (maybe longer, it's getting cooler here) I was worried about moving them. Even with the widest grip I could manage I still had visions of plywood snapping. The scarf joints actually look pretty good. There are some spots where glue didn't squeeze out, but when I tested them with my finger they are hard about 1/4" under the edge. I will fill these with epoxy before I put the panel on the boat (and put that side toward the inside.)

More chine work...

I worked on fitting the chines better this weekend. To add on to my last post, I needed a way to fix my wavy chine. After some thought, advice from those who have gone before me and looking at how the other side fits, I decided that the best way to fix the problem was to add some material to the frame. That way the bottom of the hull will be supported and everything will have a nice "boatly" shape. Boat building, like life, is all about the recovery. I think that the problem actually stems from not getting the angles exact enough when I made the frames. Since that was a long time ago, I'm going to let that one go.

The chines match well across the hull. There is about a 1/8" difference left and right. Both chines make a nice curve and hit the frames at all the right spots. I am working out where the chines will intersect with the stem.They are very well matched at the stem so I won;t have to adjust them too much.

I am also setting up to cut the chines for gluing to the stem. The angle is tricky and compound so the best way to cut it is to pull the chine tight to the stem and use the stem as a guide. I just have to find a way to keep the chines tight while I start the cut. This picture was taken with a little bit of elbow grease and a lot of twist put on the chine. The trick is to hold it there while I cut it. Anyone have a hand to lend?
Once again my boat work timeline is more optimistic than life really allows for.

Chine fitting

I started fitting the stbd chine I quickly found my first chine problem. Either the angle that I glued frame 1 at is wrong or something else doesn't line up right. I cut the notch in frame 1 first. Of course when I made the frames with plywood gussets six months ago I was not as careful as I could have been. I had to cut right through a nail. This was not starting well. Since the nails are made with rings shanks, ribs around the nail shaft, they don't want to come out easily. A hammer, screwdriver, sliced thumb, chisel and two sets of pliers later the nail was finally out. The chine looked great fitted between the transom and frame 1. But when I cut the notch in frame 2, (working forward,) the chine didn't fit into frame 2 so well. I continued cutting the rest of the notches thinking that once I bent the chine into place it might be tweaked into the notch better.

That was not the case. The chine rides high in the frame 2 and 3 notches. If I clamp it down tight to frame 3's notch then it fits from frame 3 forward just fine. But it still rides just less than 1/2" high at frame 2. If I clamp the chine into the frame 2 notch then it has a nice wave shape, not the "flowing curves" that the plans call for. So I have to think this recover through. Frame 1's notch is holding the chine too high as it comes off the transom. If I cut the notch deeper into frame 1 then I will have to take off a lot (1/2" maybe?) of frame 1 material to make the top of the chine match the frame. I could let the chine ride high since there is plenty of chine material and fill in the 1/2" gap at frame 2. Either way I want the curve to be nice and smooth and I think both will accomplish that. I wish I knew which was the offending piece. I (briefly) thought about remaking frame 1. Since it is already EPOXIED to the keel, that thought passed quickly. Not impossible, but thats the first word that comes to mind.

I still have some cleanup work to do on the notches. On my frame 1 notch I was super careful to mark the angle of the chine as it was clamped around the outside of the frame before I cut the notch. The notch was off anyway so I decided that the others would start with a rough cut and then I would fine tune the notch once the chine was closer to it's final resting place. A few more hours of work and it might be ready for some epoxy. Maybe even this weekend...