catzooks.com


Building bevel blocks


posted 2004 Feb 29

Did more catching up on the little bits this weekend, and more work on the bevel blocks.

I glassed the backing blocks on the transom. To get the right shape, I used a blank I had cut that turned out to be too small, but was still cut to all the right angles. I laid it down on the glass and traced it's outline, and then cut. There were a bunch of strands of glass floating around, but it worked out ok. Once I had applied it and the epoxy had cured, I used a file to take off the rough spots, which worked out pretty well.

I sealed the holes in station 6 with some leftover epoxy. This time, instead of putting a line of epoxy over the edge while the station was vertical, I laid the station flat and painted the inside edges. It made a lot less mess on the sides, and while I doubt it's as good a seal (the spots with end-grain in particular could probably use more), it's certainly cleaner.

I cut the transom bar to roughly the correct length. I centred the bar on the transom, then scribed where the cut should be - then added 1 1/2 inches outwards and cut there.

I shaped a new vang pedestal. Bram says here that the top diameter is 2" and the bottom 3", and the pedestal I first build had a flare maybe slightly less than 3" on the bottom. It doesn't really have the "flare" I want on the bottom edge though, so I built another one. I bonded together 6 layers of scrap bulkhead material (I've got plenty of that ;-) with epoxy/406, then sanded off the excess epoxy on the edges until the cedar was showing through. I put the cylindrical block on my drill, and used the power sander and the drill to turn the right shape. This time, I never used the flat part of the sander - only the curve at the end of the belt. I got a much nicer pedestal, and it's also a lot more circular than the first attempt (although I think this is luck, not much more). Be sure to tighten the chuck a bunch of times, otherwise you're sure to wind up with an oblong pedestal.

For the bevel blocks, I did the following.

  • I cut all the remaining blocks out of the bevel, each 4" by 2 1/2". I botched one because I cut to aggressively at the end of the cut, and ripped out the wood. That one was put to use as my test-bed for testing hole sizes.
  • I bevelled in the sides on all the blocks, 7° on the sides and tall edge, and 12° on the short edge. 12° seemed to look a bit better than 7°, 7 just wasn't enough. I also shortened the blocks down from 4" a bit so that a clam cleat fit with maybe 1mm extra on the top and bottom.
  • I sanded the vertical corners to round them down a bit. A block is best for this, the ROS is too big and unwieldy for it.
  • I marked the spot where the holes should be drilled, by putting the clam cleat on each block and marking the centre of the mounting holes. Two cleats per block. Each hole should be 3/8" in from the edge, this is the radius of the tee-nuts.
  • Pound a starting mark with a nail, then drill all the holes with a 5/16" bit. This is slightly wider than necessary, but it makes the bolt threads go through cleanly. When they're drilled, clean up the glass side hole with a triangle or circle file. The only trick here is to make sure that for the bottom holes, you drill at vertical, but with a very slight angle back, so the hole is maybe 5° off vertical towards the narrow edge. I did this by drilling as soon as the "level" light on the drill went on. This makes sure there is enough room for tee-nut on the bottom edge.
  • Grease the threads on all the stainless steel tee-nuts, and then drill out a slightly larger (3/8") hole for the shaft of the tee-nut.
  • Cover the bottom holes with tape, putting the tape on the side if the drill ripped out any wood on the bottom edge.
  • Mix up some straight epoxy, then fill up the holes with a syringe. Keep the holes full, as the wood absorbs the epoxy. Watch the remaining epoxy in the mixing container - when it starts to get thick or appears to kick, pull the tape off the bottom and let all the epoxy drain out. Wipe the bottoms, and make sure there is no epoxy "skin" covering up a hole.
  • Pound the tee-nuts into the bottom, and then run a Q-tip through them from bottom to top to clean out all the wood chips that might be in the path of a bolt in the hole.
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Epoxy Rash


posted 2004 Feb 28

I managed to get a small dollop of uncured epoxy on my forearm by my wrist, and because I was right in the thick of epoxying stuff I didn't clean it off immediately. Big Mistake. I can safely say that when the MSDS sheets say "May cause moderate irritation to the skin such as redness and itching" they weren't kidding. I've had a small poison-ivy like rash at the spot for a week now, and it itches. If I knew then what I know now, I would have stopped immediately and cleaned the epoxy off.

•  •  •

When I cut the cloth for the transom, I cut the 50" wide s-glass into three strips (like the Netherlands flag) - one each for either side of the transom, and a strip left over which I just hung onto, figuring it would be useful at some point.

And how - all these little pieces need more little pieces of glass to go over them, and that strip has proved very useful.

On Corrosion


posted 2004 Feb 26

I went down to the local Home Depot to pick up tee-nuts to embed in the bottom of the centre rail/vang pedestal, as well as the bevel blocks I just built, and while talking to the guy about thread counts (he suggested 10/24, which Bram later confirmed), he suggested using stainless steel for the bolts. Reduces rust. I knew that different metals would cause problems with corrosion, and all they had were zinc tee-nuts, so I started to wonder how to fix this problem. Could I drill a slightly larger hole and embed a SS nut & washer?

So, I joined a Sailnet mailing list for Puget Sound sailers, and asked there. I got a few good responses:

Ken Fischer (ksfischer@mac.com) suggested

Were it me, I might well go with your idea of using SS nuts and washers.

Try cutting a hole in a piece of wood of similar thickness to the nut and washer. The diameter of the hole should be a bit larger than the washer.

Put a piece of tape across the back side of the wood. Superglue the nut and washer together and then stick them down to the tape, inside the hole. Use a dab of tape to cover the top of the nut, as well.

Mix some epoxy and use a brush to just wet the wood inside the hole, and the surfaces of the nut/washer, which you would have cleaned with acetone. Then add cotton flox to the epoxy until it is a thick, but wet paste. Use that to fill in the area, essentially making an epoxy casting.

When cured, peel the tape and you should have a pretty good nut that can be glued to the back side of just about anything, with no worries of the nut falling or breaking off.

Duncan Forbes (duncan.forbes@ints.com) suggested

Now onto your problem, I don't think zinc plated nuts would be a terribly good choice. I would think stainless would be the way to go. Where have you looked for T-Nuts? I popped out onto the internet and did a quick search and found a couple of on-line sources for stainless T-nuts. However not knowing the size you need I couldn't find an exact match. I used a google search for the keywords "stainless steel t-nut".

Here is one promising link though: stainless tee-nuts.

Another writer suggested that anything I could describe I could find at mcmaster.com, which after a bit of searching does indeed seem to be the case...

I also took a book out of the library: "Metal corrosion in boats: the prevention of metal corrosion in hulls, engines, rigging, and fitting", by Nigel Warren (Dobbs Ferry, NY: Sheridan House, 1998). This was way overkill for my purposes, but it did have some nice pictures of how nasty corrosion is, and you don't need two different kinds of metals...

Here is more information I collected.

Catching up


posted 2004 Feb 25

This week has mostly been devoted to completing all the little things that I haven't done in previous steps. i.e.:

  • I cut the vang pedestal in half with my trusty razor saw (have I mentioned how much I like this saw?), and bevelled the straight side to 10° inwards to match up with the centre rail.
  • I cut the breather holes (but not the drain holes) in station 6. I used the old station 6 to place the locations of the small 2 1/4" holes, and then measured out the positions for the 3 1/2" holes - being very careful to ensure they were at least 4" apart. The drain holes I'll drill later when I can ensure that they match up well with the centreboard trunk.
  • I laid down the carbon tape on side two of station 6 (side one I did while I was applying hybrid to the board). Scraped it up with 40-grit on the sander, then used a brush to apply the epoxy to two pieces of overlapping 1 1/2" carbon tape. Applied a second coat of epoxy when the first was tack-free. [Update 2004 Mar 15: It may have been a good idea to put peel-ply and plastic down on top of this (and then perhaps a layer of thin foam, so the epoxy doesn't just migrate to beside the tape), then a board, and clamp it down. This would have reduced the total epoxy used, and would have made things a lot smoother and flatter. Next time, I guess.] [Update 2004 Mar 22: I think also it might be a good idea to vacuum bag both the bulkheads, just to reduce the total amount of epoxy in the hybrid. Greg talks about this here.]
  • Put a 25° bevel on the bottom ends of the T-soldiers, using the disc sander and the angle guide, then used extra epoxy from the carbon tape to seal the exposed edge of the bevel.
  • Cut a piece of scrap bulkhead hybrid, 6" wide, to use as the backing block for the gudgeon which goes on the transom. I traced around my hardboard pattern to get the right shape.
  • Cut and bonded the backing block for the transom bar to the backside of the transom. Take a piece of solid cedar, 12" long by 2" wide by 1" thick, bevel the back edge to 45° picture. Cut in half, and bevel the inner edge to match the transom 'step' edge (about 20°). Once that's done, bond the piece to the back of the transom. I inset mine about 1/8" so there's a bit of extra to sand down when the deck is installed, and it makes it a bit less messy because the epoxy can collect in the 1/8" lip. I used epoxy/206/406 and a bit of s-glass for the bond - in retrospect the 2" e-glass tape would have worked better because the edge is finished on the tape, and strands of glass wouldn't be pulling out and it's exactly the right width. The block wants to slide all over when you apply pressure, and the glass wants to slide out, so be careful.
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Building the centre rail


posted 2004 Feb 22

I've been doing the construction of these parts a bit out of order - since I built the strips for the centre rail, I figured I would lay those up and do the work for them, while I was completing other parts. At this point the book starts building the centreboard trunk and mast step.

So, I layed up the centre rail - epoxy/206/406 together and 2" e-glass tape every other layer, three strips wide and 6 strips high. (I had previously built the 3 wide strips.) I used nails hammered into my trusty workbench to ensure that the pieces didn't slip out sideways - this worked pretty well, cheap, easy, and didn't involve clamping, which would have been hard. Even with my experience with the transom bar, I still had a couple voids, and I had even taken a couple strips off and re-applied extra filler to ensure that everything was nice and full. I guess excess is the order of the day. I weighed down the layup with paint tins and glue - just make sure they are applying even pressure side-to-side.

While the rail was curing, I worked on the bevel blocks. For these, you take a 5/4" by 6" piece of solid cedar, and cut it 16" long by 5" wide. Then split it on a bevel of 12°. This completely confused me (although in retrospect I'm not sure why...) - the split should look like this:

Split the bevel block like this
12° is (basically) the exact angle that cuts the piece in half along a diagonal between opposite corners, when looking at the piece end-on.

Well, I had a piece of 2x6 solid cedar, and I choose to interpret 5/4 as 1" (Bram indicates this is about right here although it depends a lot on who you ask - 5/4 is a rough lumber dimension, and when it gets surfaced it changes). I tried taking a bit of the height off with my jack plane, but it would have taken forever. And then how to cut something on a 12° angle?

The woodworking alias came to the rescue - someone assisted in planing it down, and ran it through his table saw for me. I think this is the only spot where I've really needed one.

That accomplished, I took one of the bevelled pieces and, along the bevelled side, stacked the following:

  • a thin layer of epoxy/206/403 on, to seal the wood
  • a layer of e-glass
  • another layer of epoxy/206/403. Note that I'm using 403 here instead of 406 - it seems like a better choice for this usage (laminating instead of bonding).
  • a layer of strips, cut to 5" long, with the 206/403 mixture between strips. 5" was just barely enough to cover the length of the bevelled edge.
  • another sealer coat of epoxy/403, this time with 207 hardener (since we're on an outside surface now).

Apply pressure and let cure overnight. All in all, pretty quick. Once that had cured, I did the following:

  • sand down the surface (pretty quick with a fresh 40-grit pad an a random orbital sander)
  • seal the bare wood surface with epoxy/207/403
  • apply another layer of s-glass, and let everything soak in
  • finish off with epoxy/207.

With the centre rail cured, I cleaned it up and took off all the extra epoxy on the sides and top/bottom. I then used the disc sander with the table adjusted to 10° to bevel both sides to the right angle. My kingdom for a table saw - this would have taken two minutes, and been more accurate, with one. But the sander worked out pretty well, as long as you're careful. I also bevelled the last six inches of the end of the centre rail - so it tapers down from the top to 1/8" from the bottom.

Oh, and I also bonded the rudder gudgeon to the transom bar, cleaned up a little extra s-glass which was sticking out (using duct tape to protect the bar), and added a fillet of epoxy/207/406 to the edge.

[Update 2007 Feb 3: There was a question on the list about the dimentions of the centre rail; Bram's rail is 1 3/4” at the bottom and 1 1/4” at the top. Mine is a bit wider — 2 1/4” at the bottom, 1 1/2” at the top.]

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Building the transom bar


posted 2004 Feb 18

I wrapped the transom bar in graphite tape, and then 2" e-glass tape. Before doing this, however, I coated the edges in epoxy with 406, in an attempt to fill in some of the cracks there. I'm not sure this was completely successful, but it did help in one way. When I came back to put the carbon tape on, the epoxy was still fairly tacky - which meant that I could wrap the tape around, and then press it in to the tacky epoxy and have it stick, so it wouldn't fly off again. This helped a bunch.

With the carbon tape on, I first coated it in epoxy/207, and then wrapped the 2" fibreglass tape around (with the edges running in the opposite direction to the carbon tape). I then coated the entire thing in a mixture of epoxy/207/406/graphite powder. Later, I came back, sanded down the bar to take off some of the high edges where the tape overlapped, and put down another layer of epoxy/207/406/graphite. I probably should have used 403 or 405 for this application, since from Gudgeon's handy dandy chart it would have been less dense and more suitable to the goal of mostly fairing with some strength.

Bram posted weights of some of the parts. Here's his list, and my weights as well:

PartTarget Weight (g)My Weight (g)
Station 6 after holes10051233 (old station 6, tape on one side)
1430 (new station 6, tape both sides, no bottom drainage holes)
Station 8, both halves9341195
Toe rails1012 ea?
bevel block for sheaves58 ea?
Cleat bevel for clam with T-nuts72 ea?
Partial bulkheads, all 3 sets9021130
All 8 soldiers3381160 (!)
Transom bar9001160 (rough-cut)
centre rail w/ T-nuts and vang pedestal525?

I'm not really sure why I'm over so much: it seems like this is a lot, especially to chalk up to just extra epoxy on the bulkheads or something. Maybe I've got extra-heavy cedar? Maybe someone's scale is wrong?

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Turning the vang pedestal


posted 2004 Feb 12

I set to work on building the vang pedestal. To do this, you take the bonded 3 1/4" discs, clean out the centre hole with a 1/4" drill to get rid of the excess epoxy, and then put a bolt through the stack of discs. I used a couple fender washers to protect the surface of the discs; I used a bolt which was too long and added extra washers to make sure I had as much thread left over as possible when the tightening nut was on. Tighten up the nut tight, and then take the thread-end of this and put it in your drill. Really secure this in tightly - if you don't, it's going to come spinning out of your drill (experience talking here).

Turn on the belt sander, and fire up the drill, and start taking the side off. This works pretty well, but the discs have a tendency to bounce off the sanding belt, so you wind up with a not-quite-circular assembly. Press hard against the belt to reduce this. The bolt threads will start to unscrew out of the drill, if you see threads stop and put the bolt further into the drill (and tighten harder).

Initially you just want to get the entire edge smooth. This requires keeping the drill horizontal to the belt surface. Once the entire edge is smooth, you can start shaping it into the right curve. I found I had to press the top half of the cylinder into the end of the belt at 45° to get the right shape - flared out at the bottom, and a slight flair at the top.

•  •  •

Started building the transom bar yesterday. I took the 2x6 generously cut by a friend of mine on his bandsaw, and put duct tape over the curved edge. [Update 2004 Mar 10: when cutting pieces for the centreboard trunk, I broke a blade and put a new one in which was a lot longer and thicker than the thin, curve-cutting ones I was using. I realized that I could probably have cut this 2x6 with the jigsaw with this longer blade.] I cut 14 strips, 6x55" long, 4x56" long, and 4x57" long. I put epoxy/406 (cream) in the cove of a 55" strip, laid it down on the duct tape, and clamped it down, and then put another strip alongside it, squeezing some of the epoxy out. Cover that entire surface in epoxy/406, add 2" tape, more epoxy/406, and then put another two strips down. Keep on going until you have a stack 7 high.

The hardest part of this entire thing is keeping things clamped down while you add more strips on. The strips want to escape (obviously) - I suppose I could steam them or heat them, and this would reduce that springiness (although it would make the epoxy more fluid and harder to control, it would set up much quicker). Keeping C-clamps on the end is hard, because they want to slide off the ends - I think the trick here would be to cut a notch in the bottom edge of the 2x6 so that there is a spot for the clamp to hang on to that's relatively parallel to the angle of the strips at the end.

I think in retrospect I would build the bar this way:

  • Cut three 4" by 12" strips of plastic.
  • Cut the strips: 4x 55", 4x 56", 4x 57", 2x 58". Cut the 2" tape as well, 1x 55", 2x 56", 2x 57", 1x 58".
  • On your workbench, lay up the strips two wide, seven high, with 2" tape between each layer. Use epoxy/205/406 (heavy cream). You may need to use 206 to slow down the curing a bit.
  • Once everything is laid up, wrap the plastic around the layup at the 1/4, 1/2, and 3/4 points. Put spring clamps vertically at these points to stop the strips from sliding sideways.
  • Take the layup, and put one end against the jig. Clamp and/or tape that end to the jig. Then bend the entire layup over the jig, and clamp the middle. Bend the other end down, and clamp/tape the end.

It might also have been a good idea to have the template laying on it's side on the workbench, rather than having the bottom edge on the bench. This way it would be easier to clamp and the strips wouldn't be able to slide out as easily.

I'm not sure how it would bend, but it seems like it would be a lot easier than fighting with individual strips that are springing loose when you release a clamp to try and get a new strip down. The layup is slippery, so it's hard for the clamps to get a grip, it's hard to get the epoxy under the tape where the clamps are holding, tightening the C-clamps causes the strips to get twisted and slip sideways, and when you add a new strip all the previous strips pull the tape out and you have to fight to get it back in place.

I also discovered (the hard way) you need to clamp the middle, otherwise the layup won't get a good solid bond, and there will be air holes in the middle - you can't see this while you're working either because there's just a big mess of epoxy and tape.

[Update 2005 Aug 15: there was a conversation about how to build the jig for the transom bar, including a picture of Rob's jig. He cut the 2x10 into two pieces (in a long arc) and then clamped them together with the strips in the middle. This is an even better idea - no voids, no wrangling with bits of plastic, no problems with individual air pockets.]

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Cutting the transom


posted 2004 Feb 08

I cut the transom. This was just like cutting the bulkheads or the stations - line everything up, making sure the strips are exactly parallel to the waterline, put the pattern paper side down, and trace around it with a marker for the rough-cut line. Then cut it out with the jigsaw, and then route around the pattern. I've found that doing this rough-cut step makes taking off the excess with the router much easier, especially if there isn't a lot of excess to remove. I managed to avoid destroying the template for the station this time too (!).

Next up was completing the centre control block bevels. The bevel for these starts from 1/4" up from the bottom, and is 23° off horizontal (i.e. 67° off vertical). The feed table for the belt/disc only go to 45° - some other method is required.

Here's what I did. First, I put the table so it was set up for the belt, and adjusted it to 23°. Then, I clamped a straight-edge along it that I knew wouldn't flex much, and adjusted the belt so that it's base was parallel to the straight-edge (picture). Thus I know the belt is exactly 23° off horizontal.

The table is too far from the belt to be able to feed material into it, so I needed to create a platform to feed things in. I dug up a scrap piece of 2x6 (the end of the transom jig 2x6) and first used the table to sand down the end, and then took my pull saw and cut off an additional piece parallel to the sanded edge. I drilled two holes on the table, and two on the wood, and bolted the wood to table (see here).

Feed in the block, and when there's about 1mm remaining at the closest point, stop and move to another side. The belt is good for starting, but not finishing. The belt curves up on the sides, and so it's better to finish with the disc sander, as it is perfectly flat. And since the angle formed by the two edges is 45°, you can use the normal feed table.

For the disc, you have to be careful that the right side of the disc (which is moving upwards) won't rip the piece from your hands and give a weird angle. I found that if I gradually moved the block closer a small amount (1mm), then press the bottom edge onto the table (thus pushing the top edge into the disc), I could reduce the likelihood that the block would "jump" and pull off some weird angle.

I also cut out six 3 1/4" pieces from the scrap transom and bulkhead material for the vang pedestal. I roughed up the sides with the random orbital sander, then used epoxy/205/406 to bond them together (no need for extra glass). I put a 1/4" bolt through the centre hole while I was getting everything together, then removed it once I had the clamps on.

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Continuing the transom


posted 2004 Feb 05

Did a few things this week.

First, I scribed out the 72" arc required for the transom bar jig on a piece of 2x6. The board is a bit too wide for me to cut with my trusty jigsaw, a handsaw won't cut it, cutting a curve like that with a circular saw won't work. And so a friend is going to cut this out on a bandsaw, the ideal tool for the task.

I took the pieces I bonded together for the rudder gudgeons and used my (newly assembled) belt/disc sander to take off all the extra epoxy and glass. This flew by - that belt sander can really remove material. I then set the table up for the 45° angle on the ends, sanded that off, and the 12° angle on the sides - absolutely no problem. Making this part was pretty fun.

I bonded the 4-strip wide pieces of the centre control block bevels together. This is the same as the rudder gudgeons - epoxy/406, leftover s-glass between the layers, and clamp it together. Be sure to protect the top and bottom from the pressure of the clamps - I used a couple small sheets of plywood this time. Also, have clamps clamping all three axis (I didn't do one, the one with the length of the strips). The strips will slide out in the direction you don't clamp otherwise. My strips were cut at fairly tight tolerances, and I got lucky they didn't move so much that I had to rebuild the piece.

I had some extra epoxy/406, so I decided to cut and glue together the 32" strips needed for the centre rail. This time I used epoxy rather than carpenter's glue. Compared to glue, epoxy is hard - when I came back later and knocked off the excess resin, the epoxy takes quite a beating...

Next up was the backing block for the transom bar. This is built from a scrap piece of dimensional cedar. Since I bought all mine, I made a trip out to Dunn Lumber and picked up a 16 foot long piece of 2x6, with nice tight end grain - expensive, but ideal for what I need (I'm not sure how people build cedar decks, it has to cost a fortune). I used my newly acquired circular saw to cut a 45° cut with the grain in from the end, and then a 90° cut parallel one inch further in. (You can see the lines here.) I then cut off the piece, and put it on the belt sander to take it from 1 1/2" thick down to 1" thick. A planer would have been handy here, alas.

I scraped, planed and sanded the second side of the transom material. There is a slight bow away from the already glassed side of the transom - I'm not sure exactly why. Perhaps the temperature changed slightly, or the humidity, or perhaps even the glue between the strips tightened up and pulled together a bit. It's not terribly noticeable, so I'm not too worried about it. If I had hit the second side with the sealer coat sooner, it probably wouldn't have happened. (Note to self: be careful leaving the hull unstapled...)

Like the outside edge, I laid down a sealer coat of epoxy/406, with 205 hardener. Once that had reached almost tack free about 8 hours later, I sanded it down a bit to provide rough surface, and laid out the satin s-glass. I worked this in quite a bit this time - the sealer coat was still a bit tacky, and so the glass stuck to it. Getting all the air bubbles out is worth the time, however, they are easy to see when you're done (as I found out from the first side). It will probably be worth it to go over the entire exterior hull and putty all the staple holes, just to eliminate the bubbles - they are really easy to get, otherwise. Saturating the glass took about 9 squirts of epoxy, and I probably pulled 3 off to get it to "wet, not shiny".

Because it's cold, I've been heating the epoxy resin in front of the space heater before mixing it with the hardener. This makes a difference - the epoxy cures faster, and it's easier to work in (because it's less viscous). I almost didn't catch the "tack free" stage after applying the glass because it cured so much faster.

[Update 2005 Jul 28: it may have been better to use hybrid on the back side of the transom, for increased strength. Greg suggests that here.]

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Building the little bits (2)


posted 2004 Feb 01

Next up is preparing the outside surface of the transom. I scraped off as much glue as I could (without seriously damaging the strips), then planed it flat with my jack plane. Next up was using my new Makita random orbital sander - this sucker *rocks* and works much much better than the DeWalt sander did.

With the transom piece sanded flat, I mixed a sealer coat of epoxy up. Because it's an outside face, this needed 207 "Special Coating" hardener. To improve the stiffness, I also added a little 406. 207 gives the epoxy a yellow tint, which I don't like as much as the plain colour, but given that it also makes the surface much less prone to UV damage, I'll live with it. ;-)

While that was curing, I used a paintbrush to coat the second side of the small pieces with epoxy/205. I then moved on to putting 2" e-glass tape along the bottom edges of the T-soldiers. This is simple - straight epoxy, just saturate the fabric and bond it right on. This would have been a good spot to use peel-ply - this way a bunch of the excess resin could be forced out, while ensuring that the slight overhang of the tape over the edges of the strips could be wrapped around the strips, keeping the tape tight to the strips.

Peel ply is a fabric-type release material used in vacuum bagging. It is usually teflon coated fibreglass for high temperature molding, or nylon for room temp work. Epoxy will wick through it (similar to wetting out glass) but the epoxy won't stick to it. The wicking action will remove excess resin from the layup. When the epoxy has cured, you peel the material away from your laminate, taking the excess resin with it. You are left with a rough-textured surface which helps when you want to bond additional layers or parts to this first layup. (from here.)

Once the epoxy on the transom board was dry, I hit it with a sanding block to take off some of the high spots. The particular spots to worry about are the "ridges" that are created by drawing a squeegee along the surface - the resulting line of epoxy that runs the length of the draw. With those knocked, off, hit it with the vacuum being very careful to get all the little bits of dirt, sawdust and epoxy dust off.

Then, lay down the s-glass. The s-glass is a 2x2 satin weave, and it's very sheer - the slightest imperfections will show through the material. Small bits of dirt or dust will become bumps on the surface. Use the brush to flatten it out, and be sure to take some time to do this - it is much harder to work bubbles out of this stuff than the hybrid.

Apply resin/207 mix. I was surprised at how little was required for this surface - a lot less than the hybrid. I was prepared for 10 squirts, but only needed about 8. It's also important to work out the bubbles. Using the roller, or fingers, it's often easiest to work the bubbles to the edge of the board than to get them to "blow through" the glass, and it's a *lot* harder to get rid of them all than it was for the hybrid. Worth the effort though - those bubbles are weak, unbonded spots.

While that was curing, I bonded all the boards together for the rudder gudgeon. I used epoxy/205/406 as the glue with layers of scrap s-glass between all the boards - board, glue, glass, glue, board (repeat). Once this was all set up, I wrapped it in plastic and clamped it all together to get a good solid bond between everything. Don't forget to put a buffer block between the cedar and the clamp - you don't want to (like I did) make a nice round dent in your cedar. (Fortunately, I can put the dent on the side facing the transom...)

Once the transom had reached tack-free, I came back and used a 2" paintbrush to apply a second coat of epoxy/207. I managed to loose a bunch of bristles while doing this, and it's a hassle to fish them out, but it would be ugly if they showed through.

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