2015-04-27

Post XXIX - Inside Fiberglassing!!!

Yet another FULL day of fiberglassing. Glad to have the sanding finished for the time being!

Procedure was the exact same as the outside fiberglass for the most part. A seal coat of epoxy was applied first at 5:30 AM so that when my helper (dad) showed up we'd be ready to lay on the glass cloth. 

Figure 120: Seal coat applied to inside


.....or so we thought. Glassing the inside is way more finnicky than doing the outside glass. Getting it to cut to fit convex shape wasn't difficult but damned if we could get the stuff to stick down using rollers to apply the epoxy. The backside (lifting side) of the roller would just pull it right up off the cedar and create massive air pockets. This had us worried but we were able to force the air out by following the wet-out roller pass with a good hard squeegee pass. Once the glass was stuck and the air was forced out, it didn't lift again. After the first little section we did, we removed all the tape holding the glass up at the gunwales. This relaxed the cloth a bit in the turn of the bilge and made it much easier to stick down

Figure 121: Glass wetted out one side, other side awaiting wet-out


Figure 122: Glass now wetted out both sides


It wasn't strictly called-for in the plans, but I decided to glass the inside of the transom too. Just cut a piece to fit once the main glass sheets had cured and wetted it out. Again done with 6oz cloth rather than 10oz because it is a 1" thick piece of hardwood.

Figure 123: Glass applied at  transom


Figure 124: Shot down close in the bottom of the boat - neat curves!


Filleting was a bit of a pain in the butt, but necessary. The fillet is a structural joint that ties the glassed sides into the transom, keel and stem. Fillets go anywhere there is a corner. There will eventually be fillets around the floor pieces, around the sternpost knee, around seat supports and around seat knees. I plan to use mechanical fastenings only for the gunwales, sheer knees and breasthook since these pieces often get damaged and need to be replaced before the hull is worn out.

I used big 60mL syringes as applicators and filled them with epoxy + filleting mix. Mixture consistency is supposed to be approximately peanut butter (ie does not drip when you scoop up a gob of it on the stir stick). Any less than peanut butter and it will drip & droop while curing.

Figure 125: Fillets applied at transom and along keel


Figure 126: Same view as figure 124, but with more fillets!


Figure 127: Fillets at the bow - kinda shitty looking if I'm honest.


Figure 128: Fillets along the keel up close -- these ones turned out pretty good. 


Filleting tools are absolutely necessary for neat fillets. The simplest thing would probably be a tongue depressor like you'd see at the doctor's office; I made one out of a scrap of ash. To use, just drag it over the fillet blob making good contact with both sides of the joint and holding it at a bit of an angle so that the epoxy oozes out neatly behind. The idea is not to remove epoxy (unless there is way too much); you just need to smooth it out.

For making one, key thing is that the business end has a sharp edge and a radius that more or less works everywhere. Twisting the tool slightly will allow it to sit a bit deeper in in the fillet for areas where the radius of the tool tip isn't quite right for the angle of the joint.

Figure 129: Super high tech filleting tool I made for the task. 


Figure 130: Other side, showing the sharpened edge. 


2015-04-11

Post XXVIII - Removal from the molds, interior rough finishing

Just a quick post this time. The whitehall is now off the molds. Father-in-law was over and helped me lift it free. There were no major issues with getting it off the molds at all. I just used my wood mallet to give each station mold a good knock (to break the glue remnants free), and off it came.


Figure 116: Removed from the mold. Temporary thwarts in place.


Figure 117: From a different angle - showing the nice sweeping sheerline



With it up on sawhorses, I made a quick modification to the strongback so that it could act as a cradle instead. A couple of angled boards and braces to hold them in place. Cradles are made out of a jib halyard I retired from my sailboat a few years ago. The set-up isn't particularly mobile (as compared to dedicated cradle sawhorses) but it's much easier to have the strongback out of the way & under the boat for now. I don't plan on doing the remaining work outside either, so this will be fine.

Figure 118: View of my fancy cradle made out of old jib halyard and scrap wood


Finally, I started the task of finishing the interior. This is going to be a lot of work. The plans-seller advised me to use a paint scraper with the sharp corners filed away to do the initial sanding job. I started the process but it is looking pretty rough -- there's no way to use the scraper along the grain, and it seems to tear the grain quite badly when you use it across. 

Hopefully sanding afterward removes the nasty marks left behind by the scraper.

===================EDIT==================

Found a pic of  the nasty marks left by the scraper -- looks like absolute shit. I am editing now after having sanded all this out. It took fucking forever; it would have been much much better to just sand the inside without scraping. Grrah.

Figure 118.5: Crappy crap marks. 



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Figure 119: From the stern



2015-04-08

Post XXVII - Keel straightening, Patching & Gunwales

Tonight I straightened the curve in the keel (see a few posts back). During the fiberglassing session, Dad and I were able to take most of the swoop out of the middle of the keel using strategic application of force. Unfortunately, some of the swoop remained and with the epoxy set, it was much to late to make any corrections. Straightening at this point requires that material be cut away. I had planned for a bevel on the keel to be cut after installation regardless, which turned out to be a good idea because it gives me one last opportunity to true the thing to a straight line.

I struck a centreline down the length of the keel using a tight wire and then offset a line to either side of it. To cut the bevel, I used my larger rabbet plane and finished with my block plane using the keel-hull fillet and my offset lines as guides. The result was surprisingly accurate. In Figure 111, you can see the swoop is almost entirely gone. This is about as good a result as I could hope for, so I didn't press my luck any further.

Final prep for the keel will include a thorough sanding job, a much nicer fillet and a rounding of the keel bottom -- rounded edges are much easier to cover with fiberglass tape and much less prone to damage.

Figure 110: Sighting down the keel after it's straight


Figure 111: Another view - not perfect, but close enough.


If you recall in the last post I mentioned issues with epoxy pockets. There were several of these at the bow and they looked like absolute dogshit. Easiest way to deal with them is to just sand them away. This of course breaks holes in the fiberglass, and it was necessary to apply patches over the areas that received the most judicious sanding. 

Not wanting to build up the shell thickness overmuch, I used some scrap pieces of 6oz glass and laid them right on over top of the sanded areas. These are in areas that will receive paint eventually, so I'm not much concerned about transparency of the finished product. These areas will also be treated to a smear of fairing filler + epoxy to remove any hard edges -- kind of like using drywall compound. It's a good idea to remove a few longitudinal strings from the edge of the patches before laying them up. Not strictly necessary, but it makes an easier job of sanding.

Figure 112: 6oz Fiberglass patches over the sanded-out epoxy pockets.


Figure 113: Frayed edges on the patches.


Last job this session was to start manufacturing the gunwales. Wood can't be bought in good lengths in Atlantic Canada (at least from affordable sources) so I needed to scarph-join a couple of shorter chunks of ash. The method here was the same as every other scarph joint -- hack it out roughly with the drawknife, plane to the line on one side, plane to the line on the other side, then remove the ridge in the middle. This process is getting fairly automatic for me now and only takes a few minutes on thin stock; gunwales for this boat are 7/8"x7/8" cross section. 

The part that takes the most time now is the resawing and milling process -- much more time consuming that the joinerwork. I only had time to do the outer gunwales. Inner ones will have to wait, but I kind of want to get the inside of the hull glassed up and the knees installed before I figure out just how I want them to look anyway. Inner gunwales can wait.

Figure 114: Partially completed gunwales. Cut to the line on one side only. 


Figure 115: Clamp dem scarphs!


Not a damn thing stopping me from popping the boat off the molds now!!!