TMS-20 Update

Thought I’d start a new thread fitting the bulkheads and the bow work is kind of interesting for those that want to follow along. The tube is done - the Kevlar was an afterthought it would have been easier to wrap the tube and reinforced the bulkhead before mounting both in the hull, I’ll have to make a note of that.

The first bulkhead will have the forward chain plate mounted to it. Pictured below the bulkhead is tacked in place with bog, leveled, and duct taped to dry overnight. Once dry the starboard hull half needs to be fitted and the bulkhead shaped if needed. The forward chain plate location will be determined and the mounting holes marked for the chain plate. The mounting holes will be over drilled by 1” and the Delron rod cut and glued in each hole. Then the bulkhead will be glassed in place on the port hull half with Kevlar for strength, (already has 600 grams of carbon on each face in the chain plate area) and to keep the Delron plugs in place. The Delron plugs are to prevent the machine screws from pulling through the foam core material and the Kevlar for shear strength transferred from the chain plate.

More ..... Cut for the sprit pole and tacked in place.

from an efficiency standpoint, is it better to lay up (or vacuum bag) large sheets of bulkhead and then cut to fit, or mold each piece individually?

Structurally, would this method be as strong (since you're sawing up the stuff after curing) as molding each piece individually?

It just seems that if you designed a large piece scribed with all the smaller sections on it (like a puzzle), you'd only have to do all the bagging once, and then get a tiny band saw to cut the rough shapes for all the bulkheads.

Shouldn't be any structural disadvantage to doing it in one solid sheet and then cutting. However, the way the Man Shed is doing it is easier to get a good fit. The foam is very easy to sand/whittle into a great fit. After you cover it with cloth, then you just cut away the cloth from the edges of the fitted foam and you're good to go.

In a production set-up from a fiberglass female mold you could pop them out from a sheet that has been laid-up. In one-off you have a tolerances difference from side to side - I find it easier to fit and trim the foam first.

Also it is easier and less itchy to trim soft carbon that has not fully cured with a razor knife on each piece then to saw up a hardened glass sheet and sand to fit. (Unless somebody else is sanding!)

Starting to look like a boat, laid it there to get inspired and fit chain plate location..

More detail work on the front bulkhead. Extending the first bullhead for the top screw, had to cut away part of the flange area and re-glass, and cut an opening for the chain plate. Drilled pilot holes for the hole saw then bored holes for the Delron plugs and glued the plugs in place.

I flipped the pictures to show the boat on the correct axis hope it does not throw your vertigo off.

More...

last batch tonight...

Busy weekend - even passed up a day of sailing but I had some help around to lift the hull on and off so I took advantage of the help.

Pics:

1) I put some clay on the bulkhead and place the hull half in place to check the clearance.
2) Sanded out the bulkhead and marked the area for a cutout to get to inside of the hull to finish up the work once the hulls are joined.
3) Kevlar lay-up to shore up the bulkhead and several layers on the face of the bulkhead. Chain plate clamped in place to make sure everything fits.

Pics...

1) Put some bog over the Kevlar so I can sand it fare. If you have ever sanded Kevlar you know why. Also to the left you can see the cutout for access to the inside of the hull.
2) Here I can see the bolts to the chain plate so if I see them I can get to them, I'll do the finish work with the chain plate off. You can see the bog that spilled out when my tape let go no big deal some will stay in the faring some will be sanded away. Cheap tape = extra work.
3. Front of the bulkhead attached to the hull and the beginning of the flange for the cutout. I'll let it set then Kevlar the rest of the bow from the bulkhead forward and finish making the rest of the flange for the cutout.

Almost done with the bow work. The rest of the bulkheads will not be as bad and should go faster.

Mike