LM 18 with Tunnel Build - Texas

[fallguy1000]

Fill em with thickened resin. Final gap is best at 1 millimeter.

[Fuzz]

I would think the stringers are ok. Maybe needed a little more glue or more clamp pressure or both. The gap at the butt joint is short on glue and needs to be filled in. While things may not be perfect this method of building is so strong I am guessing you are good.

[GrantL]

thanks both for your feedback! I was using Gel Magic for the glue so will mix up a little bit more and fill in all the gaps on the stringers.

Next up the frames.... For that, i was going to set the transom and Frame A and and then work towards the middle, is that a good plan?

[Fuzz]

I am pretty sure the plans will tell you the best way to move forward.

[GrantL]

Glued up second and third pieces of transom and filled in gaps in stringers as discussed with gel magic. Will start assembling the frames on jig tomorrow as well as glueing together puzzle joints on panels.


Question - can I use the gel magic for the puzzle joints or stick to a thickened epoxy with wood flour? Or some other compound y’all recommend?

[joe2700]

Glued up second and third pieces of transom and filled in gaps in stringers as discussed with gel magic. Will start assembling the frames on jig tomorrow as well as glueing together puzzle joints on panels.


Question - can I use the gel magic for the puzzle joints or stick to a thickened epoxy with wood flour? Or some other compound y’all recommend?

You can use gel magic pretty much anywhere you need thickened epoxy as an adhesive, so don't see any reason not to use it for the puzzle joints. I see lots of people here recommending ways to avoid using gel magic since it's more expensive than mixing your own, but if you aren't trying to minimize your use of it then it's a great tool for the job.

[fallguy1000]

All those clamps are really not needed.

Just glue those up on the floor with a locating pin so they don't slide much.

The way you are gluing in the air like that is going to result in bends or broken feets.

Lose the clamps next time. Put all the weight on timbers on 1/3rds of the piece and make sure the pieces have a pin through them in 3-4 places.

Looks like about 400 pounds on it and that is good.

Otherwise, carry on.

[GrantL]

Hey folks, been wrapped up with work and finally caught a break to knock out a few more items.

Spent some time finishing the transom and stringers. assembled the molds tonight on the jig and placed the stringers in the notches. I spent quite a bit of time leveling out the mold frames and ensuring they were straight and true running down the jig. I did this by measuring per the instructions (between each mold) and then running a string inside the notches from from to back to ensure the molds were straight (left to right). After ensuring everything was true, i placed stringers in notches and called it. A few questions below...

Only major issue i had was that the stringers in most molds were not flush and usually 1/8-1/2 inch above the edge of mold. I tried using a soft mallet to force the stringers down further but no luck. Any suggestions? should i just cut notches deeper until the stringers lay flush with mold nothches? see pics below for example.

Any advice on how to brace the transom to the stringers when mounting? just a lot of clamps?

Just fyi, the particle board for frames C and D are too thick for the pre-cut notches in stringers. I had to use a dremel to widen out those notches to get them to fit down into mold notch

[fallguy1000]

If the stringers are too wide; they won't fit. If the notches are too shallow they won't fit. If a station mould is too high they won't fit. If the stations are not leveled to the waterline they may not fit.

Lotsa variables.

Most likely a laminated stringer is dimensionally incorrect in some way. Ideally, you determine a way to make the stringers right because if they are uneven; that variation of 1/8 -- 1/2 can translate to the sole if you jist notch deeper.

[VT_Jeff]

One approach is to cut those notches a little bit over depth and then shim them back to level. You won't rely on those notches being the exact right depth when you assembly the boat, you'll be spacing the stringers and frames off the bottom and spacing the stringers and frames from each other to ensure you have gaps everywhere. This ain't shaker furniture.

I supported my transom with a "dead man" to take the weight of the stringers, just a 2X4 clamped on that ran to the floor. I screwed some 2X2 to the back edge of the stringers and then screwed the transom to the 2X2. This worked well for me and required no clamps.

The transom is actually going to be attached to the sides and bottom at this stage so it's position and fit is a little more important than the stringers and frames which are only acting as molds at this point. As long as your panels are fair when they are stitched, the molds are doing their job.

One thing I messed up was over-tightening my side-to-bottom stitches, causing the side panels to flare at the sheer, resulting in a lot of extra effort to get them into proper shape after I flipped. Beware large gaps between your molds and side panels at the sheer and correct before glassing.

That's my .02, worth every penny!