Saturday, June 26, 2021

Inner Stem

Tonight (Saturday) I glued up the inner stem. I had a bunch of strips left over from trimming the Douglas Fir that I had used for my 2 masts. It turns out I had just enough to do the inner stem. Actually, one broke as I dry fitted it, so I had to cut another from a larger piece of left over DF. Hopefully the stem will turn out alright. It was a messy job and I mixed too much epoxy. I'm usually pretty good at estimating, but over-shot this one. 

I used the strongback with the OSB on it as the backdrop for the glueup. I laid all of the strips out side by side on another section of the strongback. Then I coated both sides of each strip with straight epoxy, coated one of each pair with thickened epoxy, put the pairs together, coated 1/2 of the pairs and put them all together in one bunch. I forgot that I wasn't supposed to coat the outside pieces. My clamps will be a bit messy though it was only straight epoxy, not the thickened stuff. 

Once they were in a bunch, I placed them near my form and slowly pulled the middle in with two strong clamps (the orange ones with the screw down ends), alternating back and forth as each one was screwed down as far as it would go. Near the end, the inside strip broke. It was pulled in so far and looked decent, so I put another clamp on the break and left it. I think it will be ok.

Here is a pic of the stem's line drawn with a batten. The second pic shows the nails offset the mark enough to allow for the thickness of the batten. The third pic shows the strips clamped down to the blocks which were set back 1 and 3/4" (which is to be the thickness of the stem) from the line. 



Here are the blocks set up for clamping.


And then the strips glued and clamped.

Update Monday night:

I removed the clamps and sanded off the squeezed out epoxy. I realized that the stem was a little short of the 1 and 3/4" that the plans called for. I actually had left out one strip because I thought it was going to be too thick, so I went back and added that last strip. Even with it, I believe I'll be maybe a 16th too thin. I'm not worrying about 16ths on this build. 

Here is the stem after taking the clamps off. You can see the squeeze out.



Here is the stem with that last strip added.


One thing I noticed: I believe the stem sprung back from the clamped shape just a little. I don't think it will make a big difference, maybe 1/2" less curve at the roundest part of the stem. The top and bottom will be on the mark. 

Here are three pics; one at each end and one in the middle of the stem showing the "fit". The first one show the top with maybe a 16th shallow.

The second shows the middle with about a 1/2" gap. 

The third shows the garboard end with a close fit. 




I think I'm going to go ahead with this as is. Clint seems to think it will not make a big difference.

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