How do I keep my strips from getting glued to the stem mold?

Ben · Post by **Ben** » Wed Sep 02, 2009 8:10 pm

Here goes - this is my first question of many to come. I am building a Freedom 17-9, and I started shaping the stems. My stem molds are made from 3/4" plywood, so I am having to plane off some of the mold material to get the angle right on the stems. I would rather not shape the entire stem until I start to strip. Since I can't really tape the mold before I shape it, how can I seal it so any glue squeezeout doesn't stick to the mold? Can I coat the endgrain of the mold with paste wax, and then wax the sides of the mold as I am gluing the strips on?

Thanks!

vann evans · Post by **vann evans** » Wed Sep 02, 2009 10:18 pm

I built a Freedom 15, so I assume that the bow and stern shapes at the stems are similar. I also used 3/4" plywood for the forms. I made my inner stem 3/4" wide and did not need to shape the mold(Both the mold and stem are equally 3/4" wide). the inner stem itself is the part that gets shaped as you add strips. It starts out at the inside(form) edge being a full 3/4" wide and becomes tapered at the outer edge that will eventually join the outer stem.

I used clear packing tape on all of the form edges and did not have any problems with the glue sticking to the forms.

Vann Evans

vann evans · Post by **vann evans** » Wed Sep 02, 2009 10:23 pm

I just checked out the book to get more info-look on page 117 and you will see the profiles of the inner stems at different areas of the stem as you progress from sheer to keel. It clearly shows that the back edge of the inner stems stay a full 3/4" in width throughout the stem.

I did not shape the entire stem at first, but shaped it as I laid up the strips, shaping it 3 or 4 strips ahead of the glueing by using the batten method that is mentioned.

Hope this helps.
Vann Evans

Post by **Patricks Dad** » Thu Sep 03, 2009 9:00 am

Depending on the hull design, the inner stem may not remain a full 3/4" thick. Particularly the bow stem for (asymetric) designs the approach from the last form to the stem may be quite acute. The Redbird is a good example. I used 5/8" plywood for my stem molds so I didn't have this problem but I understand what you're talking about. I build the Freedom-15 as well with 5/8" molds and didn't have this problem. But I don't recall the inner stem on the Freedom-15 getting smaller than 3/4". I used the Michne stick approach to shaping my inner stems as I went along and did scuff up the packaging tape I used to protect them so had this same worry....

What I did was simply shape my stems as I went along and as I scuffed up the stem mold I put pieces of tape back onto the stem mold before I added new strips. With 3/4" molds, you might consider rasping the leading edges somewhat to make them a bit narrower up front, tape them and then patch the tape as you go if needed. I'm not a fan of wax. I worry about introducing wax to my strips and having troubles with getting it off prior to glassing (and up in the ends it will be difficult to really clean well - or see later).

just my .02.

Snowman · Post by **Snowman** » Thu Sep 03, 2009 6:17 pm

I use wax and it works fine.

The question of having this problem is a function of your mold material thickness and hull design, influenced by the entry angle and how fine of stem you go for.

Snowman

Ben · Post by **Ben** » Thu Sep 03, 2009 10:54 pm

Thanks for all of the advice. I am going to remove the stems and shave down the mold to the bilge, then tape it. I am probably only shaving 1/16 off of each side. If I don't go far enough up the mold, I will have to wax it. My only other issue right now is that I bought too much wood, and I am having a hard time deciding when to quit ripping strips. I bought 85 bf in lenghts ranging from 8 1/2 to 12 feet. I have 190 strips cut with about 21 bf left, but I just can't stop cutting. I may have to cut the rest for an excuse to build the next one. :twisted evil