He can mold that off the boat.
CS23 Build Config: Open Deck / Closed Transom
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: CS23 Build Config: Open Deck / Closed Transom
Re: CS23 Build Config: Open Deck / Closed Transom
He doesn't need a sharp edge on his strakes, the shape he has now will work just fine, I don't know how much sharper you can get them and still cover with the fiberglass. If he wants to, he can add some cabosil or fiberglass fibers to the epoxy to strengthen it, but again they will be covered with fiberglass, and this is not a flats boat and will not be hitting anything where they are placed. Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: CS23 Build Config: Open Deck / Closed Transom
Only covered with the glass from his mould...no hull glass on these!
Re: CS23 Build Config: Open Deck / Closed Transom
Thanks for all your replies.
To clarify, I plan to make these up off the boat, epoxy glue them to the boat, then lay some glass over it (strips, not the full sheet glass that covers the hull panels - is that what you mean by "hull glass" fallguy?).
I'm also toying with the idea of making the form using glass, half filling with spheres/milled glass/epoxy, then flipping and using spheres/milled glass/epoxy to fill the rest and achieve a bond at the same time. Maybe a picture will explain that better:
Or perhaps spheres/milled glass/epoxy will not create a good bond and I'm better sticking to a cabosil/expoxy mix?
To clarify, I plan to make these up off the boat, epoxy glue them to the boat, then lay some glass over it (strips, not the full sheet glass that covers the hull panels - is that what you mean by "hull glass" fallguy?).
I'm also toying with the idea of making the form using glass, half filling with spheres/milled glass/epoxy, then flipping and using spheres/milled glass/epoxy to fill the rest and achieve a bond at the same time. Maybe a picture will explain that better:
Or perhaps spheres/milled glass/epoxy will not create a good bond and I'm better sticking to a cabosil/expoxy mix?
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: CS23 Build Config: Open Deck / Closed Transom
I don't like the proposed method because it will be hard to shape correct before applying it to the hull.
Just mould them and bond them, but the boat and part need to be scratched good, like I said.
And honestly, I see little reason to glass over them on the boat. You can and it is insirance, but to do it well is hard due to the shape.
Fairing compounds have lower shear ratings than cab and milled fiber. They sand away easy on purpose. This is easy to shape any errors, so I'd use cab.
Just mould them and bond them, but the boat and part need to be scratched good, like I said.
And honestly, I see little reason to glass over them on the boat. You can and it is insirance, but to do it well is hard due to the shape.
Fairing compounds have lower shear ratings than cab and milled fiber. They sand away easy on purpose. This is easy to shape any errors, so I'd use cab.
Re: CS23 Build Config: Open Deck / Closed Transom
I would not use glass spheres but use cabosil instead. I would also just build it in one piece and make sure your form is well lubricated, so it comes out easily. Unlike fallguy I recommend you fiberglass them on for easier fairing and better holding power at high speeds. I have been on here longer than fallguy and remember a commercial guide building 3 of these and he fiberglassed his down. Remember with a 250HP motor on this boat you will be reaching speeds in the high 40's to 50's with a lot of force on anything on the bottom. Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: CS23 Build Config: Open Deck / Closed Transom
Don't care to argue. It will be hard to glass over the shape unless you have a 3/8" radius on top and fillet the sharp inside edge.
Even under vacuum, the bag will like to bridge the inside turn which would leave voids under the glass without a fillet, but would make the top turn.
See my pencil marks for the warnings is all. The top will be almost impossible to glass over no vac.
Even under vacuum, the bag will like to bridge the inside turn which would leave voids under the glass without a fillet, but would make the top turn.
See my pencil marks for the warnings is all. The top will be almost impossible to glass over no vac.
Re: CS23 Build Config: Open Deck / Closed Transom
Again, fallguy that top edge can be rounded to 3/8 easily enough it is already 1//8. He can build the 3/8" rounding in his mold. Your rounding is 1/2" or more. Sorry to disagree. Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: CS23 Build Config: Open Deck / Closed Transom
We didn't disagree.
I drew a finger sketch and told him the 1/8" was too sharp! You are gauging my finger sketch as 1/2". Stop it!
- BarraMan
- * Bateau Builder - Expert *
- Posts: 2165
- Joined: Tue Dec 11, 2012 3:44 pm
- Location: Australia
Re: CS23 Build Config: Open Deck / Closed Transom
You can buy a 9kg bag of 75 micron woodflour from Micromilling Pty Ltd for A$45 plus freight. It cost me A$115 to land a bag in Townsville - more than enough to complete my build.Wood flour is hard to come by here so from my research I've settled on a mixture of Cabosil and Q-Cel 5020 (hollow sphere glass micro balloons).
Micromilling Pty Ltd
89 Cathcart St, Goulburn NSW 2580
sales@micromilling.com.au
I dealt with Danny Zylsra (02 48221886 danny@micromilling.com.au)
Q-Cel hollow spheres are mostly air, and therefore not suitable for anything structural. Intended for fairing only!
If you must have wide strakes rather than sharp ones like mine illustrated earlier, I would construct them directly on the hull as I did my reverse chines with a timber edge filled in with woodflour/epoxy, covered with 2 x staggered layers of 6oz biax tape.
Who is online
Users browsing this forum: Bing [Bot] and 17 guests