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Feb 08, 2020, 04:37 PM
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Topaz - F.Paine's 1935 "A" design


I have used Kevlar many times and in many different applications before. If you buy the right Kevlar, it isn't that bad to deal with. I like the durable it offers. As far as sanding, all cloth gets fuzzy when sanded. the object is not to sand the cloth. The first hull I did with the CF/K hybrid cloth, I was a little aggressive with my first sanding and had to deal with a little fuzz. after the 3rd coat, it was like glass. The 4th coat was thinned and went on beautifully. The object is not to sand it to that point. 1st coat gets a minimal sanding and, it's not until the 3rd coat of resin that you really focus on thorough sanding. On my last models, (Rainbow and Enterprise) I used Carbon/Kevlar hybrid cloth instead of plain glass cloth. I have seen how easily plain cloth punctures. These models are only getting 1 layer of cloth unlike a built up mold. With the contact that happens on occasion, (I had a built up hull punctured last year) I like the idea of hedging on the side of durability. Price online is not that bad for only 3 yds. The 5.5 oz that I'm using is quite soft. Cutting Kevlar and Hybrid cloth is not a problem if you have the proper shears.
I don't just build J's because they are easy. I select models that aren't common. That's why I chose to build Frank Paine's 1935 "A" design. It has some interesting features and there isn't another out there. I look to experiment with materials, techniques and of course design choices on future builds.
Bottom line, it's my choice. At J Days in Vermont this Spring, we'll see how well my efforts pay off.
Last edited by spinnaker225; Feb 10, 2020 at 12:13 PM.
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Feb 08, 2020, 04:45 PM
rshousha
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I'm with Spinnaker225. Modelling is a learning experience. Who cares what one uses as long as we are learning? I am looking forward to learning about this product.

Egad: "with the contact that happens on occasion". I can't imagine racing these beauties.
Last edited by rshousha; Feb 08, 2020 at 04:47 PM. Reason: more info and better grammar
Feb 08, 2020, 08:00 PM
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Topaz - F.Paine's 1935 "A" design


We just got hit with about 18" of snow. So........not a lot of progress today. Did get to turn the corner working up the rudder post. I taped the rudder template in place to get a feel what I need to do going forth. In past build, I addressed the rudder post in different ways. The first scratch build, Rainbow. I had to do some retro fitting and by the time I did Enterprise, I had my thought into the "what if" scenario. I guess that's what being a crafts-person it's all about. Hopefully tomorrow, I will have the planking completed and will be able to start sanding and fairing in preparation for the Kevlar/resin finish. The next week is prep week.
As a side line, anyone interested in J Class R/C boats, this year at Stowe's J Days regatta, we may have the most diversified fleet ever. The possible AC boats to attend are: Enterprise, Yankee, and Shamrock from 1930, Rainbow and Endeavour 1934, Ranger 1937, and 2 unrealized designs, Svea and Frank Paine's 1935 "A" design that was eventually built as Topaz. Should be a beautiful site.
Blog photos have been up dated.
Last edited by spinnaker225; Feb 09, 2020 at 06:42 AM.
Feb 09, 2020, 08:02 PM
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Topaz - F.Paine's 1935 "A" design


Planking is complete and sanding and fairing will be the objective for the upcoming week. Glassing may start by next weekend.
Feb 10, 2020, 07:16 PM
rshousha
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I could really use some help with my new project. I have a design for frames for Shamrock III at 102" but do not have a deck or the deck structures for this yacht. I have started a new thread on this forum here; https://www.rcgroups.com/forums/show...-in-1-16-scale

I have found very little information on what was on deck in 1903. I think there are a few large deck hatches and a single companionway opening but it would be fun to have some detailed pictures or drawings of the structures. Working in 1/16 scale allows me to design a lot of detail into the parts.

Thanks!
Feb 12, 2020, 09:42 PM
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seefest's Avatar
Quote:
Originally Posted by spinnaker225
I have used Kevlar many times and in many different applications before. If you buy the right Kevlar, it isn't that bad to deal with. I like the durable it offers. As far as sanding, all cloth gets fuzzy when sanded. the object is not to sand the cloth. The first hull I did with the CF/K hybrid cloth, I was a little aggressive with my first sanding and had to deal with a little fuzz. after the 3rd coat, it was like glass. The 4th coat was thinned and went on beautifully. The object is not to sand it to that point. 1st coat gets a minimal sanding and, it's not until the 3rd coat of resin that you really focus on thorough sanding. On my last models, (Rainbow and Enterprise) I used Carbon/Kevlar hybrid cloth instead of plain glass cloth. I have seen how easily plain cloth punctures. These models are only getting 1 layer of cloth unlike a built up mold. With the contact that happens on occasion, (I had a built up hull punctured last year) I like the idea of hedging on the side of durability. Price online is not that bad for only 3 yds. The 5.5 oz that I'm using is quite soft. Cutting Kevlar and Hybrid cloth is not a problem if you have the proper shears.
I don't just build J's because they are easy. I select models that aren't common. That's why I chose to build Frank Paine's 1935 "A" design. It has some interesting features and there isn't another out there. I look to experiment with materials, techniques and of course design choices on future builds.
Bottom line, it's my choice. At J Days in Vermont this Spring, we'll see how well my efforts pay off.
Not all cloth gets fuzzy when sanded. CF and GF cloth does not. (At least not to the extent of kevlar) Iíve worked extensively with all cloths in both full size and RC applications. Youíre right, the choice is yours and if you want to put in more work than necessary have at it.

One layer of Kevlar may keep another J from puncturing your hull, but there will still most likely be damage to the underlying planking and structure. Bottom line is youíll still be repairing your hull.
Mar 20, 2020, 01:59 PM
Registered User

Topaz - F.Paine's 1935 "A" design


Glassing done and the hull is faired and primed. She is officially free of the Tee Rail. Deck framing done, blocking in place for servo/radio boards, and sub-deck installed. Planking has started. The one sad thing that Covid-19 has thrown at us is, the Green Mountain J Day regatta is cancelled/postponed to a later date, maybe, so her maiden regatta will have to wait. New text and pics on my build blog.
Mar 20, 2020, 04:03 PM
Registered User
Very nice !
One can see you like WOOD !
Mar 20, 2020, 05:13 PM
rshousha
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Very nice work. What is the thickness of sub-deck you're using there?
Mar 20, 2020, 06:51 PM
Registered User

Topaz - F.Paine's 1935 "A" design


I lay down 5/32" balsa that has been thoroughly coated with resin on the bottom to bring the top of the bulkheads up to the level of the 5/32" perimeter at the shear. After that cures, I coat the top of the balsa with another coat of resin and then lay 1/32" sheet of plywood over lapping the perimeter. Then I lay the
planking over that. after sanding, the total deck thickness is just under 1/4" thick. This system ends up being quite light and strong.


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