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Emma56
10-21-2006, 07:23 AM
Hello Does anyone have experience with foundry patterns ? I have made a set of floor patterns [ like Larry Pardey made for Taleisin. ] He constructed his with 1/4 ply. One foundry commented that seemed a bit thin to cast. The problem that I have is the ply doesn't stay flat! I made a few with 1/2" and they looked fine. Is that too thick/ To much weight ?

Emma56
10-21-2006, 07:55 AM
MDF That sounds like the ticket , thanks Jim

mmd
10-21-2006, 08:01 AM
Yes, I have worked with foundries to create ship parts before. A question for you, if I may: Mr. Pardey had a specific reason for installing bronze floors in Taleisin; why are you selecting this expensive and labour-intensive method over fitted wood floors? Quarter-inch castings should not be a problem for a good foundryman. If your plywood won't stay flat, get better plywood or use a different material. The thickness/weight of the floors should be determined by the strength required of the finished floor, not dictated by the pattern material. The idea is to have adequate strength with minimum weight, regardless of the material. If you continue with this plan, be sure to allow for casting shrinkage when you make your patterns, and think carefully about how you will fasten them to your boat's wooden structure.

Emma56
10-21-2006, 08:19 AM
Yes I will use wooden floors for the engine beds . Have started them. As for metal floors I liked the extra headroom they would allow, And they also have a direct connection to the lead ballast. Also the arm length over the ballast is 18" Do you think that wood plank floors would be as strong? Maybe this approach is folly This is my first boat !!!

Emma56
10-21-2006, 08:41 AM
I have two sets of plans . One with wood floors and one with metal floors [Taleisin] I just checked the headroom measurement , Off the wood version. Only the forward area ahead of the mast would change. I'm starting too like the thought of Wood floors. I have the wood on hand ! And could start them As opposed to saving up money to have them cast Thank guys

kc8pql
10-21-2006, 08:55 AM
Only the forward area ahead of the mast would change.

I guess the question is if a few more inches of headroom in an area that doesn't have standing headroom anyway worth several thousand dollers. I'd save my money for later, when the real expense starts.

Emma56
10-21-2006, 09:14 AM
Thanks Guys I Love this place !!!!!

Jay Greer
10-21-2006, 09:21 AM
Although I was around the shop when Larry Pardy made made up his floor patterns for "Taleisin", I don't recall what grade of ply wood he used. I do know that they were coated with shellac and did not warp.
This was partially due to the fact that the web flanges prevented any movement of the wood. I personaly prefer bronze as a material for floors. They take up less space, and offer better drainage and ventelation to the bilge and impart greater strength to the ballast keel attachment. My own method imparts a flat wing that runs up the molded inner surface of the frames. This adds a bit more strength as well as progressive flex to the frame, there by discouraging frame cracking just above the floor tops. It also allows laminated frames to be used as well as the use of bronze machine screws through the planking, frame and then threaded through the floor wings. Essentially this is a variation of keel strapping and has proven to be quite successful.

Jay Greer
10-21-2006, 01:15 PM
Searover,
I offer my appologies for adding too much to this thread. When Larry and I started making patterns, neither of us had done much foundry work before. We did learn by doing. Sure, we made mistakes, but we learned from them. Often a mentor is needed for this kind of work. I do feel that, today, one would be hard pressed to go and search for a better source of assistance than can be found in this forum
Fair Winds,
Jay

Jay Greer
10-21-2006, 02:47 PM
Jim,
Most of my photos are slides that are not with me here. I will be sorting through them this winter when I get back to Port Townsend.
Jay

Canoeyawl
10-21-2006, 03:10 PM
I noticed at Joel Whites shop (Brooklin Boat Yard) they made bronze floors basically in situ by welding bronze plate.
They could be cut with a band saw, drilled for fasteners, tacked together in place, then removed and welded complete. This would be about the same amount of work as making the patterns. You just need to spring for the bronze plate instaed of plywood! I think that ¼ inch may be heavier than you need for the gusset pieces. Maybe the piece that the keel bolt goes through but that may be it. A little math would be good here and could save a quite a bit of money.
A good welder with mobile MIG equipment would make short work of this…

Emma56
10-21-2006, 05:08 PM
Here is a shot of my floor patterns . I picked them up off my lofting http://i84.photobucket.com/albums/k33/BSaDP/DSC00078.jpg

Emma56
10-21-2006, 05:28 PM
I will send a shot of the finished parts tomarrow , Going out to the movies with the girl friend to night [ The new Clint eastwood film ]

Bob Cleek
10-21-2006, 10:17 PM
Maybe Jay can elaborate a bit regarding Larry Pardey's floors. I've studied that chapter dozens of times and I still can't figure why he didn't weld or braze them up out of sheet stock. Maybe it was the price of sheet stock? As for casting, though, it really isn't all that big a deal. We often forget there's a lot of metal in a wooden boat. Back in the days of wooden ships and iron men, they made their own metal work same as they did the wooden parts. There's precious little attention paid to preserving the metal working crafts, even though the "wooden boat rennaisance" seems to have saved the woodworking crafts in large part.

I've been researching the machinist trade, since I haven't been able to find parts and so on. Got me a decent Atlas lathe and tooling. Next step is going to be finding a smelting furnace and playing with some castings. There is a lot of this going on on-line, but most of the guys doing their own metal work are into building steam trains, not boats.

http://www.steamingpriest.com/media/american/am-ride.gif

http://www.steamingpriest.com/media/american/am-13.gif

Fascinating hobby and amazing workmanship:http://www.steamingpriest.com/