Making wooden blocks for my mainsheet

[John Stevens]

I'd like to try to make some wooden blocks for the pram I'm building. Is there a site that would be helpful or could someone explain it?

TIA,

John

[Jan Williamson]

This is a good one

http://www.duckworksmagazine.com/articles/woodenblocks/woodenblocks.htmis

[capt jake]

That's the one I used, though it doesn't appear to be available anymore. Try Phil Gowans site, he outlines the process.

[Frank Hagan]

Guys, please be careful.

The content at Duckworks is copyrighted. Please don't post content from that site without getting permission from them first, or from the original author of the article. You can feel free to provide links to the site, but you cannot duplicate the content THERE in a post HERE. Just the way copyright law works!

If you asked, Chuck might allow it to be posted here, with links back to his site, of course. But I wouldn't want the content posted here without his permission.

[Stump]

Sorry Frank,

It was the pirate in me coming out, :oops:

[Frank Hagan]

Sorry Frank' date='

It was the pirate in me coming out, :oops:[/quote']

Not a problem; I know you were just trying to be helpful (like everyone here always is!) I have to play the heavy and be anal about that kind of thing to keep my Administrator eye-patch! :pirate:

[Jan Williamson]

Frank, I just looked at that site last week, they must have just changed it. I wouldn't have posted it had I known it was unavailable. Now I wish I would have saved it, instead of just saving the link :cry:

[Tidmarsh]

Could someone explain it?

Sure' date=' they're not too hard and look really cool.

You'll need a drill press, 1.75" hole saw, drill bits, a 6.5" round Microplane rasp, a flat microplane rasp, a jigsaw or bandsaw, a 3" #10 machine screw, nut, and wingnut, and a small scrap of 14" inch plywood.

Make the sheaves out of 1/2" UHMW polyethylene or UV-resistant VHMW polyethylene. Cut them out with the hole saw, which will give sheaves just over 1.5" in diameter. Then chuck them into the drill press using the machine screw and a couple of pieces of plywood cut out with the hole saw. Use this like a lathe, and turn a groove into the sheave with the round rasp:

[img']http://216.77.188.54/coDataImages/p/Groups/147/147689/folders/113785/795896sheaves2.jpg[/img]

Use 1/4" brass rod for the pin. You can then drill the sheaves out to 1/4", or out to 5/16" if you want to use an oilite bushing. Brass rod, 1/2" polyethylene sheets, and oilite bushings are all available from McMaster-Carr, http://www.mcmaster.com

For the bodies, the easiest way is to use a piece of douglas fir 2 x 2. You'll want a block about 3 or 3.5 inches long. Draw a curve on the top and bottom. Mark where the pin will go through; you'll want it to be offset about 3/8" off-center toward the bottom to allow the line to pass over the top. Drill a 1/4" inch hole witht he drill press.

Mark the opening for the sheave on the face perpindicular to the pin. Mortise it out by drilling a 1/2" inch hole at each end, cutting the waste with the jigsaw, and shaping and enlarging the mortise with the flat rasp.

Now use the rasps to shape the body of the block and cut a rope groove around the outside. Sand smooth.

Finish with either an oil finish or varnish, splice an eye to fit around the block, and tighten it up with a seizing of tarred marline:

Tie the tail off to the boom where needed:

[John Stevens]

Thanks, those look beautiful. Did you make your own cleats of wood also?

John

[Greg Luckett]

Try this link:

http://www.duckworksmagazine.com/s/articles/hardware/index.cfm

I am not sure if you must be logged in on the Duckworth site to get to it, but I was when I found it.

[Greg Luckett]

Do you think Delrin would work? I have not been able to find out if Delin is the sort of polyethylene you have shown being used.

Thanks,

Greg.

[Tidmarsh]

Thanks' date=' those look beautiful. Did you make your own cleats of wood also?

John[/quote']

Thank you, I made those also. I cut them out with a jig saw, rounded them with a Microplane rasp, and sanded smooth. I've been amazed at what a woodbutcher such as myself can turn out with a jigsaw, rasp, and sandpaper. Cut out the rough shape and then take away everything that doesn't look like a cleat with the rasp. Seems like it only took an hour or two to do 4 cleats.

For proportions, search for Craig O'Donnell's Cheap Pages. He lists dimensions from several sources, including Edson Schock's How to Build Small Boats, which I used. H. G. Smith's Marlinspike Sailor also has dimensions for a wooden cleat and a jam cleat.

Do you think Delrin would work? I have not been able to find out if Delin is the sort of polyethylene you have shown being used.

I don't know what type of material Delrin is, but I've heard of sheaves made from it, so it should be appropriate. Don't know how easy it is to carve, though.

You might also have a look at these sheaves:

http://www.duckworksmagazine.com/store/hardware/blocks/sheaves.htm

I'd have probably bought these if I'd had a source at the time. When I built my blocks, the cheapes sheaves I could find were ~$10 each.

[John Stevens]

Thanks,

I tried making one today and it didn't come out too bad. I traced a cleat of my Precision 18.

John