Trad Gang
Main Boards => The Bowyer's Bench => Topic started by: AKmud on November 08, 2010, 09:38:00 PM
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What is the secret to making smooth arcs on a bow form?
Today was my first attempt at making a R/D form. I started with a sheet of 3/4" CDX. I ripped it in half then screwed/glued the two halves together to get a 1 1/2" thick piece to work with. I cut it down to 72" then laid out the design.
I bought a 8' stick of 1/8" x 1 1/2 aluminum to line the surface of the form. I used this piece to create the curves for the form as well. I put nails in strategic spots to make the R/D shape with about 3" of deflex (from the back)ending with about 1" of reflex at the tips (forward of the back).
I took my time and cut out the form with a high quality saber saw leaving the line to dress up with a drum sander on the drill press. This is where I wasn't very satisfied...
I made sure the table was square with the sander and slowly brought the edge to the line. I squared it up in a few spots with a hand sanding block and mounted the aluminum strip with countersunk screws. Standing back looking at the lines, it isn't quite as perfect as I would like. I notice a very slight flat spot on one of the curves and have tried loosening a couple screws and playing with the strip to get things bending better but I'm not sure I will make any progress without shimming the strip.
Am I missing any steps here or are there any secrets for making great lines??
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Here is the best way I've found, much easier to get smooth flowing lines on a pc of 1/4" as a template than 1.5 or 2" thick.......
http://kennyscustomarchery.com/Bow_forms.html
Hope this helps some.
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Like Kenny says. Do what you did to make the lines, but on a piece of something like 1/4" hardboard. (masonite or something) Much easier to tweak that until perfect then use that for your guide for the pattern cutting bit.
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Thanks for the info guys. Kenny I did peruse your site before trying this but I somehow missed the 1/4" pattern.... I might grab a piece and overlay it on my form and try again. I have some wiggle room since the form is 24" bottom to top.
Do my dimensions sound about right 3" negative returning to 1" positive over 72" form?
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24"? :eek: Man, you better have yer wheaties before puttin that in the heatbox!! :D
The d/r rate sounds pretty good too.
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Yeah....not really sure what I am doing so I just took a sheet of 3/4" CDX and ripped it in half. What are typical dimensions of a form?
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My 64" d/r requires a 1.5 x 12 x 72 form blank.
I just try to have at least 4" of form in all the dips....
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Thanks Kenny, I think I'll pull some screws and make some modifications.