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Old Jan 02, 2013, 07:52 AM
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Hot wire cutter question

I am using a gravity-feed hot wire cutter similar to the Feather/Cut system. I have read in sevaral places that weights may need to be placed at the ends of the bow cutter legs, where the hot wire connects, to aid in cutting the leading edge concave cut on the lower airfoil. My question is: How heavy are weights that are used here?

Thank you for your time.

Ed
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Old Jan 02, 2013, 08:25 AM
Red Merle ALES
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United States, Mt, Helena
Joined Apr 2002
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Ed,

I don't use or rely on the weights. When cutting the bottom part of the airfoil I apply down pressure with my hand till the hot wire gets to the lowest part airfoil then release.

When I cut the top part of the airfoil I accomplish this by hand as well and slightly lift the wire upward then release.

In both cases I allow the weight on the swing arm to pull the wire aft.

I'm sure someone else will help with what weights to use.

Curtis
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Old Jan 02, 2013, 08:35 AM
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Curtis...
Thank you for the reply.
I have done the same thing myself. But, I have had a couple instances where the right hand doesn't know what the left hand is doing, and I get a good cut on one end, and a bad one on the other. I thought I would try the weights, just to see if it's easier for me.

Ed.
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Old Jan 02, 2013, 09:18 AM
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It depends on how you have your bow positioned. The gravity-feed system will be pulling the wire forward (and only very slightly down), so something else needs to provide some downforce to keep the bow on the template. For bottom template cuts, I have my bow hanging from the ceiling, something like what you can see in http://www.monkeytumble.com/dlg/imag...ceiling_01.jpg . This setup naturally provides weight to keep the bow on the template, and makes my bottom template cuts 100% hands-off.

Now getting the bow to go up the ramps at the start of the top template cut... that's another story. I still don't have a worry-free way to make that happen perfectly every time.
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Old Jan 02, 2013, 09:42 AM
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Mark...
Thank you for your reply.
It looks like you don't use weights at all. I also have my bow suspended from the ceiling, but not at the angle you have. Mine is lower. I'll try raising it up more, and see what happens.
I don't have a problem with the top cuts. I may have to give the wire a nudge to get it going, but then it goes up and over. Perhaps that is due to my lower angle not putting as much down-pressure on the top cuts.

I would still like to hear what those that use weights are putting on their bows.
Thank you.

Ed
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Old Jan 02, 2013, 06:29 PM
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My Feather Cut bow came with 4 ounce " Egg" fishing weights, that were drilled out to fit the steel legs.

You still needed to guide them at the start of the cut.

Now that I make my own bows , sometimes I'll use a couple ounces of lead on the legs next to the wire.

But the thing that has helped me the most is " lead in" ramps on the templates. Since the wire is already diving or climbing all that is needed is some gentle guidance with your index finger.

Blue Skies................................Tim
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Old Jan 02, 2013, 06:57 PM
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Thank you all for your suggestions.

Tim... I'll try your weights and lead-in ramps.

Ed
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