Primitive Archer
Main Discussion Area => Bows => Topic started by: DC on March 19, 2019, 12:04:21 pm
-
In the picture the black line is an arc of a circle. Assume it's a pyramid limb so theoretically it is the same thickness all over. Now let's make a Molle. Cut it off and splice on a lever. The red line is the lever. If I push on the end of the lever with the same force as we used for the full limb does the shorter section of the arc still retain the circular, pyramidal, even thickness properties? I'm thinking yes but there's a lot smarter people out there than me.
-
DC –
For the Mollie design, if you pull the tip of the RED line even with the tip of the BLACK line, the working portion of the limb will be under more strain. So, adjustments need to be made to maintain the draw length: 1. wider & thinner working limb, 2. Longer working limb, 3. Thinner limb & lower draw weight.
That’s the fun part of Mollies…lots of options.
-
Not sure if this is a help,but this is what I go for in a pyramid mollegebet self bow
-
grouse tiller shot bush. I'm struggling through a molly at the moment and that photo will help.
-
In the picture the black line is an arc of a circle. Assume it's a pyramid limb so theoretically it is the same thickness all over. Now let's make a Molle. Cut it off and splice on a lever. The red line is the lever. If I push on the end of the lever with the same force as we used for the full limb does the shorter section of the arc still retain the circular, pyramidal, even thickness properties? I'm thinking yes but there's a lot smarter people out there than me.
Assuming both are the same thickness and width, if you pull both with the same amount of pressure, the Molly will bend further, with a tighter radius. If your goal here is to have the tips end in the exact same spot under the exact same draw weight, then you need to make the Molly wider, and thicker. Thickness will increase its bend radius and bring the tip up to meet the pyramids tip, the extra width will compensate for reduced working limb mass and allow you to keep the draw weight the same.
-
You guys aren't quite answering the question I asked. I probably asked it wrong. I'm just wondering if a section of a pyramidal limb will still bend in a circular way? Rather than elliptical.
-
You guys aren't quite answering the question I asked. I probably asked it wrong. I'm just wondering if a section of a pyramidal limb will still bend in a circular way? Rather than elliptical.
Yes
-
The whole elliptical versus circle is a bit silly. A circle IS an ellipse. It's all a matter of degree and shape of bend.
-
The whole elliptical versus circle is a bit silly. A circle IS an ellipse. It's all a matter of degree and shape of bend.
Its more of a rectangle than a square really...
-
Yeah, I was just wondering if the shape would change with the straight outer limb.
-
Yeah, I was just wondering if the shape would change with the straight outer limb.
Nope, with the shape being a pyramid limb, you want its bend to look exactly like an otherwise full pyramid bow woukd look like.
-
Yeah, I was just wondering if the shape would change with the straight outer limb.
Nope, with the shape being a pyramid limb, you want its bend to look exactly like an otherwise full pyramid bow woukd look like.
It has to bend more though, no? The lever is not bending so something else needs to bend more.
-
Yeah, I was just wondering if the shape would change with the straight outer limb.
Nope, with the shape being a pyramid limb, you want its bend to look exactly like an otherwise full pyramid bow woukd look like.
It has to bend more though, no? The lever is not bending so something else needs to bend more.
Yes it bends more. But more than what? A lomger bow tip to tip? Yes. A shorter bow? Maybe not, and even shirter, probably not. But my point was, you dont make that happen by just making it thinner. And we have already gone into the thickness and width discussion.
-
I can see that it has to bend more. At least to get the draw length.