Author Topic: Here's another question about riser design...  (Read 7051 times)

0 Members and 1 Guest are viewing this topic.

Offline Easternarcher

  • Member
  • Posts: 622
Here's another question about riser design...
« on: August 29, 2007, 08:34:03 am »
On this Jatoba bow I'm working on, the rough cut riser is 1.25" wide, same as the limbs at fade.

I'm cutting in a shelf on this one, just to see how it works out. Now, question is....if I want a quarter inch shelf, how narrow can I make the grip area for a hill style riser? 1 inch? or ,maybe a bit less?? It'll draw 50 lbs at 27" .
I sure don't want to weaken the riser too much...that would not be good in failure! :o

Offline gpw

  • Member
  • Posts: 149
Re: Here's another question about riser design...
« Reply #1 on: August 29, 2007, 10:20:18 am »
East , the riser is usually MUCH thicker than the limbs so is very strong you should be able to get real close to centershot ...just don't go crazy !!!  "wood that is twice as thick is eight times as strong"

Offline Easternarcher

  • Member
  • Posts: 622
Re: Here's another question about riser design...
« Reply #2 on: August 29, 2007, 10:36:28 am »
East , the riser is usually MUCH thicker than the limbs so is very strong you should be able to get real close to centershot ...just don't go crazy !!!  "wood that is twice as thick is eight times as strong"

That's encouraging.....1.25" wide X 1.75"-2" thick riser

Offline Justin Snyder

  • Administrator
  • Member
  • Posts: 13,794
Re: Here's another question about riser design...
« Reply #3 on: August 29, 2007, 12:50:18 pm »
East , the riser is usually MUCH thicker than the limbs so is very strong you should be able to get real close to centershot ...just don't go crazy !!!  "wood that is twice as thick is eight times as strong"
Well said.  Twice as wide is twice as strong.  Twice as thick is 8 times as strong.  If your handle is twice as think as the limb, you can get 1/2 the width without any worries. BUT like GPW said, no reason to "go crazy."  Justin
Everything happens for a reason, sometimes the reason is you made a bad decision.


SW Utah

Offline Easternarcher

  • Member
  • Posts: 622
Re: Here's another question about riser design...
« Reply #4 on: August 29, 2007, 01:32:45 pm »
East , the riser is usually MUCH thicker than the limbs so is very strong you should be able to get real close to centershot ...just don't go crazy !!!  "wood that is twice as thick is eight times as strong"
Well said.  Twice as wide is twice as strong.  Twice as thick is 8 times as strong.  If your handle is twice as think as the limb, you can get 1/2 the width without any worries. BUT like GPW said, no reason to "go crazy."  Justin

So, if I narrow the overall width of the riser at the grip to say....7/8", I can go even deeper without problem as long as the thickness of the riser reamins the same??
Interesting.

Offline Justin Snyder

  • Administrator
  • Member
  • Posts: 13,794
Re: Here's another question about riser design...
« Reply #5 on: August 29, 2007, 02:55:44 pm »
Is it a glue on riser? If it is you need to pay attention to the thickness without the glue on.  Sometimes risers will pop off if there is any flex in it.  How about some pictures.  Justin
Everything happens for a reason, sometimes the reason is you made a bad decision.


SW Utah

Offline Easternarcher

  • Member
  • Posts: 622
Re: Here's another question about riser design...
« Reply #6 on: August 29, 2007, 03:27:22 pm »
Justin, it is a glued-on riser, but the belly wood also increases in thickness under the riser section to almost 1/2".



you can also see a bit of it here with the bow strung.


riser isn't final shape yet, I may taper the fade more to reduse the actual grip length.

Offline Justin Snyder

  • Administrator
  • Member
  • Posts: 13,794
Re: Here's another question about riser design...
« Reply #7 on: August 29, 2007, 05:28:04 pm »
I think you could go down in width and go to near center shot and still have no problems with that set up. If you go to 7/8" I would probably keep the shelf 3/8 or smaller.   Justin
Everything happens for a reason, sometimes the reason is you made a bad decision.


SW Utah

Offline gpw

  • Member
  • Posts: 149
Re: Here's another question about riser design...
« Reply #8 on: August 29, 2007, 07:53:14 pm »
On the other hand ... we 'primitive " guys shoot off our knuckles with properly spined arrows...got the scars and callouses to prove it ... ::)

Offline Easternarcher

  • Member
  • Posts: 622
Re: Here's another question about riser design...
« Reply #9 on: August 29, 2007, 08:48:09 pm »
On the other hand ... we 'primitive " guys shoot off our knuckles with properly spined arrows...got the scars and callouses to prove it ... ::)

LOL...GPW, yeah I've done that and thought I'd give a rest a go.... :D
Too late anyhow, I already got it started.

Offline Marc St Louis

  • Administrator
  • Member
  • Posts: 7,877
  • Keep it flexible
    • Marc's Bows and Arrows
Re: Here's another question about riser design...
« Reply #10 on: August 29, 2007, 09:27:00 pm »
A problem I have run into when narrowing the shelf to much is the handle flexing sideways.
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline Justin Snyder

  • Administrator
  • Member
  • Posts: 13,794
Re: Here's another question about riser design...
« Reply #11 on: August 29, 2007, 09:35:26 pm »
If you want a shelf, narrow everything else and leave the shelf a little wide.  You can always do a floppy rest to keep from hurting your hand.  Justin
Everything happens for a reason, sometimes the reason is you made a bad decision.


SW Utah

Offline mullet

  • Global Moderator
  • Member
  • Posts: 22,909
  • Eddie Parker
Re: Here's another question about riser design...
« Reply #12 on: August 29, 2007, 10:12:37 pm »
   I do like Justin does with a handle like yours.I mark the rest area and leave that wood alone.I then shape the handle around the shelf.Then you can cut your shelf in as needed.That way you have an idea how far you need to go.
Lakeland, Florida
 If you have to pull the trigger, is it really archery?

Offline gpw

  • Member
  • Posts: 149
Re: Here's another question about riser design...
« Reply #13 on: August 30, 2007, 09:38:18 am »
Best idea is to leave more wood than you think you need ...overbuilt at the handle not only makes the handle safer, but increases the mass difference between the handle/tips.. resulting in less hand-shock ...that's always a good thing...
 Our current favorite shelf is a piece of 1/4'buffalo hide , rounded across the top so the arrow only touches a small spot, just wrapped into the handle with a nice piece of leather(grip)...easy , no scars ... ;D