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Main Boards => The Bowyer's Bench => Topic started by: mydog'sslave on November 18, 2012, 01:26:00 AM

Title: Any suggestions about the thickness of lams?
Post by: mydog'sslave on November 18, 2012, 01:26:00 AM
I plan to make a 62"reflex/deflex bow. I have seen them about 1.25" wise tapered to the tip and that's how I plan to make one.  Bingham's directions are for wider limbs.  I plan to use the action bamboo and any guess I would make would probably be disastrous since this will be my 2nd bow. Any help would really be appreciated.
Title: Re: Any suggestions about the thickness of lams?
Post by: mydog'sslave on November 18, 2012, 01:27:00 AM
I forgot to add that I want the bow to be about 50 pounds......
Title: Re: Any suggestions about the thickness of lams?
Post by: jsweka on November 18, 2012, 06:52:00 AM
It's kind of hard to give you real sound advice because it depends on how radical of a r/d design you build.  I'm not familiar with the Bingham's r/d design.

Here's the recipe for a 62" mild r/d I built about a year ago that might help you out, but you might need to build one and then adjust accordingly for your given design.

Brown glass back - 0.040
Hard maple 0.002 taper - 0.090 butt thickness
Hard maple 0.002 taper - 0.090 butt thickness
Hard maple parallel -    0.060
Hard maple parallel -    0.060
Brown glass belley - 0.040

Total stack = 0.380
Total wood = 0.300

The bow was 1 3/8" wide at the fadeouts and came in at 47# @ 28".

(http://i954.photobucket.com/albums/ae23/jsweka/ReflexDeflex/CAM_2095.jpg)

(http://i954.photobucket.com/albums/ae23/jsweka/ReflexDeflex/CAM_2101.jpg)

If your's comes out heavy, you can trap the back (or belley) to reduce weight.  I once made one that came in heavy and I dropped it 10# by trapping.
Title: Re: Any suggestions about the thickness of lams?
Post by: Roy from Pa on November 18, 2012, 07:49:00 AM
47# is on the heavy side for you, isn't it Johnny Boy? :)
Title: Re: Any suggestions about the thickness of lams?
Post by: kennym on November 18, 2012, 12:09:00 PM
I'd say go with Jsweka's advice.

But, he has .004 total taper and I think Binghams has .002

I'd call them and ask their recommendation, they will help you out, and they have more data on their design than anyone!  :)
Title: Re: Any suggestions about the thickness of lams?
Post by: mydog'sslave on November 18, 2012, 12:10:00 PM
I thought that design would have a lot to do with it. Your bow looks just about how I envisioned mine to look.  Thanks for the info.  I'll be sure to keep this stuck away in my files.
Title: Re: Any suggestions about the thickness of lams?
Post by: jsweka on November 18, 2012, 03:09:00 PM
QuoteOriginally posted by Roy from Pa:
47# is on the heavy side for you, isn't it Johnny Boy?  :)  
Ha ha...That was my first r/d and I missed weight a bit, but my son, Monkeyboy, inherited his Dad's strength and is shooting it now.

(http://i954.photobucket.com/albums/ae23/jsweka/ReflexDeflex/CAM_2094.jpg)
Title: Re: Any suggestions about the thickness of lams?
Post by: Dan Bonner on November 18, 2012, 03:36:00 PM
I second that assuming you are building a .04 taper rig. I build one with a little more pronounced RD and .380 would put you real close to 50# on mine. Thats with a 21" riser and a very narrow limb profile with 6" tip wedges.
Title: Re: Any suggestions about the thickness of lams?
Post by: Dan Bonner on November 18, 2012, 03:41:00 PM
I second that assuming you are building a .04 taper rig. I build one with a little more pronounced RD and .380 would put you real close to 50# on mine. Thats with a 21" riser and a very narrow limb profile with 6" tip wedges.
Title: Re: Any suggestions about the thickness of lams?
Post by: mydog'sslave on November 19, 2012, 11:30:00 AM
You guys are great, thanks for the info.  I hope to be starting this soon.