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Main Boards => The Bowyer's Bench => Topic started by: Doods70 on May 28, 2014, 06:32:00 AM

Title: Increase draw weight
Post by: Doods70 on May 28, 2014, 06:32:00 AM
Greetings.

I hope this is the right forum to ask this. I have a PSE snake bow which I shoot barebow using a mongolian thumb release.

It is only 22 lbs and I hoped to increase the draw weight. Would anyone here point me to a site that shows how I can laminate this with some fiberglass tape?? or something...anything that can increase draw weight to 30-32 lbs.

Thank you so much
Doods
Title: Re: Increase draw weight
Post by: snapper1d on May 28, 2014, 09:46:00 AM
You could pike with out adding the ugly tape to it.I cant remember the formula right now and it on the other computer thats down at the moment.Someone here will have it.You may do a search on Piking Formula and find it.
Title: Re: Increase draw weight
Post by: snapper1d on May 28, 2014, 09:50:00 AM
Well I guess I lied I did have it on this computer so here it is.

 EXAMPLE:
The bow is 68" long,45 lb.@ 28",you want 55 lb @ 28"
 
 55lb divided by 45 lb = 1.22(1.22%)
 Lose the 1 (100%)
 0.22 divided by 5 = 0.044
 0.044 x 68" = 2.99"
 2.99" divided by 2 = 1.495
 So take 1.495" (almost 1 1/2") off each end.

 To find out what a given reduction in length will produce:
 EXAMPLE: The bow is 68" long,45 lb. @ 28",you only want to take of 2" (1"
 off each end)
Take off  2" for a 66"bow
                                                                                       Short Way
 1" x 2 = 2"                                                                      66" = 1.145 x lbs
 2" divided by 68" =0.029                                              64" = 1.295 x lbs
 0.029 x 5 = 0.145 (14.5%)                                           62" =  1.440 x lbs
 Add 1 (100%) for 1.145 (114.5%)                               60" = 1.590 x lbs
 1.145 x 45 lb =51.525 lb (just over 51 1/2 lb)

Take off 4 " for a 64" bow              

4" divided by 68" =.059
.059 x 5 = .295
Add 1 for 1.295
1.295 x 45lb = 58.275

Take of 6" for a 62" bow

6" divided by 68" = .088
.088 x 5 = .44
Add 1 for 1.44
1.44 x 45lb = 64.8

Take of 8" for a 60" bow

8" divided by 68" = .118
.118 x 5 = .59
Add 1 for 1.59
1.59 x 45lb = 71.55
Title: Re: Increase draw weight
Post by: inksoup on May 28, 2014, 11:45:00 AM
re: snapper...

this was very helpful thank you.

i know i was not alone...
Title: Re: Increase draw weight
Post by: inksoup on May 28, 2014, 11:49:00 AM
and ...
you can also add 2-3mm lam on the belly side of the bow. that will increase the bow weight as well. but i don't know how much? i think it depends on the lam type (oak, hornbeam, etc...).

good luck
Title: Re: Increase draw weight
Post by: snapper1d on May 28, 2014, 03:51:00 PM
I used to sell tons of wood bow blanks and helped people get good bows from them.Most newbee's will end up under weight on their first bows and by using the piking formula they can still get a decent bow.It make a difference in one standing in the corner to look at and one you can go out and shoot and even get some game with on your first try.A good bow on the first try makes real interest in bow making.Its something that should be passed along or it will be a dying art and lost for ever.
Title: Re: Increase draw weight
Post by: Doods70 on May 29, 2014, 08:55:00 PM
Everyone seems to be in agreement on the piking of the bow. Since I am new...I am assuming that means cutting it based on the formula above.

I may have forgotten to mention that the PSE snake is a composite bow..."plastic". Will the piking work on all bows of just wood bows?

Thank you again.
Title: Re: Increase draw weight
Post by: snapper1d on May 29, 2014, 09:07:00 PM
It will pretty much work on anything.
Title: Re: Increase draw weight
Post by: Mad Max on May 29, 2014, 10:32:00 PM
QuoteOriginally posted by snapper1d:
Well I guess I lied I did have it on this computer so here it is.

 EXAMPLE:
The bow is 68" long,45 lb.@ 28",you want 55 lb @ 28"
 
 55lb divided by 45 lb = 1.22(1.22%)
 Lose the 1 (100%)
 0.22 divided by 5 = 0.044
 0.044 x 68" = 2.99"
 2.99" divided by 2 = 1.495
 So take 1.495" (almost 1 1/2") off each end.

 To find out what a given reduction in length will produce:
 EXAMPLE: The bow is 68" long,45 lb. @ 28",you only want to take of 2" (1"
 off each end)
Take off  2" for a 66"bow
                                                                                       Short Way
 1" x 2 = 2"                                                                      66" = 1.145 x lbs
 2" divided by 68" =0.029                                              64" = 1.295 x lbs
 0.029 x 5 = 0.145 (14.5%)                                           62" =  1.440 x lbs
 Add 1 (100%) for 1.145 (114.5%)                               60" = 1.590 x lbs
 1.145 x 45 lb =51.525 lb (just over 51 1/2 lb)

Take off 4 " for a 64" bow              

4" divided by 68" =.059
.059 x 5 = .295
Add 1 for 1.295
1.295 x 45lb = 58.275

Take of 6" for a 62" bow

6" divided by 68" = .088
.088 x 5 = .44
Add 1 for 1.44
1.44 x 45lb = 64.8

Take of 8" for a 60" bow

8" divided by 68" = .118
.118 x 5 = .59
Add 1 for 1.59
1.59 x 45lb = 71.55
what what what
Jethro Bodine can't figure that out   :knothead:    :laughing:    :laughing: