Primitive Archer

Main Discussion Area => Bows => Topic started by: Nasr on August 17, 2019, 11:41:04 am

Title: how do you taper your laminations
Post by: Nasr on August 17, 2019, 11:41:04 am
 I have a dewalt planer and I have been trying to figure out how to taper laminations with it. Does anyone else use a planer or do you guys go a different route.
Title: Re: how do you taper your laminations
Post by: Badger on August 17, 2019, 11:52:33 am
If I do use my planner for tapering a lamination the way I do it is I build up tape at specific intervals just to control my taper. I would normally taper at 4 to 6000 per inch
Title: Re: how do you taper your laminations
Post by: Nasr on August 18, 2019, 12:09:25 pm
Sorry Steve can you please clarify more do you mean if you have a lamination that was 1/4 " it would taper from that to an 1/8" for 36" lamination.
Title: Re: how do you taper your laminations
Post by: Del the cat on August 19, 2019, 02:15:49 am
Here's my thicknesser/taper jig
https://bowyersdiary.blogspot.com/2017/09/more-thicknesser-development.html (https://bowyersdiary.blogspot.com/2017/09/more-thicknesser-development.html)
Del
Title: Re: how do you taper your laminations
Post by: Bayou Ben on August 19, 2019, 08:53:49 am
A thickness sander is the proper tool for making laminations.  You can buy one or make one yourself.  I made mine from a cheap 4x36" belt sander.  There's a bunch of plans floating around to make one yourself, especially from the guys making guitars.
Planers can work.  I've used them for simple backed bows and working down boards from 3/4" stock.  Dean Torres shows a method where you progressively run the piece through the planer and this works well on most wood.  The problem you have with planers is tear out on some species and it becomes unsafe to work with thin stock.  The thickness sander is more precise, it's safer, and you won't ruin wood.
As far as a taper rate, I like to shoot for the same as Steve, about 0.006"/inch total.  This will give you a nice bend for gluing and should be close to floor tillered off the form if you have a decent width taper.  In this case if I have a tri lam, I'll taper the belly, core, and backing each 0.002"/inch for a total of 0.006". 
What kind of bow are you trying to build?
Title: Re: how do you taper your laminations
Post by: Nasr on August 19, 2019, 10:05:02 am
A thickness sander is the proper tool for making laminations.  You can buy one or make one yourself.  I made mine from a cheap 4x36" belt sander.  There's a bunch of plans floating around to make one yourself, especially from the guys making guitars.
Planers can work.  I've used them for simple backed bows and working down boards from 3/4" stock.  Dean Torres shows a method where you progressively run the piece through the planer and this works well on most wood.  The problem you have with planers is tear out on some species and it becomes unsafe to work with thin stock.  The thickness sander is more precise, it's safer, and you won't ruin wood.
As far as a taper rate, I like to shoot for the same as Steve, about 0.006"/inch total.  This will give you a nice bend for gluing and should be close to floor tillered off the form if you have a decent width taper.  In this case if I have a tri lam, I'll taper the belly, core, and backing each 0.002"/inch for a total of 0.006". 
What kind of bow are you trying to build?


 I would like to build a tri laminate reflex deflex bow. I have heard about tear out with planers and laminates not being safe to run through but haven’t had any issue with either of those. I built a jig for the planer and ran some white oak and ipe through haven’t had any problems with tear out or any safety concerns. But I do have a fairly sharp set of blades in there. I a dewalt 735x and there is a setting which slows down the feed rate for smoother cuts and that I feel helps a lot.
Title: Re: how do you taper your laminations
Post by: Nasr on August 19, 2019, 10:40:08 am
also i forgot to mention that each laminate tapers .005 so not all three equal that is actually just one piece and the backing and belly laminate are parallel i don't know if that will work but we will see. This is my first tri laminate bow.
Title: Re: how do you taper your laminations
Post by: Bayou Ben on August 19, 2019, 10:48:59 am
You can certainly do it with a planer.  Jigs like Del has on his site make them more precise and safer. 

I would check the taper with a caliper to make sure it's consistent.  Hard to pick up .006" with a tape measure.  Inconsistencies stack up quickly in a tri-lam.

You will also want to rough up the surface before gluing.  Cutting blades from planers and joiners leave a smooth surface not the best for glue adhesion.       
Title: Re: how do you taper your laminations
Post by: Stick Bender on August 20, 2019, 02:26:46 pm
Here is a .005 taper sled made out of bamboo flooring for wood bows ,sleds keep every thing precise I use a thicknes sander (drum sander) conveyer feed & I ground the conveyer belt dead parallel to the drum the devil is in details with lam bows like Ben said ,but the down side of this system is you cant do full length lams with out jointing , Ben has a good system for that with his home made grinder , I tried Dean Torges jointer grind on a full length lam bamboo backed bow & cleaned up by hand and it only took about 15 min to tiller in the end , you can also make a sled for your band saw if you have one and pre cut the taper in thicker lam & spend less time grinding the taper in also saves material even with the precession of my system I will split the lams in segments and check with calipers and sand where if needed , if you take the time to make perfect lams the bow almost always hits tiller with little work !