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Glassed ELB

Started by Buggs, August 19, 2022, 10:58:16 AM

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onetone

Agree, a narrow arrow pass is preferable.

Buggs

Did some more work on the bow. Got the belly fully D shaped and it was still too stout!
I left the Maple back fat to have material to remove. Having pre-tapered the lams, I knew once the side profile and D shape were established, tillering and weight reduction was going to happen on the back, mostly.
[attachment=1]
Been taking .040" off at a time. I also can trap the belly side a little bit. I am taking it slow and walking away after every step. Never tillered from the back before! The other funky factor is the floor tillering. This bow is not intended to be drawn in its unbacked state. I am worried about bending it too far and splintering some runout grain.
I'm thinking its around 60# right now. Want to get it down to around 40# or so. I don't know how much draw weight the glass sleeve will add?
Ooo, who, who hangs free

Mad Max

#42
Just asking
Why can't you tiller the belly?
A block of wood concave shaped like the belly with sandpaper on it.
I was at the Tennessee classic one year and a guy had a sanding block like that for finishing the tiller.
I hope you hit your weight  :thumbsup:
I would rather fail at something above my means, than to succeed at something  beneath my means  
}}}}===============>>

Kirkll

I'm not very experienced at building many board bows, but I've always assumed the tillering should be done after the backing.I would think That the backing is going to add draw weight and will throw the tiller off. Am I wrong about that?

What kind of backing are you using?   Kirk
Big Foot Bows
Traditional Archery
bigfootbows@gmail.com
http://bigfootbows.com/b/bows/

Buggs

#44
Quote from: Kirkll on September 07, 2022, 10:42:30 AM
What kind of backing are you using?   Kirk

Short attention span?  I'm using fiberglass sleeve.

So I could tiller the belly, but since it's pre-tapered and the bow is unglassed at this point, I would be risking a terminal failure if the belly is reduced to much, as it's being tillered.
The sleeve will certainly add some weight, how much is unknown. Considering the nature of the reinforcement, it should provide consistent and modulated strength along the length of the limbs. Of course this is all speculation if this has never been done before ;)
Ooo, who, who hangs free

Pat B

It looks to me the maple backing it way too thick. I didn't see how thick it is but 1/8" or a little less is usually plenty for most wood  backings. Also, I don't use FG on bows but I would imaging that by adding the FG sleeve you will be adding considerable weight. I guess the only way to find out is to do it. You might do a test with a section of glued up woods and test the bend before and after the FG is added.
Make the most of all that comes and the least of all that goes!
TGMM Family of the Bow

Mad Max

#46
I was meaning before the glass is put on.
I don't know anything about that kind of bow.
You have a hard challenge for yourself   :thumbsup:
I'm having a hard time texting on my phone today, I use my laptop mostly
I would rather fail at something above my means, than to succeed at something  beneath my means  
}}}}===============>>

Mad Max

I forgot to ask about that fancy tool.
That's for scribing lines?
I would rather fail at something above my means, than to succeed at something  beneath my means  
}}}}===============>>

Shredd

   Maybe I missed reading something or misread something, but what are you trying to accomplish by using this f/g sleeve?? Is it this torsion box thing?? Are you hoping for added performance or something along that nature??  Do you know there is a chance the fibers will fracture or separate and turn white when the bow is flexed??  Do you also know that the sleeve will be adding a good bit of weight to the limbs??

Just my 2 cents...

  In any account I suggest you add at least a 3/16" radius to any corners so that the glass lays flat...


Buggs

The Maple backing is way too thick. By design, thats how I'm reducing weight.

The fancy tool is a fine adjust marking gauge wheel, makes it easy to see and feel when I've removed a tiny bit.

I am trying to accomplish something new and different. Why? Why not! I'm using the F/G sleeve because I could not think of another way to glass the "D" shaped belly. There is a good chance that all those things and more could happen. Only one way to find out. It's kind of fun venturing into the unknown.

My original idea, and one that I might revisit, is to glass with the sleeve, grind off the back portion and reglass with some uni. As of right now there is no established protocol to follow, so everything is on the table!
Ooo, who, who hangs free

Shredd

10-4...   Hope it all works for yah...

Kirkll

Quote from: Buggs on September 07, 2022, 10:56:39 AM
Quote from: Kirkll on September 07, 2022, 10:42:30 AM
What kind of backing are you using?   Kirk

Short attention span?  I'm using fiberglass sleeve.

So I could tiller the belly, but since it's pre-tapered and the bow is unglassed at this point, I would be risking a terminal failure if the belly is reduced to much, as it's being tillered.
The sleeve will certainly add some weight, how much is unknown. Considering the nature of the reinforcement, it should provide consistent and modulated strength along the length of the limbs. Of course this is all speculation if this has never been done before ;)


Oooops!  Guilty as charged with the backing question.

It will be interesting to see your exact weight gain after putting this  glass sleeve on it. I think you will be looking at about 30% increase. A 40# bow will become 60#, and your current 60#, a 90#....

Keep us in the loop on this. I'm curious how it goes.   Kirk
Big Foot Bows
Traditional Archery
bigfootbows@gmail.com
http://bigfootbows.com/b/bows/

Buggs

Glass sleeve came in the mail today. Nice and thin. Should not wet out to more than .020" and I will loose some of that thickness during smoothing.
[attachment=1]

Another interesting property of this biaxial sleeve is that it can be effectively pre-tensioned.

Ooo, who, who hangs free

mmattockx

Quote from: Kirkll on September 07, 2022, 02:33:05 PM
It will be interesting to see your exact weight gain after putting this  glass sleeve on it. I think you will be looking at about 30% increase. A 40# bow will become 60#, and your current 60#, a 90#....

Umm, 40# to 60# and 60# to 90# are both 50% increases, not 30%... That aside, I am also interested in seeing what adding the sleeve does to things.

Buggs, what are you using for the resin? Make sure you take some pictures of how the bow core is bending before you add the sleeve and then the same after the sleeve is on.


Mark

Kirkll

Well in my head I was thinking in thirds.... 20,40, 60 but screwed up the percentage increase.  :dunno: :knothead:

Shredd has a bunch of glass experience that I've never dabbled in. His estimate would most likely be much closer than mine.  I've still got a few sticks of his colored glass he laid up years ago that I've never used that I'd be willing to give to to someone that wants to play with it... it's a wild looking electric green color.


Kirk

Big Foot Bows
Traditional Archery
bigfootbows@gmail.com
http://bigfootbows.com/b/bows/

Buggs

Mark, this is a description of the epoxy I will be using;[attachment=1]

Kirk, I am wondering how you came up that 30% figure, not knowing the thickness of the fabric and resulting laminate layer?
Ooo, who, who hangs free

Kirkll

Quote from: Buggs on September 08, 2022, 09:39:57 AM
Mark, this is a description of the epoxy I will be using;[attachment=1,msg3011301]

Kirk, I am wondering how you came up that 30% figure, not knowing the thickness of the fabric and resulting laminate layer?

My ball park 30% comes from building a lot of glass backed bows. Sanding glass reduces draw weight about 1# for .002 of glass.  on a 40# wood bow adding .040 worth of glass would give you an additional 20#.... Plus... this glass runs around the sides too.... It may be more than that....Who knows?

You will find out soon enough... I'll be curios....    Kirk
Big Foot Bows
Traditional Archery
bigfootbows@gmail.com
http://bigfootbows.com/b/bows/

Buggs

I have been considering what to do for the nocks on this bow. I have some nice Horn[attachment=1]

But since its not traditional ELB, I was thinking non trad tips might not look too funky. I keep seeing pictures of dyed Tagua nuts and really like the colors, so I got some good old Rit dye at the grocery and commenced to experimenting.
[attachment=2]

It works real good!
I was wanting a Jade color, but they only had a few color options locally. Rit has a formula chart for all kinds of colors, so I should be able to get close to the green I want. I did a hot dye bath in the mini Crock pot. Soaked for an hour and then added some washing soda to fix the color and let that soak for another hour. Then it got dropped in a bucket of detergent water and soaked over night. Almost no color came out in the final soak.
Here is a before pic.[attachment=3]
Lots of tool marks, no point to polishing it before this. Carved, polished and dyed, I think it could make some cool looking tips.


Ooo, who, who hangs free

Buggs

Quote from: Kirkll on September 07, 2022, 09:45:25 PM
it's a wild looking electric green color

You got any close up pics, Kirk?
Ooo, who, who hangs free

Kirkll

Here is that green glass Shredd laid up years ago.  it's .060 -.065 and seriously heavy in weight. If this is what he was using building bows it's no wonder he was struggling to get 190 FPS out of his testing. I have no use for it myself and would gladly send it to you Buggs.... btw... its 1.5" X 38.5"

[attachment=1][attachment=2]
Big Foot Bows
Traditional Archery
bigfootbows@gmail.com
http://bigfootbows.com/b/bows/

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