Giving it a shot... My First Laminated Glass Bow Build

[Major Boothroyd]

I didn't mean to give the impression that I put the form in the hot box during the dry fit.  I did not do that the first time I tried a dry fit, nor would I do that ever.  I had put the form (empty and not even bolted together) in the box to see what stabilizing effect that would have on the temperature as a test... a separate test from the dry fit.

The Eucalyptus burl veneer just seemed to dry out a little and warp in spots, when I was gluing up the scarf joints.  The joints seem perfect, but the burl has just curled slightly in a couple of areas.  I don't think it's too severe, so I'm not going to worry about that too much.

I sanded the form and the fiberglass strip carefully, and really only removed the gummy residue, and the form is still square (90deg from top to sides all the way through).

 

Originally posted by Shredd:
After all that sanding you better make sure your form is true...  Meaning fluid curves, Perfectly flat across and 90 degrees to the side...  Any slight deviations will be multiplied as you go further down the limb...  meaning you might end up with a twisted limb...  
   The dry fit does not need to go into the hotbox...  those extreme temps and humidity changes will mess with the wood...  Also when you do a dry fit anything that goes wrong, you want it to go wrong during then and not when you are gluing up...  If you are unsure about your scarfs, cut and reglue them or take the chance...  Sometimes taking an extra 10- 15 minutes is better than risking the quality of your bow...
   
   HOT BOX....

   In 85 to 90 degree temp I use 2- 70 watt bulbs and that will bring me up to 150 - 160 degrees...  Put a third bulb on for 45 minutes or so to get you up to temp quicker...

   As for me I don't put my form in the oven...  I had a problem with a form warping on me...  I glue my bow at room temp for 5 hours or over night and then pop it into the oven for 5 hours...  Its called post curing...

   Just giving you more info to confuse you...  Lol...  
    After you do 7-8 bows you will start finding what works for you and will have developed your own methods...

[Major Boothroyd]

When I was cleaning up the form yesterday of excess epoxy, I turned away for just a moment to grab something, and this little guy suddenly appeared.  Maybe it's a good omen?

   

[monterey]

I know what I would name that bow.  

[Major Boothroyd]

That's exactly what I've been thinking!  I had another name picked out, but sometimes the universe speaks to you, and has a different direction in mind.

 

Originally posted by monterey:
I know what I would name that bow.      

[Mad Max]

I guess I should have told you to inflate the hose to keep the glass on the form when you did the hotbox run.

also, Inflate your hose to 65# or so and put each end in a bucket of water to check for air leaks.

[Major Boothroyd]

No worries, it was obvious to me... after I made the mistake, of course!  It's epoxied now.

I did test the hose ends in water, and also left it inflated for a couple of days just to make sure there wasn't any loss in pressure that would indicate a very slow leak.  Everything seems to be good to go.  I think today is the day to glue up.  I'll post an update later.

 

Originally posted by Mad Max:
I guess I should have told you to inflate the hose to keep the glass on the form when you did the hotbox run.

also, Inflate your hose to 65# or so and put each end in a bucket of water to check for air leaks.

Good Luck...

[Major Boothroyd]

The glue up went pretty well.  A friend assisted me, and another friend took a few photos of the process, but I haven't received those photos just yet.

After several dry fit tests, and some additional sanding, I was happy with the fit, and we epoxied it up, and clamped it in the form with the firehose inflated to 70 psi.

I put it in the heat box for 6 hours at an average temperature of 160 degrees.  After 10 hours I shut the heat box off, and let it cool for another 6 hours (overnight).  This morning I pulled it off the form, and then had leave to shoot a pair of tournaments with my longbow (300 and a hunter round).  I shot a personal best in both, so I must have been fired up by having glued up my bow!

Here it is off the form... there was a lot of excess glue that squeezed out.  In retrospect, I guess I used far more than enough, but I figured better to use a little too much than not enough.

     

After coming back from the range, I decided to cut off and sand off the excess epoxy.  That stuff is tough!  I ended up burning out a Dremel tool while trying to use a cut off bit.  I didn't have the patience to wait until I could get into my buddy's shop, since he's busy for the next few days, so I just sanded the rest of it off.

       

I'm pretty pleased with how the Eucalyptus burl looks.  I think it will look even nicer after it's sanded and a finish is applied.

       

It's pretty close to the bow I patterned it after, although with slightly thinner lams to try to come in at a lower draw weight.  The space in the epoxy towards the dark lamination strip close to the belly is because that piece of wood is exactly 1.5" wide, which is my target width for that part of the riser, and right now the rest of the riser and lams in that section are slightly wider than 1.5"

       

[Major Boothroyd]

Just a brief note to say that I am out of town for the next two weeks,  so I will not be able to work on the bow until after I return home, unfortunately.

[Skyhigh315]

Wow

First off, FANTASTIC work/progress on your project!  Second, and you probably won't believe this, but this 'mantis' thing is spooky.  Here's why:

My 11-year-old son and I have recently gotten into archery and have dived in with both feet.  We went from the $30 fiberglass kid's bow with the cedar arrows to high-end compounds to getting a 'first-time bowyer's kit' from Bingham in less than 3 months.  We started working on our oven a month ago and finished it in a couple of days.  What a blast.  Once we started on the press, we got a visit from.... wait for it....  a praying mantis.  He just flew in from out of the blue (and I've never before seen this particular type of insect in this area) and landed on my press.  I tried to shoo him away, but he was having none of that.  I false-swatted at him--he just stared at me.  I blew on him--he just ignored me.  I tried to push him away with a stick--he turned and faced me and then threw his wings up in a threat like that little spitting dinosaur in Jurassic Park.  So... we just waited for him to move on, which took almost an hour.

So... imagine my shock when I read your thread!  My two comments are THANK YOU for the encouragement, enlightenment and entertainment AND.... you CANNOT name your bow after the Mantis because WE are!

Keep up the great work.

[Skyhigh315]

Wow

First off, FANTASTIC work/progress on your project!  Second, and you probably won't believe this, but this 'mantis' thing is spooky.  Here's why:

My 11-year-old son and I have recently gotten into archery and have dived in with both feet.  We went from the $30 fiberglass kid's bow with the cedar arrows to high-end compounds to getting a 'first-time bowyer's kit' from Bingham in less than 3 months.  We started working on our oven a month ago and finished it in a couple of days.  What a blast.  Once we started on the press, we got a visit from.... wait for it....  a praying mantis.  He just flew in from out of the blue (and I've never before seen this particular type of insect in this area) and landed on my press.  I tried to shoo him away, but he was having none of that.  I false-swatted at him--he just stared at me.  I blew on him--he just ignored me.  I tried to push him away with a stick--he turned and faced me and then threw his wings up in a threat like that little spitting dinosaur in Jurassic Park.  So... we just waited for him to move on, which took almost an hour.

So... imagine my shock when I read your thread!  My two comments are THANK YOU for the encouragement, enlightenment and entertainment AND.... you CANNOT name your bow after the Mantis because WE are!

Keep up the great work.

[breazyears]

I named my last bow form design mantis lol.

[Major Boothroyd]

Well it sounds like there will be several different "Mantises" out there, then!

Skyhigh315, that's a cool story, and you and your son seem to be on the fast track in archery.  I wish I had started in earnest when I was 11.  On the other hand, it's never to late to continue to learn and improve.  I just got word today that a good friend and archery mentor of mine has just been accepted to the Resident Athlete program at the Chula Vista Olympic Training Center for Archery.  He has hopes of making the 2020 team to go for the Gold in Tokyo.  He started as a trad shooter in his late 20's.

As for my bow, I don't have anything new to report just yet.  I was away for a couple of weeks, and now I am heading out for a few days of bowhunting.

I hope to be able to get into my buddy's shop to use his bandsaw soon... like maybe this Saturday, and I'll also have to start thinking about building a tillering tree before long.  I'm not sure yet which type I will end up making.

[Major Boothroyd]

Okay, so just a quick post with an update.  I haven't been able to get into my buddy's shop due to his hectic schedule, as he just started a new gig, and he's been slammed.  

A friend of mine gave me a tip about a local "community woodshop," or "cooperative," that I looked into, and it looks great.  I signed up for the safety orientation tomorrow night, and after that I can become a member and get back to work on my bow.  What's been holding me up, specifically, is access to a bandsaw for the next operations I need to perform on my bow.  So... I should have some some progress to report very soon, hopefully.

I guess living in a city like Los Angeles does have some advantages to offset the downsides.  Here's a link to the Community Woodshop:

    http://www.communitywoodshopla.com

[breazyears]

You will certainly need to bring your own bandsaw blade if your cutting the limbs. The fiberglass will destroy a blade in a hurry. Cant wait to see yor bow complete.

LOL...  2nd that...

[Major Boothroyd]

breazyears, yes, I purchased one to fit my buddy's band saw (a Laguna 14SUV) about a month ago, in preparation.  I am hoping this facility has a 14" bandsaw that it will fit!

It wasn't an expensive blade, but still.  Who knows, perhaps I can return or exchange it, if it turns out not to fit.  I don't think I saved the receipt, however.

[Major Boothroyd]

Okay, I'm finally moving forward again.  So I joined the local Community Woodshop, and it's pretty great.  I took the safety orientation class last night, then went in today for a couple of hours to work on my bow.  Fortunately, they had a Laguna 14 SUV bandsaw, which is exactly what my buddy has in his shop, and therefore the bandsaw blade I purchased works perfectly on it.

One of the guys that runs the shop showed me how to properly swap out the bandsaw blade, and how to tension and adjust the guides, etc.

15 minutes later I completed my profile cuts on the limbs, and I re-swapped the blades.

I spent a little time on a belt sander to smooth out the cuts and to remove a little material to get very close to my final profile lines I drew on the blue tape on my bow.  The last bit of sanding I intend to do by hand.

I checked the bow's centerline with a piece of hi visibility BCYX bow string material, and all looks to be straight, centered and true with the bow.

I ordered some more smooth on epoxy, because I need to attach some limb tip reinforcements, as well as some accent pieces to the riser.

I have a couple of questions about that step:

My first question is about the riser section.  I'm intending to use a thin strip of Micarta (phenolic) and then a strip of hardwood on top of that, similar to the bow in the photos below next to my work in progress.  The third photo shows the riser section accent pieces fairly well.  Should I cut the hardwood strip in a radius profile, or do you think it will be okay to just bend and clamp a straight strip to the riser when gluing?  My only concern with doing that, is whether there will be chance that it will start to separate or delaminate eventually.  The radius is relatively mild, but I just wondered what most people do in this kind of scenario.

The 2nd question I have is whether or not I should put the tips and the riser near a lightbulb with some aluminum foil to help heat up just the areas near those pieces for curing, or whether I should just do a room temperature cure for those pieces?

The 3rd and final (for now) question is what grit sand paper do you guys recommend to use for roughing up the mating surfaces for the reinforcement pieces prior to epoxying?

   

   
 
   

   

The eucalyptus burl looks pretty cool, even before finish sanding and applying a finish to the bow:

   

[Trux Turning]

You can glue those overlays on the riser with no worries of them popping off. On the tips and overlays I'd just let them cure at room temps and use 80 or 100 grit to rough up the glue surfaces. That's a good looking bow you have going!

[bigbob2]

as Trux says, no worries with overlays, I make mine about .050 thick which facilitates the bending quite well, but i use 80 grit on the limb  on mine to prepare. No reason, just feel safer I guess.