First Lam Bow...49" Recurve...47 1/2" nock to nock

[Widowbender]

great thread!!  

David

[onemississipp]

Well I got the glue-up done yesterday, not happy with the results. There were a number of things that need to be changed. The belly/back of the riser for one thing needs redesigned. I got some gaps in the glue up that I did not get in the dry runs.


Lesson # 1

I thought about this one in the beginning. I used the airhose method, the air hose is 2 1/2". I was glueing up a 2" recurve, to get equal pressure I could really only have a 1/2" gap between top and bottom form. I had about 1".
I had gaps on the belly of the riser in the dips.

Fix for lesson # 1

Come up with a clamping system.


Lesson # 2

Reduce tight curves, on the back of the riser I made a hump thinking it would help in getting lams and glass to accept the dips, in the back/belly of the riser.
I had gaps on the belly of the riser in the dips.

Fix for lesson # 2

redesign belly of riser..


Lesson # 3

Even though you are laminating there will still be spring back of the material once the glue up is done. I'm talking about the curves once the bow was cured I removed pressure and the limb tips sprang back about a 1/4" off the form.

Fix for lesson # 3

Account for some spring back in the form design.
Exaggerate the ending of the curves.

Lesson # 4

Dry and wet runs are different.

Fix for Lesson # 4

Go with your gut...

When I think of more I'll add them, I'll add pics later also.

I thought about cutting it in half and making a couple of kids recurves, but I need to go ahead and cut it to profile and see if my calculations on the lam thickness got me to the draw I wanted.


Also I learned the bow that is pictured in the PDF file is not the bow that is described in the text.

That's not true, the bow is pictured twice, the first pic of it being drawn..and then again where the finish is being applied.

[onemississipp]

Total cost for a good education so far is about $77.50..


This thread may be running for a couple years till I get it right....sorry guys!

After some thought and looking, I think the riser needs to be about 12", and not 8 1/2" as the text stated.

[onemississipp]

After looking at it again tonight, it didn't come out as bad as I thought. I'll get some pics up tomorrow and explain.

[onemississipp]

I started to make a template to know how long to cut my glass and tapers. I used some clamps I pick up awhile back and think I will get some more and use these instead of an airhose. More on that later.

 

 

Then I needed to cut my glass and tapers to 50", my tapers where 36" plus a little to thick on the butt end. To get where I wanted to be .060, I cut 4" from the but ends.

 

[onemississipp]

Those are the Red Elm lams and some packing and other boards I was using while cutting. You can almost see the 4" marks.

   

Ever wonder how they will ship two 72" pieces of glass to you? I thought since I was paying extra for shipping it would come in a 72" flat box, I was wrong.

   

The finished bow will only be 1 3/4" wide but I'm glad I ordered the 2" glass. Once I got it out of the packaging, one piece had a hughe splinter pulling up from the edge and running about 1/8" toward the center of the glass. It was in a place that was not able to be cut off, but will be gone once the thinning from 2" to 1 3/4" begins.

Next I started doing my dry runs and checking everything out.


   

[onemississipp]

 

 2" blue painters tape on the back of the glass.

Oven heating up.


 

 

[onemississipp]

A note about doing a dry run, the dry run acts alot different than when the actual glue up begins. Once you have the glue on the lams and glass they enjoy sliding around, now throw some plastic wrap on that and you can't really see whats going on. Take your time I used Smooth-on and spent about a total of, guessing here, 20 to 25 mins getting everything glued and clamped in.

Time for the glue up, so I laid everything out.

 

 

I didn't get any pictures of the actual glue up, I was busy trying to hold everything together and my helper was getting tape and holding plastic wrap. When the actual glue-up started I found out quick I needed more hands it was a good thing I had my 3 year old daughter at home with me that day! To get the riser pressed down in the form and held in place I used strapping tape. I pressed it in by hand and things where slipping and sliding. My helper said "Dad you need a piece of tape?" I said "Yeah, cut me a piece about a foot long." it was then I reliezed  what I just said and needed more hands. I looked over and she was trying her best to get the end of the tape peeled back and she had the scissors at the ready. Once we got things worked out and the bow in the oven, we took a break and went swimming.

 

*The form does need 8 (4 per side) braces on it, I went with the 4 for now and added a rachet strap in the middle of the form before adding the air to the air hose. I went with 60psi in the hose. the other 4 braces should be places near the fades*

I cooked the bow for 6 hours at 150 degrees fahrenheit. Here is a pic of it after glue up.

[onemississipp]

*I'll get a picture up that will explain this a little better. The blue painters tape when pressed will become slightly darker than the unpressed tape. On the belly of the bow you can see where the air hose pressed. At the end of the curves where tthe gap is about 1/2" you can see that it pressed the full 2" width.

You can kinda see it in the below pic.

 

   

Note the gap!!! left side belly of riser..

   

This is the opposite side of the riser where the gap is. No gap.

   

I think the bow will be fine with the gap on the side, once the handle area is cut in. I'll get more pictures as I go.

[TNstickn]

Im feelin lucky for ya!!! Maybe the gap is shallow.

[joebuck]

Great attitude Dustin!  thats 99% of it as you already know from makin wood bows..if you are ever near Oxford, I would be glad to show you my humble bows and shop...maybe we could trade ideas.  Joey Buchanan

[onemississipp]

That would be great Joe!

Well it turns out I was right about the gap only being there on the side. I took it to the sander and the gap only runs about 1/8" toward center. So now I need to figure out my limb profile and get this thing rolling.

TNstickn thanks for the added luck!

[Cupcake]

Dustin,
It looks very nice so far.  The gap was purposely put there by a higher power to keep you on your toes.

The first bow is a great thrill and you will be hooked.  I now spend more time thinking about building the next bow than anything else, even motorcycles.
Kevin

[onemississipp]

Next thing to do is check the limbs for straightness and verify my center line. I use the weighted string to check my limbs and the center line I drew on the glass before I glued it up. Drawing the center line on the glass after I put the painters tape on before glue up, was a smart move I think.

 

 

Next is the limb layout,  The limb taper 1 3/4" to 7/8".

Lesson # 5

Using packing paper as a template, or any other thin paper is not a good idea. When bending the template into the curve it allows it to twist. I found this out after I had used it.

Fix for Lesson # 5

Use something like poster board.

 

[onemississipp]

Poster board in the picture.

Sand to the template.

 

This is part of the twist from the thin paper template. Alot of time could have been saved my using the poster board.

I used left over glass and lams for tip overlays.

 

 

After a little work and beginning tiller.

 

[onemississipp]

Tillering involed more than I thought it would. I was under the impression glue it up, cut it to profile and it's done. I was wrong, tiller didn't take long about an hour. I took the string off my supermag and strung up the turkey bow. The limbs were a bit twisted, I made sure my string nocks were even, this brought the string closer to center. The string was still off center, so looking at the bow from the belly the string would be off center to one side. To correct this I sanded the opposite side. Going slow and after sanding alittle I would pull the bow a little and check it again.  Here it is braced and pulled to about 27".

   

Picture makes it look a little strange, of course I'll get more up later.

   

I still need to shape the handle, tips and apply a finish

[onemississipp]

I haven't checked weight yet, but it feels about what I wanted. Close to 45# I'll get a scale on it later.

[onemississipp]

Bow is 49" end to end, 47 1/2" nock to nock.

[onemississipp]

Almost finished with the handle and tip shaping, here are some pictures.
 

 

 

 

[onemississipp]