I insulated the inside of the oven box to deal with heat retention issues. I bought a roll of insulation that is made from a double layer of bubble wrap with heavy duty foil on both faces. It is just under a 1/4 inch thick and lightweight.
I used a staple gun to attach it to the inside walls of the box and to the under side of the box cover.
I then added two additional light bulb bases to the boards that I had made up earlier. I used 100 watt bulbs in the center two bases so now I have (4) 150 watt bulbs and (2) 100 watt bulbs.
After one hours, the temp had risen to my goal temp of 160F. I felt the outside of the box in several locations and could not feel any heat escaping through the walls or lid.
After 2 hours, the temp had risen above my goal but I consider this a good thing since I will now be able to crack the lid a bit or perhaps unscrew one bulb to control the temp.
The oven box is finished and ready for the big day.
I did a dry run and found something I never thought through (Which is the point of a dry run)
While the riser fits great on the empty form, adding the strip of fiberglass backing, four tapered laminations and the fiberglass face caused the fade-outs to lit poorly. I did not factor in the tapering of the laminations as they work away from the center of the riser. I discovered a gap at the fade-out area. I felt this gap was larger than it should be and do not want a large amount of epoxy at this hinge point. I might just be over cautious but I want a better fit and a consistent glue line. The dark black area near the thinest part of the riser is what I am worried about.
I sanded down the riser until it fit better.
I also made some tillering attachments that will slide on the end of the un-shaped limbs before I taper the sides and make the string groves. they are made from 4 large washers that I epoxied together and cut notches in
So, enough waiting already. Time to glue this bow up.
I laid out everything I needed since the dry run a few days ago. Then I put both quart containers of the epoxy in a basin of hot water to warm them up a bit.
Next, I cleaned all the wood and glass surfaces and laid them in the order in which I would glue them.
1. is .050 clear glass
2. is .020 kingwood vernier
3. is .090 thick hard maple taper (two pieces glued together to make one long piece)
4 and 5. is .065 thick hard maple taper (two pieces glued together to make one long piece)
6. is a piece of hard maple .060 parallel from the piece of wood my Dad cut. (two pieces glued together to make one long piece)
7. is .020 kingwood vernier
8. is .050 clear glass
Missing from the picture is the riser.
Fast forward to a completed glue up with the warmed epoxy. Due to the mess and the fact that I was working alone, I did not slip out of my sticky rubber gloves to take pictures along the way. What a slippery mess to work with. I used a combination of spring clamps and rubber inner tube strips to compress all the layers. I had more C-clamps at the center (on the riser) but I took them off once I realized that they stuck up higher than the sides of the box and the cover would not lay flat. So much for a complete dry run. I should have tried the lid of the box also. Oh well. live and learn.
Here is a close up of all the layers and all the extra glue that oozed out. I also learned that I used too much glue. I think I could have built two bows with what came out from between the seams. Once again. Live and learn.
It took a solid hour to free the bow from the form. Removing the spring clamps was easy, The epoxy covered strips of inner tube proved to be a bit tougher. The form cleaned up easy because of all the tape I used to protect it.
The bow was a little tougher. The extra epoxy was everywhere and held bits of the inner tube captive.
To save on a mess in the shop (and because it was a nice day) I took the bow out to the back patio behind my shop. The breeze would blow all that nasty fiberglass dust away.
I learned that I need to place a layer of plastic wrap between the last layer of glass and the aluminum pressure strip. I didn't do that with this bow and needed to sand away the excess epoxy to free it from the bow. This also gave me my first look at the glue lines between the layers of wood.
after sanding both sides I could pry away the aluminum pressure strip.
Then I just had to peel away the tape to see how the Kingwood looked under the clear glass.
And the other limb.
and finally the back of the bow. Everything looked good.
Then I worked on the riser. there was a lot of epoxy to remove.
The risers looks good and so do the skive cuts that joined the strips of maple
I then made a line on each end of the limbs that was 34 niches from the center point of the bow. (68 inches overall length) I used a fine tooth hacksaw to cut the ends off.
Both ends measured the same thickness.
Then I used the washers to string the bow before I cut the string grooves.
Here is is strung but with a bow string that is too long so the brace height is only about 5 inches. I used the string from my longbow. It is the only string I have for that bow. (that is an important point that will be realized a bit later.
To check for limb twist, I wanted to look at more than just saw cuts at the ends of each limb so I took a carbon fiber shaft and taped it in place on each limb. I made sure they were at 90 degrees to the limb.
With the washers in the measured center of the limbs, there looks to be no twist in the limbs.
I marked the centerline of the bow along the entire length and used a strip of wood to mark a straight line for the limb taper toward the string nocks.
Just as I was marking the last line on the other limb, all hell broke loose, Something whacked me in the finger and the bow jumped up off the table. When I figured out what it was, I had to search high and low for both washers. The bow string (my only string for my bow) had broke. My guess is that I left too sharp an edge on the inside of the groove and it cut through the string. Now I have no string for either bow. Time to scramble and locate a 64 inch string for my bow and a 63 inch string for the new bow.