April 9th, 2012, 09:17 PM
Take-Down Long Bow
Alright I am going to start a new bow, well I already have. I have never done a build along before so if I forget to mention something or anyone has a question please let me know. I already have a oven and a limb press made, and am not going to go into detail about how to make them. If some one does need to know how they are made please let me know. I am starting with 1.5" W X 32" L pieces for the limbs, thickness will vary depending on desired draw weight. I am not sure the exact thicknesses that I am using for the limbs, I have had them sitting around for a while. I am using two pieces of glass, two parallels as veneers, two tapers, and a wedge. I have been using smooth-on from Binghams as an epoxy. Remember in this process that preparing is key, and that you can only cut once. Place masking tape over the "smooth" side of the glass, and mark the center line with a pencil down the entire piece, do this for all pieces of glass.
Now to make the limbs, remember prep! Start by getting out all your supplies, clean plastic wrap, the 2 part smooth-on, glue bowl, glue spredder, masking tape, finishing paste, oven (with working light bulbs, and thermostat), and limb jig.
Place your wood in the oven to heat up, this will help the wood and glue in the cureing process (10-15 min).
I will write more later with pictures, wife needs the computer. Please let me know if there is any interest.
April 10th, 2012, 08:14 PM
Ok today I glued up the limbs, there are a number of different ways that you can do this depending on the desired effect and cost. For this bow my "limb sandwich" was glass, parallel, taper with thick end to the butt of the limb, wedge flat side down, second parallel skinny side toward the butt, second parallel, and second piece of glass.
While your materials are in the oven warming you can mix your epoxy together, its very simple mix about 1/4 cup of part 1A with about 1/4 cup 1B. It doesn't have to be exact. Pull your wood out, at this point stop and make sure that you have everything that you need, make sure the wood is in the right order you want to glue it up in, masking take is covering the smooth side of the glass and a center line is drawn on the masking tape. Make sure that you have plastic wrap, and that finishing paste has been applied to all surfaces of the limb jig and components. Also make sure all the pieces are cut to a rough length of 32".
Now we are ready to start gluing stat with the piece of glass that will be the bottom and apply your glue evenly across the surface. Take your next piece which in my case was a parallel and apply glue to one side, this side will be what is seen when your bow is finished. Place it on the glass and then apply glue to the other side. Repeat this process all the way through the limb. Remember that the wedge goes flat side down.
1) Glass (string side)
3) Taper (with thick end toward the butt)
4) Wedge (flat side down)
5) Taper (thin end toward the butt)
6) Parallel (target side)
April 10th, 2012, 08:30 PM
Once you have a flat "limb sandwich", wash your hands this will make it easier to lay out the plastic wrap. Place a layer of plastic wrap over your limb jig, then place your limb sandwich on your jig. Add another layer of plastic wrap over the limb. Now secure the limb to the lower portion of the press, I just used masking take because thats what I had. I start with the lowest part of the limb and work toward the butt end. Make sure that the butt end of the limb stays aligned. The alignment of the butt end of the limb is what always gives me trouble.
Once the limb is secured to the lower portion of the limb jig place a 22 gauge metal pressure strip on top as well as the air hose.
Now secure the top portion of the limb jig to the bottom. Make sure that it is nice and tight.
Make sure that the air hose as well as the limb and pressure strip are still all centered. Then fill the air hose with 60 lbs. of pressure. I use a bike pump.
Place into your oven and allow glue to harden follow instructions. Smooth on is a min. of 4 hours I usually do about 4.5 hours.
After 4.5 hours has elapsed turn off oven and allow limb and oven to cool. After it is cool you can remove it from the press and take off all the tape and plastic wrap.
April 10th, 2012, 08:31 PM
PS my heating box needs to get new tin inside I know...
April 22nd, 2012, 08:09 AM
Bare with me the last week has been very busy, and today when I can work on it the weather doesn't agree. I will have more to come.
April 23rd, 2012, 09:09 AM
I like it! Just a thought though, I added some insulation to the inside of my bows and though I lost an inch over all, it retains and cooks a lot better now (and with lower watt bulbs).
Again though, I like it!
April 23rd, 2012, 08:06 PM
Ya I have used insulation foam on all the edges so that it helps hold the heat in, and I have a thermostat so that the temp is regulated pretty good. As I said earlier bare with me the weather is very crappy here and work has had me swamped. I hope to work on it some more on Wednesday as long as I get get home early enough the night before... have a night jump...
May 2nd, 2012, 02:58 AM
May 5th, 2012, 05:33 PM
Brilliant .... thanks for taking the time and trouble ... it's very much appreciated
May 20th, 2012, 05:17 PM
Once your both limbs are made remove all the plastic wrap and masking tape. Your limbs should have lots of dried resin on the sides. Now clean up the side by sand the sides so there is no extra dried resin, be careful not to sand to much off. IMG_3011.jpg
May 20th, 2012, 05:29 PM
Now that your limb is a little cleaner looking trace the your limb design onto the target side of the limbs, this is the side with the curve. Use the center line on the masking tape to make sure that your template is also center.
Next I like to cut out my limbs to rough shape, again make sure not to remove to much material. Remember rough shape we will do more sanding later to make it smoother and make sure there are no limb twists.
May 20th, 2012, 05:54 PM
At this point we will look at the riser bock. Your riser block should be the same width as you limbs. For my riser it is 17" long, 2 1/2" high, and 1 1/2" wide. I don't have pictures of how I cut the block. Make sure that you cut the correct fade outs angles into your riser. Once your fade outs are cut you can drill your your limb bolt hole and guide pin hole. I use a jig from bingham projects to make sure that my distances are correct for both my riser and limbs. The guide pin hole should be a drilled with a 1/4" bit, 1/4" deep. The bolt hole should be drilled with a 27/64" bit, 1-1/4" deep. Once that hole is drilled tap in threads into the 27/64" hole using a 1/2" tap. Then glue in the pin and screw in the metal threading bolts to lock down the limbs.
May 20th, 2012, 06:01 PM
Now look back at your limbs, trim off 1/4" from each end making them square. Place your drill jig on the string side of your limb, and align it with the bottom of the limb. Once you have the limb and jig aligned and on the butt end drill a 5/16" hole through the limb make sure to use the correct hole. Then drill the guide pin hole 1/4" deep (MAKE SURE YOU ARE DRILLING ON THE STRING SIDE). Once both limbs are drilled attach them to the riser block.
May 20th, 2012, 06:21 PM
Cut in your string groves, you should already have area that needs to be filled out marked from when you traced out you limbs. Take a round rasp and file out this area, make sure not to go to deep.
Now you can string up your bow, check your bace height measure from the string side to the string it should be between 9"-10". The stronger limb which will have the shortest distance from the string side of the limb to the string will be the bottom limb. Both limbs should be within 1/4" of each other, if they aren't take off the masking tap from the bottom limb and use 120 wet or dry sand paper to sand both the string and target sides of bow until the limbs are within 1/4". Now make a 18" tillering stick and tiller your bow. Place the tillering stick between the riser block and the string, this will allow you to see all apparent limb twists.
If there are limb twists twist the limb in the opposite direction and see if this corrects the problem. If this doesn't fix the problem then you will need to remove material from the sides of the limb. Please look at more detailed information on tillering if you have further issues, or ask me a specific question. This issue can be very hard to describe typing and can be specific.