Interpretation Of An Italian Renaissance Bow
Posted: Thu Jul 26, 2007 1:43 pm
It was by coincidence that an earlier posting by Grahame A had resurfaced a couple of weeks ago regarding this style of bow. I was becoming bored with producing fibre glass back and bellied bows and wanted to get back to using bamboo. The style of bow described by Grahame A was in fact going to be my next project. If you don't have a go you will never know!
I had a small illustration of a strung bow in this style recreated by Hillary Greenland as a basis for this project. As you would appreciate it is not always an easy task to take a five inch illustration to a seventy inch drawing and then interpret how the bow would look when unstrung. Having had some previous experience with making bamboo laminated slightly recurved bows I was in with half a chance. Although the bow may come off the form true the form profile, during tillering the recurved tips will pull out / take a set. With a bit of experience you learn how much extra recurve to put into the form to compensate. It is a bit of a grey area but I think the recurve tips take a set and then hold whilst the overall limb takes set and or some string follow.
I decided to attach some photos of the finished bow and not do a build along as the construction techniques are similar to my previous postings on bamboo laminated bows and the only thing that changes is the bow form.
With the excess glue sanded off and the limb widths and thickness trued up it was time to go to the tiller board. The bow was virtually in tiller although there were some stiff spots, almost mirror image one limb to the other. I had expected this as I was down to the dregs of my bamboo stock (some unfriendly nodes). It is for this reason I always use 'twins' when making bamboo bows.
The moment of truth had arrived, being satisfied with the initial tiller it was now time to put on the correct length string to get a true appreciation of the bows tiller. Tillering strings give you a guide to tiller, but not necessarily the correct answer, more so with bamboo bows as opposed to glass bows. You will notice a slight difference (photo 02) in the curve just out from the handle right to left. The tiller held true until after about twenty arrows. What was to be the lower limb may now become the upper limb, as I have found from experience it can take over a hundred arrows or more for the limbs to settle in. This is one advantage with having equal length limb bows as you can up end them if needed if you haven't cut in a shelf or finalised the handle shape. At present the handle shape dictates that arrows are shot off the knuckle. Once the tiller has settled I will do the final shaping of the grip area.
I am extremely happy with the end result as the weight comes in at about three inches into the draw and progressively builds up through the draw and that the string lays true to the centre of the handle. Achieving the graceful flowing lines of this classic style of bow was easier than I had first anticipated. Obtaining the correct profile in the back set handle and limb thickness would determine the degree of curve in the limb from handle to mid limb which would then flow into the gently recurved tips.
The handle section was laminated from a piece of 3x2 hardwood off-cut lying around the workshop floor with a strip of rock maple for a highlight. Tip overlays were of a similar construction. The core is made up of five laminations of spotted gum to a total thickness of 7 mm and Moso bamboo was used for the back and belly.
After some shooting in on the weekend the upper limb took a set that threw the bow out of tiller. Because of the nature of these bows I will shoot a lot more arrows before I start altering the tiller. The arrows (560 grain, footed) go where you point them and there is no hand shock although the bow is out of tiller. Once shooting in the bow I anticipate that it will settle in around the 50# mark.
Unstrung bow is 66" n to n in a straight line and takes a 64" string. The fast flite Flemish string for this bow was made by Steve Wallace.
(Will be off the net for 7 to10 days, stuff up by major Telco)
Daryl.
I had a small illustration of a strung bow in this style recreated by Hillary Greenland as a basis for this project. As you would appreciate it is not always an easy task to take a five inch illustration to a seventy inch drawing and then interpret how the bow would look when unstrung. Having had some previous experience with making bamboo laminated slightly recurved bows I was in with half a chance. Although the bow may come off the form true the form profile, during tillering the recurved tips will pull out / take a set. With a bit of experience you learn how much extra recurve to put into the form to compensate. It is a bit of a grey area but I think the recurve tips take a set and then hold whilst the overall limb takes set and or some string follow.
I decided to attach some photos of the finished bow and not do a build along as the construction techniques are similar to my previous postings on bamboo laminated bows and the only thing that changes is the bow form.
With the excess glue sanded off and the limb widths and thickness trued up it was time to go to the tiller board. The bow was virtually in tiller although there were some stiff spots, almost mirror image one limb to the other. I had expected this as I was down to the dregs of my bamboo stock (some unfriendly nodes). It is for this reason I always use 'twins' when making bamboo bows.
The moment of truth had arrived, being satisfied with the initial tiller it was now time to put on the correct length string to get a true appreciation of the bows tiller. Tillering strings give you a guide to tiller, but not necessarily the correct answer, more so with bamboo bows as opposed to glass bows. You will notice a slight difference (photo 02) in the curve just out from the handle right to left. The tiller held true until after about twenty arrows. What was to be the lower limb may now become the upper limb, as I have found from experience it can take over a hundred arrows or more for the limbs to settle in. This is one advantage with having equal length limb bows as you can up end them if needed if you haven't cut in a shelf or finalised the handle shape. At present the handle shape dictates that arrows are shot off the knuckle. Once the tiller has settled I will do the final shaping of the grip area.
I am extremely happy with the end result as the weight comes in at about three inches into the draw and progressively builds up through the draw and that the string lays true to the centre of the handle. Achieving the graceful flowing lines of this classic style of bow was easier than I had first anticipated. Obtaining the correct profile in the back set handle and limb thickness would determine the degree of curve in the limb from handle to mid limb which would then flow into the gently recurved tips.
The handle section was laminated from a piece of 3x2 hardwood off-cut lying around the workshop floor with a strip of rock maple for a highlight. Tip overlays were of a similar construction. The core is made up of five laminations of spotted gum to a total thickness of 7 mm and Moso bamboo was used for the back and belly.
After some shooting in on the weekend the upper limb took a set that threw the bow out of tiller. Because of the nature of these bows I will shoot a lot more arrows before I start altering the tiller. The arrows (560 grain, footed) go where you point them and there is no hand shock although the bow is out of tiller. Once shooting in the bow I anticipate that it will settle in around the 50# mark.
Unstrung bow is 66" n to n in a straight line and takes a 64" string. The fast flite Flemish string for this bow was made by Steve Wallace.
(Will be off the net for 7 to10 days, stuff up by major Telco)
Daryl.