Copper John 3rd Axis ?
03-27-2004, 02:13 PM
#2
Join Date: Feb 2003
Location:
Posts: 520
RE: Copper John 3rd Axis ?
You need the capacity to set either the bow or the sight in a vertical plane where they can be tipped forward or back without leaving the vertical plane. There are a number of gizmos designed to do it, but if you have an accurate level, you can just clamp or position the bow so it's vertical side to side in the various leaning forward or back positions.
You set the bow planer, with the string vertical, hopeful the sight level is level, if not you have to adjust this, and how exactly you do that is a wole other subject. You then lean the bow 30-45 degrees forward and planer (still vertical by whatever means you have established. If the bubble isn't level, you adjust third axis till it is. Do the same leaning leaning back, go back to string vertical. In every position the bubble should remain level.
The principle is that when a level is showing level in the vertical axis, it may show something different when leaned forward or back, of the vial is skewed in those positions.
Another option is to bolt the sight to a very flat piece of plywood (or whatever), and put that piece of wood in a vise so that the ply is dead vertical, then just move the ply forward and back in the vise to adjust 3rd axis. Then with the site perfected, put it on your bow. Do some checks to see if the sight when on the bow performs properly, if it does, you don't need to worry about jigging the whole bow.
Those little spirit level both in the sight and on the various devices we use to adjust third axis, are often very inaccurate. If you have a plumb bob, it will give you an accurate check of the plywood vertical, or string vertical.
On some one cam bows, the string isn't vertical when the riser is.
When you get it set, you might want to scribe an alignment mark across the joint so you know where it is set right on your bow. This is a useful check to verify that it hasn't been knocked out of alignment, and to reset it, or just as a guide if you ever move it to another bow.
You set the bow planer, with the string vertical, hopeful the sight level is level, if not you have to adjust this, and how exactly you do that is a wole other subject. You then lean the bow 30-45 degrees forward and planer (still vertical by whatever means you have established. If the bubble isn't level, you adjust third axis till it is. Do the same leaning leaning back, go back to string vertical. In every position the bubble should remain level.
The principle is that when a level is showing level in the vertical axis, it may show something different when leaned forward or back, of the vial is skewed in those positions.
Another option is to bolt the sight to a very flat piece of plywood (or whatever), and put that piece of wood in a vise so that the ply is dead vertical, then just move the ply forward and back in the vise to adjust 3rd axis. Then with the site perfected, put it on your bow. Do some checks to see if the sight when on the bow performs properly, if it does, you don't need to worry about jigging the whole bow.
Those little spirit level both in the sight and on the various devices we use to adjust third axis, are often very inaccurate. If you have a plumb bob, it will give you an accurate check of the plywood vertical, or string vertical.
On some one cam bows, the string isn't vertical when the riser is.
When you get it set, you might want to scribe an alignment mark across the joint so you know where it is set right on your bow. This is a useful check to verify that it hasn't been knocked out of alignment, and to reset it, or just as a guide if you ever move it to another bow.
03-27-2004, 07:19 PM
#3
Typical Buck
Join Date: Dec 2003
Location: Mertztown, PA
Posts: 970
RE: Copper John 3rd Axis ?
This is a more crude and unexacting method I've heard of and used. It seems to work in that my arrows don't linger on sloped shots.
Tie a plumb bob or something weighted from your ceiling with a string that runs to the floor. This will represent true vertical. Now kneel on the floor in front of the string with your bow and draw as you would (with an arrow of course - don't want to dry fire it!) Aim so that the top pin is on the string and level the bow using the sight level. The pins below the top pin should follow the string as closely as possible. If not, adjust the 3rd axis accordingly.
Hope it helps......Fritz
Tie a plumb bob or something weighted from your ceiling with a string that runs to the floor. This will represent true vertical. Now kneel on the floor in front of the string with your bow and draw as you would (with an arrow of course - don't want to dry fire it!) Aim so that the top pin is on the string and level the bow using the sight level. The pins below the top pin should follow the string as closely as possible. If not, adjust the 3rd axis accordingly.
Hope it helps......Fritz
