Miter angles and how to cut them

[Chadi]

Hi everyone. How are things. I'm new to the whole woodworking thing and need some advice on making miter cuts. As I've been learning with the miter table/gauge on my BT, if I set the angle of the SMT to 33 degrees I get a piece of wood (I'm cutting a 2x4) with a 57 degree angle (angle between the long edge of the wood and the angled cut). However what I want is a 33 degree angle on my piece of wood. So I would theoretically need to set the SMT to 57 Degrees which doesn't exist. I can get the 33 degree angle by sticking my triangle over the SMT fence (I use the additional 90 degrees from the triangle) and than my piece of wood against the triangle. There has got to be a better more accurate way to do this. Any suggestions?

Thank you,

Chadi

[LCHIEN]

Hi everyone. How are things. I'm new to the whole woodworking thing and need some advice on making miter cuts. As I've been learning with the miter table/gauge on my BT, if I set the angle of the SMT to 33 degrees I get a piece of wood (I'm cutting a 2x4) with a 57 degree angle (angle between the long edge of the wood and the angled cut). However what I want is a 33 degree angle on my piece of wood. So I would theoretically need to set the SMT to 57 Degrees which doesn't exist. I can get the 33 degree angle by sticking my triangle over the SMT fence (I use the additional 90 degrees from the triangle) and than my piece of wood against the triangle. There has got to be a better more accurate way to do this. Any suggestions?

Thank you,

Chadi

well, you know its the difference between 33 degrees from the vertical and 33 degrees from the horizontal. When the SMT is square one is the diffference from 90 dgrees (e.g. 90-57=33). They're called complementary angles.
http://www.wtamu.edu/academic/anns/m...3_geom_ans.htm


Same thing for the bevels. You'll just have to know which one you want.

Its difficult to make the mechanisms work at more than 45 degrees since the complimentary angles are so acute.

the usual way to make the acute cuts is to use a jig. A Triangle of known angle like you did can work (I would not use a drafting triangle - too thin and not enough support).

My usual method is to take a large square, place the front side to the face of the miter fence,
place the wood to be cut along the right side and rotate the miter fence angle 33 degrees to the left (or sometimes right will work).
Adjust the position of the square block right or left to have the workpiece hit the blade where you want the cut to start.

Now the critical thing (for your safety) is to
1) fasten the square block to the miter fence
2) fasten the work piece to the square block - use some tape or a
an underlying sacrificial board and temporary screws or vertical fixture clamp
3) fasten a little foot or something to support the back end of the work
4) push the whole shebang with the miter fence knob, the clearances to the blade will be pretty small if using any boards, it might be better if cutting sheets.
5) visualize the whole cut thru and make sure you won't be cutting anything that you don't want to including fence, fixture, fingers, SMT etc.

[leehljp]

If you want a jig for making angles larger than 45°, here is a link to one that I made. You need to know and use the complementary angles as noted by Loring.

http://www.bt3central.com/showthread...hlight=Greater

[Chadi]

Thanks

Thanks for the input guys. I'm familiar with the angles just wanted to learn about some other techniques I may not be familiar with.