If you rotate the pipe 180 degrees each cut, you'll already have the angle on one end of the segment due to the previous cut; then you make the same angle cut again (remember, the pipe is flipped), and you end up with the wedge-shaped segment.
If you rotate the pipe 180-22.5 = 157.5° (BTW, on Windows boxes that's done by holding ALT and pressing 2, 4, 8 in succession on the keypad; when ALT is released it prints the character) instead of the full 180°, you should get the necessary rotation, so you can fit the segments flush, rather than rotating after the cut.
And again, the lines I suggested be drawn lengthwise along the pipe are for easy alignment when cutting and assembling. Faustian(?) posted the starburst-circle which is correct to my description, one line every 22.5°.
Tim
If you rotate the pipe 180-22.5 = 157.5° (BTW, on Windows boxes that's done by holding ALT and pressing 2, 4, 8 in succession on the keypad; when ALT is released it prints the character) instead of the full 180°, you should get the necessary rotation, so you can fit the segments flush, rather than rotating after the cut.
And again, the lines I suggested be drawn lengthwise along the pipe are for easy alignment when cutting and assembling. Faustian(?) posted the starburst-circle which is correct to my description, one line every 22.5°.
Tim
actually it will require a good deal less than your calcs.
---------------------------
\ / \ / \ / etc.
---------------------------
make sense?
7.5 + 1.5 + 7.5 + 1.5 etc etc
i'm too lazy to actually figure it out.
...and it's true, you'll have to add, say, 1/8" for every cut, due to the saw blade thickness.
****edit
simultaneous posts!
I thought it was an 11.25°°°(yes, I can do it!) rotation.
How about this? How about I drink several Boddington's, then start sawing? I'll post back in a few hours...
Just kidding.
I devised a way to do the rotation. I will wrap a string around the circumference of the pipe, then divide the string equally into 16ths. That would be my guide for the slide.
Rhyme.
Dave
How about this? How about I drink several Boddington's, then start sawing? I'll post back in a few hours...
Just kidding.
I devised a way to do the rotation. I will wrap a string around the circumference of the pipe, then divide the string equally into 16ths. That would be my guide for the slide.
Rhyme.
Dave
Suggestion for cutting angle at 11°:
Clamp pipe fairly steady on the surface so it doesn't move.
Take square-can be anything that you know is square, a book, anything-and mark where the pipe is the largest . That is the diameter. Do that for both ends of the pipe. Mark on top and bottom of pipe for both sides. These will be your "center marks".
Take tape measure and measure outside circumferance exactly.
Multiply outside circumferance by 11/360. So if the outside circumferance of 6" diameter pipe is 18.85 inches, then 11° = 18.85 X (11/360) = .576. Or round it off to 9/16, (.562). Or 19/32, (.593).
You didn't really want me to go into 64ths, did you?
On the side you plan to cut second, measure that amount and put a mark to the left of the center mark. This will be your "angle mark". If possible, make your "angle mark" a different color, or mark it "angle".
After the first cut is made, go to the second side you plan to cut and rotate the pipe until your "angle mark" is straight up and down, just like your "center mark" was. Then cut.
That should give you 11° on the schnozz. Methinks we can skip the .25° angle part-beyond our capabilities.
PS: If multiplying angles just isn't your thing, especially after a few Boddingtons, then tell me either the precise outside diameter or the exact circumferance and my handy $15 scientific calculator and I will give you the answer forthwith.
Clamp pipe fairly steady on the surface so it doesn't move.
Take square-can be anything that you know is square, a book, anything-and mark where the pipe is the largest . That is the diameter. Do that for both ends of the pipe. Mark on top and bottom of pipe for both sides. These will be your "center marks".
Take tape measure and measure outside circumferance exactly.
Multiply outside circumferance by 11/360. So if the outside circumferance of 6" diameter pipe is 18.85 inches, then 11° = 18.85 X (11/360) = .576. Or round it off to 9/16, (.562). Or 19/32, (.593).
You didn't really want me to go into 64ths, did you?
On the side you plan to cut second, measure that amount and put a mark to the left of the center mark. This will be your "angle mark". If possible, make your "angle mark" a different color, or mark it "angle".
After the first cut is made, go to the second side you plan to cut and rotate the pipe until your "angle mark" is straight up and down, just like your "center mark" was. Then cut.
That should give you 11° on the schnozz. Methinks we can skip the .25° angle part-beyond our capabilities.
PS: If multiplying angles just isn't your thing, especially after a few Boddingtons, then tell me either the precise outside diameter or the exact circumferance and my handy $15 scientific calculator and I will give you the answer forthwith.
yeah, 11.25° (°°° woohoo) is the rotation.
unfortunately the starburst circle i posted only goes to 22.5°. DUUOY...
divide your string:
4 marks = 90°
8 marks = 45°
16 marks = 22.5°
32 marks = 11.25°
so, 32 equal spaces.
or you could do it kelticwizard's way, if you're into that sort of thing.
/andrew - likes to measure twice and cut once
unfortunately the starburst circle i posted only goes to 22.5°. DUUOY...
divide your string:
4 marks = 90°
8 marks = 45°
16 marks = 22.5°
32 marks = 11.25°
so, 32 equal spaces.
or you could do it kelticwizard's way, if you're into that sort of thing.
/andrew - likes to measure twice and cut once
My wife: "Why do all these people care?!?"
Me: "Because it's fun"
I have some toilet paper tubing at 1 and 5/8" diameter. Give me the numbers for it, and I'll test it real quick. Is it 11° per cut or per segment?
I'm inclined to go with Kelticwizard in concept, but Faustian did the modelling...
You know, once we solve all these problems, future projects on this level will have a clear formula. I plan to write all this in.
Dave
Me: "Because it's fun"
I have some toilet paper tubing at 1 and 5/8" diameter. Give me the numbers for it, and I'll test it real quick. Is it 11° per cut or per segment?
I'm inclined to go with Kelticwizard in concept, but Faustian did the modelling...
You know, once we solve all these problems, future projects on this level will have a clear formula. I plan to write all this in.
Dave
wait, upon looking back a few posts, I think we're all talking past each other on the angle thing.
I plan to cut once, measure the length, then turn the pipe 11°, sliding the length measurements with the turn, as pictured in my crude drawing above.
That turns into a 22° angle.
Don't confuse me y'all.
Dave
I plan to cut once, measure the length, then turn the pipe 11°, sliding the length measurements with the turn, as pictured in my crude drawing above.
That turns into a 22° angle.
Don't confuse me y'all.
Dave
LOL, I could mention some things women care about that men find mystifying, but these are waters best left unstirred.
You are not cutting this into 7.25" sections first, then cutting at 22.5°? You are cutting a long piece at 22.5°?
I suggest then, that you mark a circle-or put a rubber band, if you can find one long enough-around the pipe at a perpendicular angle. Then you can measure from the end you are cutting, instead of from the end you just cut.
You are not cutting this into 7.25" sections first, then cutting at 22.5°? You are cutting a long piece at 22.5°?
I suggest then, that you mark a circle-or put a rubber band, if you can find one long enough-around the pipe at a perpendicular angle. Then you can measure from the end you are cutting, instead of from the end you just cut.
you're not confused.
...but you didn't explain it right.
the rotated 11deg cut doesn't make anything turn into a 22deg angle. it allows the assembled wedge pieces to join up as a spiraling compound angle, which although it *could* be described as some kind of mathematical expression, we don't want to go there.
22deg has nothing to do with the rotation of the piece. 22.5deg is the actual *angle of the cut*, on both ends of the piece.
it just so happens that the rotation of the piece before the second cut, is 11 or 11.25. it could be anything sufficient to allow the returning spiral to clear the lower pipe, but i thought 11.25 would allow ease of construction, what with the 32 equal divisions of a circle and all.
but then y'all get all mathy with your fancy calculators, so nevermind.
just kidding
/andrew - likes geometry AND math
...but you didn't explain it right.
the rotated 11deg cut doesn't make anything turn into a 22deg angle. it allows the assembled wedge pieces to join up as a spiraling compound angle, which although it *could* be described as some kind of mathematical expression, we don't want to go there.
22deg has nothing to do with the rotation of the piece. 22.5deg is the actual *angle of the cut*, on both ends of the piece.
it just so happens that the rotation of the piece before the second cut, is 11 or 11.25. it could be anything sufficient to allow the returning spiral to clear the lower pipe, but i thought 11.25 would allow ease of construction, what with the 32 equal divisions of a circle and all.
but then y'all get all mathy with your fancy calculators, so nevermind.
just kidding
/andrew - likes geometry AND math
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