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[email protected] dagmargoodboat@yahoo.com is offline
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Default homemade flex couplers

On Nov 10, 11:09 am, "Steve W." wrote:
Ned Simmons wrote:
On Tue, 10 Nov 2009 06:24:49 -0800 (PST),
wrote:


On Nov 10, 9:10 am, Ned Simmons wrote:
On Mon, 9 Nov 2009 18:59:02 -0800 (PST),
wrote:


(view in Courier or other fixed font)
.--.
.
.--. \
. . |
/ \ / b.
| - |//|
|.--' '----'/ .
a. |'--. .----. /
| - |/
\ / /
/. .:
/ ' -- ' :
bore _
|=|
[___] --clamp screw
a = "hinge"
b = "cut"
I've made some homemade flex couplers using setscrews to bite the
shafts, but clamps are sooo much classier.
This crappy drawing is an end view of the clamp portion of a helical
flexible beam coupler. Question: how's that cut made, from b. to a.?
Slitting saw. If you were to look at a section thru the cut you'd see
a radius equal to that of the saw adjacent to "a" in your drawing.


--
Ned Simmons
Really? I just posted the opposite, that the cut's square-bottomed,
but now that you say it I'm not so sure.


Would the hinge be flexible enough with a big arc of metal left at the
bottom of that cut? I wouldn't think so, but if you're right it must
be.


I've got a Helical brand beam coupling and a Huco Oldham coupling in
front of me and both have a radiused bottom on the slit on the far
side of the bore.


Without that radius at the bottom you would have a real nasty stress
point at the corners of the slot.

--
Steve W.


Yep, both that and how thin the "hinge" was troubled me--it didn't
look strong enough.

I was thinking of forming the "pivot" area of the hinge (the part near
'a', the portion that bends as you tighten the clamp) by drilling,
thus forming a rounded, stress-relief area. Like this (crappy drawing
#2):


(view in Courier, or other fixed font)

/
/
/
/
| a. ___
| _ / \
| / \_____| |_____
| | _____ _____
| \_/ | |
| \___/
|
\
\
\
\ /
\_______________/


I still might do that.


Thanks a bunch to all,
James Arthur