On Mon, 15 Mar 2010 18:11:52 -0500, Wes wrote:
Louis Ohland wrote:
The significant question is how do you machine the passage for the block
so it's got somewhat square corners? Or is a slight radius OK? I see the
square broaches, but isn't an acutely square corner a good place for a
crack to start?
One approach would be to drill four holes at the corners of the block
passage, broach them square, then use a hole saw for gross metal
removal, followed by a 1/2" mill to square up the sides. Is there a less
manly-man way of doing it?
The drill the four corners, milling, some filing, and then figuring a way to lock the
spindle of your vertical mill so you can mount a sharpened piece of HSS to use your mill
as an ArmStrong vertical slotter comes to mind.
Wire EDM has issues. Ed Huntress has posted on this at various times. The jist of it is
if they go slow, maybe not so bad but if they rip through it, you are likely going to have
micro cracks. Now that I think of it, John, who runs a shop with big machines had some
splines cut and the subject going too fast came up iirc in RCM.
I'm curious as in a question to the group, would the slotting device Bridgeport made to
mount to the rear of the turret have the stroke to slot his receiver or more interesting
to me, a Winchester/Browning 1885 High Wall receiver?
I'm still kicking myself for not getting to North Carolina with my uncle in time to pick
up his free standing slotter he left in his basement when he divorced and moved away. Oh
well his son got 1100 bucks for it on Ebay and the money financed his securities license.
Son didn't think dad wanted it and after it turned out as it did, Dad felt good about his
son getting benefit out of it. Sure would have been nice though to have it in my shop. Oh
well, sometimes you win, sometimes you loose. Hard to feel bad on how that one turned
out.
Wes
Wes
=========
From the more modern work [after most single shot actions were
designed] on stress distribution, the corners contribute very
little to the strength. Therefore it would appear that within
reason a radius would be better as this avoids a stress riser
[inside corner] as well as being easier to machine.
see
http://www.eng-tips.com/viewthread.c...=156717&page=1
http://nptel.iitm.ac.in/courses/Webc...3_lesson-2.pdf
http://www.eng-tips.com/viewthread.cfm?qid=29690
http://www.mscsoftware.com/Solutions...px?storyid=131
http://www.scribd.com/doc/25185918/Lecture-19
for pictures see
https://kb.osu.edu/dspace/bitstream/...26_i02_008.pdf
http://www.scribd.com/doc/7827348/US...nery-Repairman
Sounds like a fun project. Let the group know what you decide.
Unka George (George McDuffee)
...............................
The past is a foreign country;
they do things differently there.
L. P. Hartley (1895-1972), British author.
The Go-Between, Prologue (1953).