Re: Chinese Whispers - Was Angle Iron Ways

Hi All

amazing how a simple question on how to "grind" a stupid piece of
angle iron turns into a debate on "something completely different" :-)))

OK, to comment on some of the answers to my "quest" ...

1 Fred's solution of rotating 45 deg to use the built-in 90 deg angle
falls out of my brief - whatever that brief might have been :-)).
This is essentially cheating :-))) To be truthfull, what I want is
the angle iron vertical - and I WANT a 90 deg V formed on the edge !
Thank you Fred for the "penultimate" solution - perhaps I should
offer a reward here :-))

2 OK on Dave's "how to make a flat surface" routine - interesting
stuff (once I found the eventual link :-)))))) This is at least VERY
useful.
At 50 bucks/pounds/shekels/pence an hour, I would not want to pay
someone to true my ways using this method however :-))

3 On Graham's esoteric solution - I use the term esoteric in a non-
demeaningfull way Graham :-))))))) I SERIOUSLY looked at this solution.
And it is a nice solution (perhaps I shouldn't start a sentence with
"and" BTW - my one-armed English teacher would have hit me with a
leather
strap - another story maybe :-) My ONLY problem with this is time -
has ANYONE considered how long it takes to remove 3mm^2 of mild(ish)
steel via this option ???? (the width of the angle is 3mm - roughly
1/8" for the 5% of the the world that doesn't use the metric
system :-)))))) My calculations are VERY ROUGH, but at 10A/m^2 it
would take something like 50-odd hours to remove ONE 45 deg side of a
1m length. It's not personal Graham - I LIKE watching paint dry :-)))
I DO like this solution and have even taken to playing with
Vectorworks on my Mac (:-) looking for something that could reduce
the overall time required to
do this. I considered a continuous flush system rather than a bath -
whacking up the current would of course improve the removal rate but
as I recollect from previous attempts at producing "the Queen's head"
from a coin on a plate from a prior test (about 30 years ago
admittedly :-), it ends up looking like a dose of the pox :--))

4 Stuart's box section also falls out of the brief - see 1 :-) Thank
you for your solution Stuart.

All I want is to make an accurate 90 deg V on a 50mm angle iron -
nothing more, nothing less - there just has to be a way (pun
intended :-))

On a point, I spent a fabulous 2 week holiday in Egypt some years ago
- while walking through a "bazaar" someplace south of Cairo, I came
across a guy sitting
on the floor of his small "shop" - about 2m wide by 3m long - no
door. He was sitting on the floor - a piece of "chipboard" with two
lumps of thick plywood
screwed/nailed to the ends - between which he had an electric motor
commutator (ex washing machine by the look of it) held between two
woodscrews (not sure if the pitch was metric or imperial - probably
metric if you go by percentages :-)) He was truing the commutator
with a VERY crude cutting tool - a simple bow with a string line
across the shaft producing the rotation using his left foot. These
commutators were IMMACULATE - I doubt if I could machine copper to
this level on my crappy chinese lathe!

To this end, there just HAS to be a SIMPLE solution to this that
requires no leadscrews/steppers/geckos/Mach2/3/4/5/6/7/8/9/10^10,EMC/
ECM/PDM/VC/VD or scar or other extraneous pieces of firmware/
hardware to produce - falls down from soapbox :-)

Cheers

Neil

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Neil D. Gillies Tel: +44 (0)
1383-823489
iGull.co.uk Mobile: +44 (0)
771-4330793
11 River View
neil@...
Dalgety Bay, Fife http://
www.igull.co.uk
Scotland KY11 9YE http://www.sea-
gull.demon.co.uk