Joe, Very good job. Like others I've tried to drum this into my
customers heads for years now.
I'm going to bookmark and pass along your design tips to my customers.
One thing you forgot is the section on paying on time, and how this will
get you lots of favors from the shop owner! :)
<One thing you forgot is the section on paying on time, and how this
get you lots of favors from the shop owner! :) >
Good point Steve! I meant to add that to the Do's and Don'ts section.
Thanks for the comments.
I am a departmental machinist at a university. I've been thinking about
doing this for our students for a long time and now I don't have to. I
would suggest showing examples of good drawings for both mill *and*
lathe parts. Maybe I missed it but did you mention dimensioning from
*one* reference point? Did you also announce this at
<Maybe I missed it but did you mention dimensioning from
*one* reference point? Did you also announce this at
Thanks for the comments Randy, I just added the dimensioning section
and posted to rec.crafts.metalworking.
If graduate students learn the way apprentices do, you should print out a
copy (in a big font size) and whack them over the head with it when they
first start requesting machined parts for their projects.
Put the print out in a three-ring binder if you're feeling particularly
pissed off that day.
I haven't yet had time to read the whole thing; but it looks like a VERY
impressive piece of
work. Is this something your customers have requested or are expecting? Is it
grown out of discussions that customers have welcomed, and that they want to
have expanded? The
reason I ask is that, in many cases, I'd expect customers to be a bit PO'd by a
them how to design parts - unless there's been some good "lead-in" of some kind.
Just to offer an analogy: If you went to a car dealer to buy a new car, and
told the salesman
you were looking for good gas mileage, and if the salesman started telling you
that he'd seen you
drive into the parking lot, and you were doing it all wrong, and here's how you
really ought to be
accelerating, shifting gears, and using the brakes... You'd probably turn
around and leave. You've
been driving for years. You know what you're doing. And what makes this
salesmand think he knows
more than you do about how to drive your own car?
If, on the other hand, you were ask some specific questions of someone you
knew and respected,
and if that someone answered your questions, and then offered to elaborate, and
to give you a whole
set of useful tips as part of the same conversation, you might be more than
willing to learn some
The difference between helpful advice and "You're an idiot - let me tell you
how to do it" is
often just a matter of presentation, even if the actual advice is identical.
That said, I hope your customers read and pay attention. The part of your
work that I did look
at seemed excellent, well written, and surely valuable in many situations.
I did see an error, though. In the first section, "DRAWINGS AND PRINTS", in
titled "When possible, use solid modeling to create complex part design", the 2D
drawing is wrong.
If the contour is in the side of the part closest to the viewer in the "face"
view, then it will
appear as hidden lines at the bottom edge of the side views. As drawn, you have
appearing on the front of the part when looking at the face, and on the opposite
side in the other
views. Since the focus is on drawing good prints, I figure you'll want to fix
one that's literally
impossible to read.
Do you intend to publish this? Have you shown it to anyone at a trade
school or an engineering
college? This could be something with a LOT of potential applications, and with
very wide appeal!
Good luck with it, and thanks for sharing.
I'm sick of spam.
The 2 in my address doesn't belong there.
Kirk, this would depend on the projection angle, would it not? That
drawing is prefectly correct if using ISO E projection angle. As another
point to Joe, the Projection Angle should always be noted in the border.
Our has an actual projection in the upper left corner so you can see how
the part is rolled through the views.
You can't 'idiot proof' anything....every time you try, they just make
True enough. There are different ways to project a drawing. But in my
experience, in the US,
in this century (and most of the last), anything not specifically and loudly
call out differently is
always, necessarily, assumed to be one type of projection only.
One of the cool things about 2D drawings derived from solid models is that
you can usually switch the 2D representation between ISO and ANSI on the
fly. Missler does it transparently. So do CATIA and UG. I think it takes a
third party add on to get this functionality in SolidWorks but I don't know.
This sort of thing can be useful when you send your 1st angle stuff out for
bids in a 3rd angle world and it's one of those things that goes unnoticed
until you notice it - usually as a screwed up thing-a-ma bob.
John R. Carroll
Machining Solution Software, Inc.
Thanks for the note. I wrote the section mostly because of the
questions I'd received from customers. These came from beginning
designers, up to experienced Ph.D.s. People always wanted to know how
to design parts in order to reduce the cost of machining.
I haven't received any negative feedback from customers. In fact, to
date, I've received a number of positive comments. The two folks I
quote on my links page (http://www.omwcorp.com/links.shtml) are both
customers who wrote me unsolicited emails and agreed to let me publish
their comments. Both are very experienced engineers.
I've gotten at least one or two new customers already who mentioned
they had read the section before they brought the job in.
Now it may be that some customers are annoyed by the work. I did have a
customer once a year or two ago write me an email that said "a
machinist should never question the design of a degreed engineer"
(seriously!:-)), but this customer was not a very good one. It seems
that the more experienced and talented the designer is, the more they
know that they don't know everything, and they seem grateful for any
advice. I personally like getting advice too, although as you mention,
it's nice to get some positive feedback at the same time.
Anyway, if you see any comments in the work that raise your eyebrows,
let me know and I'll be happy to tone them down.
In regards to the drawing views, I just used the quick Solidworks
default views that came up. I think they might be first angle
I'm hoping the work will get passed around at some institutions. Some
of the responders to my posts (I've posted a note on several
newsgroups) have said they are going to forward it on. I'm an adjunct
faculty member myself in Metal Technology at the College of Marin, for
what it is worth.
Thanks again Kirk. You're the guy who should publish a book! Your posts
are always fantastic!
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