Machining tips 22

[ctopher]

Here is some good info for anyone that is either new to the profession, or need a refresher.

http://www.omwcorp.com/partdesign.html

Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 04-21-07)

 

[AnnaWood]

Chris,

Great web page....

Cheers,

Anna Wood
SW 2007 SP4.0, WinXP
Dell Precision 380, Pentium D940, 4 Gigs RAM, FX3450

http://designsmarter.typepad.com/solidmuse

http://www.phxswug.com

 

[PSE]

I know a few folks around here that could use such a review. Nice that they offer a .pdf as well. Thanks for posting it.

Regards,

 

[ajack1]

Nice link ctopher a star for you.

I am sure there will be the normal it is not a designers job to make the machinists job easy comments however.

 

[thixoguy]

As a former toolmaker who now works in design, the author has covered the topic very well.

Thanks for posting ctopher. Have a star

thixoguy

 

[ctopher]

Thanks.
I'm happy it works for everyone. It's great to have and to go back for reference often. A lot of good info in one place.

Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 04-21-07)

 

[ewh]

Great resource Chris! Have another star.
The only item that I take exception with is making the the inclusion of contact info on the drawing mandatory. This would be better included in the PO or related instructions. It would not be cost effective to incorporate a drawing change due to a personel change or a project handoff.

 

[Standing]

Chris,
A great reminder for us all. A star for you.

Bradley
SolidWorks Premim 2007 x64 SP4.0
PDM Works, Dell XPS Intel(R) Pentium(R) D CPU
3.00 GHz, 5 GB RAM, Virtual memory 12577 MB, nVidia 3400

 

[NickE]

I am sure there will be the normal it is not a designers job to make the machinists job easy

Ahhh... but it is the designers job to assure that the b/p reliably calls out the required features, that the b/p is unambiguous, and that the thing on the b/p is able to be manufactured.

 

[ewh]

... and if that is accomplished, the result makes life easier for the machinist. Therefore it is actually in the drafter/designers best interest to consider DFM.

 

[KENAT]

Chris, nice link. Haven't had a chance to look closely but only one thing really stood out as being what I'd consider bad advice:

The note on who to contact with questions should be a mandatory feature in any drawing!

Potentially very useful for prototypes (it's made me think about adding it as standard to our prototype stamp) but meaningless on production as staff change et. Also for production the machine shop should probably contact the purchaser on the PO or manufacturing engineer (especially in larger companies) not the designer/engineer directly etc.

I especially liked the section

Provide a dimensioned or semi-dimensioned 2D print, even when using solid modeling

this matches my limited experience in this area.

Ajack, normally I'd be the one saying that but I like what NickE put. When it is possible to make the machinists job easier without sacrificing part definition etc then we should, however part function and supporting inspection take priority. Plus, a lot of peoples attempts at 'making life easier for the machinists' don't, they just make life harder for inspection/ensuring function of the part! At the end of the day though we need to make sure the part can be made cost effectively.

KENAT, probably the least qualified checker you'll ever meet...

 

[ctopher]

Kenat,
I 100% agree with both.
Thanks for catching that!

Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 04-21-07)

 

[KENAT]

No problem, like I said overal it's really good, I've forwarded to several people internally. (ewh spotted the name thing first not me.)

I put a link to it and this thread in the mechanical area as I know it gets more traffic, hope you don't mind.

http://www.eng-tips.com/viewthread.cfm?qid=197410&page=1

KENAT, probably the least qualified checker you'll ever meet...

 

[ctopher]

I don't mind. I believe in sharing info.

Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 04-21-07)

 

[KENAT]

A colleague of mine pointed out that it didn't really mention GD&T.

What I did think is that pretty much if you fairly closely follow industry drawing standards then you meet a lot of the points in the link.

KENAT, probably the least qualified checker you'll ever meet...

 

[handleman]

Potentially very useful for prototypes (it's made me think about adding it as standard to our prototype stamp) but meaningless on production as staff change et. Also for production the machine shop should probably contact the purchaser on the PO or manufacturing engineer (especially in larger companies) not the designer/engineer directly etc.

I think this one is strongly context-dependent. If the context is product design, I agree. In the one-off, custom machinery world where entire project schedules are measured in weeks, the quicker a question on a print is addressed the better. When I issue a drawing for fabrication, it may go through three sets of hands inside my company before either the in-house or an outside shop gets it. As the machine designer, I am really the only one qualified to answer most questions. If the shop calls the PO issuer in the Purchasing department, who calls the guy in my Parts Aquisition department, who looks in his paperwork to figure out who made the drawing and finally gets to me, it can cause several days delay on getting my part completed. We never issue a drawing without contact information.

 

[KENAT]

handleman, agreed, I should have been more general than just saying protype, one off/limited production tooling etc it also applies.

However, the important thing is that it's not a one size fits all rule.

KENAT, probably the least qualified checker you'll ever meet...

 

[Heckler]

Super Star

Heckler
Sr. Mechanical Engineer
SWx 2007 SP 4.0 & Pro/E 2001
o
_`\(,_
(_)/ (_)

This post contains no political overtones or undertones for that matter and in no way represents the poster's political agenda.

 

[wes616]

The note on who to contact with questions should be a mandatory feature in any drawing!

Our standard title block has section for signoffs (design by/drawn by/engineer/check/appvd). I always put my telephone number under my name.

Wes C.
------------------------------
No trees were killed in the sending of this message, but a large number of electrons were terribly inconvenienced.

 

[Gymmeh]

ctopher, all your stars are maxed out!

Thanks its very usefull.