Help with a 1960's era drawing call out...

I've been working on drawings since the mid 1980's and I haven't come across this one yet...

Anyone ever see a call out on a print like the one below? This print is from the '60 and it points to a few surfaces and a bore. I'm thinking it might be some kind of burr call-out? The mating part calls out the same symbol on the mating shaft and face. All the same surfaces indicated by this also have the normal 32 surface finish call out, so it's not that.

___B___ ___15___ / \/\/ / | / |/__

I tried searching the web, but came up short...any ideas?

Thanks

IYM

Reply to
IYM
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Well, even with the free pass I still wouldn't "just" ignore that callout without thinking it through first. Look at the names in the title box, and see if you can track down any of the original engineers or designers of the device - ask them what the heck it means.

Get the details of what this part is supposed to do and how it goes together, and have their engineers think it through as if they were designing it new. If it makes sense to do a radius break on that corner, you want to do it - AIUI, a knife-edge corner is a real good place to start a crack, where a nice radius edge spreads the stresses around _just_ enough to keep it from starting...

And if this is for aircraft or medical use, you'll be in BIG trouble not following the print, especially when it fails and kills someone - The FAA or the FDA is going to want to know the exact parentage of that part that failed. And they'll be looking for blood.

Good theory, it's possible - but more likely that the origin of the callout is simply lost in the mists of time.

"Never ascribe to Malice what can easily be written off as Stupidity."

If they walk in and see Brown M&M's in the bowl, that is a Red Flag to make sure the promoter has the right risers on the stage, the right microphones and band amps, the right mix board and house sound system, and all the other myrtiad details are complete and correct.

And if they aren't, THEN they have an perfectly valid reason to storm out and cancel the gig - The band usally arrives the morning of the show or at best a day ahead, and there is simply no time to fix it if the Promoter has deliberately not followed the contract.

There are many unscrupulous promoters out there who will cut corners ruthlessly to make more money from staging the concert, to the point where the band sounds like crap, looks like crap and the reviewers can't help but notrice and tell the world that the band has "lost their groove thang"... And guess whose reputation takes a hit? (Hint: It 's the band, NOT the promoter.)

If the band contract calls out for specific models of Sennheiser or Blue or other specialty vocal mikes that capture their voices best, and they walk in and see the Promoter has rented them a row of beat-up old Shure 57's for primary singers and a bunch of Shotguns for the backup singers, that is going to be trouble. Yes, they will "work", but they are not the best fit for many voices and will make you sound horrid - they will amplify any faults in your voice.

In the same spirit, they will cut corners on the speaker stacks, the amps, the mixing board (an old Nady instead of the big Yamaha the specs called for) the lighting, the effects, the Stage Security and controlling the Access Passes...

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Reply to
Bruce L. Bergman

Have to try the nursing home - lol... Some of the other components calling out the same symbol have a 1953 dwn date...On the basis that the engineer/designer/draftsman were around say 30 years old around that time, that would put them in their late 70's or 80's, well past retirement. I don't think there is anyone there from that era anymore. Also, the prints were acquired by our customer in the 1980's when the original company was acquired (I believe), so the paper trail to find someone gets a little muddy..

The problem is that all the things you mention are all on the print too. Radius, chamfers, surface finishes are all called out. (The leader is not pointing to edges but to surfaces.)...and besides, come on - we would never leave a knife edge (unless otherwise specified - and even then the guys on the shop floor would be coming in giving me crap about that! - lol)

(BTW - for the other poster - It's a moving part - no welds whatsoever)

yup - We've been mfg aircraft and medical parts for 30 years, so we kind of know. We don't fool around.

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Reply to
IYM

This is a long shot, but my first reaction was that it was a callout for the lay and direction of the finish texture. I've seen those in mold work and sometimes on bearing surfaces, but my books don't show that one. It's possible.

Reply to
Ed Huntress

Nor would I.

Check the mating parts, if any. It still has to mate, right?

And to get dinged in shippping & assembly, etc. Or even prevent assembly.

If there are even older versions of the print one might have a note of adding that callout. Might.

Reply to
Cliff

IIRC The /\/ on the label leader indicates an edge break & R indicates radius while no R indicates a chamfer break. But don't hold me to it.

Reply to
Cliff

What does it move relative to at all those locations?

Reply to
Cliff

Give a copy of the print *as is* to jb to make. Then don't do what he did.

Problem solved.

Reply to
Cliff

So? Track a few bodies down, if they are retired from the client company their Payroll Department had better know where they are sending the retirement checks...

Call. Or if you are close, stop by, and bring their favorite libation... You might be pleasantly surprised how much you get when you pick their brains.

Including "Oh, THAT part! Did they give you the print for the A revision, or the C Revision? We had a crash and traced the failure back to the A Revision part, we totally redesigned it in 1960."

(And then you look, and you were indeed going to make a batch of a known bad design off the A Revision print, because someone at the office didn't dig into the old files deep enough...)

The joys of a lack of corporate continuity - having a few old farts hang around who remember where all the bodies are buried, and can show the young bucks that there are /far/ better ways to get things done than a brute-force frontal assault.

But the Accountants can't let that happen - they hire for the project and fire as soon as it's over.

I figured you knew, but it never hurts to restate the obvious - just in case Transient CRS happened.

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Reply to
Bruce L. Bergman

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