Another Drawing Discrepancy thread....

[dkmc]

Part consists of laser cut rings, months ago when I got the drawing to quote the OD was 6". Shortly after (like 2 hours) I got it, my intermediate guy sends an email...'Well they already changed the OD to 6.5". I quote, get the PO and produce the quan. 6 pcs. All is well. FFD 4 months, email from intermediate..."They need 6 more of these rings, you did them before, checking current pricing".
I quote again with modest price increase due to increase from laser house. Blanks come in, I set to work on the parts. Put a blank in the lathe, measure OD, look at the drawing sent with current PO......OD is 6.625. WTF? Measure blank again......wait for it.....Check Rev. number and Description box on drawing. Same drawing No., same Rev, no notes as to OD change, etc.

I email intermediate with no response. Couple days later I speak to them in person...."Yea didn't see that either". Can you re-order the material? I mention, "I think you need to talk with them, and let them know about this problem, the material cost is about 50% of the profit in the job. Not going to be cost effective for me to eat the replacement cost". They are 'checking' to see of customer can also use the smaller OD parts....as of about 2 weeks ago. No further developments.

Who's at fault here......?
My thoughts: Partly my fault for not looking at the drawing, totally forgot about the 6" to 6.5" OD change initially 4 months prior. Actually did and always do glance at Rev# and discription box on drawing, but didn't scan all dimensions. The 'You did these before' line helped make me lazy and think I was making the parts "Same as before". I don't blame intermediate, but think they need to go back to their customer. I also sent intermediate blanket email with wording about me not being responsible for changes not called out verbally as well as alerts via email and changes to revision numbers and notes on drawings........AS PER standard engineering/ mechanical drawing practice 101. IOW.....whoever made the change and didn't tell anyone needs proper reprimand.
Long winded story for simple SNAFU.

 

[DanASM]

That does suck, but its up to you to make the part that is on the print they gave you for the job. Mistakes happen and can get costly. Everytime I make a mistake that cost me $ I say to myself "thats the price of tuition".

I have spent way less than people who go to college, and probably know more. It helps me learn from my mistakes faster when it cost me real $.

 

[DanielG]

I disagree with Dan. This one's on the customer. They didn't rev the drawing. You had no good way to tell if anything was different.

 

[deftonite]

I have spent way less than people who go to college, and probably know more.

The smartest people I've worked with all had a common trait: they acknowledge that they only know a little. You might consider being more open to those college folks.

In this case, Dan is incorrect as the drawing is invalid. The customer has not implemented proper document control, and failed to freeze production-released drawings. Without a process to ensure past work is properly vaulted, this bullshit is surely to happen again. In this case DKMC's shop needs to charge more on future work from this customer to pay for someone to double check the customer's inputs match their intent.

 

[gustafson]

No document control, not my fault. If it says rev 2 I am making rev 2

 

[Matt@RFR]

No document control, not my fault. If it says rev 2 I am making rev 2

Bingo. Am I supposed to cross check all 159 dimensions on every job I get?

Nah.

 

[guythatbrews]

Yeah it's on the customer, although they might not agree.

I think we will see more and more of this sort of thing as untrained people are empowered by CAD. Although this seems very much a common sense issue. Maybe there is less of that also!

 

[dkmc]

That does suck, but its up to you to make the part that is on the print they gave you for the job.

True. It's also the responsibility of the engineer or CAD jockey to properly update the drawing information or at least call attention to changes, don't you think? If you do a job and it repeats a few times, then suddenly the drawing has a different dimension on it with no alert even at least verbally, you'd be OK with just making the parts over again? Or having to buy different material? I'm thinking your response might be different. I've screwed up many parts, and silently corrected my mistakes, but when changes come without warning or alert via drawing updates, that's not the way to do business IMO.

 

[morsetaper2]

I'm retired now, but in my working life I was the engr who designed the part, made the prints, sent prints out for quote, and then awarded the job.

If I had sent out that sort of print, the mistake would have been on me. Not the shop's fault. They (the customer) screwed up and should cover your time & matls on that oversight.

 

[Houdini]

I would say you both eat half, keeps both parties happy with owning they both f-ed up.
but also depends on your shop and customers, some shops majority of customers walk in with a part and say I need more of these but can you make this a little tighter, haha
or they just send cad models over without prints
...
...
So I think it depends on what you enforce consistently.

 

[DanASM]

True. It's also the responsibility of the engineer or CAD jockey to properly update the drawing information or at least call attention to changes, don't you think? If you do a job and it repeats a few times, then suddenly the drawing has a different dimension on it with no alert even at least verbally, you'd be OK with just making the parts over again? Or having to buy different material? I'm thinking your response might be different. I've screwed up many parts, and silently corrected my mistakes, but when changes come without warning or alert via drawing updates, that's not the way to do business IMO.

I get prints with every P.O. When setting the job up, I would notice the different dimensions on the print and then reach out to the customer to find out why. I wouldnt make any parts that werent made to the print that came in with the P.O.

I guess others operate differently, mistakes happen thats part of life. I hope you come up with a solution thats works for both of you.

 

[dkmc]

I would say you both eat half, keeps both parties happy with owning they both f-ed up.

Thanks for your feedback.
If I was the customer I'd gladly settle for half. But in my position I'm feeling about 10% at fault here. It's far from common practice to check every dimension on any drawing looking for changes. Common practice outlined prev. is standard procedure in regards to making engineering changes, which they failed to do. I'm not on board with the 'everybody get a trophy' and 'no one admits mistakes' way of thinking.

 

[boosted]

I have spent way less than people who go to college, and probably know more. It helps me learn from my mistakes faster when it cost me real $.

LOL. Good on ya, because I have spent way more than a normal college tuition educating myself through f--- ups.

 

[Freedommachine]

Ugh, that's an unpleasant situation to deal with no matter what. Hopefully they will make it up to you.

I could have (likely would have) fallen into the exact same trap. I mean, who doesn't update the Rev when they make drawing changes?

 

[dkmc]

I mean, who doesn't update the Rev when they make drawing changes?

Another CAD jockey from another customer years ago! Several different dimensions changed that I happened to notice while there delivering parts. The owner handed me the drawing and said they 'need 25 more of these'. I went in and checked with CJ on the changes, and said.....'no revision change or description of changes'?? He smugly says "I don't use revision numbers" in a condescending tone. I went thru the whole 'why' they are needed. Didn't matter. Then I told the owner of the potential problems.
When I came back with the 'another 25' group of parts made to the new drawing, CJ was ....gone. A much better CJ was in his place.

 

[SD&M]

I often feel better when I read these sorts of threads; it's not that I enjoy hearing of other's woes, but it makes me realize that we're not alone in having to deal with this sort of thing with some (thankfully few) of our customers!

Much of the prototype work we do is quoted and produced from 3D CAD data only, or from CAD data + CTF drawings only. Luckily, we often are dealing with the responsible engineer for this type of work and can usually get them on the phone/email/screen share quickly if additional clarification is needed. It's not unusual to work on successive revisions of the same basic part(s) + assemblies thru a number of design changes (most of this process happens with little or no revision control). Sometimes a part will change while we're working on it, even! We'll often compare the down-rev 3D CAD data with successive revs and catch differences that we might otherwise miss (and the engineers can't always recall what has changed either-LOL). I believe that Solidworks has a function for this, our CAD/CAM s/w (Topsolid) has a useful function for this, too. I agree that many customers need to improve their processes in this regard, but we *do* have tools to work with what we get!

I realize that most of us find this process onerous and risky, but as I see it there's also an opportunity to provide value above and beyond what many shops offer-save your customer's bacon a few times and it can help to cement a (possibly) valuable relationship. Admittedly, some customers will appreciate this, and others won't, but I can't recall a time in the last 10 years or so where any of us have had to resort to the blame game. Most problems have been avoided, and when somehow it's gone sideways it's been handled to everyone's mutual satisfaction. No major carnage....

Just another perspective....my 0.02$ worth!

 

[jccaclimber]

Changing a drawing without changing the REV is a massive no-no. A few years ago I sent a drawing with a giant “DO NOT PRODUCE, UNRELEASED” note on it. It was there because we were exchanging unreleased drawing for DFM. Get my part back and it’s an old REV. “You never sent us a new one, so we ignored the note, lots of customers have that note on samples.” I was able to rework myself, and my purchasing guy had failed to send the released drawing with the PO, so I ate that o e. I did have a conversation with the supplier about not making things that say “DON’T MAKE ME.” In giant capital letters.

A lot of the shops I work with, first thing they do is check the envelope dimensions of the drawing that came with the PO, doesn’t matter if it’s a repeat. It’s on the checklist (you have one of those right?) they do when they quote.
In this case I’d say you’re only 10% at fault. If the customer agrees to buy the existing parts they get a small CYA charge attached to future orders. How much larger of a future CYA surcharge they get depends on how much or little re$pon$ibility they accept on this.

I have had one shop give me (and not my coworkers) a PITA surcharge. It was better for both of us in the end. Eventually the surcharge they were putting on my parts got high enough that all of the other shops I had good experiences with (generally on time, to print) became cost effective, and they no longer had to deal with me.

 

[guythatbrews]

Changing a drawing without changing the REV is a massive no-no. A few years ago I sent a drawing with a giant “DO NOT PRODUCE, UNRELEASED” note on it. It was there because we were exchanging unreleased drawing for DFM. Get my part back and it’s an old REV. “You never sent us a new one, so we ignored the note, lots of customers have that note on samples.” I was able to rework myself, and my purchasing guy had failed to send the released drawing with the PO, so I ate that o e. I did have a conversation with the supplier about not making things that say “DON’T MAKE ME.” In giant capital letters.

A lot of the shops I work with, first thing they do is check the envelope dimensions of the drawing that came with the PO, doesn’t matter if it’s a repeat. It’s on the checklist (you have one of those right?) they do when they quote.
In this case I’d say you’re only 10% at fault. If the customer agrees to buy the existing parts they get a small CYA charge attached to future orders. How much larger of a future CYA surcharge they get depends on how much or little re$pon$ibility they accept on this.

I have had one shop give me (and not my coworkers) a PITA surcharge. It was better for both of us in the end. Eventually the surcharge they were putting on my parts got high enough that all of the other shops I had good experiences with (generally on time, to print) became cost effective, and they no longer had to deal with me.

Your first sentence is 100% correct. But I don't see the 10% logic. It might give you a warm fuzzy feeling to check a few "envelope dimensions", but unless you check every dimension it's a meaningless gesture.

When drawing changes are made the revision level must be changed, period. The maker bears no responsibility to check any dimensions if the rev level hasn't changed.

The only time I check dimensions is when I get a NEW rev level. Although all changes should be flagged with the new rev level, ommisions occur and I've no standing to complain if the new rev is indicated on the PO. So, drawings side-by-side, every unchanged detail is highlighted on the old rev, while every changed detail is highlighted on the new rev. Simple, effective process, and fully documented. The old rev drawing is heavily marked obsolete. With many dimensions it takes a tedious while, but not nearly as long as making new parts!

When you sent out a drawing with the "unreleased do not produce note" and the drawingless new rev PO later, your vendor should have gotten written approval to use the unreleased drawing with the old rev level. He didn't do so and thus was 100% culpable.

There are no gray areas here. Everyone has to step up with due diligence and bear responsibilty to correct their own mistakes. It may hurt but that is the way it is.

If with a little effort you can play the hero for a good customer, great. But let them know it's a one-time deal. After all, few customers will take it on themselves to fix parts made to and old rev level, and why should they?

 

[jccaclimber]

The 10% logic comes from the fact that at the end of the day I don’t trust people outside of my control. It’s easy to say “this was zero percent my fault”, but that also implies there was nothing reasonable you could do to prevent it from happening again. I used to work with a drafter who would randomly change a single tolerance halfway across the drawing when editing something else for me. These were drawings the size of my desk with a huge number of dimensions. My solution was to set up a light table and check everything every time. PITA, and something that I should not have needed to do, but it was better than the alternative. Once you know something can happen and have a way to avoid it you are no longer zero percent at fault IMO.

 

[guythatbrews]

Once you know something can happen and have a way to avoid it you are no longer zero percent at fault IMO.

The drafter was under your control so that was 100% on you and you took responsibility, as you should! The problem arises when the customer doesn't take responsibility in like fashion.

Once you know something can happen and have a way to avoid it you are no longer zero percent at fault IMO.

Maybe just a bit of hyperbole here? It's unreasonable to believe you can fix everyone elses mistakes. It's tough enough to get stuff done when I cover all my bases, let alone everyone elses. Again, do any of your customers accept any % responsibility to fix non-conforming parts? Mine never have. A customer or vendor that consistently provides bad info and expects no repercussions is not a good customer. I let 'em go.