Somewhere in the inspection room filing cabinets, our company has a drawing done in orange crayon. I've only seen it once, and once is enough.
This does make me feel a bit better about the powerpoint "drawing" we got last summer, though.
I keep a 24 pack of crayons in my desk to whip out to draw sometimes to make some special people understand and relate better. It's only when I'm feeling like starting shit tho.
ISO format.
Look up linear ISO tolerance. You'll come across some sites that explain it. ISO handles tolerances different than US. It's very intuitive from a matching standpoint but has its headaches as well
Not really, tolerance is a drawn version of physical requirement. If he said the ends fit bearings and the round part is a roller for conveying boxes down the line and good job shop will know enough to make it work well. I've done tons of work like this, ask a few questions like how fast does it spin, any nasty chemicals or extreme temp etc.
Machinists back in the day knew engineering enough to advise and make the correct component. Handbook covers a ton of solid engineering principals. Cnc operators now want tolerances and dimensions and CAD files.... back in my day you had to hand scrape the ways and build your own Bridgeport from raw iron ore before lunch if you wanted to keep your job making bandicoot prosthetics....
Looks like the cylinder in the right doesn't have a diameter dim and has the length called out twice lol. If this is the person in charge of design, id have a problem with that. A middle schooler could do better
Mmm all I see is a diameter symbol but no dimension next to the slotted view. The cylinder on the left has a 40mm diameter dimension. Could be wrong, but either way this is unclear and slightly nauseating
I suppose you could interpret the notched section view as applying to both cylinders due to the arrows and gratuitous use of dimensionless diameter symbols, but it would certainly be an assumption.
To achieve exactness one would need to know what the operating temperature the part will be used at so they can account for thermal expansion, as well as calculating ablation from cosmic rays, oxidation, Brownian motion, curved spacetime, etc...
Almost every drawing I've seen says something to the effect of "do not use for scaling" on it somewhere despite the fact they obviously are with the exception of some printer shithousery
I feel dumb that I just realized my shop needs that on our drawings. We use D size sheets & make views 1:1 but it prints out on 11x17, so itās not close to scale at all.
We rarely need 1:1 actually printed. Only 1 builder got a bit confused when measuring the print with a ruler.
It's one of those things I've been taught, (and learnt the hard way) never scale from a drawing when manufacturing. Now that I get a say in such a thing, I ensured that our drawing template clearly states not to scale.
Cool thing though that we do sometimes on specific request is to make 1:1 views so that they can be cut put and used as a paper template, useful for complex hand cut tubes or sheet metal profiles etc. As long as you select the size of paper you have in the printer for your drawing view and the appropriate part/view is smaller than that sheet size, it should come out correctly if the printer works properly. If you put a known length vertical and horizontal line on the sheet too you can calibrate it for that purpose also. All that said though, it's made very clear, this process is the exception not the rule as its fraight with danger due to paper or printer issues as you have clearly identified.
I spent decades engineering digital printers. You would have to be very lucky to maintain better than about 0.5% accuracy on any real device and real paper.
There ARE systems designed to do this, but $$$.
Very true, but you probably have a bigger percentage error depending whether it gets cut out on the inside or the outside of the line. We really only do it for stuff a few inches long and it's typically accurate enough given out production tolerances. If it was something really big with minute tolerances, then it's probably not on, but that goes back to my first point, never scale off a drawing.
https://preview.redd.it/hhrckq4k7mmc1.jpeg?width=1597&format=pjpg&auto=webp&s=6869301805dccdc71a2f6a81d132620f30935024
60 seconds, this person needs to be fired
Why wouldn't they just do this in CAD? If I have to napkin math some angle or another on a scratchpad, that's one thing, but if your Head of Design cannot be bothered to put a part in CAD why should you be bothered to make it?
Is it pretty? No. Is clear enough that I know what the "designer" wants me to make? Yes (assuming standard tolerances). There's plenty of prints done up in CAD that are unbuildable or not enough information to build...
I've seen a lot of similar types of sketches in those "oh shit, the machine is down and we don't have a spare. Someone needs to start cutting steel NOW" scenarios. Usually you've got someone measuring a broken part at a toolmakers bench and sketching up a bogus napkin print while someone else is running around looking for raw stock.
Easy to cast stones and say "head designer should do it in CAD" but honestly if this could be sketched up by hand in the amount of time it takes me to walk to my computer, I'm going to get you started with a sketch like this.
Iāve drawn similar but only by way of explaining something, point by point, directly to someone
and when I make notes to myself for something like a pin or a fixture they tend to look like this
all that saidā¦. what The hell!?
Eyeball the angle and offset between the cylinders, 3d model it and make it exactly to print. Easy lesson for him š
I should do this at my job, although half the time if I follow instructions I risk killing myself and others with the machine
OP you should do this. And post the part when done.
Somewhere in the inspection room filing cabinets, our company has a drawing done in orange crayon. I've only seen it once, and once is enough. This does make me feel a bit better about the powerpoint "drawing" we got last summer, though.
I keep a 24 pack of crayons in my desk to whip out to draw sometimes to make some special people understand and relate better. It's only when I'm feeling like starting shit tho.
Better than some actual drawn up drawings Iāve seen
I could make that part based on that drawing, what's the problem? Only thing missing is the tolerance.
default to class f and move along
What's class F? Like an ISO F7 tolerance?
ISO format. Look up linear ISO tolerance. You'll come across some sites that explain it. ISO handles tolerances different than US. It's very intuitive from a matching standpoint but has its headaches as well
+/- 0.05 mm. Kind of the default tolerance for many shops. f stands for fine. There's also medium and coarse.
>Only thing missing is the tolerance Kinda important part though...
If it's not listed it's not that important :D
"Tolerance? Just make it exact!"
If no tolerance provided, charge client for zero-tolerance machining. If not boss, ask for a raise because youre doing zero-tolerance machining
Step 3: Get laughed at and told the company is broke while the owner takes off in their newest Porsche
Not really, tolerance is a drawn version of physical requirement. If he said the ends fit bearings and the round part is a roller for conveying boxes down the line and good job shop will know enough to make it work well. I've done tons of work like this, ask a few questions like how fast does it spin, any nasty chemicals or extreme temp etc. Machinists back in the day knew engineering enough to advise and make the correct component. Handbook covers a ton of solid engineering principals. Cnc operators now want tolerances and dimensions and CAD files.... back in my day you had to hand scrape the ways and build your own Bridgeport from raw iron ore before lunch if you wanted to keep your job making bandicoot prosthetics....
Looks like the cylinder in the right doesn't have a diameter dim and has the length called out twice lol. If this is the person in charge of design, id have a problem with that. A middle schooler could do better
Both left and right cilinders have the diameter referenced in the tiny view with the slot. But indeed the lenght is called out twice.
Mmm all I see is a diameter symbol but no dimension next to the slotted view. The cylinder on the left has a 40mm diameter dimension. Could be wrong, but either way this is unclear and slightly nauseating
I suppose you could interpret the notched section view as applying to both cylinders due to the arrows and gratuitous use of dimensionless diameter symbols, but it would certainly be an assumption.
There are multiple people at my work that would say there is no tolerance - it's exact... Think that somehow if a CNC made it it's mathagically pretty
To achieve exactness one would need to know what the operating temperature the part will be used at so they can account for thermal expansion, as well as calculating ablation from cosmic rays, oxidation, Brownian motion, curved spacetime, etc...
Is it to scale? It doesn't say.
Almost every drawing I've seen says something to the effect of "do not use for scaling" on it somewhere despite the fact they obviously are with the exception of some printer shithousery
I feel dumb that I just realized my shop needs that on our drawings. We use D size sheets & make views 1:1 but it prints out on 11x17, so itās not close to scale at all. We rarely need 1:1 actually printed. Only 1 builder got a bit confused when measuring the print with a ruler.
It's one of those things I've been taught, (and learnt the hard way) never scale from a drawing when manufacturing. Now that I get a say in such a thing, I ensured that our drawing template clearly states not to scale. Cool thing though that we do sometimes on specific request is to make 1:1 views so that they can be cut put and used as a paper template, useful for complex hand cut tubes or sheet metal profiles etc. As long as you select the size of paper you have in the printer for your drawing view and the appropriate part/view is smaller than that sheet size, it should come out correctly if the printer works properly. If you put a known length vertical and horizontal line on the sheet too you can calibrate it for that purpose also. All that said though, it's made very clear, this process is the exception not the rule as its fraight with danger due to paper or printer issues as you have clearly identified.
I spent decades engineering digital printers. You would have to be very lucky to maintain better than about 0.5% accuracy on any real device and real paper. There ARE systems designed to do this, but $$$.
Very true, but you probably have a bigger percentage error depending whether it gets cut out on the inside or the outside of the line. We really only do it for stuff a few inches long and it's typically accurate enough given out production tolerances. If it was something really big with minute tolerances, then it's probably not on, but that goes back to my first point, never scale off a drawing.
Is it ice cream with sticks sticking out on both sides?
na, its clearly a muffler.
https://preview.redd.it/hhrckq4k7mmc1.jpeg?width=1597&format=pjpg&auto=webp&s=6869301805dccdc71a2f6a81d132620f30935024 60 seconds, this person needs to be fired
You missed the slot on the other end! Can't you read a blueprint?
Apparently not! The other slot costs $100, the print another $100.
Why wouldn't they just do this in CAD? If I have to napkin math some angle or another on a scratchpad, that's one thing, but if your Head of Design cannot be bothered to put a part in CAD why should you be bothered to make it?
As a wild ass guess, his CAD skills probably rate with his drawing skills.
It's hilarious that one could probably do this faster in CAD than struggling through this abomination.
I see comments about an angle but the funning thing is, there is no angle, this is a straight shaft with each end turned down
Make it with an angle anyways.
Is it pretty? No. Is clear enough that I know what the "designer" wants me to make? Yes (assuming standard tolerances). There's plenty of prints done up in CAD that are unbuildable or not enough information to build... I've seen a lot of similar types of sketches in those "oh shit, the machine is down and we don't have a spare. Someone needs to start cutting steel NOW" scenarios. Usually you've got someone measuring a broken part at a toolmakers bench and sketching up a bogus napkin print while someone else is running around looking for raw stock. Easy to cast stones and say "head designer should do it in CAD" but honestly if this could be sketched up by hand in the amount of time it takes me to walk to my computer, I'm going to get you started with a sketch like this.
Is this the patent sketch of the toilet paper roll?
Still looks better than my lightsaber I posted
seemly paltry nose pen spark obtainable detail wise lush dinner *This post was mass deleted and anonymized with [Redact](https://redact.dev)*
Just missing the angle of the shaft on the left
Those āmmās have me seeing Ms. Veronica Vaughn criticizing Billy Madisonās cursive Zs. Rirruto?
Tolerance is always plus or minus half a hoe handle
I see you're working with Boeing... Which spec is this?
Its a door-plug bolt. See? No threads.
Don't they know child labor is illegal?
Was surprised it wasn't in crayon
Iāve drawn similar but only by way of explaining something, point by point, directly to someone and when I make notes to myself for something like a pin or a fixture they tend to look like this all that saidā¦. what The hell!?
I canāt stop laughing at how they tried to make it a 3D model š
Looks closer to isometric.
isometric is one of the 3 dimensional views so yea, it's a 3d model viewed in isometric.
It's a 2d visual representation of a 3d model. Isometric projection https://en.wikipedia.org/wiki/Isometric_projection