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Whoa, he just photoshoped technical drawings of a DB-25? Surely if you're doing a group buy worth that much money a) somebody in the group buy has the technica

by Niksko 10y ago

Whoa, he just photoshoped technical drawings of a DB-25? Surely if you're doing a group buy worth that much money a) somebody in the group buy has the technical skills to do a proper drawing, or b) you can spend a tiny amount of money to get proper drawings made. I mean, it worked out in the end. But it seems like a giant case of Dunning-Kruger to think "Well I don't know how to make technical drawings, therefore photoshopping an existing drawing shouldn't present any problems".

Aloha 10y ago
I work for a company that manufactures things, its very common to edit paper drawings (with pen) or photoshop a digital one for which the source file has been lost, its not that hard to get it right.
- Gibbon1 10y ago
  Just remembered, back in the late 90's went to a board house for some reason and one of their techs was in the middle of recreating gerbers for a PCB off a xerox of the top and bottom side of the PCB.
- cnvogel 10y ago
  ...and most rules for how to get a mech. drawing right are from the times when computer design didn't exist anyway.
ghshephard 10y ago
I'm wondering what the difference is between photoshopping versus using a CAD tool? As long as the dimensions are correct, I would think that the end-result would be identical from the perspective of the manufacturer. Heck, there was a time in which these things were generated with pen/pencil/ruler, and the manufacturer was able to work fine off those drawings. Whatever tool you are competent with, is probably the correct one to use in these types of situations.
- Gibbon1 10y ago
  One issue is that the manufacturer often has to convert the part drawing to a set of drawings for the tooling. That means they need to adapt the dimensions to their particular processes. In the case of a DB-19 the company likely has a cad drawing of a similar part they can adjust.
- PhasmaFelis 10y ago
  I would guess that none of the people involved had experience with CAD work, which makes it tricky to spot your own mistakes. If you work from someone else's template, you can be somewhat more confident that you're doing it right.
lb1lf 10y ago
Do keep in mind this was a DB19, and presumably the manufacturer already made other connectors in the same family; hence they had a fair idea how all of the detail not obvious from the supplied drawing would be. Fair guess - they took a DB9 drawing and inserted additional pins using whatever CAD system they were using, then entered production. I haven't soldered anything but DB9s in later years, but I am pretty confident both pitch and edge shape is identical on DB9, DB15 and DB19. (I have a vague recollection DB25 is slightly closer pitched, but may well be mistaken.) That being said, one can never supply too much information to a supplier - if nothing else to be able to shrug and say 'not to spec' when some seemingly irrelevant (to them) shortcut bungles your project...
- gdavisson 10y ago
  Technical correction: the proper designations are "DE-9" and either "DE-15" (if you're referring to the high-density three-row connector used for VGA) or "DA-15" (if you're referring to the original lower-density two-row 15-pin connector). The second letter referred to the shell size, so a DE-9 and DE-15 had different numbers of pins arranged in the same-sided shell. Wikipedia has a good section on this: https://en.wikipedia.org/wiki/D-subminiature#Description.2C_nomenclature.2C_and_variants https://en.wikipedia.org/wiki/D-subminiature#Description.2C_.... The so-called "DB-19", on the other hand, had a nonstandard shell size, so it doesn't really have a proper name under the original system. Maybe "Dx-19".
CamperBob2 10y ago
Easy to talk about how you'd do it, but I don't see any boxes of connectors in your living room. The factory is probably going to recreate the drawing in their own tools anyway, even if you send them a STEP file. They can use a sketch on a napkin for that purpose, as long as the critical dimensions and tolerances are stated.

by Niksko 10y ago

Aloha 10y ago

I work for a company that manufactures things, its very common to edit paper drawings (with pen) or photoshop a digital one for which the source file has been lost, its not that hard to get it right.

Gibbon1 10y ago
Just remembered, back in the late 90's went to a board house for some reason and one of their techs was in the middle of recreating gerbers for a PCB off a xerox of the top and bottom side of the PCB.
cnvogel 10y ago
...and most rules for how to get a mech. drawing right are from the times when computer design didn't exist anyway.

ghshephard 10y ago

I'm wondering what the difference is between photoshopping versus using a CAD tool? As long as the dimensions are correct, I would think that the end-result would be identical from the perspective of the manufacturer. Heck, there was a time in which these things were generated with pen/pencil/ruler, and the manufacturer was able to work fine off those drawings. Whatever tool you are competent with, is probably the correct one to use in these types of situations.

Gibbon1 10y ago
One issue is that the manufacturer often has to convert the part drawing to a set of drawings for the tooling. That means they need to adapt the dimensions to their particular processes. In the case of a DB-19 the company likely has a cad drawing of a similar part they can adjust.
PhasmaFelis 10y ago
I would guess that none of the people involved had experience with CAD work, which makes it tricky to spot your own mistakes. If you work from someone else's template, you can be somewhat more confident that you're doing it right.

lb1lf 10y ago

Do keep in mind this was a DB19, and presumably the manufacturer already made other connectors in the same family; hence they had a fair idea how all of the detail not obvious from the supplied drawing would be. Fair guess - they took a DB9 drawing and inserted additional pins using whatever CAD system they were using, then entered production. I haven't soldered anything but DB9s in later years, but I am pretty confident both pitch and edge shape is identical on DB9, DB15 and DB19. (I have a vague recollection DB25 is slightly closer pitched, but may well be mistaken.) That being said, one can never supply too much information to a supplier - if nothing else to be able to shrug and say 'not to spec' when some seemingly irrelevant (to them) shortcut bungles your project...

gdavisson 10y ago
Technical correction: the proper designations are "DE-9" and either "DE-15" (if you're referring to the high-density three-row connector used for VGA) or "DA-15" (if you're referring to the original lower-density two-row 15-pin connector). The second letter referred to the shell size, so a DE-9 and DE-15 had different numbers of pins arranged in the same-sided shell. Wikipedia has a good section on this: https://en.wikipedia.org/wiki/D-subminiature#Description.2C_nomenclature.2C_and_variants https://en.wikipedia.org/wiki/D-subminiature#Description.2C_.... The so-called "DB-19", on the other hand, had a nonstandard shell size, so it doesn't really have a proper name under the original system. Maybe "Dx-19".

CamperBob2 10y ago

Easy to talk about how you'd do it, but I don't see any boxes of connectors in your living room. The factory is probably going to recreate the drawing in their own tools anyway, even if you send them a STEP file. They can use a sketch on a napkin for that purpose, as long as the critical dimensions and tolerances are stated.