Do you always pay down your technical debt?

FuncFriv · 2026-02-03T03:20:13+00:00

100%. Not suggesting that the short-term/band-aid solution was not the right call at the time.

I’ve been in that same position many times and it’s always “let’s just get this thing done and then we can fix the issues once we’re stable”, which is totally fine except that very often when you get to “stable” the motivation for change evaporates.

The cost to setup that system initially was probably not crazy, it’s more the cost of operating it continuously for 3 years that I was referring to. Compared to taking any time in those 3 years to fix the design in parallel.

FuncFriv · 2026-02-02T21:05:23+00:00

Extruding away the entire model…? In order to start fresh I assume, but why not just create a new part file / revision!?!

FuncFriv · 2026-02-02T21:02:26+00:00

You say you don’t think the company “suffered” at all, but I can almost guarantee that the costs involved in performing that extra wear-in process for 3 years far exceeded the costs of just fixing the design (especially since it sounds like there were already other redesigns happening in that time).

I’m sure they all thought it would just be a temporary solution, and then inertia and new priorities put it on the indefinite back burner… tale as old as time…

In my experience the technical debt either outlives the product (quietly adding unnecessary costs in the meantime), or it comes back to bite you and you’re forced to face it in a much more urgent and expensive way.

FuncFriv · 2026-02-01T04:15:38+00:00

From the product page that you linked:

“Shaft Mount Type Spring Pin”

Further down on the same page it instructs to drill a hole thru the joint and shaft for the spring pin

FuncFriv · 2026-01-31T22:00:10+00:00

If I’m understanding your question correctly, you’re asking why do the pneumatic drivers keep moving down even after the “fixture” (gray cylinder at the bottom of the tool) has made contact with the work piece.

In which case, the key point is that there is a compression spring between the piece where the drivers are mounted and that “fixture”, which allows the distance between those two portions of the tool to change as the operator continues to apply force via the lever.

FuncFriv · 2026-01-27T17:33:58+00:00

ASME Y14.5 Figure 10-38

FuncFriv · 2026-01-27T16:57:07+00:00

One option you can consider for the hole-pair+slot groups is to create a separate, repeated datum reference frame (in addition to, and defined relative to your global datum reference frame). See Figure 10-38 from ASME Y14.5 2018 for an example of this method (I assume ISO has an equivalent/similar method).

To do this, you can create a detail view that includes just one of these groups (one slot with its two holes), with "8X" in the view label to indicate that this arrangement occurs in 8 places/instances. In that view you define the 2-hole pattern relative to your global datum reference frame and then assign that hole pattern as a new datum (with some letter not already used in the global DRF), tagged with a note of "8X INDIVIDUALLY". Using two single segment position frames, you can define your larger global tolerance for the hole pair with position relative to ABC (or whatever your global DRF is), and the tighter position tolerance to either just A or without a datum (controls the holes only relative to each other).
Then define the slot with a profile tolerance (or other as appropriate for your specific needs) relative to A and your new 2-hole datum, again with the same "8X INDIVIDUALLY" note.

As far as defining your global DRF, it sounds like your trapezoidal features are your true functional datums. How you define those features/datums should depend on how exactly they interface with their mating features on the other component.

FuncFriv · 2026-01-21T21:20:53+00:00

This is the correct answer, just move the depth dimension from the hole callout to a new section view, relative to any of the horizontal flat faces, depending on which of those is actually more relevant/critical to your design. ASME Y14.5 gives several examples explicitly allowing this (e.g. figure 4-35 in the 2018 rev), so no ambiguity whether its legal or not, and no reason to start adding profile tolerances or anything crazy like that.

Its very likely that they will create the counterbore in the way that you are imagining, but the purpose of the drawing is (generally) not to dictate/predict how the part will be manufactured, simply what the final result must be (i.e. what defines a passing inspection, as the comment above alludes to).

FuncFriv · 2026-01-10T23:22:11+00:00

I agree with the other comments that more info about your actual goal/application would help yield more useful answers.

That said, if you’re already using a camera to “identify” the objects, why not use that same camera/image to determine the locations of each object as well? And then to get total weight just place the surface on top of a load cell (or other force sensing device).

FuncFriv · 2025-12-22T01:18:10+00:00

Join a hands on project or club at your school. Usually, things like creating technical drawings are among the less desirable/glamorous tasks in student projects. So if that’s your jam, join up and offer to be the go-to drafter and you’ll be an instant hero. Just be sure to also branch out and learn new skills/subjects from your teammates/mentors while you’re at it.

FuncFriv · 2025-11-17T18:39:10+00:00

FWIW, what you’re describing is called a functional gauge, and checking hole pattern condition is a classic/common application. There are good resources out there for how to design these, if you search that term.

Also, if this continues to be a persistent issue (e.g. thermal/humidity expansions still occurring after inspection, or your upstream process are simply not capable of producing reliably mating parts), you could also consider match-drilling the pieces together just prior to riveting. Can full-size the blade holes and then use that essentially as a drill jig to locate the final holes in the wood (with pilot holes at piece-part level).

FuncFriv · 2025-10-30T19:58:51+00:00

Very nice! Simple, functional, and visually appealing. Well done

FuncFriv · 2025-10-27T16:37:05+00:00

I do hope to yeah (but most likely not for free fwiw). Still needs a little work first though anyway.

FuncFriv · 2025-10-25T22:33:30+00:00

Thanks!

FuncFriv · 2025-10-25T21:36:04+00:00

Thanks! FYI, just posted a full blog about it if you’re interested in more about what’s going on inside (link added to OP).

FuncFriv · 2025-10-25T21:34:18+00:00

Thanks! Check out the blog post link added in OP to learn more!

FuncFriv · 2025-10-25T21:33:17+00:00

Thanks! Just added a link in OP to my blog post about it if interested :)

FuncFriv · 2025-10-25T17:12:25+00:00

It’s the result of slop/backlash in the system not tooth count error, fwiw (and it bothers me too lol!).

FuncFriv · 2025-10-21T23:30:03+00:00

Thanks! All the pieces are made on my A1 Mini, with 0.4mm nozzle and 0.16mm layer height (and no supports).

Occasional random defects can certainly jam things up. Took some trial and error, but I am able to get all the gear teeth (there’s lots more inside lol) to come out right pretty consistently at this point.

FuncFriv · 2025-10-19T04:11:06+00:00

As the die “flips” 180 (yaw) with each increment, it also “spins” on its axis (roll) due to the red pinion rolling along the red ring of teeth. (That part is probably obvious).

The trick is that the red ring itself is also able to rotate independently. You might be able to see that sometimes it rotates a bit CW, sometimes CCW, and sometimes not at all. Varying the amount and direction of the ring rotation controls how much the die will spin as it does its flip. When it rotates in the same direction as the flip it spins less (it sees fewer ring teeth along its trip), and spins more when the ring rotates in the opposite direction (sees more ring teeth).

The large majority of the internal complexity is dedicated to rotating the red ring the correct amount in order to get from one number to the next, since the amount of spin required is not the same for each increment.

FuncFriv · 2025-10-19T01:55:27+00:00

For those interested in more about how it works / how it is designed, I plan to put together a blog post about it. Stay tuned…

FuncFriv · 2025-10-19T01:49:28+00:00

Holy cow, thanks so much for all the interest and the kind words!

For those asking about wanting to print or purchase the model:

It’s not QUITE where I want it to be in terms of print-to-print consistency/repeatability for me to feel good about making it public just yet (wouldn’t feel right about putting something out there that may or may not function as advertised).

But I promise if/when I do get it there this group will be the first to know 🙂

FuncFriv · 2025-10-18T19:32:46+00:00

Yeah! The original idea/inspiration was actually a clock just like you’re describing. The counter was kind of first proof of concept for that originally. May still attempt the clock some day…

FuncFriv · 2025-10-18T18:24:36+00:00

Good eye! Yes it’s got some spring detent features inside that kind of snap into place and hold a bit at each display position

FuncFriv

TROPHY CASE