Knob Rotation Clearance

Dough Castro commented on Discord regarding, the knobs, why they’re loose and if they’d get even looser:

“The switches aren’t going anywhere. The tolerances were a bit too big because on prototyping they were made too tight and we several issue of actuators feeling scratchy (nails on a chalkboard type) when rotating or pressing, and other issues. I decided to play it safe with the tolerance but maybe they could be tighten up. The actuators are reliable as hell, it’s just a matter of feel but yeah, it should feel as well as it’s designed and constructed.”

Yes. I understand about too tight will cause binding, etc…
The problem is the consistency. Some are 5, 10, 15, 30, and even 40 degrees. If you are manufacturing something. These discrepancies aren’t acceptable…
The right thing to do should be:
Right, 15 degrees is a sweet spot. Let’s make EVERY SINGLE KNOB 15 degrees.
That’s where my beef is… :slight_smile:

‘‘Now. Before you say: “Don’t compare a car with a quad cortex”. I will answer this:
You bought a super expensive product and you expect: “Precision, repeatability and consistency”
Precision and consistency are missing…’’

You are correct, but Quality (tight tolerances) comes with a cost, but no added value. - indeed a unit without defect is not of more value than one with defect since you’ll end up replacing the latter.
But it comes with a cost because it increases out of tolerance parts.

What we must ask ourselves is ‘‘does it make the unit defective, or work less well ?’’ if the answer is yes, then it must be looked upon, if not, then its because it’s an accepted tolerance design.

“What we must ask ourselves is ‘‘does it make the unit defective, or work less well ?’’ if the answer is yes, then it must be looked upon, if not, then its because it’s an accepted tolerance design.”

100%. I agree as long as the customers (not the manufacturer) have the final saying here.

What you’re forgetting is that the owner of the defective unit goes on forums and talks to his friends and dissuades others from buying a unit with this level of (perceived) oversight and QC (no pun intended) issues. A unit without defect is infinitely more valuable since the owner will sing its praises from the mountaintops and encourage others to buy it. Just my 2c.

That’s exactly the point.

NDSP would not sell 2 ‘‘levels’’ of units, one flawless, and one with defect at a lesser cost.
When you buy a unit, you expect it to be like the others, quality wise. This means that
nobody wants to buy or sell a unit that has quality issue.

This is why quality control is unfortunately not added value, it is a decrease in loss and comes at a price. Think of it as damage control

haha I think we’re looking at the same thing from two different angles. You see a decrease in loss by having good QC, whereas I see an increase in sales; both may be true. :stuck_out_tongue_winking_eye:

I wished it was the way you say it.
But I’ve in metrology process all my life, and the only thing I’ve heard from all the companies I’ve dealt with is this: You make money making a product, not measuring it.

If you go to the store and test all modelers, of course you wont buy one of them if it is broken, but still. you’d expect all of them to work as intended no matter their price. And you are correct in expecting that the pricier has more quality because again, quality is an added cost, not an added value.

A requirement of 100mm +/- 5mm is as good as 100mm +/- 0.050mm if both are measured at 100mm, yet the latter will probably be 40% more expensive. Yet is it better?

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