Anyone have a laser cutter and could cut me out a couple small (~30*14*10mm) pieces?

[Kram]

Seventy two hours!?!? That is cheap.

We never had space suits, but once a month they wanted a pee check that we hadnt been eating the cobalt.

 

[Agroshield]

...for the 3d sintered process that doesn't matter

It might be useful to research the stress and fatigue behaviour of sintered parts compared to ones made from solid.

The consequences of one of the teeth shearing off at the root might be high.

With some proper engineering thought, it is possible to put a large root radius on the teeth to minimise stress concentration. You have to engineer the part to suit the material from which it is made - designing to be made from solid will not necessarily transfer unproblematically to another manufacturing process.

To me, as suggested above, making them from a laminated stack of thinner pieces would be the way to go for production. Then they could be stamped out at about 1000 pieces per minute.

 

[Bki26]

I was curious so I quickly traced your drawing and made a 3d model 10mm thick and stuck it in JLCCNC for a quote. Surprisingly low indeed.

those aren't properly involute teeth profiles of course since I just did a more or less freehand trace but for the 3d sintered process that doesn't matter and for the machined one its just gives an idea. Shame they don't machine in steel.

I image you wont have to look too hard to find online EDM services too and it'd be a cinch for them to do that part.

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Yea it's £7 a part so gonna do that and hopefully tap a thread in some of them, it's not gear teeth just a random profile I created as it's designed as a rope grab

 

[Agroshield]

...hopefully tap a thread in some of them

Where did that come from?

Do you not think it would have been relevant to mention that at the beginning?

Any laser-cut item will have a heat affected zone, which will complicate tapping. Do some research on tapping a sintered part.

 

[Maker]

Agroshield makes a good point above, I assume (but have no experience and haven't Googled it) that a sintered part will fail suddenly with little to no elongation, where a solid metal part would stretch before it breaks and potentially give some warning before a catastrophic failure.

I don't like the sound of a brittle failure on a rope grab, which I assume is part of an auto-belay type device?

 

[Erie Fred]

Where did that come from?

Do you not think it would have been relevant to mention that at the beginning?

Any laser-cut item will have a heat affected zone, which will complicate tapping. Do some research on tapping a sintered part.

Some OP's on here treat it like an interrogation to get any info, having to cross examine the OP
to finally get to a conclusion.

Ask a stupid question get stupid answers.

OR

G.I.G.O.

 

[Agroshield]

I don't like the sound of a brittle failure on a rope grab...

To be fair, as the teeth are digging into a rope, the stress will be different to if they were acting as gear teeth.

The reason to raise these issues is so as not to waste people's time and money. If I had waited two weeks for my sintered part to come from China and then it disintegrated after I poked an M5 tap into it, I would cry, even if it was only $6.

If the item does require threads, in a prototype they could be provided in an alternative way, which would be inefficient for quantity production but would be OK for testing the fit and function of the part.

 

[Erie Fred]

Brings up good points ^^^
if production warrants, powered metal is an option.
FWIU die cost is not very high, as it's a simple cavity.

 

[Bki26]

Where did that come from?

Do you not think it would have been relevant to mention that at the beginning?

Any laser-cut item will have a heat affected zone, which will complicate tapping. Do some research on tapping a sintered part.

Different part I'm referring to but the toothed one isn't threaded