Very cheap molded enclosures?

I've never tried this, but will pull it outta my ass cos you look fairly stuck. What if you use the pcb as one of the 6 box sides: discard the original lid and use a suitably sized drilled pcb, with all controls and LEDs mounted in holes in it. All the tronics would need to be sm on the other side. Unlikely, but who knows, with no more info on your product.

NT

Reply to
meow2222
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I know from my experience being approached that it doesn't seem so attractive to take the fruits of tens of thousands of dollars in tooling and sell them on the street. What if they helped a competitor get going? It's a *welcome* barrier to entry once the money is sunk.

Are the quantity requirements firm (min 10k-15k), or this something that you have to build and see if the market comes?

Best regards, Spehro Pefhany

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Reply to
Spehro Pefhany

Hello Newsgroup,

Again I came upon the usual hardcore enclosure challenge: Initial quantities will be low, 10k to 20k/year, but the whole device would be doomed if production cost would be greater than $7-8. Sales just wouldn't happen.

Question: Is there a company that offers "shuttle runs" for enclosures? Just as they are offered for chips where you 'ride along' on a corner of someone else's wafer? Or a company that would do the whole production based on one of their standard enclosures?

I checked with the usual plastic enclosure makers and it just won't fly. At that qty a regular run-of-the-mills enclosure of 1.5" by 3" would cost well over $5. While the raw case would drop to around $2 (still too high) they charge an arm and a leg for drilling and I need at least a dozen holes for LED and stuff. Heck, often they even charge extra for a battery holder so I wonder whether they anticipate that the usual design will be a perpetuum mobile that doesn't need any power.

I my case I need a cheap 'snap together' enclosure that can accomodate

2-3 AA cells or AAA cells, has a dozen LED holes and maybe a small power switch. The circuit board would then be adapted to whatever it needs to be for that enclosure.

Regards, Joerg

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Reply to
Joerg

In article , Joerg wrote: [...]

Are you sure you really need that many holes? This may be the place to get clever to save the design. Multicolor LEDs and combining controls may help.

I've had letting a machine shop do it come out cheaper than having a molding company do it. If you can start with something they can grip very easily, a machine shop can make holes very quickly. My prices are way above yours but its worth asking.

If you had a box with a big square opening, could you make a PCB with holes in it to fit? If your electronics is simple enough, it could be on the hidden side.

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kensmith@rahul.net   forging knowledge
Reply to
Ken Smith

Hello Ken,

The box would have to display the presence of about a dozen events and this can't really be combined. Several events can happen in parallel. There needs to be a brief notion next to each LED which could be done with a self-adhesive (peel and stick) overlay next to the row of LEDs. Ideally in a large font of at least 20 point.

A linear array of LED would make viewing from a distance tricky and would require the label font to be very small. These arrays also cost quite a bit.

So far it is around 15c/hole and that's too much. But the real problem is the box itself. With a battery holding facility of a somewhat decent quality that alone becomes quite expensive.

I could make the PCB anything it needs to be and the electronics are quite simple. Space isn't an issue.

Regards, Joerg

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Reply to
Joerg

spray it, or make it all coppered and etchmasked with only fine spacing between ground and other tracks, or cover it with yout front label. Or be daring and incorporate geometric designs in the ground plane to make the other tracks not stand out.

most diy project boxes are like that. No idea whether that kind of finish suits your app tho.

I reckon Kens idea is the smartest, no holes and ultrabrights. You could use the copper ground plane on the outer side to make optical holes if you want, or patterns etc - or even possibly a lit up letter, words or symbol.

NT

Reply to
meow2222

Hello NT,

It is a pretty simple product. Can't tell much about it but basically it catches roughly a dozen events which need to be signaled via a row of LEDs. The PCB will have to be double sided for cost reasons and one side is mostly ground (because of a uC). Not all of that side can be ground so it would look a little utilitarian if it would show.

I thought about having another PCB produced that just contains the holes because it seems that machine drilling enclosure parts costs a lot more per hole than the same hole on a PCB. However, then you need a box into which that PCB can be mounted without exposing the rough FR4 edges.

Another method is to try to find a product from a very different market but with an enclosure that would work and then approach that manufacturer. I will try this since I found one with such an enclosure but in the past I have seen little success with such business propositions. Large companies often just don't have a mechanism in place to handle such deals. It would be really easy revenue for them.

Regards, Joerg

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Reply to
Joerg

In article , Joerg wrote: [...]

How about a semi-clear window with a row of normal LEDs behind it? This may cost less than a row of holes. Perhaps the box could be made out of something clear.

How about a, solder down 9V holder or the like and requiring that the box be opened to change the battery?

How about really bright LEDs and no holes in the PCB for them? Since you want largish spacing, the spreading of the light may not be a bad thing.

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kensmith@rahul.net   forging knowledge
Reply to
Ken Smith

In article , Joerg wrote: [...]

Make your sticky label cover all the sins?

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Reply to
Ken Smith

I like your posts, Joerg. "Low quantities" = "10k/year". I've never worked on anything with production higher than 100ea per year.

The difference is that if you want the enclosure to be really cheap per piece you need to have the holes, and all other features, molded in. Drilling them after the fact will simply cost more.

I liked the suggestion to buy standard enclosures but have your own machine shop do the drilling. This may not save you anything after all, but it shouldn't be discounted.

If you place your LEDs in one or two rows you may be able to get away with one or two slots, which may be less than a bunch of holes. This may save some $$ if you have the work done at a stateside machine shop.

Most of those enclosures go into products that are well under 10k/year

-- and I think you've found out why.

I see a lot of stuff that I would estimate to be in the 1k/year (EPROM programmers, cheap frequency counters for ham radio, etc.) done in bent-up sheet metal. This doesn't accommodate your battery, but it seems to be a sweet spot (and rugged, too).

Have you investigated going straight to Taiwan? How about having a custom enclosure made (possibly in Taiwan)? It seems that for 10k/year you can afford to have some tooling made. I see stuff in what appears to be ready-made plastic cases that don't come from any of the usual suspects that I see in catalogs; I suspect there's a thriving industry for this over there if you can figure out how to tap into it.

If you go to the far east you don't even really need drawings. If you have a case all drilled and ready to go you can send it out as your "drawing" -- but you'll get an exact copy which may upset your local case manufacturer.

Years ago one of the suppliers in the street rod industry, who was known for sending parts of old Fords to Taiwan to be duplicated cheaply, came out with a cowl vent hinge for '32 Fords. Interestingly enough, instead of being a copy of a genuine Ford article -- two stamped steel pieces that were spot welded together -- it was a few thick sheet piece that was were bent on a jig, then wire welded with pieces of pipe for pivots

-- just like the ones my Dad's company had been making for years.

We took one of ours to them at a show, along with a real one. They confessed that they'd taken a rusty old one out of a clapped-out street rod and sent it off; it never occurred to them that they were making a repo of a repo.

We all had a good laugh (and they changed to a more genuine design).

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Reply to
Tim Wescott

Hello Spehro,

Doesn't have to be that way. We could enter into a contract making it very clear that it's going into a totally different market. Actually, we'd be more than willing to let them take over production for the whole thing once the sales volume matures. That should be a win-win situation, allowing them to crank a windfall out of their current mold design plus pocketing some margin for producing the units.

It's the usual, build and see. Initially it would be best to just buy the enclosure parts from them sans screen print. Then, when it does take off, move mass production to that company if they'd be interested.

Regards, Joerg

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Reply to
Joerg

Hello Ken,

I thought about clear boxes but those aren't very cheap.

No 9V blocks, they are a pain. Ripped off snap contacts and all that, it would create too many 'warranty' returns. Having to open the box wouldn't be an issue though. I think people have gotten used to that since this is what you have to do to change the batteries on many outdoor remote temperature sensors. My non-EE wife has no problems doing that.

Super brights blow the budget and would slurp up batteries too fast. Spread would be a problem but that could be mitigated by sliding tubing pieces over them. Drip irrigation tube snippets or the like.

Regards, Joerg

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Joerg

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A real problem with small offshore quantities at low prices is that the suppliers you really want to deal with really don't want your business, and they ones who really do want your business are the ones you really do not want to deal with. Really.

Best regards, Spehro Pefhany

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"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
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Reply to
Spehro Pefhany

Hello Tim,

Mostly I also work on lower volume stuff. But I actually enjoy those cut-throat price-driven high volume designs. 10k is low, a molded solution usually requires several times that.

On molded parts we always had everything molded in. No machine shop work whatsoever. But these were things that ran in larger quantities, often disposables.

I don't discount that but the prices I saw in the US are way too high. Have to shop around some more.

Slots often cost a lot more than drilled holes. The other downside is that if you use the regular round through-hole LEDs for cost reasons the gaps would allow dirt to lodge there. While the circuit can be made dirt-tolerant it would look icky after a while. Especially when people use the device while eating one of those Carl's Jr burgers.

Yes, and that's why I don't understand the darth of enclosures that already have holes in them. I mean, other than motes and repeaters there aren't many designs that don't need signaling or user interaction.

I don't have much in terms of good leads over there. But I am working on it. China might be another option. The ideal situation would be a company that can take care of the enclosure and then produce the whole unit as well.

Cool, IIRC that is also done with airplane parts for the really old freighters and prop passenger planes. There are a lot of DC3 still in regular service and somewhere they must get their parts from. Those airlines don't look like they could buy genuine spare parts all the time.

Regards, Joerg

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Reply to
Joerg

In the UK at least, there is an intermediate 'form' of injection moulding available. With this, the dies are made of much lower quality material, with a life expectancy of only about 2K+ pieces. They are made using a fairly simple CNC process, and the tooling costs are perhaps 1/100th that of a normal injection moulding process. For orders smaller than this, there are companies dong CNC folding processes, where the main box is formed from sheets of ABS, CNC milled, then folded and cut glued. They also have systems to add rails and supports. These processes cover quantities from about 2 off, up to perhaps 4K off, with proper injection moulding, combined with bonding for things like clear inserts, becoming the more economic process for larger numbers. I suspect you will find that similar setups exist in the States, but finding the company is the problem..

Best Wishes

Reply to
Roger Hamlett

Hello NT,

Ultrabrights are expensive and use too much battery juice. "See-through" FR4 would be really cool but unfortunately it's pretty milky.

Regards, Joerg

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Reply to
Joerg

"Joerg" schreef in bericht news:jl0nf.30391$ snipped-for-privacy@newssvr29.news.prodigy.net...

I've seen these LAN cable testers, with a row of leds. Something like this:

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Or perhaps this:

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Or search for 5840131551 on Ebay.

Get one of each and see which fits best. Then find a seller on

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and buy 10.000 for a buck a piece.

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Thanks, Frank.
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Reply to
Frank Bemelman

Hello Frank,

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This one looks nice, except that it has that dreaded 9V battery.

Well, you can't get the whole unit there for that price ;-)

But I am browsing around already to look at some big contract manufacturers. Preferably one that has a contact office in the US.

Regards, Joerg

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Reply to
Joerg

Hello Roger,

We have those in the US as well. However, whenever we looked into that in the past the cost savings weren't nearly that large and we ended up taking the plunge into the cold water, going diectly to classical injection molding. But when a client or project is VC financed they may not let you take that plunge.

That is rather expensive in the US. I don't see any way to keep enclosure costs under $4 that way. Well, maybe in Asia.

Regards, Joerg

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Reply to
Joerg

In article , Joerg wrote: [...]

Can you get away with 0.015" thick?

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kensmith@rahul.net   forging knowledge
Reply to
Ken Smith

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