| Author |
Message |
Joerg
Guest
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 Posted:
Mon Dec 12, 2005 1:35 am Post subject:
Very cheap molded enclosures? |
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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 $2 (still too
high) they charge an arm and a leg for drilling and I need at least a
dozen holes for LED and stuff. Heck, often they even charge extra for a
battery holder so I wonder whether they anticipate that the usual design
will be a perpetuum mobile that doesn't need any power.
I my case I need a cheap 'snap together' enclosure that can accomodate
2-3 AA cells or AAA cells, has a dozen LED holes and maybe a small power
switch. The circuit board would then be adapted to whatever it needs to
be for that enclosure.
Regards, Joerg
http://www.analogconsultants.com
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Ken Smith
Guest
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| Posted:
Mon Dec 12, 2005 1:35 am Post subject:
Re: Very cheap molded enclosures? |
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In article <jl0nf.30391$dO2.24789@newssvr29.news.prodigy.net>,
Joerg <notthisjoergsch@removethispacbell.net> wrote:
[...]
| Quote: | high) they charge an arm and a leg for drilling and I need at least a
dozen holes for LED and stuff.
|
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.
--
--
kensmith@rahul.net forging knowledge |
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Guest
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| Posted:
Mon Dec 12, 2005 1:35 am Post subject:
Re: Very cheap molded enclosures? |
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Joerg wrote:
| Quote: | Hello Ken,
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.
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.
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.
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.
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.
I could make the PCB anything it needs to be and the electronics are
quite simple. Space isn't an issue.
Regards, Joerg
http://www.analogconsultants.com
|
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
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Joerg
Guest
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| Posted:
Mon Dec 12, 2005 1:35 am Post subject:
Re: Very cheap molded enclosures? |
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|
Hello Ken,
| Quote: |
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.
|
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.
| Quote: | 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.
|
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.
| Quote: |
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.
|
I could make the PCB anything it needs to be and the electronics are
quite simple. Space isn't an issue.
Regards, Joerg
http://www.analogconsultants.com |
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Joerg
Guest
|
| Posted:
Mon Dec 12, 2005 1:35 am Post subject:
Re: Very cheap molded enclosures? |
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|
Hello NT,
| Quote: | 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.
|
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
http://www.analogconsultants.com |
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Ken Smith
Guest
|
| Posted:
Mon Dec 12, 2005 1:48 am Post subject:
Re: Very cheap molded enclosures? |
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|
In article <ZB2nf.39573$6e1.24572@newssvr14.news.prodigy.com>,
Joerg <notthisjoergsch@removethispacbell.net> wrote:
[...]
| Quote: | A linear array of LED would make viewing from a distance tricky and
would require the label font to be very small. These arrays also cost
quite a bit.
|
How about a semi-clear window with a row of normal LEDs behind it? This
may cost less than a row of holes. Perhaps the box could be made out of
something clear.
| Quote: | So far it is around 15c/hole and that's too much. But the real problem
is the box itself. With a battery holding facility of a somewhat decent
quality that alone becomes quite expensive.
|
How about a, solder down 9V holder or the like and requiring that the box
be opened to change the battery?
| Quote: | I could make the PCB anything it needs to be and the electronics are
quite simple. Space isn't an issue.
|
How about really bright LEDs and no holes in the PCB for them? Since you
want largish spacing, the spreading of the light may not be a bad thing.
--
--
kensmith@rahul.net forging knowledge |
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Ken Smith
Guest
|
| Posted:
Mon Dec 12, 2005 1:49 am Post subject:
Re: Very cheap molded enclosures? |
|
|
In article <Jl4nf.30430$dO2.26303@newssvr29.news.prodigy.net>,
Joerg <notthisjoergsch@removethispacbell.net> wrote:
[...]
| Quote: | 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.
|
Make your sticky label cover all the sins?
--
--
kensmith@rahul.net forging knowledge |
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Spehro Pefhany
Guest
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| Posted:
Mon Dec 12, 2005 7:53 am Post subject:
Re: Very cheap molded enclosures? |
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On Mon, 12 Dec 2005 01:27:05 GMT, the renowned Joerg
<notthisjoergsch@removethispacbell.net> wrote:
| Quote: | 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.
|
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
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com |
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Guest
|
| Posted:
Mon Dec 12, 2005 9:35 am Post subject:
Re: Very cheap molded enclosures? |
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Joerg wrote:
| Quote: | Hello NT,
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.
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.
|
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.
| Quote: | 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.
|
most diy project boxes are like that. No idea whether that kind of
finish suits your app tho.
| Quote: | 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
http://www.analogconsultants.com
|
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 |
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Tim Wescott
Guest
|
| Posted:
Mon Dec 12, 2005 5:35 pm Post subject:
Re: Very cheap molded enclosures? |
|
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Joerg wrote:
| Quote: | 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.
|
I like your posts, Joerg. "Low quantities" = "10k/year". I've never
worked on anything with production higher than 100ea per year.
| Quote: |
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?
|
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.
| Quote: | Or a company that would do the whole production
based on one of their standard enclosures?
|
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.
| Quote: |
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.
|
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).
| Quote: |
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
http://www.analogconsultants.com
|
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).
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com |
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