>>IIRC you should apply for the patent before you release the product >>(or even just keep it secret) or you may lose your rights. This >>presumes patenting the thing is a good idea in the first place - which >>is unlikely unless you have deep pockets.
>>>IIRC you should apply for the patent before you release the product >>>(or even just keep it secret) or you may lose your rights. This >>>presumes patenting the thing is a good idea in the first place - which >>>is unlikely unless you have deep pockets.
On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
> On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
> <jaleg...@sympatico.ca> wrote: > >IIRC you should apply for the patent before you release the product > >(or even just keep it secret) or you may lose your rights. This > >presumes patenting the thing is a good idea in the first place - which > >is unlikely unless you have deep pockets.
> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
> > <jaleg...@sympatico.ca> wrote: > > >IIRC you should apply for the patent before you release the product > > >(or even just keep it secret) or you may lose your rights. This > > >presumes patenting the thing is a good idea in the first place - which > > >is unlikely unless you have deep pockets.
> > It's not fair if I lose my patentability rights when I'd like to > > release 200 units for ~field testing~ :) > > to tweek and finalize the design.
> The wikipedia article mentions that you can protect your rights by > obtaining non-disclosure agreements.
We spray paint our PCB's black, for a sealant and thermodynamic (black-body) radiation, it also makes a direct copy difficult. Ken
<dynam...@vianet.on.ca> wrote: >On Nov 4, 7:46 pm, "J.A. Legris" <jaleg...@sympatico.ca> wrote: >> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
>> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
>> > <jaleg...@sympatico.ca> wrote: >> > >IIRC you should apply for the patent before you release the product >> > >(or even just keep it secret) or you may lose your rights. This >> > >presumes patenting the thing is a good idea in the first place - which >> > >is unlikely unless you have deep pockets.
>> > It's not fair if I lose my patentability rights when I'd like to >> > release 200 units for ~field testing~ :) >> > to tweek and finalize the design.
>> The wikipedia article mentions that you can protect your rights by >> obtaining non-disclosure agreements.
>We spray paint our PCB's black, for a sealant and thermodynamic >(black-body) radiation, it also makes a direct copy difficult.
Not sure why you think black paint increases thermal radiation, but it's certainly not going to stop anyone from copying the design. It may slow them down by about five minutes. Maybe.
> On Thu, 5 Nov 2009 15:08:58 -0800 (PST), "Ken S. Tucker"
> <dynam...@vianet.on.ca> wrote: > >On Nov 4, 7:46 pm, "J.A. Legris" <jaleg...@sympatico.ca> wrote: > >> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
> >> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
> >> > <jaleg...@sympatico.ca> wrote: > >> > >IIRC you should apply for the patent before you release the product > >> > >(or even just keep it secret) or you may lose your rights. This > >> > >presumes patenting the thing is a good idea in the first place - which > >> > >is unlikely unless you have deep pockets.
> >> > It's not fair if I lose my patentability rights when I'd like to > >> > release 200 units for ~field testing~ :) > >> > to tweek and finalize the design.
> >> The wikipedia article mentions that you can protect your rights by > >> obtaining non-disclosure agreements.
> >We spray paint our PCB's black, for a sealant and thermodynamic > >(black-body) radiation, it also makes a direct copy difficult.
> Not sure why you think black paint increases thermal radiation, but > it's certainly not going to stop anyone from copying the design. It > may slow them down by about five minutes. Maybe.
It also makes the board likely to fail. The solvent in spray paint is hard on parts. As a result the product will get a reputation for being crap. Since nobody wants to make a copy of a crap product, people will be less likely to copy it.
On Mon, 02 Nov 2009 13:16:28 -0800, D from BC <myrealaddr...@comic.com> wrote:
:I'd like to pot my smt pcb with the nastiest sh*t possible to make it :hell for copy cats.. : :So far I've found: : :http://www.mgchemicals.com/products/832ht.html :'Extremely difficult to remove - grants incredible technology :protection ' : :Besides epoxy.. Are there alternatives? : :ex: Very very hot melt? Low melting point glass? : :D from BC :Amateur smps designer :British Columbia, Canada :Posted to sci.electronics.design
One thing you need to remember.. if there are any heat generating components on the board, encapsulation in a hard compound may cause subsequent fracturing of components or solder joints because they can't expand and contract. This may not be such a problem with smt but it has caused problems with thru-hole components on some pcb's I have repaired.
Since Araldite 2014 (3 types btw) http://www.kirkside.com.au/Uploads/Images/2014.pdf is a bonding adhesive it may cure to be extremely hard and may not allow expansion/contraction of components. If this is likely to be a problem I would recommend a thin coating of pourable white silicone rubber (or similar) over the heat generating components before applying the Araldite 2014.
Ross Herbert wrote: > One thing you need to remember.. if there are any heat generating components on > the board, encapsulation in a hard compound may cause subsequent fracturing of > components or solder joints because they can't expand and contract.
I know an engineer who spent many years mixing different compounds and fillers trying to create solid substance with minimal expansion or contraction while it is cured, and which will not rip the components off the PCB because of thermal effects. This is no simple problem.
On Thu, 05 Nov 2009 22:37:53 -0600, Vladimir Vassilevsky <nos...@nowhere.com> wrote:
: :
:Ross Herbert wrote:
: : :> One thing you need to remember.. if there are any heat generating components on :> the board, encapsulation in a hard compound may cause subsequent fracturing of :> components or solder joints because they can't expand and contract. : :I know an engineer who spent many years mixing different compounds and :fillers trying to create solid substance with minimal expansion or :contraction while it is cured, and which will not rip the components off :the PCB because of thermal effects. This is no simple problem. : : :Vladimir Vassilevsky :DSP and Mixed Signal Design Consultant :http://www.abvolt.com
I entirely agree with you Vladimir... However, depending upon the amount of heat generated or the degree of expansion/contraction involved it may not be as extreme as your engineer friend encountered.
The very first instance of this type of problem which I encountered was in electronic ignition systems from Johnson outboard motors back in the 70's. After dissolving the epoxy encapsulant (that took weeks using an expensive chemical solvent supposed to be specific to this purpose) it was discovered that several soldered joints had failed and pcb pads had actually been lifted from the board by the expansion of vertically mounted resistors in particular. Incidentally, the solvent removed the coatings on resistors and other capacitors so determining values was impossible in many case. I never intended to repair the units but I was interested in the failure mechanism of these units. I communicated my findings to Johnson at the time but I never received any acknowledgement.
>On Nov 5, 4:19 pm, krw <k...@att.bizzzzzzzzzzz> wrote: >> On Thu, 5 Nov 2009 15:08:58 -0800 (PST), "Ken S. Tucker"
>> <dynam...@vianet.on.ca> wrote: >> >On Nov 4, 7:46 pm, "J.A. Legris" <jaleg...@sympatico.ca> wrote: >> >> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
>> >> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
>> >> > <jaleg...@sympatico.ca> wrote: >> >> > >IIRC you should apply for the patent before you release the product >> >> > >(or even just keep it secret) or you may lose your rights. This >> >> > >presumes patenting the thing is a good idea in the first place - which >> >> > >is unlikely unless you have deep pockets.
>> >> > It's not fair if I lose my patentability rights when I'd like to >> >> > release 200 units for ~field testing~ :) >> >> > to tweek and finalize the design.
>> >> The wikipedia article mentions that you can protect your rights by >> >> obtaining non-disclosure agreements.
>> >We spray paint our PCB's black, for a sealant and thermodynamic >> >(black-body) radiation, it also makes a direct copy difficult.
>> Not sure why you think black paint increases thermal radiation, but >> it's certainly not going to stop anyone from copying the design. It >> may slow them down by about five minutes. Maybe.
>It also makes the board likely to fail. The solvent in spray paint is >hard on parts. As a result the product will get a reputation for >being crap. Since nobody wants to make a copy of a crap product, >people will be less likely to copy it.
>> One thing you need to remember.. if there are any heat generating components on >> the board, encapsulation in a hard compound may cause subsequent fracturing of >> components or solder joints because they can't expand and contract.
>I know an engineer who spent many years mixing different compounds and >fillers trying to create solid substance with minimal expansion or >contraction while it is cured, and which will not rip the components off >the PCB because of thermal effects. This is no simple problem.
>Vladimir Vassilevsky >DSP and Mixed Signal Design Consultant >http://www.abvolt.com
Quite simple. Conformal coat the PCB prior to potting.
Still getting breakage? Conformal coat... twice. Make a blanket.
On Thu, 05 Nov 2009 21:46:50 -0800, D from BC <myrealaddr...@comic.com> wrote:
You did not write it, but I am lazy tonight...
>>It also makes the board likely to fail. The solvent in spray paint is >>hard on parts.
So much horseshit.
Transformer encapsulant (varnish) from a spray can. Dolph's. brand, to be specific.
We coated THOUSANDS of HIGH VOLTAGE power supplies with a volatile vehicle spray can applied coating, and baked it dry, after a vacuuming of the board.
We have even done vacuum impregnation of the PCB which draws the coating up inside the unmasked PCB media.
And we used a volatile solvent type thinner to cut the main gallon with.
On Nov 5, 9:46 pm, D from BC <myrealaddr...@comic.com> wrote:
> On Thu, 5 Nov 2009 18:42:45 -0800 (PST), MooseFET <kensm...@rahul.net> [....]
> >It also makes the board likely to fail. The solvent in spray paint is > >hard on parts. As a result the product will get a reputation for > >being crap. Since nobody wants to make a copy of a crap product, > >people will be less likely to copy it.
> Ha.. Copy protection by deliberate low quality.
This is why cars made today don't look like the Pinto.
A company in Redmond Washington was trying the idea on software. I wonder what ever happened to them.
On Nov 5, 8:37 pm, Vladimir Vassilevsky <nos...@nowhere.com> wrote:
> Ross Herbert wrote: > > One thing you need to remember.. if there are any heat generating components on > > the board, encapsulation in a hard compound may cause subsequent fracturing of > > components or solder joints because they can't expand and contract.
> I know an engineer who spent many years mixing different compounds and > fillers trying to create solid substance with minimal expansion or > contraction while it is cured, and which will not rip the components off > the PCB because of thermal effects. This is no simple problem.
You also have to match the thermal expansion. This makes it extra hard because you need to balance two things.
I went down the potting road in the past and discovered that an aluminum housing was cheaper to do in production.
> On Nov 5, 4:19 pm, krw <k...@att.bizzzzzzzzzzz> wrote:
> > On Thu, 5 Nov 2009 15:08:58 -0800 (PST), "Ken S. Tucker"
> > <dynam...@vianet.on.ca> wrote: > > >On Nov 4, 7:46 pm, "J.A. Legris" <jaleg...@sympatico.ca> wrote: > > >> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
> > >> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
> > >> > <jaleg...@sympatico.ca> wrote: > > >> > >IIRC you should apply for the patent before you release the product > > >> > >(or even just keep it secret) or you may lose your rights. This > > >> > >presumes patenting the thing is a good idea in the first place - which > > >> > >is unlikely unless you have deep pockets.
> > >> > It's not fair if I lose my patentability rights when I'd like to > > >> > release 200 units for ~field testing~ :) > > >> > to tweek and finalize the design.
> > >> The wikipedia article mentions that you can protect your rights by > > >> obtaining non-disclosure agreements.
> > >We spray paint our PCB's black, for a sealant and thermodynamic > > >(black-body) radiation, it also makes a direct copy difficult.
> > Not sure why you think black paint increases thermal radiation, but > > it's certainly not going to stop anyone from copying the design. It > > may slow them down by about five minutes. Maybe.
> It also makes the board likely to fail. The solvent in spray paint is > hard on parts. As a result the product will get a reputation for > being crap. Since nobody wants to make a copy of a crap product, > people will be less likely to copy it.
That's funny. I'll write a memo to QC and production right now! "MooseFET" approves your spray paint. Ken
On Fri, 6 Nov 2009 06:31:34 -0800 (PST), MooseFET <kensm...@rahul.net> wrote:
>On Nov 5, 9:46 pm, D from BC <myrealaddr...@comic.com> wrote: >> On Thu, 5 Nov 2009 18:42:45 -0800 (PST), MooseFET <kensm...@rahul.net> >[....]
>> >It also makes the board likely to fail. The solvent in spray paint is >> >hard on parts. As a result the product will get a reputation for >> >being crap. Since nobody wants to make a copy of a crap product, >> >people will be less likely to copy it.
>> Ha.. Copy protection by deliberate low quality.
>This is why cars made today don't look like the Pinto.
>A company in Redmond Washington was trying the idea on software. I >wonder what ever happened to them.
On Nov 6, 8:14 am, "Ken S. Tucker" <dynam...@vianet.on.ca> wrote:
> On Nov 5, 6:42 pm, MooseFET <kensm...@rahul.net> wrote: [....]
> > It also makes the board likely to fail. The solvent in spray paint is > > hard on parts. As a result the product will get a reputation for > > being crap. Since nobody wants to make a copy of a crap product, > > people will be less likely to copy it.
> That's funny. I'll write a memo to QC and production right now! > "MooseFET" approves your spray paint. > Ken
Quality control is like crowd control. You have riot control to make sure crowds don't get out of hand and you have quality control to make sure quality doesn't get out of hand. This way, people won't want to copy your products.
>On Nov 3, 1:15 am, Archimedes' Lever <OneBigLe...@InfiniteSeries.Org> >wrote: >> On Mon, 2 Nov 2009 22:03:41 -0800 (PST), Greegor <greego...@gmail.com> >> wrote:
>> >How do you like getting products made that way?
>> Unless YOU QUOTE who you are responding to, nobody will know who or >> what the fuck you are talking about.
>> Not everyone reads or looks at there news the same way.
>> Relying on threaded views is retarded.
>> QUOTE what you are referring to. D'oh!
>Read the subject title, Archy!
>SUBJECT: "PCB Encapsulants to Annoy Copy Pirates" >G > How do you like getting products made that way?
Folks respond to the BODY of a post, not the fucking topic title. Those that do have their reward, and are pretty fucking stupid as well.
Also, why would some fucking total retard snip the entire body containing the details of what the person wanted to know, just to make a snide fucking peanut gallery comment?
Oh... wait... That was a Retard Gallery comment. It's all clear now.
<dynam...@vianet.on.ca> wrote: >On Nov 4, 7:46 pm, "J.A. Legris" <jaleg...@sympatico.ca> wrote: >> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
>> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
>> > <jaleg...@sympatico.ca> wrote: >> > >IIRC you should apply for the patent before you release the product >> > >(or even just keep it secret) or you may lose your rights. This >> > >presumes patenting the thing is a good idea in the first place - which >> > >is unlikely unless you have deep pockets.
>> > It's not fair if I lose my patentability rights when I'd like to >> > release 200 units for ~field testing~ :) >> > to tweek and finalize the design.
>> The wikipedia article mentions that you can protect your rights by >> obtaining non-disclosure agreements.
>We spray paint our PCB's black, for a sealant and thermodynamic >(black-body) radiation, it also makes a direct copy difficult. >Ken
You should get a good, thermally conductive epoxy paint to seal it up in, and *then* coat it with real black body paint, which contains enough Carbon to worry me as a direct spray on, but would be fine as an overcoat on the thermal epoxy. Then, you have a conductively cooled device from the source through the epoxy, and a radiant cooled device from the "heat sink" POV. That paint is pretty good at "emitting" the energy 'behind it'.
> On Thu, 5 Nov 2009 15:08:58 -0800 (PST), "Ken S. Tucker"
> <dynam...@vianet.on.ca> wrote: > >On Nov 4, 7:46 pm, "J.A. Legris" <jaleg...@sympatico.ca> wrote: > >> On Nov 4, 12:33 pm, D from BC <myrealaddr...@comic.com> wrote:
> >> > On Wed, 4 Nov 2009 09:10:48 -0800 (PST), "J.A. Legris"
> >> > <jaleg...@sympatico.ca> wrote: > >> > >IIRC you should apply for the patent before you release the product > >> > >(or even just keep it secret) or you may lose your rights. This > >> > >presumes patenting the thing is a good idea in the first place - which > >> > >is unlikely unless you have deep pockets.
> >> > It's not fair if I lose my patentability rights when I'd like to > >> > release 200 units for ~field testing~ :) > >> > to tweek and finalize the design.
> >> The wikipedia article mentions that you can protect your rights by > >> obtaining non-disclosure agreements.
> >We spray paint our PCB's black, for a sealant and thermodynamic > >(black-body) radiation, it also makes a direct copy difficult. > >Ken
> You should get a good, thermally conductive epoxy paint to seal it up > in, and *then* coat it with real black body paint, which contains enough > Carbon to worry me as a direct spray on, but would be fine as an overcoat > on the thermal epoxy. Then, you have a conductively cooled device from > the source through the epoxy, and a radiant cooled device from the "heat > sink" POV. That paint is pretty good at "emitting" the energy 'behind > it'.
Your thinking is appreciated. Our standard was set using a 10M ohm resistor, measured accurately then spraying it and the leads, and then measure the diff, you know. Following that, we choose to protect PCB's that way to start. Of course a good circuit design is where it begins. Ken
:> :> :>> One thing you need to remember.. if there are any heat generating components on :>> the board, encapsulation in a hard compound may cause subsequent fracturing of :>> components or solder joints because they can't expand and contract. :> :>I know an engineer who spent many years mixing different compounds and :>fillers trying to create solid substance with minimal expansion or :>contraction while it is cured, and which will not rip the components off :>the PCB because of thermal effects. This is no simple problem. :> :> :>Vladimir Vassilevsky :>DSP and Mixed Signal Design Consultant :>http://www.abvolt.com : : : Quite simple. Conformal coat the PCB prior to potting. : : Still getting breakage? Conformal coat... twice. Make a blanket.
It is far simpler and more effective to simply dip the whole board in pourable silicone rubber prior to encapsulation with the hard epoxy. That will leave plenty of room for expansion.
>On Fri, 06 Nov 2009 01:14:03 -0800, Archimedes' Lever ><OneBigLe...@InfiniteSeries.Org> wrote:
>:On Thu, 05 Nov 2009 22:37:53 -0600, Vladimir Vassilevsky >:<nos...@nowhere.com> wrote: >: >:> >:> >:>Ross Herbert wrote: >:> >:> >:>> One thing you need to remember.. if there are any heat generating components >on >:>> the board, encapsulation in a hard compound may cause subsequent fracturing >of >:>> components or solder joints because they can't expand and contract. >:> >:>I know an engineer who spent many years mixing different compounds and >:>fillers trying to create solid substance with minimal expansion or >:>contraction while it is cured, and which will not rip the components off >:>the PCB because of thermal effects. This is no simple problem. >:> >:> >:>Vladimir Vassilevsky >:>DSP and Mixed Signal Design Consultant >:>http://www.abvolt.com >: >: >: Quite simple. Conformal coat the PCB prior to potting. >: >: Still getting breakage? Conformal coat... twice. Make a blanket.
>It is far simpler and more effective to simply dip the whole board in pourable >silicone rubber prior to encapsulation with the hard epoxy. That will leave >plenty of room for expansion.
Conformal coating can be spray applied or used as a dip, and the coating thickness can be altered by simply buying the right coating to achieve the right thickness desired in a single dip.
Make it too thick, and the security features go away.
> :On Thu, 05 Nov 2009 22:37:53 -0600, Vladimir Vassilevsky:<nos...@nowhere.com> wrote:
> : > :> > :>:>Ross Herbert wrote:
> :> > :> > :>> One thing you need to remember.. if there are any heat generating components > on > :>> the board, encapsulation in a hard compound may cause subsequent fracturing > of > :>> components or solder joints because they can't expand and contract. > :> > :>I know an engineer who spent many years mixing different compounds and > :>fillers trying to create solid substance with minimal expansion or > :>contraction while it is cured, and which will not rip the components off > :>the PCB because of thermal effects. This is no simple problem. > :> > :> > :>Vladimir Vassilevsky > :>DSP and Mixed Signal Design Consultant > :>http://www.abvolt.com > : > : > : Quite simple. Conformal coat the PCB prior to potting. > : > : Still getting breakage? Conformal coat... twice. Make a blanket.
> It is far simpler and more effective to simply dip the whole board in pourable > silicone rubber prior to encapsulation with the hard epoxy. That will leave > plenty of room for expansion.
Well ok, as long as the silly-cone has the appropriate thermal conduction. I'd order a thermistor measure on the x-PCB to verify temp remains happy on power components, if it has any. Ken
<dynam...@vianet.on.ca> wrote: >On Nov 7, 12:50 am, Ross Herbert <rherb...@bigpond.net.au> wrote: >> On Fri, 06 Nov 2009 01:14:03 -0800, Archimedes' Lever
>> :On Thu, 05 Nov 2009 22:37:53 -0600, Vladimir Vassilevsky:<nos...@nowhere.com> wrote:
>> : >> :> >> :>:>Ross Herbert wrote:
>> :> >> :> >> :>> One thing you need to remember.. if there are any heat generating components >> on >> :>> the board, encapsulation in a hard compound may cause subsequent fracturing >> of >> :>> components or solder joints because they can't expand and contract. >> :> >> :>I know an engineer who spent many years mixing different compounds and >> :>fillers trying to create solid substance with minimal expansion or >> :>contraction while it is cured, and which will not rip the components off >> :>the PCB because of thermal effects. This is no simple problem. >> :> >> :> >> :>Vladimir Vassilevsky >> :>DSP and Mixed Signal Design Consultant >> :>http://www.abvolt.com >> : >> : >> : Quite simple. Conformal coat the PCB prior to potting. >> : >> : Still getting breakage? Conformal coat... twice. Make a blanket.
>> It is far simpler and more effective to simply dip the whole board in pourable >> silicone rubber prior to encapsulation with the hard epoxy. That will leave >> plenty of room for expansion.
>Well ok, as long as the silly-cone has the appropriate thermal >conduction. I'd order a thermistor measure on the x-PCB to >verify temp remains happy on power components, if it has any. >Ken
You find that out when you beat up ten finished assembly candidates till they fail. Then find out where they failed and why.
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