I have use a similar but opposite system myself. I have been playing with under water ROVs for some time now and part of that requires video cameras for which I typically use the 12V, composite video, board camera modules. For mine I mounted the camera horizontally, mounted a mirror at a 45 degree angle in front of it then clamped it below the table of a HF bench top drill press. Took a few tries to get the camera centered under the center hole and I put some tape to mark the center point on the old TV I used for the display.
With a clamp-on work light on top shinning down on the board it was almost like a live X-ray, I could clearly see the traces on both sides and it seemed like I could even see some light through the traces themselves. It quickly showed how bad the two sided etching had gone but also allowed you to shoot for the overlap region. It also should that the drill press quill was not well aligned and that there was probably some runout due to the chuck being slightly angled from the shaft, but then again it was a bottom priced HF so these things are pretty much a given anyhow.
Mounting the camera off to the side with only the angled mirror under the holes eliminated the need for a vacuum and also meant that I could easily mount/unmount boards or position them by hand for each hole so that I had more control. Also the top side was open and clearly visible so I could switch back and forth between TV screen and looking straight at the board and drill bit.
The CMOS camera modules are about a inch cubed and are typically $40. There are similar USB cameras but they tie up a whole computer, not just a throw away old tv set.
-- "Creativity is intelligence having fun." — Albert Einstein
|
On Sat, 9 Mar 2019 10:14:09 -0600, you wrote: Harvey,
? Ok, so after re-reading this again, did you build this from scratch
or from exiting technologies? Scratch. The PC boards for the processor and display driver and so on are home made double sided. I did not make the linear rail, bought that. Camera ditto. Stepper driver was homemade, another PC board, power supply wasn't. Basic support stand wasn't homemade. Programming was a special purpose program, don't think I used an operating system on this one. however the display driver and such were off the shelf, but my shelf. Box was repurposed from an old disk drive enclosure (which is where I got the power supply). Sounds like a pretty complex project. I
won't be attempting that any time soon. :) But I sure would like to see
a pic of it. I'll work on getting pictures of it. My Apache Laminator arrived yesterday and the kit to modify
it the day before, so I am going to get started on that shortly. Your
project listed below is very cool but I don't know that I would ever
need to go that far into drilling my simple projects. I may see about
putting my USB magnifier to good use though as the eyes are getting older... The techniques I needed to be able to do 10/10 double sided boards with relatively small vias, and those boards were pretty packed, at least as far as traces were concerned. I got tired of not having the top layer match the bottom layer. I have some ruined boards because of that. Considering the work needed to make a decent board, well, I wanted to maximize the return on the effort. Harvey
Thanks
On 3/8/2019 10:51 AM, Harvey White wrote:
On Fri, 8 Mar 2019 08:25:31 -0600, you wrote
So you use a tv camera now for your
drilling? I have one of those cheap USB cameras that is a magnifier. Is
that what you used? Actually, no. It's a bit more elaborate than that.
I have a linear rail that has about 6 inches of travel, then machined
a holder that holds the clamp for a proxxon drill. The 12 volt
version works just fine. That is driven by a linear stepper motor
(shaft attached, goes in and out of the motor).
That in turn is driven by an old, but standard design (L297/L298
stepper driver system). There are sensors on the linear rail for
bottom sensing and top sensing.
I found an old Pace desoldering stand, the kind used for a hot air
desolderer. It has a fixed height arm with a rack and pinion stage
for lowering the soldering tool.
Cut a hole in that base and mounted the proxxon upside down so it goes
through the center of the hole. Mounted an old vacuum cleaner nozzle
with a flexible extension so it removes debris from the underside.
On the top slide, I mounted a surveilance TV camera, this one runs on
12 volts too (most run on 24vac, and they're NOT kidding about the VAC
part because there's a small transformer in there that won't tolerate
DC). With an extender, it short focuses enough that I get
magnification. The small monitor is mounted above the camera.
The electronics allow you to home, and set maximum travel. Pressing a
footswitch starts a drill cycle, turns on the drill, moves it to the
up position, then back to a rest position.
You need to recalibrate the xy position each time you change the drill
bit, however.
With that, I can get very very close (say .001, I think) to the center
of a hole by using the crosshairs on the monitor. Some 3D printing
would help out the project, since the original design was to use the
vacuum to hold the board down once the drill bit moved up. That
didn't work as well.
So no, no USB camera. You could use one easily enough. The
electronics could be duplicated easily enough with an arduino, but I
used a board that was designed to run a small graphics display that I
had a few of....
So you get to see the position, and where it is in the cycle.
A bit of overkill, perhaps, but it has proven its worth in board
drilling. It does, by design, completely eliminate the parallax
problem which was a great inconvenience.
Harvey
Thanks
|
Harvey,
? Ok, so after re-reading this again, did you build this from scratch or from exiting technologies? Sounds like a pretty complex project. I won't be attempting that any time soon. :) But I sure would like to see a pic of it. My Apache Laminator arrived yesterday and the kit to modify it the day before, so I am going to get started on that shortly. Your project listed below is very cool but I don't know that I would ever need to go that far into drilling my simple projects. I may see about putting my USB magnifier to good use though as the eyes are getting older...
Thanks
toggle quoted message
Show quoted text
On 3/8/2019 10:51 AM, Harvey White wrote: On Fri, 8 Mar 2019 08:25:31 -0600, you wrote
So you use a tv camera now for your
drilling? I have one of those cheap USB cameras that is a magnifier. Is
that what you used? Actually, no. It's a bit more elaborate than that.
I have a linear rail that has about 6 inches of travel, then machined
a holder that holds the clamp for a proxxon drill. The 12 volt
version works just fine. That is driven by a linear stepper motor
(shaft attached, goes in and out of the motor).
That in turn is driven by an old, but standard design (L297/L298
stepper driver system). There are sensors on the linear rail for
bottom sensing and top sensing.
I found an old Pace desoldering stand, the kind used for a hot air
desolderer. It has a fixed height arm with a rack and pinion stage
for lowering the soldering tool.
Cut a hole in that base and mounted the proxxon upside down so it goes
through the center of the hole. Mounted an old vacuum cleaner nozzle
with a flexible extension so it removes debris from the underside.
On the top slide, I mounted a surveilance TV camera, this one runs on
12 volts too (most run on 24vac, and they're NOT kidding about the VAC
part because there's a small transformer in there that won't tolerate
DC). With an extender, it short focuses enough that I get
magnification. The small monitor is mounted above the camera.
The electronics allow you to home, and set maximum travel. Pressing a
footswitch starts a drill cycle, turns on the drill, moves it to the
up position, then back to a rest position.
You need to recalibrate the xy position each time you change the drill
bit, however.
With that, I can get very very close (say .001, I think) to the center
of a hole by using the crosshairs on the monitor. Some 3D printing
would help out the project, since the original design was to use the
vacuum to hold the board down once the drill bit moved up. That
didn't work as well.
So no, no USB camera. You could use one easily enough. The
electronics could be duplicated easily enough with an arduino, but I
used a board that was designed to run a small graphics display that I
had a few of....
So you get to see the position, and where it is in the cycle.
A bit of overkill, perhaps, but it has proven its worth in board
drilling. It does, by design, completely eliminate the parallax
problem which was a great inconvenience.
Harvey
Thanks
|
Re: Bubble Tank DIY Plans
I tested that link on my wife's PC and she hasn't got Dropbox. It downloaded OK. So I don't understand what is happening on other people's computers.
I do agree that dropbox could be much more friendly and the reliance of Adobe Flash to video stream in a world that is turning it's face away from flash (and an Apple world that has never supported it) is a bad mark for the company.
Oh well, it's not that important. It's a fridge door jug that in the UK I got from DunElm. Your imagination can probably do the rest.
73
Tony G4WIF
|
So you use a tv camera now for your
drilling? I have one of those cheap USB cameras that is a magnifier. Is
that what you used? Actually, no. It's a bit more elaborate than that.
I have a linear rail that has about 6 inches of travel, then machined
a holder that holds the clamp for a proxxon drill. The 12 volt
version works just fine. That is driven by a linear stepper motor
(shaft attached, goes in and out of the motor).
That in turn is driven by an old, but standard design (L297/L298
stepper driver system). There are sensors on the linear rail for
bottom sensing and top sensing.
I found an old Pace desoldering stand, the kind used for a hot air
desolderer. It has a fixed height arm with a rack and pinion stage
for lowering the soldering tool.
Cut a hole in that base and mounted the proxxon upside down so it goes
through the center of the hole. Mounted an old vacuum cleaner nozzle
with a flexible extension so it removes debris from the underside.
On the top slide, I mounted a surveilance TV camera, this one runs on
12 volts too (most run on 24vac, and they're NOT kidding about the VAC
part because there's a small transformer in there that won't tolerate
DC). With an extender, it short focuses enough that I get
magnification. The small monitor is mounted above the camera.
The electronics allow you to home, and set maximum travel. Pressing a
footswitch starts a drill cycle, turns on the drill, moves it to the
up position, then back to a rest position.
You need to recalibrate the xy position each time you change the drill
bit, however.
With that, I can get very very close (say .001, I think) to the center
of a hole by using the crosshairs on the monitor. Some 3D printing
would help out the project, since the original design was to use the
vacuum to hold the board down once the drill bit moved up. That
didn't work as well.
So no, no USB camera. You could use one easily enough. The
electronics could be duplicated easily enough with an arduino, but I
used a board that was designed to run a small graphics display that I
had a few of....
So you get to see the position, and where it is in the cycle.
A bit of overkill, perhaps, but it has proven its worth in board
drilling. It does, by design, completely eliminate the parallax
problem which was a great inconvenience.
Harvey
Wow! Sounds very elaborate. I would like to see a pic of that setup. :) I have many questions about it but will post back in the morning. Too cool! Thanks
|
Re: Bubble Tank DIY Plans
Looks like a good cheap quick etching tank. But I am going to build one. :-) The plans from the Radio Electronics magazine I got from Jim.
Thanks
toggle quoted message
Show quoted text
On 3/8/2019 9:09 AM, Tony Smith wrote: I got a couple for free along with a couple of air pumps, maybe someone was
using them as fish tanks.
They're about 250 x 200 x 75mm, perhaps a bit bigger than I'd like but for
the price I'm happy. I didn't realise they were vases until I saw something
similar in a shop.
I use CuCl to etch; I made lids for the glass tanks when not in use, but
also have them in a plastic tub (spills, glass and all that) away from my
tools.
Tony
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Dave
Sent: Friday, 8 March 2019 2:22 AM
To: [email protected]
Subject: Re: [homebrewpcbs] Bubble Tank DIY Plans
I had found the guy on the web using the vase. Looked good to me. Then I
thought of using those square glass building blocks with the oval cutout
on one side. But in the end I am going to build the one from the Radio
Electronics magazine.
On 3/7/2019 8:35 AM, Tony Smith wrote:
If you decide DIY is a bit much, a search for 'rectangular vase' will turn
up plenty of glass containers in practically any size you want, for
under
$20 or so.
This sort of thing:
Inch/dp/B009AO0EPI/ref=pd
_lpo_vtph_201_lp_img_2. I found a similar couple in my travels a long
time
ago, that's what I use for etching.
You can also check scientific places for similar things, but beware of
sticker shock.
Tony
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Dave
Sent: Wednesday, 6 March 2019 1:10 AM
To: [email protected]
Subject: [homebrewpcbs] Bubble Tank DIY Plans
So I want to build a bubble tank. Anybody have any best methods or DIY
plans? I am pretty sure my boards will remain small for the foreseeable
future so I don't think I need an aquarium. :) I assume plastic is the
best after glass and likely no metal parts touching the solution. An
aquarium pump should work, proven designs are what I am after.
Thanks
|
Re: Can I convert these .pdf images to Gerber??
I have luck with using the free “image to gerber” converter (free software). It took a while to figure out the scaling concern and after that, the converter worked really well. I did not experience any resolution issue with it. Rather, I was taken aback by the “outline not detected” error when I uploaded the gerbers’ zip file to a PCB fabrication website. After a few days of frustrating attempts to resolve the issue with the outline layer gerber, my efforts paid off and I successfully got the PCBs fabricated. They arrived in my mailbox safely, much to my delight. Here’s a step-by-step video for anyone who is keen on going the same route. 
|
On Fri, 8 Mar 2019 08:25:31 -0600, you wrote:
On 3/7/2019 7:46 PM, Harvey White wrote:
<snip>
??? ??? ??? ??? ??? ??? ??? ??? So you use a tv camera now for your
drilling? I have one of those cheap USB cameras that is a magnifier. Is
that what you used?
Actually, no. It's a bit more elaborate than that. I have a linear rail that has about 6 inches of travel, then machined a holder that holds the clamp for a proxxon drill. The 12 volt version works just fine. That is driven by a linear stepper motor (shaft attached, goes in and out of the motor). That in turn is driven by an old, but standard design (L297/L298 stepper driver system). There are sensors on the linear rail for bottom sensing and top sensing. I found an old Pace desoldering stand, the kind used for a hot air desolderer. It has a fixed height arm with a rack and pinion stage for lowering the soldering tool. Cut a hole in that base and mounted the proxxon upside down so it goes through the center of the hole. Mounted an old vacuum cleaner nozzle with a flexible extension so it removes debris from the underside. On the top slide, I mounted a surveilance TV camera, this one runs on 12 volts too (most run on 24vac, and they're NOT kidding about the VAC part because there's a small transformer in there that won't tolerate DC). With an extender, it short focuses enough that I get magnification. The small monitor is mounted above the camera. The electronics allow you to home, and set maximum travel. Pressing a footswitch starts a drill cycle, turns on the drill, moves it to the up position, then back to a rest position. You need to recalibrate the xy position each time you change the drill bit, however. With that, I can get very very close (say .001, I think) to the center of a hole by using the crosshairs on the monitor. Some 3D printing would help out the project, since the original design was to use the vacuum to hold the board down once the drill bit moved up. That didn't work as well. So no, no USB camera. You could use one easily enough. The electronics could be duplicated easily enough with an arduino, but I used a board that was designed to run a small graphics display that I had a few of.... So you get to see the position, and where it is in the cycle. A bit of overkill, perhaps, but it has proven its worth in board drilling. It does, by design, completely eliminate the parallax problem which was a great inconvenience. Harvey
Thanks
|
Re: Bubble Tank DIY Plans
I got a couple for free along with a couple of air pumps, maybe someone was
using them as fish tanks.
They're about 250 x 200 x 75mm, perhaps a bit bigger than I'd like but for
the price I'm happy. I didn't realise they were vases until I saw something
similar in a shop.
I use CuCl to etch; I made lids for the glass tanks when not in use, but
also have them in a plastic tub (spills, glass and all that) away from my
tools.
Tony
toggle quoted message
Show quoted text
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Dave
Sent: Friday, 8 March 2019 2:22 AM
To: [email protected]
Subject: Re: [homebrewpcbs] Bubble Tank DIY Plans
I had found the guy on the web using the vase. Looked good to me. Then I
thought of using those square glass building blocks with the oval cutout
on one side. But in the end I am going to build the one from the Radio
Electronics magazine.
On 3/7/2019 8:35 AM, Tony Smith wrote:
If you decide DIY is a bit much, a search for 'rectangular vase' will turn up plenty of glass containers in practically any size you want, for
under $20 or so.
This sort of thing:
Inch/dp/B009AO0EPI/ref=pd
_lpo_vtph_201_lp_img_2. I found a similar couple in my travels a long
time ago, that's what I use for etching.
You can also check scientific places for similar things, but beware of
sticker shock.
Tony
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Dave
Sent: Wednesday, 6 March 2019 1:10 AM
To: [email protected]
Subject: [homebrewpcbs] Bubble Tank DIY Plans
So I want to build a bubble tank. Anybody have any best methods or DIY
plans? I am pretty sure my boards will remain small for the foreseeable
future so I don't think I need an aquarium. :) I assume plastic is the
best after glass and likely no metal parts touching the solution. An
aquarium pump should work, proven designs are what I am after.
Thanks
|
Re: Bubble Tank DIY Plans
Lots of interesting stuff to see there.
Thanks
On 3/7/2019 5:40 PM, Harald Milatz via
Groups.Io wrote:
toggle quoted message
Show quoted text
Thanks:)
Maybe you can use the other manuals/tips from my site about
pcb:
even "cold"
exposure unit
exposure unit LED
silkcreen
|
On 3/7/2019 7:47 PM, Harvey White wrote: On Thu, 7 Mar 2019 12:24:25 -0600, you wrote:
Harvey,
? My paste went missing. My Grizzly Shear Manual states:
For best results, never cut any piece narrower than eight times the
thickness of the material. For example 1?2" strip of .06 mild steel. So
if I cut down the center of a 2" copper board it may actually work. I
won't know until I try. It will. Nothing stops you from taking some 1/4 inch steel plate and
using it as a clamp to hold the board down. You have to worry about
flex and the board bending and getting caught between the blade and
the shear plate, of course.
Harvey
Looks like problem solved before I start. :) One time I was using the sheer and I got my finger under a part of the auto hold down bar. I started to step on the pedal and I actually started to smash my finger. Lucky I wasn't doing the STOMP method on that cut. I learned a valuable lesson that day. More than one I guess. You want to be the only one using the machine by yourself (unless you are cutting 4x8 sheets). I would hate to have my wife helping and smash her finger, or anyone else for that matter.
|
On 3/7/2019 7:46 PM, Harvey White wrote:
Thanks Harvey. I have a 52" shear (Grizzly) and an 8" plate shear and a
HF throatless shear. So I have the shears! My manual for my Grizzly states:
You went bigger than I did, so... that's good, no problem with that,
then.
I did a number of very thin PC boards for replacement LED strips for
otherwise CCFL backlights.
Everything worked well until I had about 2-3 of the 1/8 inch strips
left to cut, then it just didn't work well at all.
When I was young I had access to larger industrial machines. When I went to the local big box stores everything seemed like toys. So I started buying from Enco and Grizzly and got some real machines.
You'll note that the material sheared off fares worse than the
material left behind, but that will vary with setups. I may have to redesign my layout as I only have 3/16 between the pieces
I want to cut out. But I will try it anyhow just in case my shear
handles it nicely. Otherwise I may have to rethink the usefulness of 2x6
copper clad boards or have some waste.
I had/have somewhat of a source that got surplus 0.030 single sided
board, but I generally bought it in 2 foot square sections (they cut
it before it was put out). From that, I got any reasonable number of
boards.
How you cut the board and lay it out depends on what you're actually
doing, and how your tooling works.
??? ??? ??? ??? ??? ??? ??? ??? Now that I know the shear is the magic tool I can buy large boards and cut as needed but if the size is already right, I will just buy as is.
All good info so I can get off to a good start. And I forgot about
mounting holes on this first project too along with a hole to hang the
board. I have room for that though. And while we are on the subject.
What are your thoughts on the 1oz vs 2oz copper. If you're doing a power supply board with board mounted transistors,
heavy current needed, and it's too small for power dissipation
(conductor wise or whatever the manufacturer says when using the PC
board as a heat sink), then you may want 2 oz. I generally don't use
it or need it. It's often easier to make the board bigger and just
use fatter traces.
??? ??? ??? ??? ??? ??? ??? ??? Plus 2oz takes longer to etch. I will buy some 1oz next time and see how I like it.
And when you print out
your pattern do you fill the pads or leave a drill hole. I am thinking
leave the hole. I leave the hole. Firstly, it tends to center the drill bit, but at
higher RPMs, remember that the drill cuts rather quickly.
When I was making boards, and these were double sided, already epoxied
together boards at this step, (trimmed). I needed the light to shine
through the board from the bottom so I could see the hole in the
crosshairs of the TV camera at the top. Always left the hole in,
otherwise I did have to guess.
Another reason why drilling those pilot holes VERY accurately and
using moderately large pins to align the boards was very necessary.
(large pins tend to cant less in the pc board holes, so don't use
dressmaker's pins, use map pins at a minimum.
The crosshatch on the camera monitor helped with centering the holes.
Naturally, the smaller the hole, the worse the problem with accurate
holes. I think I used a #76 drill and #26 wirewrap wire (stripped, of
course).
Harvey
??? ??? ??? ??? ??? ??? ??? ??? So you use a tv camera now for your drilling? I have one of those cheap USB cameras that is a magnifier. Is that what you used? Thanks
|
Interesting. I just checked and Unit Drop Forge is still alive and well. Sometimes a merger is good, other times not so much.
toggle quoted message
Show quoted text
On 3/7/2019 2:45 PM, Harvey Altstadter wrote: Dave,
I worked for a division of Cutler-Hammer when Eaton bought them out in the 1970's.? Eventually, we bought ourselves out of Eaton and became employee owned. Later mergers left no trace of the original company.
On 3/7/2019 10:52 AM, Dave wrote:
Hi Harvey #2,
?Thanks for posting those links. I just downloaded them and will start studying them later today. My boards will be simple and home brew but I like to do things correct too. So that helps. And who knows, maybe I will get more involved than I think and actually need a board house to make my boards. My? dad worked for Unit Drop Forge which I believe Eaton bought them out. But they were a large forging plant and made crankshafts and other things for Caterpillar.
|
Re: Bubble Tank DIY Plans
Danke sehr!
Donald.
--
*Plain Text* email -- it's an accessibility issue
() no proprietary attachments; no html mail
/\ <>
toggle quoted message
Show quoted text
On 07-Mar-2019 18:40, Harald Milatz via Groups.Io wrote: Thanks:)
Maybe you can use the other manuals/tips from my site about pcb:
even "cold"
Toner-Transfer-Methode - Layout auf eine Platine übertragen <>
Toner-Transfer-Methode - Layout auf eine Platine übertragen
Mit der Toner-Transfer-Methode ein Layout auf eine Platine übertragen. Hier siehst du wie das geht. So kann man ...
<>
exposure unit
Belichtungsger?t - Anleitung für den Selbstbau aus einfachen Mitteln <>
Belichtungsger?t - Anleitung für den Selbstbau aus einfachen Mitteln
Dieses Belichtungsger?t habe ich aus einem alten Scanner und einem Gesichtsbr?uner gebaut. Der Selbstbau ist rec...
<>
exposure unit LED
Belichtungsger?t mit UV-LEDs - Hier zeige ich den Selbstbau. <>
Belichtungsger?t mit UV-LEDs - Hier zeige ich den Selbstbau.
UV-Belichtungsger?t mit UV-LEDs im Eigenbau - Hier zeige ich euch wie man so ein Belichtungsger?t bauen kann. Au...
<>
Das Verzinnen der Platine ist ein wichtiger und einfacher Schritt <>
Das Verzinnen der Platine ist ein wichtiger und einfacher Schritt
Mit Fittingsl?tpaste kann man sehr einfach eine Platine verzinnen. Das Ergebnis ist besser als das Verzinnen mit...
<>
silkcreen
Der Bestückungsdruck für Platinen ist leicht gemacht und geht schnell. <>
Der Bestückungsdruck für Platinen ist leicht gemacht und geht schnell.
Der Bestückungsdruck l?sst eine Platine professioneller aussehen, hilft beim Bestücken und um sp?ter leicht ein ...
<>
|
"You have to worry about
flex and the board bending and getting caught between the blade and
the shear plate, of course." There's an adjustment for that on the HFTools sheer...tighten the bolt/nut in the center of the blade support in back of the machine to reduce the amount of flex in that support. Charlie On Thu, 07 Mar 2019 20:47:46 -0500 "Harvey White" <madyn@...> writes: On Thu, 7 Mar 2019 12:24:25 -0600, you wrote:
Harvey,
My paste went missing. My Grizzly Shear Manual states:
For best results, never cut any piece narrower than eight times the thickness of the material. For example 1?2" strip of .06 mild steel. So
if I cut down the center of a 2" copper board it may actually work. I
won't know until I try. It will. Nothing stops you from taking some 1/4 inch steel plate
and
using it as a clamp to hold the board down. You have to worry about
flex and the board bending and getting caught between the blade and
the shear plate, of course.
Harvey
|
On Thu, 7 Mar 2019 12:24:25 -0600, you wrote: Harvey,
? My paste went missing. My Grizzly Shear Manual states:
For best results, never cut any piece narrower than eight times the
thickness of the material. For example 1?2" strip of .06 mild steel. So
if I cut down the center of a 2" copper board it may actually work. I
won't know until I try. It will. Nothing stops you from taking some 1/4 inch steel plate and using it as a clamp to hold the board down. You have to worry about flex and the board bending and getting caught between the blade and the shear plate, of course. Harvey
|
On Thu, 7 Mar 2019 11:41:33 -0600, you wrote: On 3/7/2019 10:04 AM, Harvey White wrote: <snip> Thanks Harvey. I have a 52" shear (Grizzly) and an 8" plate shear and a
HF throatless shear. So I have the shears! My manual for my Grizzly states:
You went bigger than I did, so... that's good, no problem with that, then. I did a number of very thin PC boards for replacement LED strips for otherwise CCFL backlights. Everything worked well until I had about 2-3 of the 1/8 inch strips left to cut, then it just didn't work well at all. <snip>
You'll note that the material sheared off fares worse than the
material left behind, but that will vary with setups. I may have to redesign my layout as I only have 3/16 between the pieces
I want to cut out. But I will try it anyhow just in case my shear
handles it nicely. Otherwise I may have to rethink the usefulness of 2x6
copper clad boards or have some waste.
I had/have somewhat of a source that got surplus 0.030 single sided board, but I generally bought it in 2 foot square sections (they cut it before it was put out). From that, I got any reasonable number of boards. How you cut the board and lay it out depends on what you're actually doing, and how your tooling works.
All good info so I can get off to a good start. And I forgot about
mounting holes on this first project too along with a hole to hang the
board. I have room for that though. And while we are on the subject.
What are your thoughts on the 1oz vs 2oz copper. If you're doing a power supply board with board mounted transistors, heavy current needed, and it's too small for power dissipation (conductor wise or whatever the manufacturer says when using the PC board as a heat sink), then you may want 2 oz. I generally don't use it or need it. It's often easier to make the board bigger and just use fatter traces. And when you print out
your pattern do you fill the pads or leave a drill hole. I am thinking
leave the hole. I leave the hole. Firstly, it tends to center the drill bit, but at higher RPMs, remember that the drill cuts rather quickly. When I was making boards, and these were double sided, already epoxied together boards at this step, (trimmed). I needed the light to shine through the board from the bottom so I could see the hole in the crosshairs of the TV camera at the top. Always left the hole in, otherwise I did have to guess. Another reason why drilling those pilot holes VERY accurately and using moderately large pins to align the boards was very necessary. (large pins tend to cant less in the pc board holes, so don't use dressmaker's pins, use map pins at a minimum. The crosshatch on the camera monitor helped with centering the holes. Naturally, the smaller the hole, the worse the problem with accurate holes. I think I used a #76 drill and #26 wirewrap wire (stripped, of course). Harvey
Thanks
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Re: Bubble Tank DIY Plans
Thanks:) Maybe you can use the other manuals/tips from my site about pcb:
even "cold"
exposure unit
exposure unit LED
silkcreen
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Dave,
I worked for a division of Cutler-Hammer when Eaton bought them out in the 1970's.? Eventually, we bought ourselves out of Eaton and became employee owned. Later mergers left no trace of the original company.
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On 3/7/2019 10:52 AM, Dave wrote: Hi Harvey #2,
?Thanks for posting those links. I just downloaded them and will start studying them later today. My boards will be simple and home brew but I like to do things correct too. So that helps. And who knows, maybe I will get more involved than I think and actually need a board house to make my boards. My? dad worked for Unit Drop Forge which I believe Eaton bought them out. But they were a large forging plant and made crankshafts and other things for Caterpillar.
On 3/7/2019 11:09 AM, Harvey Altstadter wrote:
Dave,
You have asked a lot of thoughtful questions about layout, pad and trace sizes, board margins, etc., and received a lot of good advice. I thought I would point you at some reference material on standards that various organizations use that is available on the Internet.
1. AN3962 from Freescale (now NXP) has a good summary of information about pads, holes, trace sizes, with a rule of thumb for current, spacings for different voltage conditions, and appears to be based upon IPC standards. Find it here:
2. Colonial DFM Guidelines has more information on board mechanics. It is useful if you are going to have your boards manufactured by a board house. Find it here:
3. EATON Corp, Cutler-Hammer Div Printed Circuit Design Guidelines. A very comprehensive design guide that includes information about about device packages, dimensions and board layout. Find it here:
The documents seem to follow IPC guidelines, and are easier to get than the actual IPC standards which are very expensive. There is a high degree of agreement between them, and with much of the information you have been given here. Many more documents are available under a Google search for PCB Layout Guidelines. For specialized types of boards, such as RF and high frequency work, there are documents specific to those areas.
Good hunting
(The other) Harvey
On 3/7/2019 9:04 AM, Harvey White wrote:
On Thu, 7 Mar 2019 09:28:13 -0600, you wrote:
Harvey, thanks again for the detailed post. I also found a trace width
calculator online that helps size for amps. Another question seeing I
have never done this before. I have various tools like a shear, tin
snips, and scroll saw to cut my boards. But what is the best way? I bought the *large* harbor freight shear, 300 some pounds, because I
have a bit of a metal shop.? I'd suggest a smaller one for sheer size
and portability.? Most people deal with pcb material that's 12 inches
wide or less.
And
what is the minimum boarder I need for best or design rules? I have 12
little circuits that fit on a 2x6 copper clad board but they looked
crowed so I changed it to 10. The gap between the long side center is
3/16". If I cut or sheer accurately is that enough meat left on the sides?
In a sense, you don't care how much distance is left between the board
and board edge, it's nominally no less than two trace spacings. The
limit is how close you can get to the trace when cutting.? For a
shear, I'd say that you'd want about 1/8 inch border minimum around
the board, which says 1/4 inch or so between boards.? Note that you
can always do a rough cut with almost anything and then trim with the
shear.? That's final sheared dimensions, shearing when using panelized
patterns, etc.
Scroll saws will dull almost immediately.
Tile saws with diamond blades may not, and who cares if the board is
wet?? Never tried it myself, though.? Be very cautious with the
fiberglass dust if cutting with a saw.
The main problem with the shear is setting it up properly (it needs
different settings for thicker PC board material), and shearing very
narrow boards along the length.? Board material will tend to want to
pop up and wedge between the blade and table.? This imposes some
practical limits.? (as well as needs hold down clamps of some sort for
those rare boards).
Copper clad, when sheared, may have a tendency to delaminate depending
on the shear settings, so we get a second border limit as well as a
need for an unused border around the whole board pattern (regardless
of what's on it).? I typically wanted about 3/8 to 1/2 an inch around
the board pattern that was unused.? That allowed space to tape the
transfer paper down (one edge only), allowed any lifting effects to be
on a part that didn't have traces, gave me space for holes to hang the
board in the etchant tank, and enough space that trimming the board
with the shear worked well.? Trimming the board to the arbitrary two
trace spacing was fine if the shear would do it.
You'll note that the material sheared off fares worse than the
material left behind, but that will vary with setups.
Harvey
Thanks
On 3/6/2019 3:49 PM, Harvey White wrote:
On Wed, 6 Mar 2019 12:33:13 -0600, you wrote:
Thanks for the info Harvey. I have a new question. What is the closest
pads should be to each other? And if you are making a bunch of small
boards and transferring them to copper for etching what is the minimal
space between designs? In other words, what should the remaining border
width be? Seems I may have placed my circuits too close to the center
and have to shrink the width a little. There's two limits, design and process.
Process limits simply say that you can't physically make the board
like that.? Either too close to the edge, or holes too small, or
pads/traces too small.
Those limits vary with respect to the process, but typically 0.030 or
0.060 are decent limits (roughly 1/16 or 1/32) for pad to pad, and
spacing betwen tracks, but that's process....
Now, voltage wise, that determines the minimum track spacing as well.
I'm not sure of the limits here, you'd have to look that up. Ditto
with track current carrying capacity for width (varies also with
respect to the copper foil thickness).
You also want to allow for heat dissipation for things like resistors.
Typical power resistors are often at the end of longer leads and
spaced off the boards.? Seen scorched boards because of resistors. Now
on the other hand, those resistor long leads will fail any sort of
vibration test.? (military stuff used clamps for bulky parts like
that).
So for home analog stuff, not necessarily digital, you want a small
enough trace that you can put one between the pads of a DIP (more
requires finer stuff than can be happily done at home).
WIthout an autorouter (which is of limited use for home built boards),
I tend to use the airwires (unrouted traces) to determine which parts
need to be near which parts for shortest wire runs, then try to
manually route the shortest wires.? It's a learning process...
Once you go to surface mount parts, the design rules start to change,
but I'm not sure where you are on this design.
Harvey
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Re: Bubble Tank DIY Plans
Attached…? Can you put it somewhere and
tell everyone please.? Thanks.
?
J?J?
?
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From: [email protected]
[mailto:[email protected]] On Behalf Of Dave
Sent: Thursday, March 07, 2019 1:42 PM
To: [email protected]
Subject: Re: [homebrewpcbs] Bubble
Tank DIY Plans
?
Could
you email the file to me? I had the same problem.Email is in the reply to
above.
Thanks,
Dave
On 3/6/2019 4:43 PM,
Paul Galarneau via Groups.Io wrote:
After I logged in, I could see the
file.? I even downloaded it to my computer and watched it, no problem.?
If there is a place I can put it for you, let me know.? I still have it
here.? 28MB. ?I hope it’s ok with the owner…
?
?
J?J
?
?
?
?
?
More than poor programming, Dropbox can only be used
on your account.? The basic (free) does not allow
a person to goto another link and look at the bubble
tank I get error 404. I am logged in and the file is not there
unless I am doing something wrong...
?
On Wed, Mar 6, 2019
at 7:39 AM Paul Galarneau via Groups.Io
<pgsoft51=[email protected]>
wrote:
Yeah, you have to logged in to see the file.? I got the same
message then I logged in.? Message shouldbe changed to?: you have to be
logged in to see this file.? Very crappy programming.?
?
J?J
?
?
Seems the link
doesnt work for me - error 404 - "That file isn’t here anymore".
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