Hello All,

I recently became a member of this group, and have been catching up
on reading the old posts.

I have been making circuit boards at home with my home made cnc
machine for about 3 years. I work as a tool/die maker, and program cnc
mills at work all day, so I have access to the cam software for making
my boards. (Had access that is, I quit this job and my last day will
be oct,6)

Will miss not having access to the software, so I am glad to hear
about pcb-gcode. I have not had time to use eagle/pcb-gcode yet but
look forward to it.

I have been making my own cutters for milling circuit boards, and
am interested in some feed back from the good people on this list.

In the files section, in the folder called Tools by andrew, ther
are two images of the cutters I have been making to cut boards with.
They are very hard to break, and seem to last a long time. They are
made of carbide, and can cut a path in the copper as small as .007"
wide, as long as the board is held very flat.

I think I could make and sell these tools for less than what is
currently available, but need to know if there is any interest in them.

#1 Have any of you used tools that look like these before?

#2 If any one is interested in trying these tools out, I would like
your input as to the performace of the tools relative to what you use now.

Contact me off list at kn6za@... if you want to try them
out. I have a limited quantity at this point.



Thanks
Andrew Abken

On 9/28/06, kn6za <kn6za@...> wrote:

Hello All,

I think I could make and sell these tools for less than what is
currently available, but need to know if there is any interest in them.

#1 Have any of you used tools that look like these before?

I have not used those particular tools (that is, not the ones you ground),
but I did try the "spade" design before. I ground them myself, so the
geometry was probably sub-par (and spending an hour+ to grind a single bit
wasn't worth it, except that it was fun to try).

One common and annoying problem faced by most people who try to use
V-cutters for milling boards is the varying width of the channel being cut
(pcb boards are not perfectly flat, as we know). I thought that the 'spade'
design could help with that. If I could make the angle at the tip large, and
have some minimal relief going from the widest part of the "spade" and up
the shank, I hoped that the varying depth of cut will not result in much
variance in the width of it (I am not sure if I am describing the geometry
well). It mostly worked, and I had one 12 thou bit survive for about 3 hours
before snapping.

Other bits did not last that long. But the one that did last a few hours
seemed to work fairly well. I do not know what was the cause for the short
longevity -- it could be poor geometry, or maybe my "manufacturing process"
was wrong (I know almost nothing about grinding carbide), or maybe it is an
inherent flaw in the design (the tip ends up being fairly long yet skinny at
12 thou.

So, to answer your question, yes, I tried one of the designs you have
mentioned. It seemed promising, but I did not play with it long enough to
see if it was actually viable for anything but some amateurish tinkering by
me.

Vlad


#2 If any one is interested in trying these tools out, I would like

your input as to the performace of the tools relative to what you use now.

Contact me off list at kn6za@... if you want to try them
out. I have a limited quantity at this point.



Thanks
Andrew Abken







Don't forget to put yourself on the map!
http://www.frappr.com/pcbgcode

Yahoo! Groups Links

--
Vlad's shop
http://www.krupin.net/serendipity/index.php?/categories/2-metalworking

Thanks Vlad for the response, and the input.

I am using a tool and cutter grinder to manufacture the tools so
the geometry of the tools is solid and repeatable. I think this will
help improve the performance quite a bit.

I Have been working on some solutions to the problems you
mention. I think I have nearly worked out the problem of holding
board flat. I have been using a vacuume chuck to hold the boards,
and am trying to refine the design so that I can start selling the
design as a kit. I hope to include vaccume pump, hose, chuck, and
seals for a reasonably affordable price. My experiments indicate at
this point, that the boards can be held without any screws or clamps
that stick up above the surface of the board, wich will make things
so much easier for people. So far it also looks like irregular
shaped, single sided and double sided boards could made with this
process to.


Andrew Abken

HI Andrew,

Good idea! Not having screws/clamps that stick up ABOVE the board could
have saved me a few cutters!

Alan KM6VV

On Fri, 13 Oct 2006 10:58:46 -0700, you wrote:

HI Andrew,

Good idea! Not having screws/clamps that stick up ABOVE the board could
have saved me a few cutters!

I'm working on a vacuum hold down setup for PC board milling. When
it's ready, I'll document it. Should work on a shop vac without much
of a problem, may even vacuum up the dust from the drilling.

Still trying to solve the "illegal phase 0 in main program" error,
though.

Harvey

Alan KM6VV

Thanks Vlad for the response, and the input.

I am using a tool and cutter grinder to manufacture the tools so
the geometry of the tools is solid and repeatable. I think this will
help improve the performance quite a bit.

I Have been working on some solutions to the problems you
mention. I think I have nearly worked out the problem of holding
board flat. I have been using a vacuume chuck to hold the boards,
and am trying to refine the design so that I can start selling the
design as a kit. I hope to include vaccume pump, hose, chuck, and
seals for a reasonably affordable price. My experiments indicate at
this point, that the boards can be held without any screws or clamps
that stick up above the surface of the board, wich will make things
so much easier for people. So far it also looks like irregular
shaped, single sided and double sided boards could made with this
process to.


Andrew Abken

Don't forget to put yourself on the map!
http://www.frappr.com/pcbgcode

Yahoo! Groups Links

Hi Harvey,

That sounds like a good project. What size mill does it fit! I have a CNC'd Sherline Mill.

Alan KM6VV

Harvey White wrote:

On Sat, 14 Oct 2006 08:47:38 -0700, you wrote:

Hi Harvey,

That sounds like a good project. What size mill does it fit! I have a
CNC'd Sherline Mill.

It'll fit anything, you just build it to size.

The design is simple enough, ought to have it working (I think) in
about a week, along with all the other stuff. It's currently on a
custom XYZR table that I built.

Details on that, but not the fixture, at www.dragonworks.info

Harvey

Alan KM6VV

Harvey White wrote:

I'm working on a vacuum hold down setup for PC board milling. When
it's ready, I'll document it. Should work on a shop vac without much
of a problem, may even vacuum up the dust from the drilling.

Still trying to solve the "illegal phase 0 in main program" error,
though.

Harvey

Don't forget to put yourself on the map!
http://www.frappr.com/pcbgcode

Yahoo! Groups Links

Hi Harvey,

Nice web site! let us know when the isolation table is posted!

I'm also curious about the sensitized PCB material. What UV wavelength is it sensitive to? I've heard of various bulbs being used, but I'd like to know the range of UV light wavelengths that can be used. I'm thinking about the possibility of using a high power LED and a lens. The UV LED I'm looking at is at the low end of the UV spectrum.

I will use my CNC to move the LED around on a board, at least that's the plan! I'd also consider using a Laser Diode, but I haven't figured out what to order! I dismantled an old CD reader; it's laser diode (?) had 3 pins, and a little pot and cap right next to it. So I'm not sure how to hook it up to a current regulated power supply. 3 pins?

Funny, I did some google searches for PCB and UV, but couldn't find the information I need.

Alan KM6VV


Harvey White wrote:

Alan,

There is a lot of good info here
http://tinyurl.com/yz3z8g

like:

"...using ultraviolet (UV) radiation in the range of 300 nm (nanometers) to 440 nm."

Regards,
JJ

Hi John,

Thanks! I got my cutters there, but never went through the photo process section. Resist has to be laminated onto a board and is $85 a roll. But the sensitivity is just right; the LED I was thinking of using is 400 nm.

I'll have it continue thinking on this!

Alan KM6VV

John Johnson wrote:

Alan,

Wonder if you could make up some photo pens using leds and hyperdermic needles.
An old HPGL plotter as UV pcb exposure gadget? Seem to remember there was something like this last century:)
Or maybe just needles on a rotary head with single UV led/laser source.

Gavin

From: KM6VV <KM6VV@...>
Reply-To: pcb-gcode@...
To: pcb-gcode@...
Subject: Re: [pcb-gcode] Re: new to group/cutters
Date: Sat, 14 Oct 2006 15:44:32 -0700

Hi John,

Thanks! I got my cutters there, but never went through the photo
process section. Resist has to be laminated onto a board and is $85 a
roll. But the sensitivity is just right; the LED I was thinking of
using is 400 nm.

I'll have it continue thinking on this!

Alan KM6VV

John Johnson wrote:

Alan,

There is a lot of good info here
http://tinyurl.com/yz3z8g

like:

"...using ultraviolet (UV) radiation in the range of 300 nm
(nanometers) to 440 nm."

Regards,
JJ

_________________________________________________________________
See Jet live in LA. Download music for a chance to win! http://ninemsn.com.au/share/redir/adTrack.asp?mode=click&clientID=721&referral=hotmailtagline&URL=http://music.ninemsn.com.au/section.aspx?sectionid=2465§ionname=artistfeature&subsectionid=5692&subsectionname=jet

Hi Gavin,

Good idea! I've put a Repidograph pen into a scraped pen from my 7475; so an LED and a lens wouldn't be that hard. The 7475 would be OK for film, but might be a little tricky with a piece of board. Might be able to tape the board down to a piece of paper (the 7475 is a paper pusher).

I'm thinking it would be a simple job to make up a holder for the LED and lens to fit up to the Sherline Z axis way.

But first, I will need to get some supplies, and run some tests to determine if I can get decent exposure times on the board material.

Alan KM6VV


Gavin McIntosh wrote:

Alan,

Just another idea but can copper be ECMed?
Electro chemical milling in salt water works great on ferrous metals, would it work on pcbs?
Good thing with ECM is no chemicals apart from salt and it is faster than EDM.
I want to etch flexible pcbs, bit hard to do with routers bits.
Hmm might have to sign back onto electroplaters group.

Gavin

From: KM6VV <KM6VV@...>
Reply-To: pcb-gcode@...
To: pcb-gcode@...
Subject: Re: [pcb-gcode] Re: new to group/cutters
Date: Sat, 14 Oct 2006 17:04:35 -0700

Hi Gavin,

Good idea! I've put a Repidograph pen into a scraped pen from my 7475;
so an LED and a lens wouldn't be that hard. The 7475 would be OK for
film, but might be a little tricky with a piece of board. Might be able
to tape the board down to a piece of paper (the 7475 is a paper pusher).

I'm thinking it would be a simple job to make up a holder for the LED
and lens to fit up to the Sherline Z axis way.

But first, I will need to get some supplies, and run some tests to
determine if I can get decent exposure times on the board material.

Alan KM6VV


Gavin McIntosh wrote:

Alan,

Wonder if you could make up some photo pens using leds and hyperdermic
needles.
An old HPGL plotter as UV pcb exposure gadget? Seem to remember there was
something like this last century:)
Or maybe just needles on a rotary head with single UV led/laser source.

Gavin

_________________________________________________________________
Thousands of sexy singles online http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Flavalife9%2Eninemsn%2Ecom%2Eau%2Fclickthru%2Fclickthru%2Eact%3Fid%3Dninemsn%26context%3Dan99%26locale%3Den%5FAU%26a%3D23768&_t=754951090&_r=endtext_lavalife_oct_1000&_m=EXT

Hi Gavin,

I don't know anything about ECM. I'm guessing that the copper would not react as fast (if at all) with the salt electrolyte. but it's an idea. Of course that could start to get messy. ECM/EDM approaches could be a possibility. Are you set up to experiment?

The "think and tinker" photo-resist needs to be "laminated" onto the PCB. And so far it's $85 for a roll, it's an expensive test. But if I can expose it with a LED, then there are some possibilities there.

Alan KM6VV

Gavin McIntosh wrote:

You can buy boards with th efilm pre_applied in samller quanities...
Garry

Date sent: Sun, 15 Oct 2006 13:44:14 -0700
From: KM6VV <KM6VV@...>
Subject: Re: [pcb-gcode] Re: new to group/cutters
To: pcb-gcode@...
Send reply to: pcb-gcode@...

Alan,

ECM works by electrolysis, two electrodes, conductive fluid(salt water) and lower voltage power supply, not high voltage spark like EDM.
The reverse to electroplating? hmm may need copper sulfate solution instead of salt?

How much on the roll?
Could be useful for my model train brass etches?
RE -resist, maybe a spin coater would be the best way to make a even layer on the pcb.
Get old turntable and put bigger motor on it?

Gavin

From: KM6VV <KM6VV@...>
Reply-To: pcb-gcode@...
To: pcb-gcode@...
Subject: Re: [pcb-gcode] Re: new to group/cutters
Date: Sun, 15 Oct 2006 13:44:14 -0700

Hi Gavin,

I don't know anything about ECM. I'm guessing that the copper would not
react as fast (if at all) with the salt electrolyte. but it's an idea.
Of course that could start to get messy. ECM/EDM approaches could be a
possibility. Are you set up to experiment?

The "think and tinker" photo-resist needs to be "laminated" onto the
PCB. And so far it's $85 for a roll, it's an expensive test. But if I
can expose it with a LED, then there are some possibilities there.

Alan KM6VV

Gavin McIntosh wrote:

Alan,

Just another idea but can copper be ECMed?
Electro chemical milling in salt water works great on ferrous metals,

would

it work on pcbs?
Good thing with ECM is no chemicals apart from salt and it is faster than
EDM.
I want to etch flexible pcbs, bit hard to do with routers bits.
Hmm might have to sign back onto electroplaters group.

Gavin

_________________________________________________________________
Research and compare new cars side by side at carpoint.com.au http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fsecure%2Dau%2Eimrworldwide%2Ecom%2Fcgi%2Dbin%2Fa%2Fci%5F450304%2Fet%5F2%2Fcg%5F801459%2Fpi%5F1004813%2Fai%5F833884&_t=54321&_r=hotmail_endtext&_m=EXT

On Sat, 14 Oct 2006 12:40:05 -0700, you wrote:

Hi Harvey,

Nice web site! let us know when the isolation table is posted!

I'm doing a final build/straighten up on the xyzr table, which
includes the power supply, limit and home sensors, etc. I think that
by the end of the week I should have it done. Most of this afternoon
was taken up by refinishing the aluminum and putting it back together.
I have a few design problems I need to rework.

Hopefully by the end of the week. It's nothing much, just a flat
plate, a sealed wooden wall, and a sacrificial wooden layer (probably
particle board) for the top, perhaps a coat of white spray paint. I
have a thin hose that came off a cpap unit, which is spring hose,
won't collapse. I'll use that for a vacuum hose for the hold down. A
layer of saran wrap will seal the smaller boards.

I'm also curious about the sensitized PCB material. What UV wavelength
is it sensitive to?

MG chemicals says to use 8500K bulbs, which is blueish daylight and
NOT shortwave UV.

Kodak KPR (don't use! nasty stuff) is sensitive to shortwave UV,
that's a bare mercury vapor arc... VERY nasty stuff.

GC chemicals is sensitive to longwave UV. I have 6 UV "blacklights"
of about 15 watts each. With some experimentation, the right exposure
seems to be about 3 minutes. Density of the positive is critical.
There's some information in the toner transfer section of the website
to explain that.

I have some old injectorall boards, but have never gotten them to
expose correctly. No idea why. They're probably bad.

The MG chemicals boards will also expose under longwave UV and with
about the same exposure as the GC chemicals.

Having moved from Alabama to Florida, my source for less expensive
photosensitive boards (4 something for a 4x6 SS board) has dried up.
Mechanical etching and toner transfer are the remaining options if I
want to do them myself.

I've heard of various bulbs being used, but I'd
like to know the range of UV light wavelengths that can be used. I'm
thinking about the possibility of using a high power LED and a lens.
The UV LED I'm looking at is at the low end of the UV spectrum.

That would be about the right part. However, that'll work mostly on
the negative photoresist. (again, see website on KPR). Unless you
make the system use the same instructions as pcb-gcode and treat the
UV as a milling bit. If you're going to do that, it's easier just to
go with a transparency.

The original use I was thinking of for the blue/UV LED was to make a
photoplotter that would go directly onto Kodalith, which would produce
a very dense positive. Not sure that it's needed any more.

However, Kodalith is no longer produced, from what I'm told.

I will use my CNC to move the LED around on a board, at least that's the
plan! I'd also consider using a Laser Diode, but I haven't figured out
what to order! I dismantled an old CD reader; it's laser diode (?) had
3 pins, and a little pot and cap right next to it. So I'm not sure how
to hook it up to a current regulated power supply. 3 pins?

No idea, but as I have said, I've heard that the laser diodes are
picky. The CD reader ones are IR, which is exactly what
photosensitive boards are NOT sensitive to. They are handled under
red/yellow safelight conditions (as is kodalith).

You'd need a blue/green laser, which is $$$$ right now.

OR perhaps a really bright white or UV led... much less money, not
coherent, but much more forgiving.

Funny, I did some google searches for PCB and UV, but couldn't find the
information I need.

Look at the GC electronics website, the Injectorall website, and the
MG chemicals website for their exposure frames and lights.

Harvey

Alan KM6VV


Harvey White wrote:

It'll fit anything, you just build it to size.

The design is simple enough, ought to have it working (I think) in
about a week, along with all the other stuff. It's currently on a
custom XYZR table that I built.

Details on that, but not the fixture, at www.dragonworks.info

Harvey

Don't forget to put yourself on the map!
http://www.frappr.com/pcbgcode

Yahoo! Groups Links

Hi Harvey,

More useful information! And a good summation of the etch process. I'm
still on my UV LED / PCB quest, but you've shed some light on the subject!

Thanks,

Alan KM6VV

HI Gavlin,

The photo resist was listed by think-and-tinker:

http://www.thinktink.com/cgi-bin/cart.pl?db|photopolymers.dat|Photoresist

It looks like 50' x 12" wide roll for about $85. GC photosensitized PCB
stock is not cheap!

I could use a few feet of that for my experiments! The "lamination" phase
might be a little hassle. A fuser out of a laser printer might do the job,
I don't know. Do the job by hand and an ordinary flat iron?

Reverse electroplating? Would you have to make contact to all the areas to
be removed then? That could probably be done.

Almost sounds like EDM could "burn off" the isolation tool paths as well. I
wonder if anyone has tried that? That could work directly from pcb-gcode
output Gcode files as well. Might not be very fast, 'tho.

Alan KM6VV

On Mon, 16 Oct 2006 08:43:23 -0700, you wrote:

Hi Harvey,

More useful information! And a good summation of the etch process. I'm
still on my UV LED / PCB quest, but you've shed some light on the subject!

Shortwave, Longwave, or just plain 8500K?

<grin>

Harvey

Thanks,

Alan KM6VV

Behalf Of Harvey White

I'm doing a final build/straighten up on the xyzr table, which
includes the power supply, limit and home sensors, etc. I think that
by the end of the week I should have it done. Most of this afternoon
was taken up by refinishing the aluminum and putting it back together.
I have a few design problems I need to rework.

Hopefully by the end of the week. It's nothing much, just a flat
plate, a sealed wooden wall, and a sacrificial wooden layer (probably
particle board) for the top, perhaps a coat of white spray paint. I
have a thin hose that came off a cpap unit, which is spring hose,
won't collapse. I'll use that for a vacuum hose for the hold down. A
layer of saran wrap will seal the smaller boards.

I'm also curious about the sensitized PCB material. What UV wavelength
is it sensitive to?

MG chemicals says to use 8500K bulbs, which is blueish daylight and
NOT shortwave UV.

Kodak KPR (don't use! nasty stuff) is sensitive to shortwave UV,
that's a bare mercury vapor arc... VERY nasty stuff.

GC chemicals is sensitive to longwave UV. I have 6 UV "blacklights"
of about 15 watts each. With some experimentation, the right exposure
seems to be about 3 minutes. Density of the positive is critical.
There's some information in the toner transfer section of the website
to explain that.

I have some old injectorall boards, but have never gotten them to
expose correctly. No idea why. They're probably bad.

The MG chemicals boards will also expose under longwave UV and with
about the same exposure as the GC chemicals.

Having moved from Alabama to Florida, my source for less expensive
photosensitive boards (4 something for a 4x6 SS board) has dried up.
Mechanical etching and toner transfer are the remaining options if I
want to do them myself.

I've heard of various bulbs being used, but I'd
like to know the range of UV light wavelengths that can be used. I'm
thinking about the possibility of using a high power LED and a lens.
The UV LED I'm looking at is at the low end of the UV spectrum.

That would be about the right part. However, that'll work mostly on
the negative photoresist. (again, see website on KPR). Unless you
make the system use the same instructions as pcb-gcode and treat the
UV as a milling bit. If you're going to do that, it's easier just to
go with a transparency.

The original use I was thinking of for the blue/UV LED was to make a
photoplotter that would go directly onto Kodalith, which would produce
a very dense positive. Not sure that it's needed any more.

However, Kodalith is no longer produced, from what I'm told.

I will use my CNC to move the LED around on a board, at least that's the
plan! I'd also consider using a Laser Diode, but I haven't figured out
what to order! I dismantled an old CD reader; it's laser diode (?) had
3 pins, and a little pot and cap right next to it. So I'm not sure how
to hook it up to a current regulated power supply. 3 pins?

No idea, but as I have said, I've heard that the laser diodes are
picky. The CD reader ones are IR, which is exactly what
photosensitive boards are NOT sensitive to. They are handled under
red/yellow safelight conditions (as is kodalith).

You'd need a blue/green laser, which is $$$$ right now.

OR perhaps a really bright white or UV led... much less money, not
coherent, but much more forgiving.

Funny, I did some google searches for PCB and UV, but couldn't find the
information I need.

Look at the GC electronics website, the Injectorall website, and the
MG chemicals website for their exposure frames and lights.

Harvey

Don't forget to put yourself on the map!
http://www.frappr.com/pcbgcode

Yahoo! Groups Links