well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...entPage=search

Would appreciate any help in brainstorming a solution. I could cut it but I
need a small square of about 30MM +- .05MM. Maybe a laser cutting service?
That's about the only thing I can think of.

On Tue, 19 Aug 2008 11:37:20 -0500, "Kevin_91B" wrote:

well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...entPage=search

Would appreciate any help in brainstorming a solution. I could cut it but I
need a small square of about 30MM +- .05MM. Maybe a laser cutting service?
That's about the only thing I can think of.


a drill bit in a dremel to cut it slightly oversize, and then pass it
back and forth on a flat surface covered with fine grit, wet or dry
sandpaper that is kept wet to get to the final finished size.

Kevin_91B wrote:
well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...entPage=search

Would appreciate any help in brainstorming a solution. I could cut
it but I
need a small square of about 30MM +- .05MM. Maybe a laser cutting
service?
That's about the only thing I can think of.

What tools do you have and what have you tried that didn't work?

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

Kevin,

A millimg machine would easily do this. Given the tolerance of 0.05 mm I
doubt that any hand tool would work. I've no idea what sort of shop charge
would result but it won't be cheap.

Dave M.

Kevin_91B wrote:
well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...entPage=search

Would appreciate any help in brainstorming a solution. I could cut
it but I need a small square of about 30MM +- .05MM. Maybe a laser
cutting service? That's about the only thing I can think of.

Score it and snap it a bit oversize and then sand to final dimension.
Circuit board material breaks pretty cleanly with a good score-line on it.

On Tue, 19 Aug 2008 18:43:15 -0400, "David L. Martel"
wrote:

Kevin,

A millimg machine would easily do this. Given the tolerance of 0.05 mm I
doubt that any hand tool would work. I've no idea what sort of shop charge
would result but it won't be cheap.

If that is true, make more than one. I think it won't be much extra
for the other ones. In case you ruin the first.

Dave M.

On Tue, 19 Aug 2008 19:38:32 -0400, mm
wrote:

On Tue, 19 Aug 2008 18:43:15 -0400, "David L. Martel"
wrote:

Kevin,

A millimg machine would easily do this. Given the tolerance of 0.05 mm I
doubt that any hand tool would work. I've no idea what sort of shop charge
would result but it won't be cheap.

If that is true, make more than one. I think it won't be much extra
for the other ones. In case you ruin the first.

Dave M.


Motto: There is nothing so simple that it cannot be made more
complicated

On Tue, 19 Aug 2008 11:37:20 -0500, Kevin_91B wrote:

well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...entPage=search

Would appreciate any help in brainstorming a solution. I could cut it but I
need a small square of about 30MM +- .05MM. Maybe a laser cutting service?
That's about the only thing I can think of.

Get a square and put it where you want to cut it and score it a couple of
times with a utility knife, hard. Place the scored line over the edge of a
table and break it off at the scored line.

"RLM" wrote in message
. ..
On Tue, 19 Aug 2008 11:37:20 -0500, Kevin_91B wrote:

well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...entPage=search

Would appreciate any help in brainstorming a solution. I could cut it
but I
need a small square of about 30MM +- .05MM. Maybe a laser cutting
service?
That's about the only thing I can think of.

Get a square and put it where you want to cut it and score it a couple of
times with a utility knife, hard. Place the scored line over the edge of a
table and break it off at the scored line.


Ok thanks for the all the suggestions. I should be able to get it done with
one of these methods.

Rick,

I don't think that a home hobbyist will be able to do this. Look at that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.

On Wed, 20 Aug 2008 07:54:56 -0400, "David L. Martel"
wrote:

Rick,

I don't think that a home hobbyist will be able to do this. Look at that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.


With a micrometer?

wrote in :

On Wed, 20 Aug 2008 07:54:56 -0400, "David L. Martel"
wrote:

Rick,

I don't think that a home hobbyist will be able to do this. Look at
that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.


With a micrometer?



WHY would a PCB -need- such tight tolerances?
what about thermal expansion?

--
Jim Yanik
jyanik
at
kua.net

On Wed, 20 Aug 2008 07:54:56 -0400, David L. Martel wrote:

Rick,

I don't think that a home hobbyist will be able to do this. Look at
that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.

Wet or dry sandpaper. I imagine he really means within .5mm The size board
he is using if it is a home project is possibly only going to have less
than a dozen components. More likely 6-8 components. 30mm x 30mm is about
the size I used for a transistor ignition for a motorcycle. Fits right in
one of the small Radio Shack project boxes. This is the board I used.

http://www.radioshack.com/product/in...Id=2104052&cp=

Cut it with a box (utility) knife, broke off clean and sanded the edge.

On Wed, 20 Aug 2008 12:40:17 -0400, RLM wrote:

On Wed, 20 Aug 2008 07:54:56 -0400, David L. Martel wrote:

Rick,

I don't think that a home hobbyist will be able to do this. Look at
that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.

Wet or dry sandpaper. I imagine he really means within .5mm The size board
he is using if it is a home project is possibly only going to have less
than a dozen components. More likely 6-8 components. 30mm x 30mm is about
the size I used for a transistor ignition for a motorcycle. Fits right in
one of the small Radio Shack project boxes. This is the board I used.

http://www.radioshack.com/product/in...Id=2104052&cp=

Cut it with a box (utility) knife, broke off clean and sanded the edge.

This board is 45mm x 90mm before cutting. I cut it in half and the holes
align with the mounting holes inside the box.

http://www.radioshack.com/product/in...entPage=search

RLM wrote:
....
Cut it with a box (utility) knife, broke off clean and sanded the edge.

This board is 45mm x 90mm before cutting. I cut it in half and the holes
align with the mounting holes inside the box.
....

I can't imagine why the OP thinks he needs such a tolerance anyway (even
if is a typo and meant 0.5 instead of 0.05 mm)...

--

On Wed, 20 Aug 2008 11:54:46 -0500, dpb wrote:

RLM wrote:
...
Cut it with a box (utility) knife, broke off clean and sanded the edge.

This board is 45mm x 90mm before cutting. I cut it in half and the holes
align with the mounting holes inside the box.
...

I can't imagine why the OP thinks he needs such a tolerance anyway (even
if is a typo and meant 0.5 instead of 0.05 mm)...

Perhaps he will share what it is that he is building. My curiosity is up.

I use "Lucy Lu" to chop PCBs;

http://www.pbase.com/eldata/image/66633405

On Aug 20, 3:59*am, "Kevin_91B" wrote:
"RLM" wrote in message

Ok thanks for the all the suggestions. *I should be able to get it done with
one of these methods.

On 20 Aug 2008 16:32:05 GMT, Jim Yanik wrote:

wrote in :

On Wed, 20 Aug 2008 07:54:56 -0400, "David L. Martel"
wrote:

Rick,

I don't think that a home hobbyist will be able to do this. Look at
that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.


With a micrometer?



WHY would a PCB -need- such tight tolerances?
what about thermal expansion?

I don't berlieve the OP is using it as a circuit board. He hasn't told
us what mysterious use he has for it, but he did say it wasn't being
used as a circuit board.

wrote:
On 20 Aug 2008 16:32:05 GMT, Jim Yanik wrote:

wrote in :

On Wed, 20 Aug 2008 07:54:56 -0400, "David L. Martel"
wrote:

Rick,

I don't think that a home hobbyist will be able to do this. Look at
that
0.05 mm tolerance. How will you measure hundredths of a millimeter?

Dave M.


With a micrometer?



WHY would a PCB -need- such tight tolerances?
what about thermal expansion?

I don't berlieve the OP is using it as a circuit board. He hasn't told
us what mysterious use he has for it, but he did say it wasn't being
used as a circuit board.

Well, if nothing else, if clad on both sides with copper, it's a
capacitor.

"RLM" wrote in message
. ..
On Wed, 20 Aug 2008 11:54:46 -0500, dpb wrote:

RLM wrote:
...
Cut it with a box (utility) knife, broke off clean and sanded the edge.

This board is 45mm x 90mm before cutting. I cut it in half and the holes
align with the mounting holes inside the box.
...

I can't imagine why the OP thinks he needs such a tolerance anyway (even
if is a typo and meant 0.5 instead of 0.05 mm)...

Perhaps he will share what it is that he is building. My curiosity is up.


It will be sort of a "dummy" BGA unit which will be run through a machine at
work designed to handle parts of a certain size. Part too small or big,
machine jam.

On Aug 19, 11:37*am, "Kevin_91B" wrote:
well not quite a pcb but this blank board from Radio Shack:

http://www.radioshack.com/product/in...102495&cp=&sr=...

Would appreciate any help in brainstorming a solution. *I could cut it but I
need a small square of about 30MM +- .05MM. * Maybe a laser cutting service?
That's about the only thing I can think of.

A machine shop with a waterjet CNC cutting machine could do that
fairly quickly.

Joe

"Kevin_91B" writes:

Perhaps he will share what it is that he is building. My curiosity is up.

It will be sort of a "dummy" BGA unit which will be run through a machine at
work designed to handle parts of a certain size. Part too small or big,
machine jam.

Are you sure that the correct operation of the machine doesn't depend on
other dimensions of the BGA unit? Any reason you can't simply use a
physically real but electrically dead (and thus scrap) BGA package?

Dave