Homebrew PCBs

Hi All!

I am new to the list trying to learn about different PC board 
substrates.  I think CEM-1 may be what I want but am trying to 
confirm.  I've scoured the net today, as well as searched this list's 
archives, but haven't seen exactly what I am trying to find out ...my 
apologies if I've missed it somewhere.

I have some PC board stock (purchased in 2002) that measures .056 in 
thickness and is single-sided board.  It is an off-white/light tan 
color on the unclad side and appears whitish on the cut sides.  Under 
magnification the cut edges appear to be almost an open cell type resin 
(possibly a paper/resin combo?).  It's definitely not a stranded fiber 
as is some other stock that I have.  Anyone have any ideas on what this 
substrate is?  

I want to get some more of this, or similar board, and am planning to 
cut it into very small sizes.  It looks like .062 single sided board 
would work for me and be relatively easy to cut.  I plan to cut using 
either my small hobby table saw with suitable blade or possibly my band 
saw with metal cutting blade.

Easy (relatively) cutting is my main objectives, other structural and 
electrical properties are not critical for my needs.  Any help in 
determining the best material for my needs is appreciated.

Thanks,
John Fell

----- Original Message ----- 

From: "lnrrfan" <spfell@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Tuesday, February 27, 2007 3:28 AM
Subject: [Homebrew_PCBs] Trying to learn about substrates


> Hi All!
>
> I am new to the list trying to learn about different PC board
> substrates.  I think CEM-1 may be what I want but am trying to
> confirm.  I've scoured the net today, as well as searched this list's
> archives, but haven't seen exactly what I am trying to find out ...my
> apologies if I've missed it somewhere.
>
> I have some PC board stock (purchased in 2002) that measures .056 in
> thickness and is single-sided board.  It is an off-white/light tan
> color on the unclad side and appears whitish on the cut sides.  Under
> magnification the cut edges appear to be almost an open cell type resin
> (possibly a paper/resin combo?).  It's definitely not a stranded fiber
> as is some other stock that I have.  Anyone have any ideas on what this
> substrate is?
>
> I want to get some more of this, or similar board, and am planning to
> cut it into very small sizes.  It looks like .062 single sided board
> would work for me and be relatively easy to cut.  I plan to cut using
> either my small hobby table saw with suitable blade or possibly my band
> saw with metal cutting blade.
>
> Easy (relatively) cutting is my main objectives, other structural and
> electrical properties are not critical for my needs.  Any help in
> determining the best material for my needs is appreciated.

I use CEM-1 pre-coated board. It's easy to cut it by scoring it on both 
sides with a Stanley knife and snapping it.

Leon
--
Leon Heller
Amateur radio call-sign G1HSM
Yaesu FT-817ND transceiver
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller

Thanks Leon.

 

I'm new to PC board talk .is CEM -1 a resin/paper composite .or something
similar.  I don't believe I want stranded fiberglass filler.  I'm actually
going to cut into thin (1/8" or so) strips and then cross cut to use as
intermediate cross ties to facilitate hand laying model railroad track (rail
would be soldered to a PC board crosstie every six inches or so).  The
remaining ties would be wood.  After painting and weathering, the PC ties
blend in with the remaining scenery.

 

I've currently got some strip that was cut, maybe sheared, by someone else
and the edges are not very clean.  Under magnification it is definitely some
kind of stranded (I assumed fiberglass) laminate.  I have some precut PC
ties that another supplier provided and it has very smooth white edges.  I
assume it was machine cut with a diamond wet saw or something.  Anyway, I
was hoping to learn what that substrate is (CEM-1, FR4, etc.) .maybe someone
on this list can set me straight.  I'm trying to learn as I'd like to be
able to cut my own and want to purchase the right stock when I do.  I'll
post a pic in the photo section under "Sam's track" so maybe someone can
identify visually.

 

Anyway, hope my use of the material is not considered heresy by the group .I
see it as creating more demand to keep prices down! :-)

 

BTW - We model rails do occasionally come up with some electronic circuitry
to control our trains, crossing signals, and other related electronic items
that require custom etched boards and do dabble in this from time to time as
well.

 

Thanks again for any and all help!

 

Sam



[Non-text portions of this message have been removed]

Hi Sam,

It sounds like you're describing CEM-1.  This is a paper epoxy 
material that's not suitable for THP (Through Hole Plating), so 
you'll only find it in single sided.  A common thickness is 0.0625.

The preferred way to cut PCB material is with a shear.  When I cut 
CEM-1, I don't get the smooth edges you're looking for.

If you're in the US, I can cut material for you as long as it's 
under 8" wide.  You'll have to dress the edges...

CEM-1 material is cheaper than FR-4.  I buy most of my material from 
Bill; he sells on eBay as abcfab.  If you do an off eBay 
transaction, give me the referral.

HTH,
Dennis

--- In Homebrew_PCBs@yahoogroups.com, "Sam & Paige Fell" 
<spfell@...> wrote:
>
> Thanks Leon.
> 
>  
> 
> I'm new to PC board talk .is CEM -1 a resin/paper composite .or 
something
> similar.  I don't believe I want stranded fiberglass filler.  I'm 
actually
> going to cut into thin (1/8" or so) strips and then cross cut to 
use as
> intermediate cross ties to facilitate hand laying model railroad 
track (rail
> would be soldered to a PC board crosstie every six inches or so).  
The
> remaining ties would be wood.  After painting and weathering, the 
PC ties
> blend in with the remaining scenery.
> 
>  
> 
> I've currently got some strip that was cut, maybe sheared, by 
someone else
> and the edges are not very clean.  Under magnification it is 
definitely some
> kind of stranded (I assumed fiberglass) laminate.  I have some 
precut PC
> ties that another supplier provided and it has very smooth white 
edges.  I
> assume it was machine cut with a diamond wet saw or something.  
Anyway, I
> was hoping to learn what that substrate is (CEM-1, FR4, 
etc.) .maybe someone
> on this list can set me straight.  I'm trying to learn as I'd like 
to be
> able to cut my own and want to purchase the right stock when I 
do.  I'll
> post a pic in the photo section under "Sam's track" so maybe 
someone can
> identify visually.
> 
>  
> 
> Anyway, hope my use of the material is not considered heresy by 
the group .I
> see it as creating more demand to keep prices down! :-)
> 
>  
> 
> BTW - We model rails do occasionally come up with some electronic 
circuitry
> to control our trains, crossing signals, and other related 
electronic items
> that require custom etched boards and do dabble in this from time 
to time as

> well.
> 
>  
> 
> Thanks again for any and all help!
> 
>  
> 
> Sam
> 
> 
> 
> [Non-text portions of this message have been removed]
>

--- In Homebrew_PCBs@yahoogroups.com, "dl5012" <dl5012@...> wrote:
>
> Hi Sam,
> 
> It sounds like you're describing CEM-1.  This is a paper epoxy 
> material that's not suitable for THP (Through Hole Plating), so 
> you'll only find it in single sided.  A common thickness is 0.0625.
> 
> The preferred way to cut PCB material is with a shear.  When I cut 
> CEM-1, I don't get the smooth edges you're looking for.
> 
> If you're in the US, I can cut material for you as long as it's 
> under 8" wide.  You'll have to dress the edges...
> 
> CEM-1 material is cheaper than FR-4.  I buy most of my material 
from 
> Bill; he sells on eBay as abcfab.  If you do an off eBay 
> transaction, give me the referral.
> 
> HTH,
> Dennis
> 

Thanks for the feedback Dennis.  I was going to ask if you checked my 
photos but it looks like the moderator has not approved them for 
posting yet.  I'm hoping if someone can see the material they can 
confirm the substrate type ...but sounds like your pretty confident 
what I'm looking for is CEM-1.

I actually prefer single sided and .0625 is perfect for my uses.  Why 
do you say shearing is preferred ...to reduce waste and dust?  I was 
leaning to machine cut so I won't have to dress edges ...that is not 
a plus for me.  I'm thinking a small wet saw would solve the dust 
issue if a small enough blade kerf is available ...haven't checked 
that out yet!  Otherwise I'd be making as much waste as strip.

Thanks for your offer to cut ...I'll keep that in mind.

Sam

Hi Sam,

I'll post a picture of some CEM-1 this weekend.

I find the shear more convenient than any other method I've tried 
(power mitre saw, snips, utility knife, jig saw, sears 
handicutter).  My small shear has a guide, so edges are straight and 
true, and you're right - there's no waste.

If you send me your mailing address off list, I'll send you a couple 
strips (tell me what width you want).

Regards,
Dennis


--- In Homebrew_PCBs@yahoogroups.com, "lnrrfan" <spfell@...> wrote:
>
> Thanks for the feedback Dennis.  I was going to ask if you checked 
my 
> photos but it looks like the moderator has not approved them for 
> posting yet.  I'm hoping if someone can see the material they can 
> confirm the substrate type ...but sounds like your pretty 
confident 
> what I'm looking for is CEM-1.
> 
> I actually prefer single sided and .0625 is perfect for my uses.  
Why 
> do you say shearing is preferred ...to reduce waste and dust?  I 
was 
> leaning to machine cut so I won't have to dress edges ...that is 
not 

> a plus for me.  I'm thinking a small wet saw would solve the dust 
> issue if a small enough blade kerf is available ...haven't checked 
> that out yet!  Otherwise I'd be making as much waste as strip.
> 
> Thanks for your offer to cut ...I'll keep that in mind.
> 
> Sam
>