Homebrew PCBs

Along with my multi tank system I acquired some Mega (Seno) 600-021 
immerse tinning solution - it's  rather old but I'll try it anyway !

On the bottle it says to disolve in tap water at 50 deg C - let it
cool 
and use at room temperature. On the Mega site it says to disolve in 
distilled (rather than tap) water. Two questions:

a/ should it be distilled or tap water?

b/ what is the odd chemistry that lets it work at room  temp but not
at 
50 Deg C when increasing the temp normally speeds up chemical
reactions.


TIA

AWEM

--- In Homebrew_PCBs@yahoogroups.com, "Andrew Mawson" <andrew@m...> 
wrote:
<snip>

> a/ should it be distilled or tap water?

Several possibilities come to mind:

It's possible that your local tap water may contain minerals or 
other impurities which could prevent the resulting solution from 
working correctly. 

The working life of the solution may be extended by using distilled 
water.

> b/ what is the odd chemistry that lets it work at room  temp but 
> not at 50 Deg C when increasing the temp normally speeds up 
> chemical reactions.

If what you're dissolving is a mixture of dry chemicals, the water 
may need to be heated to get all of the components dissolved 
properly. Depending on the chemicals in the solution, its action may 
be more stable at a lower temperature.

Personally, I'd follow the manufacturer's recommendations unless I 
had some assurance that any changes weren't going to cause 
unforeseen problems. YMMV, of course.

Regards, Bob

hi,
i have done ecthing using ferrric chloride for a lot of years using tap water with good results!

Bob_xyz <bob_barr@...> wrote:
--- In Homebrew_PCBs@yahoogroups.com, "Andrew Mawson" <andrew@m...> 
wrote:
<snip>

> a/ should it be distilled or tap water?

Several possibilities come to mind:

It's possible that your local tap water may contain minerals or 
other impurities which could prevent the resulting solution from 
working correctly. 

The working life of the solution may be extended by using distilled 
water.

> b/ what is the odd chemistry that lets it work at room  temp but 
> not at 50 Deg C when increasing the temp normally speeds up 
> chemical reactions.

If what you're dissolving is a mixture of dry chemicals, the water 
may need to be heated to get all of the components dissolved 
properly. Depending on the chemicals in the solution, its action may 
be more stable at a lower temperature.

Personally, I'd follow the manufacturer's recommendations unless I 
had some assurance that any changes weren't going to cause 
unforeseen problems. YMMV, of course.

Regards, Bob





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

Hi,

Just discovered slitting/lever shears work real well for cutting.
Something like that:
<http://www.vansantent.com/images/slittingshear.gif>


I always used a handheld shear, but it was a right-handed one and awkward  
to cut along the line, and you need several cuts, which always leaves me  
with a slightly wobbly result.


Now i had this idea to try the lever shear, and it works real well after  
adjusting the distance between the blades a bit closer by shimming the  
lower blade.


i was looking out for a big shear (the kind with a long blade), but they  
are SO expensive... And i had that lever shear with only a few parts  
missing which could be fabricated.. ;-)

The 16cm blade is enough for most of my boards in one, straight go. Even  
with two cuts it will be staighter than a handheld shear.


ST

For the hobby user I find aviation-style offset angle compound tin
snips work very well.  


--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> Hi,
> 
> Just discovered slitting/lever shears work real well for cutting.
> Something like that:
> <http://www.vansantent.com/images/slittingshear.gif>
> 
> 
> I always used a handheld shear, but it was a right-handed one and
awkward  
> to cut along the line, and you need several cuts, which always
leaves me  
> with a slightly wobbly result.
> 
> 
> Now i had this idea to try the lever shear, and it works real well
after  
> adjusting the distance between the blades a bit closer by shimming
the  
> lower blade.
> 
> 
> i was looking out for a big shear (the kind with a long blade), but
they  
> are SO expensive... And i had that lever shear with only a few
parts  
> missing which could be fabricated.. ;-)
> 
> The 16cm blade is enough for most of my boards in one, straight go.
Even  

> with two cuts it will be staighter than a handheld shear.
> 
> 
> ST

I have been using my table saw to make all the bigger cuts and the 
bandsaw to make the smaller "nibble" cuts. Table saw worked good, 
band saw blade doesn't like PCB material at all - dulls very fast.

This morning I thought I would try cutting up a circuit board with 
tin snips. I only have the "aviator" style and it worked much better 
than I thought, however, making a long cut was a bitch because the 
material would not flex enough to easily slide past the jaws.

I can see where that shear would make quick work of cutting up a 
circuit board, it also looks like it would be handy for cutting up 
sheet metal for a small enclosure.

Chris




--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
<stefan_trethan@g...> wrote:
> Hi,
> 
> Just discovered slitting/lever shears work real well for cutting.
> Something like that:
> <http://www.vansantent.com/images/slittingshear.gif>
> 
> 
> I always used a handheld shear, but it was a right-handed one and 
awkward  
> to cut along the line, and you need several cuts, which always 
leaves me  
> with a slightly wobbly result.
> 
> 
> Now i had this idea to try the lever shear, and it works real well 
after  
> adjusting the distance between the blades a bit closer by shimming 
the  
> lower blade.
> 
> 
> i was looking out for a big shear (the kind with a long blade), 
but they  
> are SO expensive... And i had that lever shear with only a few 
parts  
> missing which could be fabricated.. ;-)
> 
> The 16cm blade is enough for most of my boards in one, straight 
go. Even  

> with two cuts it will be staighter than a handheld shear.
> 
> 
> ST

On Tue, 20 Sep 2005 15:24:48 +0200, bob_ledoux <bobledoux@...>  
wrote:

> For the hobby user I find aviation-style offset angle compound tin
> snips work very well.


That's probably what they are called over there.
There are a zillion types of shear, and some are much better than others  
in terms of material path/bending.
Get a left handed version if you are right handed, for cutting PCBs, or it  
is awkward to cut along the line ('cause can't see!).

I bought a cheap set of 3 shears (left, right, straight) at my tools shop  
for 10eur, but they were so crappy they were totally unuseable for PCB  
cutting. I had to return them again and stick with my old quality shears.  
You really need the type that allows a somewhat straight material path  
(maybe called offset, it is called "run through shear" here, roughly  
translated word by word).


Anyway, the lever shear is pretty cool! and i had it around for years,  
only needing a minor fix.

ST

I don't really like the dust and noise of saws, and i still need a new  
shaft for my small circular saw (10mm bore).

The only disadvantage of all shears is the edge is relatively rough, even  
some delamination with unsuitable shears.
But having used a expensive bungard shear and seen it produced a  
comparatively bad cut i'm satisfied.

My saw would produce a very clean cut with the carbide blade, but without  
a lathe i have a hard time making a new shaft.
When i have some spare money i'll get material for one, and pullies and a  
belt...

If you are using shears, and see "undercut" (the bottom layers of  
glassfiber beeing cut shorter) then there is a gap between the blades of  
your shear. Tighten the screw on handheld shears or put shims behind the  
lower blade of a lever shear.


ST


On Tue, 20 Sep 2005 15:44:00 +0200, lcdpublishing  
<lcdpublishing@...> wrote:

> I have been using my table saw to make all the bigger cuts and the
> bandsaw to make the smaller "nibble" cuts. Table saw worked good,
> band saw blade doesn't like PCB material at all - dulls very fast.
> This morning I thought I would try cutting up a circuit board with
> tin snips. I only have the "aviator" style and it worked much better
> than I thought, however, making a long cut was a bitch because the
> material would not flex enough to easily slide past the jaws.
> I can see where that shear would make quick work of cutting up a
> circuit board, it also looks like it would be handy for cutting up
> sheet metal for a small enclosure.
> Chris

The picture didn't show a clamping bar.   I find that invaluable in
getting a clean, straight and precise cut.   I'm not sure how I would
manage well with out one.  How do you keep the board from moving once
you start the cut?

Phil
--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> Hi,
> 
> Just discovered slitting/lever shears work real well for cutting.
> Something like that:
> <http://www.vansantent.com/images/slittingshear.gif>
> 
> 
> I always used a handheld shear, but it was a right-handed one and
awkward  
> to cut along the line, and you need several cuts, which always
leaves me  
> with a slightly wobbly result.
> 
> 
> Now i had this idea to try the lever shear, and it works real well
after  
> adjusting the distance between the blades a bit closer by shimming the  
> lower blade.
> 
> 
> i was looking out for a big shear (the kind with a long blade), but
they  
> are SO expensive... And i had that lever shear with only a few parts  
> missing which could be fabricated.. ;-)
> 
> The 16cm blade is enough for most of my boards in one, straight go.
Even  

> with two cuts it will be staighter than a handheld shear.
> 
> 
> ST

On Tue, 20 Sep 2005 19:59:08 +0200, Phil <phil1960us@...> wrote:

> The picture didn't show a clamping bar.   I find that invaluable in
> getting a clean, straight and precise cut.   I'm not sure how I would
> manage well with out one.  How do you keep the board from moving once
> you start the cut?
> Phil


I found, surprisingly, on the lever shear it doesn't move easily even  
without a bar.
It seems fully sufficient to hold it with the left hand when cutting.

ST

In the past I've tried tin snips, but the jigsaw with tungsten tipped 
blade is by far most useful for minimum amount of resources/space. Works 
much like your table saw, except you have to follow the line by eye.

If your band saw had same blade used in a hacksaw, then I can just image 
what it would of looked like after cutting PCB material.

For long cuts I use a in my jigsaw. For small cuts I also used to use 
the jigsaw, but since the guillotine was installed I use that. Although 
after shearing it sends fractures about 3 mm deep into the material.


lcdpublishing wrote:

> I have been using my table saw to make all the bigger cuts and the 
> bandsaw to make the smaller "nibble" cuts. Table saw worked good, 
> band saw blade doesn't like PCB material at all - dulls very fast.
> 
> This morning I thought I would try cutting up a circuit board with 
> tin snips. I only have the "aviator" style and it worked much better 
> than I thought, however, making a long cut was a bitch because the 
> material would not flex enough to easily slide past the jaws.
> 
> I can see where that shear would make quick work of cutting up a 
> circuit board, it also looks like it would be handy for cutting up 
> sheet metal for a small enclosure.
> 
> Chris

In article <dgk7mo+jbtb@...>,
   Andrew Mawson <andrew@...> wrote:
> Along with my multi tank system I acquired some Mega (Seno) 600-021 
> immerse tinning solution - it's  rather old but I'll try it anyway !

> On the bottle it says to disolve in tap water at 50 deg C - let it
> cool 
> and use at room temperature. On the Mega site it says to disolve in 
> distilled (rather than tap) water. Two questions:

> a/ should it be distilled or tap water?

I've used tap water with this, or a similar, product and it works ok but I
notice there can be a slight milkiness or precipitation when mixed up and
I wondered whether this was a reaction with chemicals in the water. It may
of course depend on the purity of your tap water and it is possible that
the salts present in "hard" water may interfere with the plating process
in some way.

Generally speaking pure water of some sort is better for making up most
chemicals

> b/ what is the odd chemistry that lets it work at room  temp but not at
> 50 Deg C when increasing the temp normally speeds up chemical reactions.

It is likely that the chemistry works adequatly at room temperature and
higher temperatures would lead to rapid and uneven deposition, possibly
with poor adhesion. You may even get decomposition rather than plating in
the presence of the copper.

I believe the chemistry involves Thiourea which is considered a health
hazard and the risks may be higher if it is warmer than neccessary.

The higher temperature is neccessary to get the stuff to dissolve properly
in a reasonably short time.

Stuart

I have a small carbide tipped blade running on an arbor (belt driven)
fix guide to table and pass board past blade, can use small household
water spray to keep dust down . Water also seems to give nice clean cut.
Philip

--- In Homebrew_PCBs@yahoogroups.com, lists <stuart.winsor.lists@d...>
wrote:
> In article <dgk7mo+jbtb@e...>,
>    Andrew Mawson <andrew@m...> wrote:
> > Along with my multi tank system I acquired some Mega (Seno) 600-021 
> > immerse tinning solution - it's  rather old but I'll try it anyway !

Some tin plating solutions have a rather short shelf-life.  Use a 
little caution if it doesn't work well.

> > On the bottle it says to disolve in tap water at 50 deg C - let it
> > cool 
> > and use at room temperature. On the Mega site it says to disolve in 
> > distilled (rather than tap) water. Two questions:
> 
> > a/ should it be distilled or tap water?

The problem with answering this question is it really depends on
the quality of your tap water.  Certain areas have tap water that 
is fairly "soft" and doesn't contain many dissolved minerals.  Other
areas have tap water that is very "hard" and contains many dissolved
minerals.  Depending upon the quantity and type of the dissolved 
minerals, the plating may or may not work.  Thus, it's safest to use
distilled water, which is of known quantity.  You could try it with
tap water, and if it works for you, that would let you save a few
pennies (US$.01) per board.

> I've used tap water with this, or a similar, product and it works ok
but I
> notice there can be a slight milkiness or precipitation when mixed
up and
> I wondered whether this was a reaction with chemicals in the water.
It may
> of course depend on the purity of your tap water and it is possible that
> the salts present in "hard" water may interfere with the plating process
> in some way.

Carbonates are rather notorious for wanting to cause percipitates.

> Generally speaking pure water of some sort is better for making up most
> chemicals

Pure water is a known quantity.  Tap water varies between different
areas, as well as during the year even within the same area.

> > b/ what is the odd chemistry that lets it work at room  temp but
not at
> > 50 Deg C when increasing the temp normally speeds up chemical
reactions.
> 
> It is likely that the chemistry works adequatly at room temperature and
> higher temperatures would lead to rapid and uneven deposition, possibly
> with poor adhesion. You may even get decomposition rather than
plating in
> the presence of the copper.
> 
> I believe the chemistry involves Thiourea which is considered a health
> hazard and the risks may be higher if it is warmer than neccessary.

There are a number of tin plating solutions available, some of which
have absolutely dangerous chemistries.  I remember using one from
about 25 years ago that was based on Sodium Cyanide, Stannous 
Chloride, and Sodium Hydroxide.  Talk about a real witch's brew!

> The higher temperature is neccessary to get the stuff to dissolve
properly
> in a reasonably short time.

Any type of plating process, whether it's electroplating or 
electroless plating is more of an art than a science (and, a black
art at that!).  

> Stuart

Dave

If You look really good, You´ll se the "clampingbar"´it´s located behind the lever...

  ----- Original Message ----- 
  From: Phil 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Tuesday, September 20, 2005 7:59 PM
  Subject: [Homebrew_PCBs] Re: cutting PCBs


  The picture didn't show a clamping bar.   I find that invaluable in
  getting a clean, straight and precise cut.   I'm not sure how I would
  manage well with out one.  How do you keep the board from moving once
  you start the cut?

  Phil
  --- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
  <stefan_trethan@g...> wrote:
  > Hi,
  > 
  > Just discovered slitting/lever shears work real well for cutting.
  > Something like that:
  > <http://www.vansantent.com/images/slittingshear.gif>
  > 
  > 
  > I always used a handheld shear, but it was a right-handed one and
  awkward  
  > to cut along the line, and you need several cuts, which always
  leaves me  
  > with a slightly wobbly result.
  > 
  > 
  > Now i had this idea to try the lever shear, and it works real well
  after  
  > adjusting the distance between the blades a bit closer by shimming the  
  > lower blade.
  > 
  > 
  > i was looking out for a big shear (the kind with a long blade), but
  they  
  > are SO expensive... And i had that lever shear with only a few parts  
  > missing which could be fabricated.. ;-)
  > 
  > The 16cm blade is enough for most of my boards in one, straight go.
  Even  
  > with two cuts it will be staighter than a handheld shear.
  > 
  > 
  > ST




  Be sure to visit the group home and check for new Links, Files, and Photos:
  http://groups.yahoo.com/group/Homebrew_PCBs

  If Files or Photos are running short of space, post them here:
  http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 



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

--- In Homebrew_PCBs@yahoogroups.com, "turbojet" <turbojet@k...> wrote:
> If You look really good, You´ll se the "clampingbar"´it´s located
behind the lever...

we must be looking at different pictures or have different ideas what
that is.  the only thing behind the lever is the arm that holds the
lever.  That doesn't provide any clamp that I can see.

Look at this for what a clamping bar is:
http://images.grizzly.com/grizzlycom/pics/jpeg288/G/G6089.jpg
note the horizontal bar in front of the blade.  It is spring loaded
and moves with the blade. It contacts the sheet being sheared before
the blade does. The spring tension holds the sheet in place as the
blade makes it cut.  It makes for a very high quality and precise cut.

On Wed, 21 Sep 2005 22:02:49 +0200, turbojet <turbojet@...>  
wrote:

> If You look really good, You�ll se the "clampingbar"�it�s located behind  
> the lever...


i have my doubts about the usefulness.
Anyway, my shear has none, and i checked again for tendency of the board  
to slide or rotate and there is none.
A clamp could easily be added, but it would obstruct vision.

ST

On Thu, 22 Sep 2005 05:17:19 +0200, Phil <phil1960us@...> wrote:

> we must be looking at different pictures or have different ideas what
> that is.  the only thing behind the lever is the arm that holds the
> lever.  That doesn't provide any clamp that I can see.


i reckon he was referring to my original link:

<http://vansantent.com/images/slittingshear.gif>

ST

You are reffering to a completely different type of equipment!

There are a clampingbar at the shear that ST showed.... 

  ----- Original Message ----- 
  From: Phil 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, September 22, 2005 5:17 AM
  Subject: [Homebrew_PCBs] Re: cutting PCBs


  --- In Homebrew_PCBs@yahoogroups.com, "turbojet" <turbojet@k...> wrote:
  > If You look really good, You´ll se the "clampingbar"´it´s located
  behind the lever...

  we must be looking at different pictures or have different ideas what
  that is.  the only thing behind the lever is the arm that holds the
  lever.  That doesn't provide any clamp that I can see.

  Look at this for what a clamping bar is:
  http://images.grizzly.com/grizzlycom/pics/jpeg288/G/G6089.jpg
  note the horizontal bar in front of the blade.  It is spring loaded
  and moves with the blade. It contacts the sheet being sheared before
  the blade does. The spring tension holds the sheet in place as the
  blade makes it cut.  It makes for a very high quality and precise cut.




  Be sure to visit the group home and check for new Links, Files, and Photos:
  http://groups.yahoo.com/group/Homebrew_PCBs

  If Files or Photos are running short of space, post them here:
  http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 



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

For cutting PCB then You don´t need the clampingbar, It´s mostly useful when cutting sheetmetal... 

  ----- Original Message ----- 
  From: Stefan Trethan 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, September 22, 2005 9:23 AM
  Subject: Re: [Homebrew_PCBs] Re: cutting PCBs


  On Wed, 21 Sep 2005 22:02:49 +0200, turbojet <turbojet@...>  
  wrote:

  > If You look really good, You´ll se the "clampingbar"´it´s located behind  
  > the lever...


  i have my doubts about the usefulness.
  Anyway, my shear has none, and i checked again for tendency of the board  
  to slide or rotate and there is none.
  A clamp could easily be added, but it would obstruct vision.

  ST


  Be sure to visit the group home and check for new Links, Files, and Photos:
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[Non-text portions of this message have been removed]

That?s right!
----- Original Message ----- 

From: "Stefan Trethan" <stefan_trethan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Thursday, September 22, 2005 9:48 AM
Subject: Re: [Homebrew_PCBs] Re: cutting PCBs


> On Thu, 22 Sep 2005 05:17:19 +0200, Phil <phil1960us@...> wrote:
>
>> we must be looking at different pictures or have different ideas what
>> that is.  the only thing behind the lever is the arm that holds the
>> lever.  That doesn't provide any clamp that I can see.
>
>
> i reckon he was referring to my original link:
>
> <http://vansantent.com/images/slittingshear.gif>
>
> ST
>
>
>
> Be sure to visit the group home and check for new Links, Files, and 
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
>
> If Files or Photos are running short of space, post them here:
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
> Yahoo! Groups Links
>
>
>
>
>
>
>

On Thu, 22 Sep 2005 10:34:23 +0200, turbojet <turbojet@...>  
wrote:

> You are reffering to a completely different type of equipment!
> There are a clampingbar at the shear that ST showed....


Maybe we can clarify the definitions.
Let's use some photos:

<http://www-me.mit.edu/Lectures/MachineTools/sheet/shear.gif>
This is what you apparently call just "shear". This is the type that often  
comes combined with a bending brake and or roller. It can be powered by  
hand, foot, air, electricity, ...

<http://www.fablamp.com/cmf-mid.jpg>
This is what you apparently call a lever shear (note that a lever shear  
(Hebelschere) in German is the next thing, not this one). It's natural  
habitat is apparenly the middle of the desert ;-)


<http://vansantent.com/images/slittingshear.gif>
This is apparently called a slitting shear, not a lever shear. This is  
what i meant.


<http://www.geodetic.com.au/images/hawml08296.jpg>
http://www.bloomertool.com/sitebuilder/images/Picture_024-250x168.jpg
These are tinsnips i think.
You'd want left cutting offset snips for PCBs if you are right handed, if  
i have decoded your nomenclature correctly (second photo). Offset because  
it doesn't require so much bending of the material and left handed so you  
can hold the shear in your right hand, and cut along the right edge whith  
the board outline visible. If you have a right handed shear (like i do)  
you either don't see the line or you must hold your arms at impossible  
angles and cut towards you.


<http://www.samstagsales.com/Gedore/gd426026t.jpg>
<http://www.bloomertool.com/sitebuilder/images/Picture_058-250x168.jpg>
This is a nibbler, a very useful too too! For cutting out indents etc..
Take note that there are closed and open nibblers, the open ones do not  
cut off the metal strip at the front, and are not really much use. The  
first image shows closed ones.

<http://www.us.trumpf-powertools.com/32.img-cust/N700-2_bluegrey2.jpg>
There's motorised nibblers too, but take care there are large differences  
in construction and application.


If you know additional names for one of the mentioned shears, or know  
another type (like what is the type with cutting wheel called??), please  
let me know.

ST

We were talking about the same picture - there is no clamping bar. 
sorry to beleager the point but it aint there.  period.  I was trying
to be polite and not disagree directly but guess that wasn't effective.

As to the usefullness of the maligned clamping bar, I've toured PCB
fabrication shops and they all used shears with a clamping mechanism
to initially cut their stock. 

I have a shear that has one and I find it very useful for both sheet
metal and PCB material.  There is a gap between the blade and the bar
that allows one to visually align the material.  Align, clamp, check
alignment, cut.  5-10 seconds.  perfect every time.  

You don't *need* anything, you can break the PCBs by karate chops or a
chain saw if you want but a shear with a clamping bar makes for a very
fast, clean and accurate cut.  I will continue to use it to great
effect.  There are many ways to cut PCB material, each to his own.

--- In Homebrew_PCBs@yahoogroups.com, "turbojet" <turbojet@k...> wrote:
> For cutting PCB then You don´t need the clampingbar, It´s mostly
useful when cutting sheetmetal... 
>   ----- Original Message ----- 
>   From: Stefan Trethan 
>   To: Homebrew_PCBs@yahoogroups.com 
>   Sent: Thursday, September 22, 2005 9:23 AM
>   Subject: Re: [Homebrew_PCBs] Re: cutting PCBs
> 
> 
>   On Wed, 21 Sep 2005 22:02:49 +0200, turbojet <turbojet@k...>  
>   wrote:
> 
>   > If You look really good, You´ll se the "clampingbar"´it´s
located behind  
>   > the lever...
> 
> 
>   i have my doubts about the usefulness.
>   Anyway, my shear has none, and i checked again for tendency of the
board  
>   to slide or rotate and there is none.
>   A clamp could easily be added, but it would obstruct vision.
> 
>   ST
> 
> 
>   Be sure to visit the group home and check for new Links, Files,
and Photos:
>   http://groups.yahoo.com/group/Homebrew_PCBs
> 
>   If Files or Photos are running short of space, post them here:
>   http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 
> 
> 
> 
>
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> 
> [Non-text portions of this message have been removed]

On Thu, 22 Sep 2005 19:55:05 +0200, Phil <phil1960us@...> wrote:

> We were talking about the same picture - there is no clamping bar.
> sorry to beleager the point but it aint there.  period.  I was trying
> to be polite and not disagree directly but guess that wasn't effective.


You are wrong. The picture:
<http://vansantent.com/images/slittingshear.gif>

Has a clamping bar, the homepage where it comes from even says so.
Just behind the lever, exactly like that other guy said.

Please consider for once you might actually be wrong.

ST

There ARE a clamping bar! 

Admit that you are wrong Mr. Phil!  

For me this topic is closed.

Have a nice day!

  ----- Original Message ----- 
  From: Phil 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, September 22, 2005 7:55 PM
  Subject: [Homebrew_PCBs] Re: cutting PCBs


  We were talking about the same picture - there is no clamping bar. 
  sorry to beleager the point but it aint there.  period.  I was trying
  to be polite and not disagree directly but guess that wasn't effective.



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