PCB shears

Started by gez, January 20, 2004, 03:49:43 PM

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gez

How accurate are guillotine shears like these, will they provide a nice clean edge?

http://www.megauk.com/cgi-bin/mega/lp.pl?page=http://www.megauk.com/sundries_and_accessories.php

I tried straight edge tinsnips and they cause the edges of plastic boards to crumble.  Even if this doesn't happen they don't cut THAT straight!

I wanted to buy a little minicraft bench saw (lot cheaper than those bloody shears!) but have been told minicraft are no longer in business (no spare parts/replacement blades if I bought one!).

Anyone ever used something like the machine I've linked to?
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

gez

Bugger, link doesn't work.  You have to click on it and select 'shears' in the pull-down menu top right.
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

downweverything

what i do is just take a razor blade knife and score the board with a ruler to keep it nice and straight about 20 times on the copper side before etching.  then just break it by bending and it usually comes out a clean cut... the more you score it with the knife the cleaner it gets.  then i just sand the edges for extra smoothness.

gez

Quote from: downweverythingwhat i do is just take a razor blade knife and score the board with a ruler to keep it nice and straight about 20 times on the copper side before etching.  then just break it by bending and it usually comes out a clean cut... the more you score it with the knife the cleaner it gets.  then i just sand the edges for extra smoothness.

I used to do what you described but it was pretty wasteful, the edges crumbled on a lot of attempts.  Maybe it's the board I use?  

Nowadays I use a mitre saw (manual) but it's laborious and a lot of work tidying things up, plus some boards get damaged (maybe it's me?!).

I just want a machine to do it in a few seconds, nice straight edges and no fuss.
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

Chris R

i still use the tin snips.. but the edges don't turn out very well.. i end up sanding them down later.

Chris R

Jim Jones

Gez,

The only way I wind up being happy with mine is to cut them on a table saw.  I usually cut 1590B or BB-wide strips out of a big PCB sheet on the table saw, and then cut the strips to length using a small mitre box and handsaw.

Jim

gtrmac

I got a knife which is made for scoring brittle material like plexiglass and floor tiles. It has a carbide tip I believe. A few passes on each side with this and the board snaps cleanly. I like to avoid the dust from sawing the epoxy.

Gilles C

That's what I use at work when I need to cut pcbs and get a nice clean edge.

Except it's bigger than the one on that site...

But it could depend on the quality and thickness of the pcb you want to cut.

Gilles

R.G.

Grizzly tools; 12" bench shear, about $150. Expensive, but allows straight, clean cuts in all kinds of PCB stock up to 12" wide with an accuracy of about 0.025". I multi-upped boards with 0.05" between them and sliced them apart.

Nibblers work well, too.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

toneman

R G's right on here.

The mini sheer he refers to can also cut thin aluminum.

I've never had much trouble with glass-epoxy material.
the green stuff.  Easy to cut, drill, mill, sand, paint, etc.
Not! easy to glue.

The old "blue boards" that PAIA delivered were epoxy i think.
I used nibblers and tin-snips to cut.

Now, the hardest(literally) were the phenolic pcb material.
Usually a brownish/dark redish color.
Hard and Very brittle. Kinda like bakalite.
pcbs from Japan use these alot.
Find them in VCRs, stereos,  meters, Unameit.
Best way to cut that stuff is with a fine-toothed skill saw or
table saw.  Same sawing technique can be used for the epoxy
pcb stuff mentioned previously AWA plexiglas and polyethelene.

The tin-snips(or shears) technique will *not* work to well  on phenolic.
The material cracks in all directions, and when U get to the end
of the cut, a big piece usually chips off  :-(
A dremel with a ball mill and a straitedge can do the trick
if U are patient.
Sometimes i cut way outside my line, then sand/grind to the line
with a belt sander.
Which way do U want 2 try 4 your next stompbox project?
staytuned
Tone
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TONE to the BONE says:  If youTHINK you got a GOOD deal:  you DID!

gez

Quote from: R.G.Grizzly tools; 12" bench shear, about $150

Thanks for the replies everyone.  Does anyone have a link to the shears RG mentioned?  I Googled them and only came up with pneumatic shears.  At $150 it's cheaper for me to buy from the States than over here!
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

jsleep

QuoteThanks for the replies everyone. Does anyone have a link to the shears RG mentioned? I Googled them and only came up with pneumatic shears. At $150 it's cheaper for me to buy from the States than over here!

I doubt it, the thing weighs almost 100 pounds.  I got one on R.G.'s recommendation, it is very nice.

http://www.grizzly.com/products/item.cfm?itemnumber=G6089

looks like the price went up.

JD
For great Stompbox projects visit http://www.generalguitargadgets.com

gez

Quote from: grizzly blurbThis "little" machine has got to be the slickest sheet metal machine on the market!

Thanks J, I can see why they used inverter commas for little!  :shock:

Oh well, I might just have to fork out £150 (though this does seem obsene!) for the thing I linked to.  ESR sell them as well.
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

claydavis

I just use a dremel tool with a thin cutoff wheel, and clean up the edges with a file or emery board. It's easy, fast, and neat. Just make sure to wear a dust mask.

gez

Quote from: claydavisI just use a dremel tool with a thin cutoff wheel, and clean up the edges with a file or emery board

I've done that too in the past.  Couldn't stop the thing from jumping around so the cut wasn't very straight.  Might be better if it were in a jig or something.
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

jsleep

I might add that Grizzly is a very cool company.  The president of the company builds acoustic guitars as a hobby.  Some of his work was in the catalog and it looks unbelievable.  He supplies machinery to some big time acoustic makers like Taylor, Gibson, Goodall etc.

The catalog is a "man's man's" catalog, they got some tools in there that will grow hair on your chest just looking at the pictures!  Cool stuff!  Very high quality and industrial stuff.

JD
For great Stompbox projects visit http://www.generalguitargadgets.com

claydavis

QuoteCouldn't stop the thing from jumping around so the cut wasn't very straight.

If you make one quick, light pass (just enough to score through the copper), then make another slow pass to finish the cut, it should come out pretty straight.

gez

Quote from: claydavisIf you make one quick, light pass (just enough to score through the copper), then make another slow pass to finish the cut, it should come out pretty straight.

Thanks for the tip, I'll try this tomorrow clay.  If I still don't get on with it I think my pockets may end up £150 lighter.
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

Paul Marossy

I use something that's like a mini-hacksaw that I got at Home Depot or a Dremel Tool equipped with a thin cut-off wheel in some cases. I use a file to clean up the edges, if necessary.

ErikMiller

The size boards I make, I could use the 5" one if it were suitable. See the "sheet metal shears."

http://www.grizzly.com/catalog/2004/458.cfm?

My big issue is that it must cut cleanly, and leave both pieces intact.

I have a tablesaw and a chopsaw, but some of my boards are 1" square. Even a bandsaw would probably be overkill, and most woodworking tools leave a 1/8" or 1/16" kerf.