Looking for manual stencil printer

[Gopher]

I watched the video on YouTube It does indeed look useless, I think they are on the right track in one aspect only, it really is the responsibility of the manufacturers of these stencils to offer a tool to use them. Perhaps not at that price however. Given you could make the X,Y theta movement on my printer out of Meccano I don't really see the excuse for any printer not to have it.

[Mike]

Have either of you seen the Eurocircuits one in the flesh? I have - and its got some major flaws! Firstly, your PCB must be panelised, even if its a large single impression per panel, as the panel border must have locating holes in specific locations with reference to the stencil. Secondly, it has NO lateral adjustment, no really. You can adjust in one axis, but it relies entirely on the locating pins/holes lining up exactly in the other axis. Even if that lines up ok, I don't hold up much hope for say a 0.4mm pitch device thats more than 100mm away from the edge of the locating holes.

I saw it today and actually seemed reasonably OK - the panel requirement isn't a big deal - the only thing you need is two 3mm holes on one edge, with 5mm stencil apertures 30mm below - the lateral spacing is flexible & defined by where the blocks are placed.
For occasions where you do need a little wiggle room, I think you could achieve this by placing a scrap stencil between the PCB blocks and the base, which can be slid slightly to move the PCB. This mode could also be used with non-tooled PCBs/stencils, using 4 plain corner blocks instead of the 2 pinned ones.

[SteveW]

Is this something that memory metal / nitinol wire would be good for?

(I also have a hell of a time tensioning stainless stencils in my little printer. It just clamps them along the edge in a rigid frame, and they go floppy pretty quickly, as is inevitable. I'd been wondering if I could build some offset / cam screws, to apply some tension, rather than rely on clamping, but, now I think of it, nitinol tension elements have charm. Ram current through them to loosen, take the current away to tighten.)

Steve

[Gopher]

Intriguing idea there be fascinated to see someone try it.

http://www.epsolutionsltd.co.uk/stock.php there's a 2nd user dispenser for sale here and an RV4s with lots of feeders I have prices but I assume I shouldn't post them as they don't list them online... who can say. Probably about what one might expect, I think you could buy them both and a similar vintage oven and have plenty of change from £20K.

[Mike]

Received the Eurocircuits printer today - will be a little while 'til I get to use it in anger.
Seems pretty solid - it's made from fairly chunky custom aluminium extrusions. Only minor complaint is there's nothing to stop the springs that hold the front stencil clamp open from pinging out, but this is easily fixed.
Frame height is adjustable for different thicknesses - pins and ledges on spacers are 0.8mm - chances are you'd need a support board for anything thinner anyway.
My idea of using non-tooled stencils or panels with four corner supports placed on a scrap stencil looks like it will work - it's possible to do small nudges by tapping on the edges - just need to cut one to the right size with a couple of holes for the front supports. 
Will report back once it gets used for a real job

[SteveW]

>(I also have a hell of a time tensioning stainless stencils in my little printer.

I've just done a run, having attacked the (stainless) stencil with a hot air gun while I was tightening it down in the frame.
!!!JOY!!!
No more flappy stencil getting pate under it. It's still tight after a day's use (8 panels. I'm slow, and they're 1200-part evil-mix panels...)

Steve

[Mike]

Having had the EC printer a while now and  used it on maybe a dozen jobs, it does work pretty well - alignment seems pretty good on PCBs up to about 250mm high - not tried bigger.

A few issues -
I needed to do a small mod to stop the stencil gripper opening springs coming out when loose (sticky tape)
The prop that holds it open can be sketchy at times.
On thin PCBs, the back edge doesn't quite go down far enough so you sometimes need to shim the supports up a bit - not looked at the exact cause of this - it cold just be that the corner supports need a slight chamfer adding.
The stencil surface sits quite deep in the frame, and as the distance between the bottom edge of the frame and the PCB tooling holes is fixed, it can be hard to maintain the right squeegee angle at the front so you sometimes need a second pass.

All in all I'd say that it is very useable, although I think a bit expensive - I'm not aware of anything out there that offers better value at the moment, and would certainly recommend it to anyone looking for a low-end printer.