Solder paste stencil holder + PCB holder

thingiverse

This is a great and perfect PCB stencil holder. I had enough of messing with tape and shifting masks, so designed this PCB solder paste stencil holder. It holds the mask perfectly in place for the perfect solder paste print. After the print the mask is lifted up without shifting to vertical to allow to remove the PCB . I only used the holder with frameless PCB stencils. But it should also works for framed stencils. Just use longer M4 screws to hold it. It is important that the stencil is on the same height as the PCB top . The height of the stencil is fixed by the rod holders. With the STL this is 16.2+1.6 mm height. The 16.2mm is the height of the MDF support, and 1.6mm the PCB thickness. Other heights can be supported by putting thin shims below the rod holders. On the rear I placed a small piece of wood to holds the stencil in a more upright position. Optional. Without it, it also works. In the front there is a single screw. This one is to hold the holder horizontal if there is no stencil present in the holder. Again optional. On the left in one of the photo's is the tool I use to apply the solder paste. It is a stainless dough cutter. (search on Aliexpress). It is wide and stiff to make perfect prints. Also useful is the metal 'spoon' you see in the photo. (Aliexpress) very handy to stir and scoop the solder paste. The stencil can easy be adjusted for a perfect hole and pad allignment: just loosen the screws a bit, and move the stencil till it is perfect over the PCB holes . See picture. Then tighten the 4 screws. make a print: The solder paste needs to be on room temperature, stir paste before use. - place PCB in holder - clean & degrease PCB with alcohol - stencil down on PCB - put plenty solder paste close the stencil holder back, wider as your PCB is. - put you paste applicator in 45 to 60 degree down behind the paste. - Press applicator down and in one movement pull it toward you till you past the whole PCB. - Then I find it the easiest to scoop all the paste of the stencil with the applicator: rotate the applicator to 135 degree and scoop the paste up. - park the applicator somewhere safe - lift the stencil up gently - remove PCB with the perfect print! - repeat .... I also have included some examples of PCB holders for 1.6mm PCB: - 10x10cm - 5x10cm - 5x5cm - 6x10cm In the picture is the 6x10cm version shown. For other PCB sizes you can re-scale the 10x10cm to fit your PCB. I originally intended to screw the PCB holders down, hence the holes. But holding it in place with tape was easier and works just as well. The PCB can be removed from the holder using a thin screwdriver. Parts needed: 1x 8mm rod , 22 cm long 8x m4 nuts 4x M4 x 25mm screw 2x M3 nuts - 2x M3 x 10mm screw 2x bearing 608ZZ 8x22x7 - the standard spinner bearing 1x MDF 24x24cm 16mm thick 1x MDF 24x38cm or whatever you have. Print 2x rod holder and 2x spacer. 1x bottom and 1x top. 90 to 100% fill 0.3mm layers. NO support. I used ABS but use whatever you have. Remove support out of the various holes. The m4 nuts are pressed in the bottom of the stencil holder, and in the bottom of the knops. The m4 screw goes in the top on the knop. Screw it all the way in. The 2x m3 nuts are pressed in the side of the vertical parts of the holder. No screw/nut is needed in the center one. The bearings are pressed in the rod holders. Depending on your printer some sanding could be needed. Between the bearing and the stencil holder are the spacer rings placed. The bearing holders must be mounted without any space hard against the spacer and stencil holder. Otherwise it could shift sideways. Please let me know if it works for you. And give me some $$$ tips....That is a good incentive for me to publish more designs you like!