Stencil Fix - Simplify your PCB assembly with this 3D printable jig
HTML-код
- Опубликовано: 6 авг 2024
- Assembling PCBs as a hobbyist using stencils and solder paste can be challenging. Stencil Fix is here to simplify the step applying solder past by tightly holding the stencil in place.
CAD and STLs: github.com/scheffield/stencil...
Shout out to the two videos that motivated me to create Stencil Fix:
- • V3 Vacuum assisted sol...
- • Vacuum Stencil Bed Box...
Other Platforms
GitHub: github.com/scheffield
Thingiverse: www.thingiverse.com/scheffiel...
Instagram: / scheffield
Website: digitalme.co 
Наука
The parallel lift mechanism is a really nice touch! One thing I've recently discovered was using KiCad to design my board, and then using kikit to create a small frame around it with vcuts or mousebites. There is a plugin that allows you to automatically add mounting holes and fidicules for manufacturing. There is an option for the mounting holes tool to include the holes in the paste gerber, so it is cut out in the stencil you order. So I'm thinking a modification to speed things up even further and improve accuracy would be to create a parameterized holder where 3d printed rods are included on the part that holds the pcb, and those go through the part holding the stencil, then the stencil, so everything is perfectly aligned together!
Nice work! Really like the idea. I think you can make this vacuum adapter tight fit, just add small hole on the side of it or maybe adjustable hole to change the suction if needed
Genius. And your 35th sub! ❤️
OMG, First!!! that video is soo relatable!!!😆, thank's for the work!!!
Great design! I was just wondering if this would work for small flexible circuit boards. Also, is the board holder adjustable in size? Also, I only have small sized Kapton stencils. Thanks a lot ahead of time.
Cool!
Very cool. Could you link the top to bottom layer securely so that those springs don't go missing? Maybe thread some long bars through them which are locked to the bottom piece and put some caps on the top ends?
Also, an adjustable square jig piece would be neat, so you could just dial in a smaller size board. If you had the materials and ability, building the device into an oven would be amazing!
Very neat good job love the video!
That could work, I'll give it some thought.
Very nice build! Have you given any thought to how to mount the stencil so that it precisely aligns every time, for example if you're pasting a bunch of the same boards? Some hinge arrangement, or maybe registration pins and corresponding holes in the stencil?
I thought about it but it will take quite some finessing to get something like that build as we're talking sub mm. Boards of the same run are also not identical as there are always tolerances when it comes to cutting them out.
@@scheffield Thanks for your comments. Yes, positioning of the stencil with respect to the board does require precise positioning, to some small fraction of the size of the smallest pad (opening). So for 0.5mm pitch the openings may be 0.25mm, so you need positioning to say 0.05mm. However, I have not had trouble doing that with the taped-down scrap PCBs method (which you show at 1:00), even with 0.5mm pitch ICs. Repeatable positioning is also the premise behind the "3040 Solder Paste Printer" units on Amazon.
I find board edges are quite consistent, particularly within a single order. Some exceptions may occur for a board edge after snapping V-cuts, and sometimes mouse-bites leave some protruding frayed material that needs sanding off first.
Bottom line -- if you manage to incorporate some kind of hinged clamp or other registration feature, that would be very welcome!
@@scheffield Also, another idea to throw in for you and other viewers -- don't overlook the possibility of making some of this fixture using PCBs.
For example, the base plate with grid of holes could be designed as a PCB. Multiple PCBs could be glued or soldered together for additional rigidity (or thicker PCB specified). The additional precision of a PCB over 3D print might help features like registration pins, or a finer grid of smaller holes for better vac distribution. Also tape sticks to PCB material better, for ad hoc covering of unneeded holes. And you can put useful markings on the silkscreen. Hmmm, maybe I'll try mocking this up using some grid-of-holes style protoboards.
Amazing video and great tool! I wonder how much airflow you need to get enough suction and if the required parts could fit in the box if the case was slighty taller. just plugin USB or something and press go. I've been meaning to try my hand and some PCB design with surface mount components this might push me over the edge..
Brilliant idea. I have no idea but I will give it a good try. Would be awesome to not need the external vac.
You really don't need a lot of airflow, so long as you don't have much leakage. You also don't need that much negative pressure just to hold the stencil down flat -- you're just trying to get the stencil flat enough that when squeegee-ing the paste, it doesn't squish through the holes and slide under the stencil and make a mess. Indeed, too much suction and the suction itself sucks the paste under the stencil.
It's not super finicky, but you're generally not using anywhere close to the capability of a small vacuum cleaner. I think ideally you would like the combination of lowish suction and minimize the leakage, so that the lowish suction is focused where it's needed, holding down the stencil.
(Of course I do realize the vacuum is not sucking the stencil down -- it's permitting atmospheric pressure to hold it down 🙂 )
Great work! Do you have some tips for the 3d printing? (Layer height, number of walls, infill %)
Thanks! I'm using 4 walls, 30% infill and .2mm layer height. You want especially the lid to be sturdy so no to bend under the vacuum.
@@scheffield thanks. I will try this vaccum box, thanks for sharing!
1:17 Whats the type of this blue tape that many makers use? Is it ordinary masking tape?
It's ScotchBlue painters tape. But really any easy to remove tape works. Search for painters tape or making tape.
Will it work for any pcb size. And shape ??
It will work for anything smaller. You will need to design your own PCB holder that then slots into the place of the current one. Make sure that the stencil is still 150x150mm.
The issue I see with this is there is no way to do double sided assembly
ask for permission to download the cad sir!!!
You can print your own stencil
I had no idea. How does that work?