Create Solder Paste Stencils With Cricut

by opendous

50K3915

Intro: Create Solder Paste Stencils With Cricut

NOTE:  DO NOT purchase a Cricut machine!  I have been informed (by TheGreatS) that the Cricut will no longer work with Sure-Cuts-A-Lot or Make-The-Cut as ProvoCraft are not willing to play nice with their customers.  I will attempt to get hold of another craft cutter and redo the tutorial.

Use a Cricut cutting machine and Sure-Cuts-A-Lot software to create usable solder paste stencils for electronic prototyping purposes.

The quality and precision of the resulting stencils is good enough to prototype 0805 and TQFP (0.8mm pitch) size electronic components.

If you need PCB layout software, I recommend the free and Open Source KiCAD EDA Suite.

This Instructable is based on a tutorial I originally posted at Solder Paste Stencils.

I would not recommend buying a Cricut just to create Solder Paste Stencils. If, however, you have a friend or relative who owns one, or find a Cricut on sale or at a Garage Sale, then buying Sure-Cuts-A-Lot software will turn a Cricut into a very useful device. Functionality will then be similar to something like a low-end vinyl/craft cutter such as the Craft Robo.

STEP 1: Materials and Preparation

Materials

- Cricut machine
- Sure-Cuts-A-Lot software
- Gerber Viewer software
- Transparency Film for overhead projectors which you can buy at any office supply store
- A Windows XP/Vista computer

Preparation

Your Cricut must have a specific firmware version. You can update/downgrade your firmware by downloading Cricut Desgn Studio and following the directions under Help for updating firmware. Note your firmware may already be up-to-date. See the Sure-Cuts-A-Lot FAQ for more info.

STEP 2: Preparing Your PCB Layout and Determining Dimensions

It may take some trial-and-error to create decent solder paste stencils as the Cricut is not very precise. It cuts rounded edges and ignores shapes smaller than about 18mil(0.46mm) by 50mil (1.27mm). This means you should make sure all your component pads are large than this. To make sure a pad still has enough solder paste area, make the pad longer. The KiCAD EDA Suite's PCB layout program has the ability to change all of a footprint's pads at once. Solder has this amazing property that during reflow it 'finds' metal pieces to link. As long as your PCB has precise solder resist, solder will find metal pieces to link. So don't worry about making pads too large (within reason, say +/- 20%).

You need accurate dimensions of your PCB stencil for later. Use your PCB layout software's distance tool to determine the distance between the outermost component pads. Not the size of the PCB, but the distance between outermost pad edges. In the example below, the PCB has a width of 2.3" but the edge to edge pad distance is 2.142".

In KiCAD, you can measure distances by selecting Drawings from the Layer pull-down menu and clicking the Dimensions button in the right-hand tool menu. It is the 4th button from the bottom.

STEP 3: Creating Gerber Files

Plot your PCB layout's Solder Paste stencil Gerber.

If using KiCAD, select Plot from the File menu. In the Plot Window, select SoldP_Cmp for Solder Paste Component Layer and click the Plot button.

STEP 4: Open Gerber File for Conversion

Open your Gerber file in Gerber Viewer. Select Open Layer(s) from the File menu.

STEP 5: Export Gerber File to SVG

Then export the file in SVG format. Select Export, then SVG... from the File menu.

STEP 6: Cutting Software

Import the SVG file into Sure-Cuts-A-Lot by Selecting Import SVG... from the File menu.

STEP 7: Resize the Design

Click Keep Proportions in the Properties Window and set the stencil's width to the value you noted earlier.

STEP 8: Prepare Transparency and Machine

Take a sheet of transparency film and cut it to the size of the Cricut's cutting mat. Tack the cut transparency to the cutting mat. Insert the cutting mat into the machine and press the Load Paper button.

Set the Cricut's Pressure wheel to High, the Speed wheel to High or Medium, and the cutting blade depth to 5 or 6. Detailed instructions can be found in the Cricut's manual. Some trial-and-error is required here. Speed and pressure may change the precision of the cuts, and larger cutting blade depth speeds up how quickly you will need to replace the cutting mat.

STEP 9: Cut Your Stencil

Proceed to cut the design. Select Cut Design from the Cutter menu.

15 Comments

GenAap 12 years ago

This may break some of your DIYing hearts (it did mine) but...
Quote
Provo Craft has won a law suit against Make The cut.
"Under the settlement, Make The Cut is permanently and immediately disallowed from selling software that is compatible in any way with Cricut machines. The company is also required to destroy all copies of the software’s source code.

For the existing software, Make The Cut also is required to take measures within 30 days to disable the 600 copies that were sold of the software with the cartridge back-up feature. Make The Cut is ordered to render these copies of the software completely non-functional until these users update their software to a copy that eliminates the back-up function.

Make The Cut Settles Cricut Software Lawsuit With Provo Craft

Now they have a law suit against SCAL

Provo Craft Sues Sure Cuts A Lot, Alleging Copyright Violations

End Quote
Hope this saves you from buying the software and THEN finding out it doesn't work with your Cricut.

jbreit01 9 years ago

Cricut cake works with old sure cuts a lot but you have to alter your hosts file toake sure scal doesn't send an autistic update to kill the ability of it using a Cricut

jbreit01 9 years ago

... To make sure scal doesn't send an automatic update to kill its ability to use Cricut machines.

cgifool 13 years ago

One of the first things it seems like every interested hacker asks me
about the Cricut is, "how can we get it to do PCBs?" Well, I've
finally done it!

I created a single-sided circuit design in Eagle, using 50 mil traces,
then exported just the pads and traces as a monochrome PNG file.

Next, I sprayed a coat of clear spraypaint on some single-sided 0.01"
PCB material and let it dry well. (Next time I will use two coats)

Finally, I imported my design into MTC using pixel trace and used my
scribing tool to scratch the design onto the PCB (multicut 2, pressure
high). This removed the spray paint around the edges of my traces.
After it was done, I used a toothbrush to brush the removed-paint-bits
off the board.

The scribing tool is critical to the success of this method, if you just use a normal blade, the swiveling of the blade ruins the accuracy of the output. I got a scriber from Frys, cut it down to fit inside the machine, and held it tightly in my universal pen holder made from aluminum stock on a lathe. (but, just wrapping with metal tape would probably work fine).

Finally, I etched with a few tablespoons of ferric chloride in a
double-bagged-ziplock immersed in hot water. The whole etching process
took less than ten minutes. Aside from some unwanted specks where my
one coat of spray paint was a bit light, the result looks perfect!

-David

[posted to my blog, http://everhack.blog.atxhackerspace.org]

gtoal 13 years ago

There is a third-party engraving tip available for the Cricut: http://www.youtube.com/watch?v=nxM_epJW80w

Maybe that could be used somehow in creating PCBs?

opendous 13 years ago

  That might make it easier to cut copper with a Cricut but the standard blade works decently enough with copper tape such as 3M 1125.

  The problem with the Cricut and trying to create PCBs is Cricut's over-cutting.  To make sure all traces remain intact they must be at least 50mils wide.  With that sort of trace width you are better off just breadboarding a project or soldering wires directly to components.

  Custom control software such as the FOSS libcutter might be more precise but the whole process is still too fragile and time-consuming to be worthwhile in my opinion.

a3v03v0 13 years ago

I have switched from sure-cuts-a-lot to a program called make-the-cut.

Make-the-cut is written and sold by the author who personally answers questions on the make-the-cut web site.

Free trial.

forlack 13 years ago

Hi there opendous.  I have access to a cricut, and I have an idea that is similar to this instructable.  I want to ask for your advice before I invest a weekend into the project.  Here is my thought:

Is it possible to take a pcb design and use the cricut to cut it out (cardstock lets say).  Then take the pcb template and use it to spray paint design on the copper pcb.  The paint would then be the same as a toner transfer, but it would take little time to do.  Everything else would be the same as far as etching, etc.

Does the cricut have the resolution to do this?  I dont have to do super tiny traces.  Let me know.

gmg 13 years ago

Alternate method for Eagle users, without hassle of Gerbers: export your design as a graphic file (bmp, jpeg, tiff) then bring into Sure Cuts a Lot with File> Trace Image. I've tried the Cricut with low-tack adhesive shelving paper and found it difficult to get traces much smaller than 30mil. I suspect adhesive backed vinyl (approx 3mil thickness) may give better results. As with a card stock pattern, you could affix to copper clad and mask the pads and traces with a Sharpie prior to etching. I wonder if you could use the vinyl as a resist mask: leave the pads and traces, weed out everything else and etch with the vinyl affixed to the copper...? Something to try next week.

opendous 13 years ago

  The Cricut is very imprecise and not all that useful for PCB design and fabrication except for quick prototyping of solder paste stencils for 0805 and larger pad components and RF shields in copper foil.

  I have tried just about every DIY PCB fabrication method and the most precise and dependable results are from using the Toner Transfer Method.  You can use just about any paper although be prepared for some isometric exercise if not using Toner Transfer Paper as it will require a significant amount of pressure and heat.  TT paper, TRF Film, and a laminator are a worthwhile investment if you intend to prototype PCBs often.  The biggest drawback is finding ferric chloride.

  A while ago I attempted to use a Cricut to cut a circuit out in Copper Foil and then stick it onto unclad FR4 on a suggestion from ladyada.  I almost managed to get something that works by using 50mil traces but the circuit was very delicate as the Cricut tends to overcut lines by a good 20mil.  This is not a problem when creating 1" letters but it causes circuit traces to be joined by very thin pieces of foil.  I have had it on my TODO list for a while now to improve the process but have not found the time.

  Your idea of spraying the circuit traces onto copper sounds like a good idea as the Cricut's overcutting will not have an impact.  Use the thickest traces you can (>25mil).  You will also need to find spray paint that is not susceptible to acid.  Write an Instructable if you figure out a process.  Good luck!


czyz 15 years ago

The smaller cricut (cuts up to 6"x12" material) can often be found on craigslist for around $60 used, and the "Sure Cuts A Lot" software costs around $67. For what it's worth.

opendous 15 years ago

I will try the above technique as soon as my Copper Foil arrives.

If your goal is automated PCB fabrication, check out a wax printer and this Instructable. Etching is still required though.

Thanks for the blog post. I didn't even realize the Cricut costs $400 from the official website. That is way too much. I added a note to my Instructable to only bother with this technique if you already have access to a Cricut or find a cheap one.

mycroftxxx 15 years ago

Wow. Very nice. I bet the sparkfun guys either already knew this one or are grinding their teeth at the spent money and lost time for making their stencils during their startup period. Does anyone have an idea how cheaply a competent engineering type could put together a Sparkfun or Adafruit-class electronics fab at this point? (CNC machine to carve/drill the PCB's, Cricut to make the stencils, etc...)

opendous 15 years ago

One DIY'er I am aware of who is creating a DIY CNC drilling machine is http://electronics.digitalintuition.com. There are countless others.

Milling a PCB might be too difficult and/or slow for a cheap DIY machine. Toner Transfer paper, a laser printer, an iron or laminating machine, and some etchant are a cheap and efficient way of creating prototype PCBs.

I generally send out for PCBs and then create prototypes with either stencils cut with Cricut or laser cut stencils I buy from Pololu.com. I use a cheap toaster oven for Reflow Soldering.

From experience, a small electronic prototyping fab can be had for < $500.