I made these tools to fabricate some of my own plates. These 'tools' are made using wood, some PETG bits and pieces, and a router. These made it a little easier to assemble a plate (but there's still a lot of room for improvements).
5. DIY FR4 Plate
5.1 Warning!
Warning! Due to the materials involved it is, in general, NOT a good idea to build your own plates. I would strongly suggest to buy some plates from an established vendor, rather than building these plates yourself.
Simply put: you can die. I strongly suggest to buy a plate from a known vendor and NOT make your own.
5.2 Steps
- Acquire materials
- Rougly cut FR4 to size (scoring)
- Route FR4 to size
- Glue FR4 on a metal spring steel plate (a blank)
- Press
- Cook
5.3 Materials
FR4
There are several sources. I acquired usable pieces of 30x30 cm FR4 from:
- Yeerda Home Official Store on AliExpress
- Fengling Joy Store on AliExpress
Neither shop offers AliExpress 'Choice' guarantee.
You have to decide for yourself if you trust their FR4 or not.
Steel blank
- Two Trees on AliExpress
Glue or sticker
I've tested different ways of glueing the plates, using 3M 468MP dual adhesive stickers (about euro 5 a piece), and spray glue (15 to 30 euro per can, plus shipping).
The stickers are easier to get, and good enough for our purposes. The glue might be a better solution, but it's hard to spray evenly, hard to get, and more expensive (unless you make a lot of plates). The glue also suffers from limited storage time (after a few months the glue may no longer work).
- 3M 486 on Amazon.nl
- Everglue Industrial Spray glue on Amazon.de (140 C, web style)
- Prime Fix High Temperature on Amazon.de (regular spray, trasnparant)
Temperature
The 3M 486MP stickers are rated 120 C, and can handle 175 C for short periods. With the bed maxing out at 110 C, and the 280 C or so Nozzle isolated from the sticker by the FR4 layer, this does not pose a problem (definitely not with 0.5 or thicker FR4).
Note that the rating does indicate a minimal strength at 120 C. In practice the stickers get a little softer at 75 C, but this does not affect the printing. In fact, you can use that to your advantage when 'cooking' the plate.
Some sprayed glues are rated for temperatures above that.
5.4 Scoring template
Some claim they can score (scratch) the FR4, then break it to size. Perhaps you can with a large vice ('bankschroef') but I was unable to.
If you can make it work then a souring template makes things easier, but I tried it, and it didn't work for me.
In the end I settled on simply scoring the FR4 using a steel ruler and fresh blades, and oversize them enough to be routed later.
5.5 Routing
I use a rig made of two wooden 18 mm paltes, and four pieces of PETG (screwed to one of the wooden pieces). I clamped the thin FR4 in between the two halves so I could route them, aligning the smoothest corner with the green section. (This corner stays square, no need to route it.)
The FR4 I used varied from 0.5 to 1 mm. Thinner is hard to handle and glue. Thicker might cause problems with the printer.
As personal protection I used a professional breathing mask, to keep those fibers out of my lungs, and routed the FR4 outside. If you look closely you can see I only rounded three corners, to match the blanks.
I should increase the size of my routing jig a little to match the steel blanks I use. I made mine a tad too small.
Do use personal protection against those fibers. Or better yet, buy a ready-made plate.
5.6 Assembly
I based all dimensions on the Begrint blanks that I bought on AliExpress. Note that the sizes differ from plate to plate and brand to brand, so I had to play a bit with the dimensions.
To simplify assembly I created another rig, again using a 18 mm wood plate, and some printed PETG elements printed, then scrwed on top of it. I mounted them to exactly match the blank, which meant they had to be spaced out a little.
If you zoom in, you can see the little gaps between the PETG parts.
The additional hole wasn't planned, but it made it easier to lift the combo FR4 surface + steel blank out of the rig, once assembled.
I used this rig to align the glass fiber top and the blank, but I'm not sure if this is the best way. I might want to try it with something that would allow an easier application of the sticker / glue. I don't know yet.
5.7 Pressing and cooking
It would have been great if I'd had a press, but I don't.
So what I did now was - after affixing the top layer to the metal blank - place the plate in my X1C UPSIDE DOWN and let it cook for half an hour at 100 degrees (bed temperature). After that I put it in between two wooden plates, and put a bucket filled with water on top of it.
When using translucent materials (yellow and green FR4) you can see that the sticker isn't sticking 'everywhere'. That's air in there, and that's something you actually don't want (air is a great insulator, and so is FR4, not something you want in between your 3D print and the heat bed).
Here's a final 1 mm FR4, stickered to a blank steel plate:
5.8 Aruco
For X1C users: I used the Smooth / High Temperature sticker.
5.9 Testing
Now I know that I can build my own, it's time to do some test prints, and compare them with purchased plates!
Again, I strongly suggest to buy a plate from a known vendor and NOT fabricate your own.
Make sure to read this page first.
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