Panel making guide with minimal equipment (Euro/controllers/whatever)

Okay, I’ll build on this as I go, but I should get started with an outline which I’ll edit to fill later.

The panels I’m making in this guide are for a Bleached midi controller, but the same technique can be used for any other type of panel you’d like to make. You don’t need any fancy or special equipment, just patience and a bit of tolerance for boring repetition.

The technique is the good old “score and snap” method. You simply make a deep enough cut into both sides of the sheet so that it will create a stress fracture when bent, allowing you to make extremely precise panels which require minimal cleanup.

You should be able to go from this:

To this:

Equipment needed:

  • Some 2mm thick (or thinner) aluminium (I get it in A4 sheets)
  • A good quality box cutter/craft knife (I’m using an Olfa one here)
  • A machinists/carpenters/engineers square (optional, but saves time on marking out the panels
  • A decent (>1mm thick) steel ruler/straight edge
  • A couple of cheapo C clamps
  • A few small scraps of wood for clamping and a short length of 1x4 or similar
  • A centre punch (manual or auto - it doesn’t matter)
  • A drill (hand or press) with an assortment of bits. You’ll definitely need a 1mm, 2mm and 3mm bit, then you can use a step bit. A chamfer bit is nice to have, too.
  • Some 240-grit sandpaper and a maroon or green scotchbrite pad (the 460-600 grit ones)
  • A flat file for cleaning up the edges (optional - the 240-grit paper can be used instead)

PART ONE

MAKING THE PANELS

To start with, you of course need to know the dimensions of the panel you’re trying to make. For eurorack, it’ll be 128.5mm high by whatever HP width needed. Measure out the dimensions on the panel and mark either the horizontal or vertical dimension in pencil on the aluminium sheet, thinking about how to minimise waste of the sheet. Measure at both ends of the line to ensure the lines are perfectly straight.
important: you need about 3cm of material on the other side of the mark for clamping and leverage when it comes to bending and fracturing the sheet

There are two lines here - one on the far side marking the width of the Nearness panels, and one to mark the length of eurorack panels. I’ll keep the eurorack sheet for later, cutting it to the widths I need as I build stuff. The crossed out part is the waste material which I’ll also clamp my straight edge to, but I will still be able to use it for future projects.

Next, you’ll need to securely clamp your steel straight edge/ruler to the sheet just on the outside of your line, trying to position the clamps in a way which won’t get in the way of your cutting. You can use a thin rubber strip or bit of tape on the underside to prevent the edges of the straight edge marring the sheet, but as you’ll be sanding later, it doesn’t matter so much.


All clamped up and ready for cutting along one of the lines. The scrap wood distributes the clamping pressure across the ruler. Note the angle of the clamps!

Right, it’s time to get cutting! With a low angle and light pressure at first, score straight along the guide, making sure not to let the blade drift. Repeat a few times until you have an obvious groove, then start to increase the pressure. I generally cut about 30-50 times depending on how much pressure I’m applying.


cut cut cut

Once you’ve cut a decent groove, use your cutter to put a tiny mark on the ends of the lines so you can simply flip the sheet and reclamp on the opposite side. Alternatively, you can measure and draw out a line again if you want to be really careful.
Clamp down and CUT CUT CUT again.


bored yet? GET CUTTING!

You’ll end up with a nicely scored line that we’re going to snap the metal along. You need to now clamp the sheet at the edge of your workbench/table etc with the scored line directly along the edge. Clamp whichever way allows for the most leverage. Again, you need to avoid blocking the sheet, so angle the clamps away from the edges of the sheet:


ready for snapping

Grab your block of 1x4 and use it to apply very firm, even pressure along the scored line. Don’t just push down on the outside edge as you may bend the sheet before you snap it - not the end of the world, but it creates unnecessary extra work. All you need to do is to get the sheet to bend slightly along the line. Once it’s bent, bend it in the opposite direction.


the bottom of the wood isn’t as gnarly as the top!

this bent down really well


not so well in the opposite direction, but this is enough!

Repeat a few times and you’ll feel the resistance fall as the metal fatigues, until ta-da! The metal fractures along the score line, leaving you with a perfectly straight “cut” that only requires a tiny bit of filing/sanding to clean up.


This is the eurorack panel side of the sheet. I now need to go back and do the same thing for the Nearness panels


a tiny smidge over 128.5mm - a touch of sanding/filing on the rough edge and it’ll be perfect for euro blanks


*the Nearness top and bottom panels ready to be snapped *

and here they both are afterwards

PART TWO

DRILLING THE PANELS

Now you’ll need a drill template. I get this by either importing a panel PDF or PCB layout into Inkscape, then using Inkscape’s “snap to center of objects” tool to place little crosshairs at each point where I need to drill holes. Save the resulting file, then print out on a sheet of paper.


the panel blank is exactly the same size as the image in the printout, just raised height makes the perspective look a bit off. I’ve added dimensions for the holes, but this is optional.

We’ll be using the printout as a guide, so you need to cut it out, leaving tabs for you to wrap around the edges of the panels. Align the corners (I hold it up to the light to make it a bit easier) and fold over the tabs, securing them with a bit of tape. You need to get it exactly right, so spend some time repositioning the template if needed.


the cut out templates ready for taping down

and here’s one taped up and ready to go. I’ve added a layer of tape on the top, as this gives the centre punch a bit of material to dig in to when getting ready for…

Hammer time! You need to align your centre punch with the centre of each crosshair, then give it a light tap with a hammer. Don’t go too hard or you might create a huge dent, leading to inaccurate drilling later. You need just enough of a mark that the centre punch can easily be located in the same spot.
Protip: if your punch is polished/shiny, you can use the reflection of the crosshairs on the punch to check whether it’s aligned correctly.


all the holes punched and ready for drilling

Now that all your holes are punched, it’s time to break out the drill. I use a hand drill, but a drill press would be even better. Secure the panels either in a vice or clamp them down to some waste wood .
I use the jaws of my knackered old Workmate, but you simply need them secured with whatever you have.
You don’t really need it for drilling aluminium, but I always use a shot glass filled with some oil to lubricate the bits between holes. It extends the life of the bits and slightly speeds up the drilling.

Anyway, start with a 1mm bit, as it’ll allow you to get the highest accuracy. Locate the bit in the punched marks you’ve made, then drill into the sheet. 1mm bits are flimsy, so let the drill do its job - there’s no need to push down on the bit. Use a high speed if your drill has variable speed, but it doesn’t really matter much.


The shotglass full of (IIRC) spindle oil. Pretty much any light oil will work though.


The 1mm bit! Aww bless.


And here’s where you can see that the centre punch/template combo really paid off. Perfectly accurate pilot holes. Smooth sailing from here on in!

From here, you just need to expand your pilot holes. For this particular panel, I need a single 2mm hole for an LED light pipe, four 2.5mm holes for the mounting screws, and nine 7.5mm holes for the pots. I went from the 1mm bit to 2mm for all the holes, then did 2.5mm for the corner holes and 3mm for the potentiometer holes.

Try not to jump up in size by too large an amount - be conservative and you’ll save yourself woes such as the bit binding in the hole, or even worse jumping out of the hole and gashing the panel. I usually keep it at 1mm increments until I get to 3mm.

Once you’re at 3mm, you can switch to a step bit if you have one, otherwise keep going up 1mm at a time. With a step bit, you can just power through the steps until you reach your desired diameter.


I believe this was the 2.5mm bit I used for the corner holes.


And this was the 3mm bit. I tore off the paper at this point as it has no further use.


Here’s a step bit, ready for enlarging the potentiometer holes. I prefer to use normal bits until I’m able to get the first “step” of the bit into the hole - I feel it’s just more accurate this way.


You can see the first two holes have been completed, and two have been slightly drilled out. Not long now!

Once you’ve got all the holes drilled, it’s a good idea to get rid of the rough edges (“burrs”) using a chamfer bit or even the step bit - have the drill running and just very lightly kiss the surface of the hole with the chamfer/step bit. Check to see you’ve deburred the holes. If not, do a bit more, taking care not to expand the hole, although it’s not really too big of a deal if you do.


Here, I’m checking hole alignment with the pcb. Those tiny white marks are the centre points of the potentiometer footprints on the PCB, so we’re pretty much perfect!

PART THREE

SANDING AND FINISHING

Aaaaaaaaaalright then. I managed to lose my photos from the original run, so I’m using a panel I knocked up today. This monstrosity:


Covered in scratches! Inscrutable hole placement! 12HP of scuzz. Let’s make it pretty.

Okay, your first task will be to get rid of those surface scratches. For this you’ll need 120 and/or 240 grit sandpaper, a sanding block of some description (I use one of the pieces of wood which was used earlier), some double-sided tape (or normal tape made into loops approximating double-sided tape) and a strip of wood to act as a guide for the sanding. You’ll also need either a couple of bits of thick (<2mm) cardboard or some leftover bits from the alu sheet. These are going to prevent you from marring your work surface with the sandpaper.


Here’s the scrap of 1x4 I’m using as a sanding guide. You can use anything that’s stiff and straight, but know that it’s going to get scuffed up.

Get your thick card or alu scraps and arrange them so that they’re on either side of your panel, with a small gap (1mm or so) between the pieces. With the panel FACE DOWN you need to attach the double-sided tape in long strips in the direction that you’re planning to sand the panel. This will minimise the chances of the panel slipping or moving while being sanded.


Some strips of double-sided tape attached to the panel and two offcuts that I keep around for this purpose. Thick card will suffice, though. Note the small gap between the panel and the offcuts. This helps you get even sanding coverage. Probably not needed if you use card, though.

Peel off the backing of the tape and stick the panels down about 5cm away from the strip of wood, making sure the panel is relatively perpendicular to the wood. Saying that, you might want a diagonal brushed look, in which case do whatever angle you fancy!


All stuck down and ready to sand

It’s time to sand! Start with 120 grit if you have some deep scratches or 240 if the panel’s not too dinged up. Get enough sandpaper on your sanding block so that the entire panel will be passed over. Pushing lightly against your wood guide as you go, sand back and forth, trying not to reverse direction while the paper is on the panel. If you’re using card, this will be a bit more difficult due to the paper grabbing the card, but keep at it.


Note the length of the sandpaper is slightly longer than the panel.


*Here’s how it looks after a handful of passes. Note the areas that haven’t been touched by the paper yet. Don’t worry - you just need to keep going!


*Looking better already, but there are still some parts on the edges that haven’t been hit yet. Also, note that the areas around the drill marks are noticeably different looking. Just keep going some more!

Eventually, you’ll reach a point where the panel is uniformly sanded. It might take only a minute or two - it may take about ten minutes! If it feels like it’s taking too long, drop down a grit level and sand until you manage to get it uniform. Once it’s evenly sanded, step up through the grits until you’ve sanded the panel to 240 grit.


*240 grit done. Note there’s no rings around the drill holes any more. That means you’ve done enough!

Next up is the finishing touch - a bit of scotchbrite pad to smoothe out the harsh scratches into a softer “brushed” look. I use the maroon/oxblood one (400 grit), but the green ones (600 grit) work perfectly well if you want a more matte finish with less “tooth” to the finish. Use a bit of water to reduce clogging, and repeat the process you used with the sandpaper.

Old pad, new pad. Each pad can do a load of panels - retire them when they look as mangy as the one on the left. Saying that, I used the old pad for this panel, so I squeezed a bit more out of it!


*It’s almost there! Spritz water every now and again to prevent clogging of the scotchbrite pad.

Once you feel the panel is looking nice, reduce pressure on the panel and do twenty light passes. This will blend out any rough bits. Use a damp tissue to clean up your panel, inspect for any blemishes, and if you feel happy, that’s it!

Prise the panel from your work surface, remove the tape and wash the panel under hot soapy water. I use a bit of washing up liquid on my hands to give the panel a nice going over. Don’t use any cloths or rags - you don’t want to scratch up your nicely finished panel, do you?

If you have some acetone (nail varnish remover) or isopropyl/rubbing alcohol, you can use some on a piece of tissue paper to remove any remaining oils, sanding gunk and general nastiness. Wipe in the direction you’ve made your finish so you’re getting deep into all the cracks. Not necessary, but it ensures a spotless finish.

Now it’s time to admire your hard work:

tasty!

You can now clearcoat (matte is recommended) the panel if you want a minimal look, or if you’re like me, you’ll design a decal and go that way. That’s a whole other tutorial, though.

Well, that’s it. I hope this little guide is useful and at least shows you that making nice panels is cheap and relatively easy to do.

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20 characters of appreciation for your post :pray:

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This is a good post. It belongs in a museum! I mean, a blog, or a wiki or something?

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This post is amazing. Should we have a Tutorial category for posts like this? I could see similar posts explaining other aspects of DIY or even synthesis tutorials.

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Thanks for the nice words!
I was a bit worried upon finishing the first section that it’s a bit…unwieldy.

To the moderators; if you have any suggestions on changing the format, location etc, please let me know.

Anyway, if anyone has any questions thus far, please let me know!

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I think that would be awesome and will encourage people to do this.

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Curious as to how much money is saved buying aluminium sheet vs blank euro rack panels and drilling those?

In my case over in Japan, a huge amount - a single blank 8HP panel from 4MS is 990 yen - roughly 8 dollars.
Meanwhile, a 300x200x2mm sheet of aluminium is 740 yen - roughly 6 dollars. From that sheet, I can cut a pretty large number of 8HP plates (about 12 IIRC)
If you work out the time investment, all of this goes out of the window, of course.

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Thank you so much for making this tutorial…!

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Nice tutorial - thanks for the effort you put into this! I use a bandsaw to cut aluminum panels to size. Leaves a rough edge that has to be sanded tho.

If pot and jack holes are misaligned a bit you can file them because the nuts hide a lot of sins! Eurorack mounting holes have to be very accurate tho. A tip for aligning mounting holes is clamp a filler panel on top and drill through it as a template.

I ordered a bunch of blank 8HP FR4 panels from JLCPCB - works for most of my custom projects. FR4 is somewhat easier to work with than aluminum. The tricky mounting holes are already drilled, you can add custom silkscreen and they can be ordered prefinished in black epoxy.

I used this tool that outputs Gerbers for custom panels: https://delptronics.com/mcs-panel-maker.php

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I would definitely use a bandsaw if I could! I do all my work in my living room but sadly, the majority of apartments in Tokyo have the double whammy of thin walls and small rooms, so larger power tools are a no-no.

I started off doing FR4 panels with JLC, but the call of vintage Bang and Olufsen was too strong, so brushed aluminium won out. The JLC panel thing is much easier though, definitely!

Edit - I somehow have managed to lose my photos from the sanding part of the tutorial, so that section’s on hold for the time being. Once I’ve got some new panels to do, I’ll take some photos and finish off the tutorial.

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What kind of file would you recommend?

From personal observation: a drill in an aluminum plate can make some nasty sounds. Be sure to protect ears (and eyes, obviously).

Perfect explanation, btw!

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I use a rat tail file that tapers from 1/8 to about 5/16 inch in dia. When you put your panel over the jacks and pots it’s generally pretty obvious which holes have to be tweaked and in what direction.

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Updated with the final part - sanding and finishing!
If anyone has any questions about any of the parts, please ask!

Edit:
Finally got the decal sheet done, so this is the final product. Decal sheet > stick on panel > exacto knife/scalpel to trim the holes > clear coat (matte)

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