Eurorack – making front panels with the toner transfer method

First step is to have a readily drilled and fitting aluminium front panel. Pic shows the process of fitting, not all holes drilled yet.
First step is to have a readily drilled and fitting aluminium front panel. Pic shows the process of fitting, not al holes drilled yet.

Creating front panels with the toner transfer methode

If you start making pcbs on your own and look about it around the web you will quickly encounter the “toner transfer method”. This descibed printing the pcb-layout with a laserprinter onto somehow coated paper and ironing this printout directly onto the copperside of the unetched pcb. The heat causes the lasertoner on the paper to bake into the copper, enabling you to directly etch the pcb, without going the traditional way with uv-exposure and chemical developer. The black toner prevents the copper from being etched. After etching you can get the toner away with diluent or aceton.


Now one of the collegues describing the method also takled about making aluminium front panels with toner tranfer. Cause i am increasingly nerved by inkjetprintouts, clearcoat and expensive special adhesive transparent slides i decided to give it a try. Here i will describe my experiance making protoype front panels and the process in whole.

Drilling front panel

First you need a bare eurorack frontpanel with the right width, you get them from the electronics distributors. Drill your holes until the panel fits your jacks, pots and switches. I think its not a good idea to drill an already labeles front.

After the empty frontpanel has all its holes i scan it into a graphics program an set all the typo, graphics, logo a.s.o. I choose 300 dpi to have enough resolution. "300 dpi" menas there are 300 pixels for 1 inch of distance. You can set the dpi when scanning or scale the scan later up to 300 dpi. The scan itself is just a template, quality does not matter because you dont print it out later. You just print the letters and logos.
After the empty frontpanel has all its holes i scan it into a graphics program an set all the typo, graphics, logo a.s.o. I choose 300 dpi to have enough resolution. “300 dpi” menas there are 300 pixels for 1 inch of distance. You can set the dpi when scanning or scale the scan later up to 300 dpi. The scan itself is just a template, quality does not matter because you dont print it out later. You just print the letters and logos.

Scanning front panel

The i scan the panel to have a graphics template. If you dont have a scanner try to take a picture with a camera. If you got a zoom move away from the panel and zoom in, you will get much more parallel edges than makeing a picture in wide-angle.

To have good quality you should make the graphics 300 dpi (dots per inch). You can scan directly with 300 dpi in your scanner dialogue or scale the scan later up in your graphics program. The latter involves a quality loss but thats no problem. The scan wont be printed out, its just the template for your graphics. Make small crosses in the middle of your holes for easier later positioning.

Empty aluminium panel on the testprint
Empty aluminium panel on the testprint

Testing

It is not the badest idea to print your layout out from time to time and lay your pot-knobs and screws onto it. It is enoying to see knobs overlaying words.

Take a sheet of paper from an electronics distributor and glue it into the middle of a sheet of paper
Take a sheet of paper from an electronics distributor and glue it into the middle of a sheet of paper

Print it out

When the layout is finished you will want to print it out. You take a sheet of “special paper” (later more about what is special) and glue it in the middle of a normal A4-sheet. You just need to glue one of the smaller edges. This edge should point in the direction of your laserprinters paper entry. The “special paer” is just a sheet of coated paper. I use a shet from a big electronics distibutor, some use the paper you bake cockies on others use glossy paper or transparent slides. Just pay attention it is suitable for laserprinting and wont melt.

In your printer dialogue set quality to HIGHEST and darkness to DARKEST to get as much toner on the printout as possible.

IMPORTANT: print the layout mirrored!

Print the frontpanel text mirrored onto the paper which is glued to the white sheet
Print the frontpanel text mirrored onto the paper which is glued to the white sheet
Make the frontpanel free from fat, dirt, dust
Make the frontpanel free from fat, dirt, dust

Removing dirt and fat

Before ironing you should remove dirt, fat and dust from the aluminium panel with alcohol.

Now attach the frontpanel with the frontside onto the printout with some adhesive tape. The helping crosses come out quite helpful now
Now attach the frontpanel with the frontside onto the printout with some adhesive tape. The helping crosses come out quite helpful now

Tape panel on the printout

To prevent accidently shifting i use simple adhesive tape to attach the frontpanel to the paper. The cross markings i mentioned above will help you find the right position.

I cut away all unneeded paper and lay the frontpanel onto some cork and felt to protect the table from the heat. The panel on the pic is lying in the wrong direction, When you iron it, the paperside should look up of course
I cut away all unneeded paper and lay the frontpanel onto some cork and felt to protect the table from the heat. The panel on the pic is lying in the wrong direction, When you iron it, the paperside should look up of course

Ironing – mind the table!

Now you can iron the front with the attached printout. I set my iron to full power. Some advise less heat, i tried with the result, that i could scratch the toner from the surface after ironing. The more heat you apply, the better the toner will bake onto the frontpanel. Some collegues warn that to much heat will somehow liquify your printout killing clear outlines, i didnt encounter these problems yet.


Mind a good underlayment from corg or felt or both or something other. The heat is tremendous and will ruin any expensive table without problems. I big towel as underlayment wont do – we need some resistance to be able to pres the iron onto the panel.


I also put a cotton sheet (e.g. T-shirt) between iron and panel to protect the paper from mechanical damage and distribute heat better. Then move the iron slowly for about 2-4 Minutes with slight pressure all around the panel, rotate it until all is systematically ironed and very hot.

Turn the panel to let the paper look up and put 2-4 layers of cotton onto it. The cotton helps to ptotect the paper mechanically when you move the iron and distributes the heat
Turn the panel to let the paper look up and put 2-4 layers of cotton onto it. The cotton helps to protect the paper mechanically when you move the iron and distributes the heat
Now slowly move and rotate the fully heated iron for about 2 minutes with slight pressure on the cotton lying on the panel lying on the felt lying on the cork lying on the table. Well, whats UNDER the panel is not that important. But - it will get really hot, pay attention not to ruin grandmas mahagony table.
Now slowly move and rotate the fully heated iron for about 2 minutes with slight pressure on the cotton lying on the panel lying on the felt lying on the cork lying on the table. Well, whats UNDER the panel is not that important. But – it will get really hot, pay attention not to ruin grandmas mahagony table.
After ironing the panel let it cool down for 10 minutes before putting it in some water with a bit of detergent.
After ironing the panel let it cool down for 10 minutes before putting it in some water with a bit of detergent.

Soaking

After ironing the panel is very hot. Wait about 10 Minutes and put it in some water with some dish detergent.

After another 10 minutes - depends on the paper - you can peel and rub the paper from the front panel. The letters should be quite scratch resistant. If NOT you attached to less heat.
After another 10 minutes – depends on the paper – you can peel and rub the paper from the front panel. The letters should be quite scratch resistant. If NOT you attached to less heat. YOu can get all the toner off with aceton and start over again.

Peeling off

After another 10 minutes – you can also wait longer if you like – you can peel of the paper. The Graphics should be durable now and quite resistant to (light) fingernail scratching. Sometimes the letters look a bit gray, there might be some paper fibres baked on the toner, you can peel them off with your wetted finger.

The finished panel. It doesnt look perfect but until now considering effort, time, cost and final result, it's the labeling method i like most
The finished panel. It doesnt look perfect but until now considering effort, time, cost and final result, it’s the labeling method i like most

Finished

Not perfect but a good compromize between time and money.