Color Laser Printer Resurrection

(using a self-made toner filter for vacuum cleaner)

Sorry, first the legal stuff: This is a report of how I did it (successfully). Please be aware that toner powder is considered as harmful to your health. If in doubt, please refrain from following the description below. I cannot accept neither responsibility nor liability for the information and materials contained in this report. Under no circumstances will I be held responsible or liable in any way for any claims, damages, losses, expenses, costs or liabilities whatsoever resulting from the use of the information given below.

I had a 10-year old copier/scanner/colour laser printer lying around that I wanted to resurrect primarily for its scanning features; but if it could be used as a printer, too, I wouldn't mind at all... It had not been used for some years, and it seems that it was transported several times over rather bumpy roads. Toner powder had spilled from the cartridges, making a total mess inside the printer. There even was some toner powder spilled over to the paper tray.

It still did print. However, the printouts/copies didn't come out as desired - above is a picture of how a B&W copy of a white page looked like before the cleaning.

First I thought about simply cleaning the printer with a vacuum cleaner, but then I read that toner particles are so small that they cannot be filtered out by standard vacuum cleaner bags. Instead they will be blown right through the vacuum cleaner and into the surrounding air. Since toner particles are suspected to be cancerogene I clearly cannot have that. I was warned, too, of toner particles sucked into the cleaner's motor provoking a dust explosion - and I obviously don't want to blow up my vacuum cleaner. But I still intended to clean the printer by myself. (Printer service professionals have specialized vacuum cleaners that are, you guessed it, quite expensive; buying one of these just for cleaning one single printer looks like overkill to me).

I found out that toner particles (5 to 30 µm dia.) are approximately the same size as pollen grains (10 to 100 µm dia.), and I assume that a pollen filter for automotive HVAC applications might do the job well enough. To be one step more towards the safe side anyway, I would wear a surgical mask when using the filter.

Filter element. The one I used is 250 × 180 × 35 mm:

https://www.amazon.de/gp/product/B06XSR8FGK/ref=pp...

Chipboard (must, of course, match your particular filter element); for my filter, I needed:

295 × 225 × 10 mm (2 pcs)

295 × 200 × 22 mm (2 pcs)

200 × 181 × 22 mm (2 pcs)

2 crevice nozzles matching your vacuum cleaner's hoses

Hose-and-nozzle set:

https://www.amazon.de/Menalux-9000846924-VARI06342...

Wood glue (PVAC glue)

Soft sealing tape

Some (16 or more) countersunk SPAX screws, approx. 4x30 mm

Hot-melt glue, approx. 2 sticks

Tools

- Screwdriver(s)

- Hack saw

- Table drill with a 4 mm bit and a center bit or a hole saw, diameter corresponding to your nozzles

- Hot-melt glue gun

- C-clamps

So I bought an automotive pollen filter replacement element and made a box around it from particle board. Filter and box are cheap enough, so it doesn't seem too bad that the complete assembly will be discarded once the printer has been successfully cleaned. However, please don't forget that toner particles are considered a health risk, so the filter box needs to be disposed of as combustible waste.

When planning the dimensions of my box I added 1 mm to both the filter's length and width in order to have a tiny gap around it, so that it won't fit too tightly into the box. (The resulting gap will be sealed with glue later).

I already had a small hose-and-nozzle adapter set that I use for dusting small things. It also can be used at my filter's 'input' side. One of the adapters from this set matched a leftover crevice nozzle from a former vacuum cleaner. For the 'output' side I purchased a cheap spare crevice nozzle matching the hose of my current vacuum cleaner. Before assembling the box I glued these two nozzles into holes (approx. 35 mm dia.) in two of the box boards using a hot-melt glue gun - one of them to go above, the other one below the filter's location. I made sure to tightly seal any gaps with a thread of hot-melt glue on both sides of the boards, for both airtightness and mechanical stability. I removed most of the nozzle ends that protrude into the box with a hacksaw once the glue had cooled down. Finding nozzles that match your hoses might require some searching or experimenting but should not prove to be too difficult.

Ooops - I realized just in time that it might get difficult or even impossible to insert the filter from the top or the bottom after assembling the four side panels since one of the two nozzles gets in the way. I think now that the best assembling sequence might be as follows: First attach the two front and rear panels with the nozzles to one of the side panels using standard wood glue, which results in a U-shaped assembly.

Then slide in the filter from the top. The air flow direction is indicated on the filter, so be careful to insert the filter with the correct orientation.

Only then attach the remaining side panel. Once the glue is completely dry, seal the edges between wood and filter using hot-melt glue since no air (or toner) is allowed to flow around the filter. This can of course be done only as long as the top and bottom panels are not yet attached to the box.

I attached the bottom and top panels with Spax screws and using some soft sealing tape in order to make the joints airtight. Drill 4 mm holes in the two panels for the screws. The Spax screws will then find their way into the face side of the panel/filter assembly by themselves (if you screw them in, of course).

Top and bottom panels could, of course, be glued on as well if you don't intend to open the box at a later date. In that case remember to use sufficient glue for an airtight fit. I recommend to clearly label the filter's input and output nozzle, particularly if they have the same diameter in your version.

After a thorough cleaning of the printer's innards - don't forget the imaging unit! - using my vacuum cleaner filter unit, followed by installing a new set of (recycled) toner cartridges, I'm happy to say that my printer does its job nicely, and that I'm fully satisfied with the results :-)

Please note that the toner cartridges have to be purchased and installed, of course, according to your particular printer model's specifications.

I am pretty sure that the cleaning procedure also will work with a black-and-white laser printer.

Considering that I already had a vacuum cleaner, the mini nozzle set, the required tools as well as some old vacuum cleaner spares, the total cost for my filter unit was approx. 25 CHF/Euro/$.