Laser printer, toner overflow?

for laser printers that don't have a waste toner bottle, I'm not sure where the excess toner is meant to go, some sort of hopper that's part of the drum?

I had similar blotchy marks from my Brother laser and then realised it was only in the morning. The full sun was shining through the window directly on the laser and it was getting "extremely" hot. When not in direct sunlight it cooled sufficiently to give perfect prints.

This page says on that model the corona wire, which is what I think you are referring to, is inside the cartridge not the printer.

wnen my printer had magenta blotches everywhere, I got a new cartridge. Problem solved.

newshound presented the following explanation :

Usually the waste toner is collected in the cartridge itself, or at least I have never seen a small or desktop that does not. If they are smudging, time for a new cartridge.

Inkjet printers use a pad to collect the waste, in the base of the printer.

According to the Youtube Brother Global support video entitled

How to replace the waste toner box in Brother printer...

Hope this helps..

Ah, thanks. Do you mean that it is actually recycled, or is there a "second chamber" for it? I have some spare used cartridges so I can investigate.

This started soon after fitting a new cartridge, and the problem arises because loose toner is collecting in clumps at various locations around the working bits. It's contaminating the paper before the fuser because the paper is coming out dust-free. Some places can be cleaned easily but others are inaccessible without stripping.

The drum unit comes out with the toner cartridge, IIRC they suggest replacing that every few toner cartridges.

I've stripped commercial HP's right down in the past thanks to their excellent service manuals. The Brother looks as though it is not really meant to be substantially serviced, although you can replace boards.

Update, changing the cartridge has (more or less) fixed it. There was quite a significant volume of toner (perhaps a salt spoon) loose around the toner cartridge and drum unit. I guess the odd blotches come from loose dust that I did not manage to remove from the drum unit, hopefully this will gradually disperse. This was a GPC Image cartridge from Amazon. I wonder whether it was overfilled with toner so that the "capture" chamber became overwhelmed towards the end of life. Or perhaps the flow control arrangements were not working properly.

I've come across several. In fact, the Samsung CLP-41x I have now actually has a waste toner bottle. I've never had to change it.

On some HP printers at least, there's a second chamber.

I got an HP 2600n off Freecycle. It had a magenta cast on all the pages so they got rid of it.

On investigation, it had the original colour cartridges (all empty) and it was on its second black cartridge (not an HP part, so there was a benign error message too).

Turned out the magenta cartridge had filled its waste toner compartment. New cartridges all round, a transfer belt cleaning cycle and it worked perfectly. Only done 4500 pages since new, too.

Except that this refers to a completely different family of models (but thanks for the thought).

Brother's support is not as good as some other suppliers (but I have two of their printers and they are otherwise excellent).

The link I gave earlier was for your specific model and stepped through cleaning the corona wire.

Not applicable in this case, but that takes me back. I once started using a data logger on some instrumentation that was normally used for (sort of) one-off measurements, and because of the way I was plotting the output it became apparent that it was drifting at different rates through the day. I traced this to the sun coming into and out of clouds. Reflective foil on the window eliminated the problem completely.

It happens that newshound formulated :

There is a second separate chamber within all the carts I have seen. I doubt the toner would be fit to reuse anyway.

If you DIY fill, you have to empty waste toner chamber.

Sounds like your faulty cart was improperly refilled by the seller or whoever GPC is. They should have emptied the cart before refill but it's quicker not to & usually works ok.

NT