New Zealand Vintage Computer Forums

Hi i decided to pass on my knowledge in what i have learnt in rust removal and then later electro plating with nickel to help (and hope to stop the rust) in the vintage 8 bit pc's i have been doing up..

ok all the rust removal will need is a plastic bin or tub of some type, you can use a storage bin like from the ware house or a fish bin like from Bunnings or mitre-10.. just make sure there are no holes in the bins.. they need to be water tight. and also they need to hold the part you want to de-rust with at least 50mm all round of clearance you will see why soon.. one of the pictures shows and old fridge vegi bin i used for small bits..

the next thing is to get 1 to 3 metal (steel) rods or bars not stainless or galvanized as they will cause toxic gasses. and if you can as clean as possible from rust , paint and grease etc.. it will make it work better and faster.. i used some old metal tent pegs i had.. the other thing is to make sure they will sit above the water level.. else the electrolysis will eat the copper from the power leads as well and not get good contact.. i lie mine on an angle as they are long and i bent the roulds out at about 90 deg.

the next thing you will need is a power unit.. and really any dc will do. i have seen people use phone charges although on small parts.. i had a 12v 5Amp dc power brick that i used and seems to work fine..
and of cause some 12v hook up wire.

so the only other stuff we need is water (tap water) and some washing crystals or borax borax is better and you can get it from Bunnings or mitre-10. i got washing crystals from packnsave when doing the shopping..

now the fun part starts... lol time to get them hands dirty... my fish bin was and old one i had for awhile so i cleaned it out with warm water and dish wash to get any rubbish out.. (dirt , dust etc..)

then find a place you want to set it up... NOW there are some rules as the electrolysis will give off hydrogen gas.. so it needs to be in a well ventilated area as in hi enough concertation will go boom if a spark is present..

so i do mine out side and i have a cover to sit loose over tub to stop the wind putting derbies in the tank. (i have extra bars i put on corners)

now why we need the extra room around the part is that the more (positive) bars we put in, to a point. will help rust removal from the part.

in the tub i have 3 but for a wider part can do 2, also you dont have to do it all at once you can do a piece at a time and just rotate it around.. but power off when you do and make sure you dont touch the metal bars.. as that will cause a dead short.

i have found it easer to use warm water to dissolve the crystal than cold.. but cold still works just takes a little more mixing..

so you don't need to fill it to the top if your part is only about 1/2 way up.. fill it about 20mm above the parts you want to do and if you tub is too small to do it all at once you can do it in stages,

just remember to power off when you rotate it..

so the mixture i use is 1 x table spoon for 4 x liters of water.. and the thing is that this stuff never goes off you can re-use it again and again.. it's not an exact mix but works well

all you may have to do from time to time is syphon off the clear liquid and dump the sediment in the bottom of the tub..

that's why a clear tub is so cool you can see it working and see the crud in the bottom of the tub..

you should put the waste scum and detergent down the waste water drain not fresh water / storm water drains

one other thing i have found is if i put the part on a standoff from the bottom. i use some old plastics tomato clamps that you get from the 3 sided type but anything not conductive should be fine.. even plastic bottle lids but put blutack on them to hold them down..

from here if you have wired it up to the power unit plug it in and turn it on.. it may take a few seconds to see the little bubbles coming of the part..

now it's just time.. and NO you wont dissolve it into nothing as this will only transform the rust not metal and you will know when it's finished as the bubbles will have stopped.

when it's finished turn it off and remove the part and put the next one in if you have one.. i have left mine going overnight and checked in the morning to see them finished.

you will see what looks grey/black and turn yellow-ish after being out for a minute or two.. but this is just a coating from the process.

take it inside if you are allowed.. lol and give it a wash in some warm water with a scouring pad and i also use a nylon dish brush for the hard spots and mount holes..

i then pad it dry with and old cloth and put it in the oven at 100deg to dry off any water left.. just of 5 or so mins..

well that's it for now.. and I'll be doing part-2 when the nickel rods arrive to do the plating

so we have gone from this to this in 1 day (or less)

cleaning tools..

just one last this is you will notice that the rods will get crusted in grudge.. this means its working and that scum and on the rods is all the rust coming out of the part.. all i do to clean the rods is take them off (with the unit turned off) and give them a good scrub down and wash off.. if the rods are not showing clean metal use a sander/wire wheel or file to give then a clean up.. bright metal works better than part rusty