OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk Tricks of the Trade

For alloy parts, once stripped of all grease, gunk and garbage, I then use 'soapy' steel wool and water; working in one direction only and find it leaves a very good finish.

Working in one direction avoids scratching the surface. I don't use it on mating surfaces though.

My method/process

1) Clean oily parts with degreaser.

2) Bathe in warm caustic soda solution to remove all traces of paint.

3) Overnight electrolysis to take care of any rust.

4) High pressure hosing or a little elbow-grease with a stiff brush to scrub of oxides.

4) Gentle heating with a blow-torch prior to spraying.

5) Use good paint. I just use spray cans, but have had excellent results with Wattyl Killrust.


Craig

Okay, here I go. I'll add a few things that I find works.


Removing paint.

On broad areas of flat STEEL, I use a flap disc on an angle grinder, max of 60 grit though. then run over again with an 80 grit, then a wire cup wheel. (Be careful NOT to travel in a lateral direction because it leaves grind marks, longtitudinal or circular is the way to go, see pic, and let the disc do the work, dont apply excessive pressure). For internal corners and edges, I use a normal wire wheel on the grinder, not a cup. Then I finish off with about a 240 grit wet & dry paper. For pain in the butt internal corners, I use the Oxy/Accetylene with a neutral flame, (carburising just leaves a mess, and oxidising induces rust). Only long enough to burn the paint, not warp the steel. Then a small wire brush to clean up.
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Bolts, shafts, intricate parts made of STEEL, I find the ol' wire wheel on the bench grinder can't be beaten. Then key with 240 wet & dry. Don't hit aluminium with a wire wheel as it ruins it, gives it a streaky finish.

For brass, copper, diecast aluminum, I use scratch free scotchbrite. Steel wool or similar I find gives a really nice look, but it also gives the "over-restored" look when finished. Most times, parts made with these metals and processes were not polished when new.

For sand cast items, (rough looking finish), definately a sandblaster. But with only fine sand. Coarse sand can take too much off and ruin the look, gives a blotchy look when repainted. Caustic Soda is good too, but it's not really kosha these days, and it absolutely LOVES aluminium! Brake fluid is another good one, but it takes a while and can leave a residue in porous metal. Complicates things when it comes to repainting.


Painting.

Definately wash everything with a residue free cleaner that evaporates, Prepsol is good. Metholated Spirits is quite good too, a lot cheaper, just don't drink it! (Tastes terrible). lol. Metho is also an excellent cleaner for aluminium welding too!, neutralises oxidisation.

An etch primer is a good way to go, just make sure that it's compatible with the paint you put over it. It'll turn out rather sad looking otherwise. There are plenty of paints available these days that actually include an etch primer, "Wattyl Epoxy Enamel" is one, I use it regularly, just takes about a week to dry thoroughly. Like a rock when it does though, and fuel doesn't hurt it once it's cured properly. Fish oil is another good old trick for stopping rust, just need to get one that you can paint over, and give it plent of time to cure. Spraying is best, not brushing.

Then of course, there's 2 Pack paint for the bigger jobs. Highly toxic fumes though, and spraying it in your backyard or shed isn't really legal. But then, only if you get caught I guess! Spraying enamels are good too, but it's old technology now days, lots of paint around now thats better, unless of course you're doing a concourse restoration. Just remember, the finish you get off the gun, is what you end up with.


Preserving brass and copper from tarnish.

I often use a satin finish clear paint of good quality. Gloss can give that over-restored look again. Be sure though, NOT to use Brasso or similar first, paint hates it.


Plastics.

Depending of course on how bad it is, I use wet & dry paper. Really bad stuff needs to be evaluated, because sanding obviously removes thickness. Usually start with 600 grit, and work my way up 2000 grit. Then just good ol' kitten car polish. On clear plastics, start with 1000 grit. Car wreckers use this trick alot, even car yards. You can even forget about the polish, and use a clear gloss paint. On extremely rare pieces, you can use a fine, panel beaters finishing filler. Supercheap have it in stock. Then just go through the sanding and prep proceedures applicable.


Rubber.

I find the best for rubber that isn't perished is just steel wool. Brings it up nice and black again, and only a satin type finish. Perished rubber can be restored, for looks, by using Sikaflex. Do some practice with it first to get good at obtaining a nice streak free finish. Plenty of water and a steel scraper usually gives a good finish. You can even make new rubber seals and grommets this way, just need plenty of time and patience. If you want, you can make a mould and coat it with linseed oil. Had a mate in a car club who made all the fidly bits for an old Alvis this way.


Undoing rusted bolts.

The first thing I do is use heat. Enough to break the rust without melting the metal. Let it cool and then try it. Dont use excessive force though, if it's still stubborn, do it again. The heating and cooling is usually enough to break the hold, and sometimes loosen the bolt. Be aware though, using heat will weaken the structure of the metal. So if it's a high tension bolt, replace it with a new one.


Screws in aluminium.

Getting these pesky little suckers out can be a real pain. Usually you end up destroying the head. The best way, and it works everytime, is to use a hammer and punch directly on the top of the head, not sideways, and give it a whack. Not hard enough to damage the aluminium though. Good ol' shock treatment. Sometimes works on steel bolts too.


Taper locks.

As in ball joints or Victa boss's. I dont own one of those tapered wedge things. All I use is two large hammers. Hold one against one side, and hit the direct opposite side with the other. Might take a few hits, but it will work. Wont damage crankcase housings or flywheels either. Unless you're off target! lol


Hope all this can help someone, it works for me and I've been doing it for years. I've got 30+ years as fitter up my sleeve.

I'll put more hints up as I get the time.

Hey there everyone, I've taken up some of this advice and setup my little electrolysis tub. Mainly to remove paint from my failed engine respray. It does feel a bit like throwing a toaster in bath.

My power source is only 12V 4.8A. My understanding from this and some googling is this is on the low side, but will still work and just take longer.

I'm also starting to see what looks like a light algae swampy looking goo forming on my hunk'o'steel red connection.

I'm guessing it's starting to work, but I don't see any paint lifting yet. Does this sound right to you guys?

While on the subject of rust removal. I use washing soda (here in SA called "Electric Soda")instead of carbonate of soda (baking soda). The action is identical. The part that corrodes away is not the object you put in there to clean - but a piece of old steel connected to the positive terminal of the battery charger. This eventually decomposes and falls to the bottom of the tank. The part you are cleaning (connected to the negative terminal of the charger),is cleaned by the action of hydrogen forming under the rust or paint particles and lifting them off. Best not to be smoking when you lift off the lid. I run mine at 1 or 1.5 amps - which you can vary by shifting the positive away from the negative. This process is the safest of many ways to clean metals. I have tried both molasses and bread. Both worked - slowly, and in the case of bread - smelly. I found the paint on chemical means a bit messy. I do the rest as per Jeff49
Stationary

Just a note re Screws in aluminium as mentioned by Greg - I had trouble getting an aluminium hub cap off a steel thread on a Buick wheel once - squeezed a lemon over it a few times a week for a month. I suppose that the action of the citric acid freed up the corrosion.
Stationary

I've used several methods over the years, and often achieved bad outcomes in cases where the head of the bolt or screw was missing and the thread was locked in place over a considerable length. Here is what I consider a sensible list of approaches for cases where the situation is not too bad:
http://www.motorcycle.com/how-to/how-to-extract-stuck-screws-3440.html

In fairly extreme cases, where the screw is either heavily bottomed in the thread or is frozen along its length, and the entire head and shank of the screw or bolt are broken off below surface level, there are a couple of correspondingly extreme remedies that may be worth a try. Strange as it may seem, I've succeeded fairly often with a simple solution. I find or make a hard, sharp punch that I can apply as near as possible to the outside of the broken off end of the screw, and tap it anticlockwise with a small hammer. It usually can be made to unscrew, unless the screw or bolt has broken off a long way below surface-level. Remember, the tip of the punch has to cut into the surface of the screw or bolt, but not touch the internal thread in the mating component. I always try this method first, because the alternatives are more difficult and more likely to make the situation worse.

If that won't work, there are two other things I choose between, depending on circumstances. If the internal and external threads are not all that heavily bonded to each other (i.e. the bolt was broken off or bottomed and twisted off, rather than rusted-in), I usually drill down the center of the screw or bolt and use a stud extractor. I only use an easy-out if the screw is actually loose in the housing, because they always expand the shell of the screw and make it a lot harder to remove. Instead, I use a proper stud extractor: a very strong parallel device with a few very shallow splines down its length. These do not expand the shell of the screw much, and can deal with rather high applied torque levels.

If the internal and external threads are heavily bonded to each other by loctite or corrosion, I try the use of heat. Use a small tip on an oxy torch, and apply the tip of a neutral or reducing flame to the center of the screw (Preferably don't heat the external component: you may ruin it). Briefly heat the screw red hot and let it cool. Repeat a few times. Then proceed to try the punch solution above. If that fails, drill the screw and try the stud extractor. If that fails too, I am stuck with either drilling the whole screw out and tapping the hole oversize, or taking the component to a commercial place that removes the screw by electrical discharge erosion. This will destroy the external thread, of course, so I tend to drill it out myself and retap it, to save the cost of the spark erosion process.

Extremely good points raised by grumpy here I must say. I too, don't like the easy out tools, for the same reason. I don't own any! In my time at the Ordnance Factory here in Bendigo, we only used the disintegrating method on expensive items. Another trick I have found that sometimes works too, as long as the threaded hole isn't blind, (goes right through), is to simply use a smaller drill bit than the thread, and try drilling into it. Occasionally the force applied will sometimes break the hold and screw the remaining part through, and out the rear face. But yes, blind holes are tricky, have plenty of patience, be careful, and don't hurry the job.

Oh Yeah, another way of fixing a threaded hole where you've had to drill the old out, and now it's too big, is to drill and tap it even bigger, screw in a bung (usually a bolt) sealed with high strength loctite, then drill and tap that back to the original size. After you've cut / ground / filed the top of the bung level with the original face. Sometimes, doing this is a quicker method!

One of my sayings,
If it's dificult - it takes a while.
If it's impossible - it just takes a bit longer!

Greg, with regard to using a drill to rotate the stump of the screw clockwise and screw it right through the part, there is an exotic alternative. You can buy anticlockwise drill bits. If you are going to have to drill down the length of the screw-stump anyway, to apply a stud extractor, it makes sense to use an anticlockwise-rotating drill with an anticlockwise drill bit, because there is a fair chance it will unscrew the stump far enough to enable you to grab the end of it with vice-grips. If it doesn't, you haven't lost anything anyway except the higher cost of the anticlockwise drill bit (which is re-usable of course).

I haven't personally used anticlockwise drill bits, but they exist, and I have seen this trick advocated by experts.

They certainly do exist, I've used them many times. Obviously you need a drill that rotates in the correct direction.

Hi all, DO NOT use stainless steel as your sacrificial anode in the conductive solution, as this will produce Hexavalent chromium which is a genotoxic carcinogen. I use black 2 mm sheet steel in a 60 ltr tube with soldered 15 amp house wire conecting the anodes together, so u have wall to wall line of sight a fused charger 12/24 volt 30 amp .... Sodium Carbonate works best as the conductive solution u can find this ingredient in a product called lectic its often used as a water softner comes in crystal and powder form cheers steve.

how does this method go with rust on chrome ? a few things i have wont clean up well using normal type things , cutting compound , soft steel wool and the like . good forum this , been looking for info on the electric cleaning . thanks guys