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

Tricks & Tools for Cleaning, Preparing and Painting.

Hi All,

We have seen a number of great restorations on the forum lately, some complete and some underway! There has also been some interesting information put up in the photo gallery, and elsewhere, about some of the tools, and methods our members have come up with to help with restorations.

After some recent interest in getting this information together, we have decided to start a thread to allow members to share there experiences, ideas and knowledge on painting and preparation.

Please feel free to add anything you have come up with, that would benefit a member who is trying to re-paint there machine. I know some common questions that come up are things such as the removal of old paint, cleaning bases and engines to look new, painting barrels, primers to use, and what tool can be purchased or made to help complete the task.

This will be a sticky topic, so it will always remain near the top of this forum area, so if we could try to keep this one on-topic, that would be great!

Cheers Guys, Looking forward to seeing some of the great ideas you have!

Hi to All,
I think that this will turn out to be a most informative thread. The wealth of knowledge that we have on the forum will hopefully benefit all members undertaking a restoration for the first time; it will also assist the more experienced amongst us with some new ideas.
I encourage all members to share some of your trade 'secrets' to make this much visited topic.
Many thanks to Emmo1980, Mr Davis and Bruce.

I also have a home made flywheel puller of the same type, Joe Brown made it for me. they are awesome.

To remove the scum and garbage from alloy engine casings I strip them bare and soak them in paint thinner. THIS WILL DESTROY RUBBER SEALS. once soaked I scrub them with a wire brush, and from there polish them up with green scourers and leave to dry. To remove paint I use paint stripper as well..

hi gents,my starting point is to pressure clean all parts using degreaser,parts are washed in kero( i don't have a parts washer so and old 20 litre plastic drum works well),then sand blasted to give best finish possible for alloy.
on painted parts i paint strip as much as possible,sand where i can then sand blast any hard to get paint off.then prime and sand ,paint(when weather permits in Melbourne)
i have just purchased infra red heat lamps to get thing moving a bit quicker

when i stripped my base i hit it with a wire wheel on the angle grinder, then washed all the dust off and dried it with compressed air before priming and painting.

then i spilled fuel on it the day after [knocked the drum over] and it hadnt completley dried and stupid me tried to wipe it off with a rag, that was bye bye to some of the shiny new paint not to worry though, this is my everyday mower untill i fix the PRO460 i found the other day, then my old one will cop the immaculate rebuild and live on a strip of fake grass in the house well hopefully she will let me lol

Well, most of my "restorations" are more like updates or repairs so this comment is no good for genuine restoration work. However, I have found the best paint for the bases are the HAMMER FINISH paints. They can be bought in bulk or pressure pack. "White Knight-Rust Guard" from Bunnings is not bad. Sometimes I also give them a spay of top coat clear over the colour. On the other hand I have tried some of the water based glossy paints and do not recommend them. They're too soft and scratch easily. Lastly, spraying always gives a better finish than brush.

I use 'chemtech' 'shock treatment' degreaser. Buy a 20L container for about $60. Mix it 1:1 with water in a 2L spray bottle from bunnings and use that to wash mowers. Use care, its corrosive class 8, stings on sensative skin and eyes and stuff.
It does a good job, An old tooth brush for the stubborn stuff. Some mowers you have to wash more than once, wash it with the engine cover on, then engine cover off.
Will tarnish bare aluminium. Will also strip off some paints. Bad resprays with bad paints and i had one gold low arch thats paint didnt fair too well.
Gets grime off wheels and the like. Need to use the brush to help with grime around the lower edge of the frame and also the oily greasy thick stuff.
Ive only got hose pressure, if you had a pressure washer it would do an even better job.
Got a gravel front yard, i wouldnt go washing with the stuff on the lawn even though its biodegradeable according to the lable.

Also use the same stuff to wash out foam filters. A bit of hot water in a bucket a bit of degreaser and squish away. gets them clean, even the ones where the mower has been tipped upside down and the filter full of engine oil.
Also wash up plastic covers and air filter housings in the laundry trough with it.

I have mentioned elsewhere about electrolytic rust removal. Probably a few out there who don't know about it, so just in case, heres a brief run down of how I go about it.

I use a plastic tub of a size suitable for the part to be de-rusted, from big rubbish bins, to ice-cream containers. I mix a couple of handfuls of bicarb soda into the water in the tub and make sure it is disolved well. Then hook up the POSITIVE lead from my 4 amp battery charger to the business end of an old spade - any steel will do, some use stainless steel sheet - and put this in the solution. The NEGATIVE lead is clamped to the piece to be derusted, and the whole process starts.

After a few minutes you should see very fine bubbles starting to pop on the surface of the water, and may even see minute bubbles rising from the rusty piece. I leave the piece in the solution for some hours - sometimes a couple of days, until the rust has been removed.

Then, hose it down, wipe it dry, wire brush it if needed, and either paint it or spray with a light oil - WD40 - if it is not going to be painted - you need to either of these things to prevent rust reforming.

This method won't hurt metal, works only on steel/iron, removes rust including the rust under paint (and then the paint will flake off). The soltion can be reused until it is too disgusting - lots of rusty foam will form and there will be a sludge at the bottom of the container.

Just check to make sure you have good electrical connections - usually you will see fine sparks as you connect the lead. The other method to check good connections of the lead to each piece of metal is to very briefly short across the two pieces of metal with a wire - sparksa indicate that you have good connections.

This method is great for getting into hard to reach places, loosening frozen nuts and bolts, etc. Just needs a little patience. There is a lot of onfo on the net too.

Hope this helps somebody.
Jeff

Thanks Jeff. I'll just add one warning to what you have said. This process removes steel as well as rust, so don't set up a job, start the electrolysis, then go on vacation. The rust will come off before any substantial amount of steel does, so if you are paying attention, all should be well. When you run out of rust, stop the process.

With electolysis do not put stainless steel in there, it will turn the solution toxic, I cant remember what it makes but I am sure it was chromium something. Just a prewarning thats all, I am not a greenie by any measure but I dont want to see anyone getting in trouble.

Good thoughts there Joe, safety is paramount when working with chemicals and especially with electricity (at 4 amps)....

A product I use after cleaning, sanding and general surface preparation prior to painting is a product called "Prepsol", but can be bought as a generic name of "Wax and Grease Remover", from any automotive paint supplier.

It removes all traces of the grease from your fingerprints prior to the first coat, so don't handle the item with your bare hands after cleaning with this product.
It works a treat!!

Deejay, I think, and hope, the actual current drawn would be a lot less than 4 amps - that is just the rating of the battery charger (incidentally the better 4 amp battery chargers have a thermal overload that limits their sustained output to 2.5 amps so the transformer won't burn out).

Quite small currents can cause substantial erosion. I once destroyed the bore of a near-new rifle's barrel by running electrolysis at 0.1 amps for about 15 hours. (Before someone asks, it was leaded up by using ill-fitting cast bullets, and it was alleged that the lead could be removed electrolytically.)

Thanks for the heads-up there grumpy...not possessing a battery charger, I wasn't sure how they work internally.

The usual ones just consist of a mains lead, a step-down transformer, and a half-wave rectifier in series with the transformer secondary output leads, Deejay. One of the secondary output leads will have a red clamp on the end, and the other a black clamp. Pretty high tech, huh? (A slightly better one will use a bridge rectifier and maybe a thermal interrupter on the secondary side.)

There are much better ones that have a switching supply that is Pulse Width Modulated to produce a programmed output voltage. The program senses output current and voltage and applies three charging phases, commonly called Bulk or Current Limited, Absorption or Voltage Limited, and Trickle or Float. The Current Limited phase is based on the charger's maximum continuous output current rating, the Voltage Limited phase should be determined by the type of battery you are charging, and to a lesser extent so should the Float phase. The old lead-antimony open-cell batteries liked about 14.4 Volts for the Voltage Limited phase, but that would kill a gel cell or glass mat battery, and would overheat a lead-calcium battery (about 14.1 Volts suits those). The float voltage should be 13.0-13.1 Volts for a lead-antimony battery, and something fairly similar for the other types, though I think a lead-calcium type would like about 13.3 Volts even better.

The battery chargers you can buy range from a few bucks for a simple transformer type, up to the sky's the limit for a programmed type. Of course the manufacturer's blurb wants you to think most of them are the programmed type when they actually aren't. So, to some extent you get what you pay for. Of course you still have to use some sense: if you connect a big battery charger to a small battery, the charging rate will be excessive during the Constant Current phase, which will cause overheating and plate erosion. If you set the charger for normal or car battery mode and connect it to a gel cell, it will apply too high a voltage during the Constant Voltage phase, and much the same applies to an AGM (Absorbed into Glass Mat)battery. Above all, don't fast charge any battery unless it is an emergency. After a short time the cell electrolyte temperature will rise above the maximum allowed and the plates will be eroded.

So, you may have made the right decision by not having a battery charger at all.

Thanks Grumpy for that info, seems a bit like a minefield...I'm glad I don't own one now!!

A molases bath is also a good way to de rust parts.

Mix the molases 1:1 with water in a tub. Submerge rusty bit. Rust comes off, takes time. Get dog to lick part clean.


Nah, wash it with water. Dry and paint.
Seen pictures etc in a Hot rod magazine. Think i also read something on a how to website. Looks the goods, low tech, works and non toxic.

It is a traditional trick in the antique car restoring fraternity, Bob. Enthusiasts keep a 44 gallon drum of molasses and dump rusty parts in it for long periods (months if necessary).

Hi grumpy, that trick is an oldie...I haven't heard about molasses for years...

How does it do it, I imagine it is a chemical Reaction, But what does molasses contain that reacts that way with rust?

Well for my electrolysis I actually use a chemical called Sodium Carbonate.In a 50 litre bucket of water.I do use a stainless steel anode and a car battery charger.As per a manual I have to do this procedure.With this mix some items can be done in as short as an hour.For the badly rusted items yes it can take longer.In the manual I have it suggest that use use a Stainless Steel anode for better conduction.I certainly have had no problem with it,and I would recommend it to anybody who is thinking about it.Much easier especially for those hard to reach areas.Also save a lot of sanding.I hate sanding.

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.
.


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