DIY Frame painting- any tips?
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Cloverleaf
Retro Guru
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All this talk of flame and fire pits to burn paint of fills me with fear; so much risk to the strength of the frame, especially aluminium. Yes PC uses heat but most modern powders are pretty low temperature relatively, and the heat is applied evenly.
I've got a lot of powdercoaters near me but most are pretty rubbish. The wheel specialists are either expensive and rubbish or at best mediocre, and don't do anything but wheels. One of them is a local drug dealer who uses the business as a cash front. If people are going down the PC route then finding out who the local motorcycle builders use help you find the good ones. I've got a place doing my old 222 frame who seem reasonable but I'll reserve judgement for when I pick it up; it's taken them several weeks longer than promised and they've already had to redo the rear end as they'd damaged the finish the first time.
I've got a lot of powdercoaters near me but most are pretty rubbish. The wheel specialists are either expensive and rubbish or at best mediocre, and don't do anything but wheels. One of them is a local drug dealer who uses the business as a cash front. If people are going down the PC route then finding out who the local motorcycle builders use help you find the good ones. I've got a place doing my old 222 frame who seem reasonable but I'll reserve judgement for when I pick it up; it's taken them several weeks longer than promised and they've already had to redo the rear end as they'd damaged the finish the first time.
LondonClassic
Retro Guru
I did a DIY respray last summer on a steel frame. Heres what I researched and learned (credit to @allenh for the great thread on this).
I was advised against sandblasting old paint off - it can perforate thin steel tubes and is better suited to thicker guage metal.
I went for cheap and cheerful no nonsense screwfix paint stripper. All paint stripper bar very expensive trade / aerospace strippers are way less strippy than they used to be so you need to be patient and blob on several coats. Having the metal hot amps the effectiveness of the paint stripper - as does blobbing in on and then putting a thin sheet of polythene on top and forcing the stripper to sweat into the paint and not evaporate.Using this method I was able to soften most of the paint in one round.
Next is scraping - the soft paint should now come off in strips with a scraper. Not all of it though and the fiddly bits...well you need to go to the next stage.
Back to screwfix and some wire brush fittings for a drill. Hit the bits that didn't shift with stripper or just flay off bits you can't be bothered to scrape. Good for getting around the BB and lugs on a steel frame. This should get you to bare metal.
Clean the frame like a nutcase. Used three cans of brake cleaner but acetone or isopropol is also good if you have it.
Now its bare metal, best be getting some primer on sharpish. I used Acid 8 etch primer (2 coats).
1500 wet paper now to give the paint something to key into. If you've not got any you can go for coarser but go easy. Clean with alcohol/brake cleaner after a sanding.
Get some paint on. If you did all of the above don't mess about, get some 2K paint (avaialble in aerosol but about £20 a can). Mixed 2K is best sprayed in the first 2 hours from activation. Pay attention to dry time and when you can do a second coat. You need 2 coats minimum.
Again, fine wet sand the paint as gently as possible, clean off with alcohol etc and apply decals.
Get some 2K laquer on there to seal it all up.
Its a time consuming faff and materials probably cost me £110. But I got paint I want in a rare RAL colour and I'm happy with the job I did. You really want to be doing this when the weather is warm outside or if you're lucky indoor with the room hot. Aerosols justy won't work that well below a certain temp. As long as you are methodical and take time when you prep and then try and get the primer and paint on in a timely fashion you'll be ok. If you mess up then strip back and go again
I was advised against sandblasting old paint off - it can perforate thin steel tubes and is better suited to thicker guage metal.
I went for cheap and cheerful no nonsense screwfix paint stripper. All paint stripper bar very expensive trade / aerospace strippers are way less strippy than they used to be so you need to be patient and blob on several coats. Having the metal hot amps the effectiveness of the paint stripper - as does blobbing in on and then putting a thin sheet of polythene on top and forcing the stripper to sweat into the paint and not evaporate.Using this method I was able to soften most of the paint in one round.
Next is scraping - the soft paint should now come off in strips with a scraper. Not all of it though and the fiddly bits...well you need to go to the next stage.
Back to screwfix and some wire brush fittings for a drill. Hit the bits that didn't shift with stripper or just flay off bits you can't be bothered to scrape. Good for getting around the BB and lugs on a steel frame. This should get you to bare metal.
Clean the frame like a nutcase. Used three cans of brake cleaner but acetone or isopropol is also good if you have it.
Now its bare metal, best be getting some primer on sharpish. I used Acid 8 etch primer (2 coats).
1500 wet paper now to give the paint something to key into. If you've not got any you can go for coarser but go easy. Clean with alcohol/brake cleaner after a sanding.
Get some paint on. If you did all of the above don't mess about, get some 2K paint (avaialble in aerosol but about £20 a can). Mixed 2K is best sprayed in the first 2 hours from activation. Pay attention to dry time and when you can do a second coat. You need 2 coats minimum.
Again, fine wet sand the paint as gently as possible, clean off with alcohol etc and apply decals.
Get some 2K laquer on there to seal it all up.
Its a time consuming faff and materials probably cost me £110. But I got paint I want in a rare RAL colour and I'm happy with the job I did. You really want to be doing this when the weather is warm outside or if you're lucky indoor with the room hot. Aerosols justy won't work that well below a certain temp. As long as you are methodical and take time when you prep and then try and get the primer and paint on in a timely fashion you'll be ok. If you mess up then strip back and go again
Last edited:
Gtpulse
Dyna-Tech Fan
I’ve had some success using paint stripper then pressure washing it off. After that a brass wire brush on a drill and a smaller one on a dremel for the fiddly bits. Flapper wheel on the drill also good. After that hand sanded with wet and dry in increasing grit numbers.
An empty(ish) greenhouse with the floor dampened down to stop the dust was a good spraybooth from springtime onwards.
Some tips I’m sure I picked up on here - using a heat gun to warm the metal a tiny bit, then again on a low heat after laying some paint on. Also keeping the spray can in a jug of warm water meant a decent amount of pressure in the tin. Not all spray paint nozzles are made equal - the sort you buy mixed to a paint code from a motor factors are usually much better quality/spray pattern than the ones you buy ready mixed.
An empty(ish) greenhouse with the floor dampened down to stop the dust was a good spraybooth from springtime onwards.
Some tips I’m sure I picked up on here - using a heat gun to warm the metal a tiny bit, then again on a low heat after laying some paint on. Also keeping the spray can in a jug of warm water meant a decent amount of pressure in the tin. Not all spray paint nozzles are made equal - the sort you buy mixed to a paint code from a motor factors are usually much better quality/spray pattern than the ones you buy ready mixed.
Nabeaquam
BoTM Winner
Wire brush in a 10,000 RPM angle grinder does wonders as the brush fans out to get in pretty tight. It’s real fast removing paint and rust.
Then, where the brush won’t reach I use paint thinner and a small wire brush. Then dental picks. Then a homemade sand blaster to get all that remains. Where the cantilever meets the down tube and the rough welds where the drops are connected are impossible to clean out without a little sand blasting.
This will result in a perfect clean frame in about two hours. You might not have to use the sandblaster but you must completely get off all the little paint remover gum balls of old paint.
Wash very well with solvent. Then wipe down with Ospho, a powerful rust inhibitor. It contains phosphoric acid, will burn hands and eyes and eat concrete, so use gloves and eye protection.
The next day you can prime. Make sure all the sand blast is out from the inside of the frame.
Then, where the brush won’t reach I use paint thinner and a small wire brush. Then dental picks. Then a homemade sand blaster to get all that remains. Where the cantilever meets the down tube and the rough welds where the drops are connected are impossible to clean out without a little sand blasting.
This will result in a perfect clean frame in about two hours. You might not have to use the sandblaster but you must completely get off all the little paint remover gum balls of old paint.
Wash very well with solvent. Then wipe down with Ospho, a powerful rust inhibitor. It contains phosphoric acid, will burn hands and eyes and eat concrete, so use gloves and eye protection.
The next day you can prime. Make sure all the sand blast is out from the inside of the frame.
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argonsixar
Retro Guru
Wow, there is a load of knowledge on this site. Thanks one and all. I await the summer....
