painting Series I - sandblasting to remove paint?

It depends on the skill of the sandblaster to a large extent. It's an aggressive process for soft metals, and I've seen panels deformed by over doing it.

Nitromors is pretty safe in my experience.

Whatever, you must use an etch primer on the bare metal before repainting.

Nick

I'd like to know about sandblasting too! Nitromors works well if you dont have that many layers, but is expensive if you have a lot of paint to remove!

Don't use any caustic soda on it as it has a nasty reaction with aluminium and may cause your landrover to become a new style firework.

Screwfix (just chosen because i have a catalog lygin around) seem to sell both a 'spot blaster' and a 'gritblaster' for £30 ish each. I presume that the difference in these is the sort of material that it blasts. Has anybody tried one of these on a landy?. Would they damage the aluminium?, and could they actually remove 10 layers of nato green & black? :)

It is possible to sandblast aluminium without damage provided you use something softer than aluminium rather than sand - I think crushed nutshells or similar is used. Never used it myself, but I suspect that while it does not damage the aluminium, it doesn't do much to paint either! JD

in article wEwnb.3658$ snipped-for-privacy@ursa-nb00s0.nbnet.nb.ca, born2run001 at snipped-for-privacy@fossgroup.com wrote on 28/10/03 17:17:

After speaking to a friend who uses a sand blaster at his works it is possable to use one on ally but not to course a grit and at a low pressure otherwiss it can deform the panel being cleaned.

From what I was told about doing the same to a series III,

Landy's aren't actually made from aluminium, but from something called birmabright. I understand it's aluminium with a thin (couple of molecules) coating of another metal (zinc?) If you are too aggressive with the stripping, you will remove this (zinc?) layer.

You can actually use different materials in a sand blaster. You should look at using something softer than what you are actually trying to clean. Apparently, a low pressure grit blaster should do the job on landrover bodywork. Glass bead may be better, but more expensive.

Best in the hands of an experienced operator anyway, and make sure you use some protective gear, as the dust can be pretty harmful if you inhale any of it.

Birmabright is an aluminium-magnesium alloy. So far as I know there isn't any surface treatment.

Nick

Indeed, but slapping on the Nitromors and then covering it with clingfilm helps a lot.

Nick

Ive never tried that. I do have a couple of rolls of pallet wrap in the garage though... wonder how much it takes to wrap a 101..

I used to be a shotblaster. Yes using a course grit will deform panels. Try using a powder instead. It works well at stripping off really thick paint and does not damage the Ali. Grit comes in various grades but for work on Landrovers a Powder blast is a must.

Any ideas about where I could buy or hire a powder blaster?

The only thing ive found so far is

Whichseems resonable at £23 (same as 1 tin of nitromors..) Would any grit blaster take powder too?, and where do you buy the powder from?

Blasting sounds like it might be a bit easier and cheaper than nitromors!

Finally, any idea what is the CFM rating of the compressor on a 101 is?. All these air tools seem to quote one.. (i'm assuming that CFM is cubic feet per minute of air or something?)

Thanks!

yes it will damage the ali, if it produces enough grit to remove the paint at a decent rate. The gentlest I have used was walnut or orange, it was specfied for engine parts we blasted for an outboard motor company, but it was a finishing meadia and it didn't cut.

grit blasting is no good, sand blasting - well ali' oxide - will not deform the panels if done very carefully, read very carfully as slow.

I have just remebered lending a spot blast gun to someone with a

57 fairlane - that's probably still in bits unfinished 20 years on- he blasted the boot, took him days and he used loads of sand..

think he means powder media, not sure what powder, bead is powder after a little while, but it's doesn't cut.

just looked and its a gun, not sure i can give you any advice on using it, I have built temporary cabinets around bike frames - from clear poly sheet- when bead blasting them, i spose you could do a similar thing with you landy..

take a lot longer than stripper, if done carefully, and it is much messier than stripper.

I had the largest hydrovane that beer could buy - several hundred cfm-, very high volume is the only way to commercialy blast. now i blast with a IR type 30 compressor - i think it's running about 25 cfm-, I use bead most of the time and just for finishing polished surfaces. but a mate tried to blast the pain of a petrol tank with ali oxide and he spent several hours doing half the tank - new ali oxide is very sharp.

stripper: I used to paint yank cars and almost everone wanted them bare metaled, for no good reson most of the time as sound 10 year old paint was a good base. I useed paint stripper, it can be a very clean job, if you follow a plan and it can be quick - best in the summer though.

Get some plastic sheet to cover the ground the car is on, black stuff farmers keep their grass in is good.

Clean the paint so the stripper can get a good bite, wire brush does this nicely. Mask all the parts that don't want stripper on them[you will have to accept a certain ammount of manual paint removal after stripping]. Avoid getting stripper on window rubbers, I usually had to pull the windows out anyway..

When anything that mustnt' have stripper on[oh and any cracks you won't be able to clean the stripper out of absolutely thourghly] is masked, paint the stipper on. Use a big brush to apply the stripper, i think the brush i use is for wallpaper paste. in the summer wrap the car in black plastic, leave in the sun for a while, the car/stripper gets hot and the stripper is much more effective.

remove the plastic.

get a scraper, remove all dings and notches from the blade, and polish the edge. get a cardboard box and scrape the stipper off into the box.

repeat as needed..

I have used an infra red panel or even space heater in the winter to warm the car prior to applying stripper. I have been known to use the space heater while the stripper is on but I wouldn't recomend it..

you will be left with some paint on the panels, you could keep going at it with stripper[ i spose wire wool while there is still stripper about would do], but it's easier to wash the car thourghly and then sand it down with a DA..

I would do a car like a mustang in an after noon.

Nitromoors is Ok but if you can get Synstrip - skinstripper- it's even better. don't stick your nose in the can and take a big nosefull, it's horrid. if you manage to find skinstripper have a bucket of water handy, it will blister the skin on your hands. I use nitromoors - or the equivalant- on bike wheels still, i usually use wire wool with it to reaaly scrub the paint off the cast alli'.

I used to have some left in a 5 litre can after doing a car..

the front wings on my landrover looked like they were alochromed. I think this is the best substrate for paint on ali', thats why it's used in the marine and aircraft industries. you can buy alochrome concentrate at a price that would make it quite feasible to use, that would be quite interesting.. does anyone on the group use alochrome, alodyne or anodyne? there are probably other names.

-- richard

Bead blasting using polymer beads is the most common form of blasting for soft metals. Just had some really hard old powder coating removed from some alloy wheels by this method with absolutely no surface damage to the metal. Only thing, as mentioned is too high a pressure can deform the thin panels.

Steve W

But i bet that didnt come with 10 layers of nato green/black on it :)

Thanks for all the info. I was assuming that blasting would be a lot quicker. looks like it might not be.

Sounds like nitromors and pallet wrap + heat might be worth a try.

Where about would i get that sort of stuff?

I think Tim used something like 8 5 litre cans of nitromors to do his

101. From what ive done so far mine is looking to go the same way!.

Why not try brake fluid - it seems to work VERY well when vandals pour it on vehicles !

Andrew

Don't you need old fashioned real brake fluid to strip paint?. The stuff i've got doesnt do much to paintwork (sat and rubbed a bit in to see and ended up with a slight matt patch).

The landrover panels i have stripped haven't been much more trouble than the cars, in fact the few army things i have done have lost big chunks of paint to the pressure washer;-)

somthing I didn't mention which works very well, suprizingly well infact, is wet blasting I have done quiet a few wheels with it. wet blasting uses a pressure washer, in my case an old hobby 88, stick the sand hose of the wetblast attachment in a bag of dry sand you have a very effective blaster that will remove paint and rust no problemo. find you local sandpit and buy the sharpest sand you can get, I get coarser then the 'sharp' sand they selln builders yards.

I haven't done body work with it but i have done petrol tanks- I only intended on blasting rusty bits but it does a fair job, probably quicker than 30 cfm of comressed air blaster will do.

blasting with a pressure pot and grit is like brushing loose cak of the surface with 1" paint brush - yes very quick; it would however destroy an ali panel. Grit would embed in the ali and ruin it and the panel would get distorted. I know someone who used a siphon blast setup and blasted cars, lots of little tricks like wood hammered into door shuts to tension the panels! it was grusome to see the cars on the stage with chunks of timber hammered into every orfice.

try it on a panel and see what you think. I would say buying that blasting gun would be worth while, blasting is a fantastic way of cleaning things. though i would still use chemical stripper on paint. by the way surfaces to be blasted have to be free of oil and grease, the grit will tend to bounce off and in corners you end up with a solid lump of wodge that you have to scrape out..

my local paint shop - CandC car colors in crawley used to stock it, they haven't had it for years.. i think the only effective one available is methylene chloride, nitromoors. looking on the net it looks like the most effective is methylene chloride, coudl be systrip was just stronger.. and i see they actually use methylene chloride in imerssion baths with heaters, take a nice warm bath, mmmm.

I know what you mean, i used to use loads and end up paddling about in it. Then i saw someone scraping it into a box, mmmm that looked sensible. Then i saw someone with a heat gun 'helping' it along on a panel - someone is going to tell me how dangerous this is. And we ended up doing it as outlined..

If you were to keep saying i like the paint and don't want to damage it, like a mantra, then 'accidentaly' spill some on the paint all the paint would fall off, maybe, probably, well maybe not!

by the way if you use a scraper you have to sharpen it and remove nicks from the blade, then remove the sharps corners, even then you need to be carfull on ali it will scratch quite deeply.

-- richard

I still use glass, I thought that was the most common finishing meadia sold. I did have walnut and orange shells or the skin. we had this for doing engine internals.

I would have thought it was not blasted of but chemicaly stripped then blasted to finish, but i just had a look and there are places that recon they can blast with non abrqasive media and leave the primer and any coatings like alochrome on! couldn't with the media i was using.. I stopped commercial blasting in 1989. I might by a bag and try it..

-- cheers richard