A was for Austin, but now B is for Bedford

I stripped my old Inter back to bare metal too ......used about 1 ton of white sand........trouble is any rustproofing on the metal goes away too, the old pommy stuff was usually hot phosphated ,then chromate washed before undercoating ,which is why they last so long ..With that gone ,soon as the paint fails ,rust eats the steel away.

Never knew or thought about the steel work being treated before painting. So the alternative to stripping to bare metal is what process...... ???? to manage modern paint and old lead paint.
My very limited experience was lots of wet and dry hand sanding of a black citroen L15, which eventually became burgundy. Lots of issues with old undercoat colours showing through. (Not to mention the very amateur outdoor spray painting).

As much of a PIA it is to do as each panel is prepared back to bare metal a quality metyal primer should be applied, not an undercoat as that is very porous and lets moisture in. Phosphoric acid treatment, zinc chromate and or the good old red oxide metal primer if you can get your hands on it.
Selleys used to make a metal primer that was water based and it is no longer available and I often send an email asking when they are going to make it again as NONE of their current products would hold a candle to it. Always a no reply or it isn't viable and so on. You could brush this stuff on and get a perfect application as if it was sprayed. I did some test sections on some bed angle iron. It was very rusty from sitting outside in the very salty air at Harrington when we lived there. Some sextions were brushed straight onto the rust, some rubbed back to bare metal and some had the real smelly fish oil done in the same way, on rust and rubbed back and the paint won out even over 10 years sitting out in the open after applying the stuff. If I could buy it today I would buy a 200 litre drum of the stuff.

200 litres? You must be planning a lot of restorations.

Been following this post and similar ones for a while now and have decided to have a go myself at refurbishing the spare Karrier cab that has just arrived.
Spoken to the sandblaster already and he has given me a quote to do the bare cab with the doors removed and stripped down of all parts, along with the grille and a spare dash, virtually the complete cab.
Have to ask him to go a bit gentler with this one as the cab is in pretty good nick, unlike the last one that ended up like swiss cheese.
He sprayed it after blasting, just a coat of grey primer to stop the rust from getting in, get him to do the same again.
Little bit of rust so far in bottom of passenger's door, on the curve where the inner and outer skins are welded in.
Bit of the rain gutter about 4 inches needs attention above same door, otherwise the cab is reasonably sound.
Floor panels need replacing, but they are flat and can use old plates as templates, thought it may be worthwhile going a bit heavier in gauge for floors, as compared to 18 gauge for door skins etc.
Going to have to get fair dinkum now, ordered a heap of air/power tools for panel work, thought one of those reciprocating saws with the thin blade may be worth looking at. Have an air nibbler on its way, another die grinder, set of panel beating hammers and dolly's, got just about everything else already here, 4 and 5 inch angle grinders, Mig etc..
Never gonna learn if I don't have a go, WTF? Can only stuff it up!
Dave_64

Good on you Dave for having a go at it. Really it sounds more scarey than it really is to do. Take small steps and you will make it to the end.
Something I noticed when the mobile sand blaster did the tractor was he used different medium on the alloy parts than the steel. My guy used a what could be best described as finely crushed glass on the steel and I found it was a bit too agressive and left the surface pitted but there was no rust there before he started. I think if he used the same as he did on the alloy parts it would ahve been better but in the end the job was good enough.
If any parts need body filler on them I can suggest that you buy a long sanding board that takes different grit paper for nocking back the filler. You can knock the top off using a random orbital sander but for a straight flat finnish use the board and run it in all different directions so that the filler takes the shape of the panel. I can take a pic of mine if needed and if I was buying again would buy a longer one. Use 40 grit first then down to 100 grit and use a high fill primer over the top before undercoat. Remember that undercoats do not seal out moisture so use a good metal primer then your undercoat.
Be careful when using your hammer and dollies that you do not stretch the metal and make high spots. When learning this step it takes years to get it right so be happy with getting it close to shape then fill it, unless you are confident in trying for that metal finish.
Good luck with your project and no doubt many regulars here are happy to help with good advise.

At my present rate of progress (nothing at all this weekend!) you'll overtake me Dave_64. :oops:

This morning I intend to buy one of those whirly plastic sponge things to give that a go at the old paint later, but not sure when as I'm covering the Op Shop again this afternoon . . .

PS You lot are making me feel really guilty as your posts are out numbering mine at the moment. Keep it up, it will pressure me back into action.

Believe it or not,the finer the grit ,the more abrasive it is .....this is the only thing I learned at the sandblasters I didnt already know .......one time I did a old low loader frame ,and got bags of fine sharp gravel ,thinking it would be good on the rust ........the stuff was like being shot with a #7 barrage in a 12 ga....it all bounced back and peppered me.......Anyway ,for doing old motorbike stuff ,I found the best was the actual garnet dust from the dust collector ......very dusty tho........For doing sheet metal ,some care is needed ,as the blast can actually heat sheet metal red hot ,and burn it away.........Whats needed is around 40 to 60 psi air ,and very fine garnet........When I was there ,the fine garnet dust was dumped at some cost as industrial dust ,about $200 a ton ,but now ,the stuff is recycled for water cutting ,and is somewhat valuable .So I probably wouldnt get it free any more.

PDU, i use Smith & ARROW brand poly strip discs, usually the coarse ones though i do have some medium, and i find them very good.

I have also cut them up with a hole saw to get several small round circles of strip disc which i fastened together on a threaded rod, and used in an electric drill for cleaning internal holes. Depending on the length of threaded rod, a loose fit poly pipe "handle" over the thread makes for easy control/guidance.

Strip discs are also terrific for finding/cleaning stamped engine/chassis numbers. They clean extremely well without removing steel and disfiguring the number.

A rep from 3M gave me a heap of these hard black discs about 40 years ago. They are fantastic, they don’t remove any metal, but remove paint easily and don’t clog up. Don’t know if they are still available though.