• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Rust Removal - best methods?

Share this page

RickB

RickB

Yoda
Offline
I know I posted similar thread over in "MG" but I figured some of you never leave the Spridget area...

So:

Now that I'm getting down to actually cleaning up the rusty areas on my MG(C) I am wondering about methods of rust eradication.

I could go at it with a wire brush attachment on my angle grinder. That's been my "plan A".

I was wondering about some kind of sand blaster?
Anyone have any experience with anything like that?
I own a compressor.

Just thinking of what might be an easier way of cleaning it up without causing more damage than what's already there.

I'd be doing it from underneath, not a lot of clearance.
I'm toying with an idea to lift the car up another foot or so, it's sitting on 4 jack stands at the moment.

I'll post another picture here in a moment, (definitely not surface rust). This is deep rust we are talking about.

A sand blaster of some kind seems in my mind to be the best idea, less actual contact between the operator and the patient should equal less operator fatigue and therefore a better and faster outcome. If it will manage to penetrate deeply enough.

Here's a good example. Linking it because it's a big one (2080 x 1544 pixels):

example of my rusty areas

That's the floor area on the drivers side (left). The passengers side is very much like this. These are pretty much the worst areas on the car (that I have found).

Thanks.
 
How insensitive!!....we know you're just making fun at Speedy_Pete on next post. "Bought new SPrite today"....
 
Definitely going to need a sandblaster. Have you considered stripping the tub and having it professionally done?
I spot blasted my midget without completely stripping it. (It was a rolling refurbishment). I'm doing another car now, and I'm going to strip it to the bare tub and blast it all at once.
 
I saw that one, I figure Spridget owners know a lot about this subject.
I'm already in the rust prevention war with my Midget. It's got a remarkably rust free body but I can see where it happens. I've hit a few rusting spots with anti-rust paint already.

Seems like engineering to prevent water from getting into areas wasn't the top thing on the creators minds.

For example: Like when you open the bonnet on a wet day, where does all the water go? You can see rivers of it flowing along the channels on the sides. OK that's better than just having it pool but you know it finds it's way into cracks & sits in places.
 
Trevor, my intention is to pull off the bad fenders & trash them and get anything else off of it that will be in the way.
I don't have the budget to get much of anything "professionally done" so this will be work I will have to do myself.

Ok, I'm off looking for a sandblaster tool on Ebay.
Thanks.
 
The real issue is having/borrowing a compressor that can keep up with the sandblaster.
 
So a small one won't do the job eh?

My BIL has a big one I could borrow. He lives less than a mile from me.
 
It will do small jobs, but it looks like you are going to be blasting quite a bit. It is very frustrating to blast a small portion, then sit there with a hot hood and respirator mask waiting for the compressor to catch up.
 
I was thinking of getting something like this:

Sand Blaster

What do you think? I could get a twenty gallon or a five gallon as well. I guess the thing is having a big enough compressor to make it run.
 
I use something very similar. It is important to have good dry media so that you do not have clogging issues.
 
I think at least 15 CFM @90 PSI for a decent work rate. You could go as low as 12CFM and not get too frustrated.
 
You have "thorugh rust" on the floor panel. Take a pointed hammer (not a ball or carpenters hammer) and bang the rust. Hit medium hard. If it goes through (which it will on the floor, and not on the chassis member, and maybe on the strengthener), then you have to put in new metal plate.

Sand blast the parts where there is surface rust and the hammer didn't go through. Cut the through rust out with metal cutters. Buy some metal plate, 1 mm or 20 gage. Form the metal with a hammer and dolly. Weld it in around the edges. The nicer you form the piece, the nicer the repair will be. Overlap the original panel with the new metal about a cm or less. Do nice welds and maybe you will not have to grind them down smooth.

Zink primer, top paint and rust protection afterwards.

Five hp compressor should be enough I think.

Donn
 
Hi Rick:
I'm kind of fence jumping today. I'm involved in a frame off restoration on a TR3A. I have both a bead blaster and a pressure sand blaster. They definatly save time, I can tell you from experience that a wire wheel on a drill won't cut it, so to speak. However you need to understand that you need a big compressor(60 gallon) air reserve, putting out 15 to 16 CFM AND you need to do it outside. With all of that said from what I see of your rust pictures I really feel that unless you start taking things apart you will be getting rid of less rust than you might find that you actually have.
Some safty points: Wear protective gear, sand can give you slicosis which is nasty stuff. If you are going to lift the car and crawl under it use solid wood to support the car and don't trust jack stands or cement blocks.
Equipment should be largest your budjet can stand. I have a blaster that holds 90 lbs of sand, it gets used up very quickly.
Anyhow hope that helps, if you have any questions feel free to PM me and I will answer them the best I can.

Good Luck, Tinkerman
 
I had good luck with removing the hood and putting a sling around the engine and lifting the entire front of the car way off the ground at over a 45degree angle. I used purple cleaner(undiluted) to remove all grease then a wire wheel to remove rust and then naval jelly on those spots to get any that the wheel missed and then a coat of por-15 after that , then topcoated with brush rustoleum. I don't think I will have any trouble with rust in those areas again.
MVC-153F.jpg
MVC-150F.jpg
MVC-145F.jpg
 
I've done 3 cars myself. I have a pot similar to the one you are looking at. The first car was an XK120 body only on tall stands. I did that one in my shop with an improvised plastic tent using silica sand. Went pretty well and clean up was a pain but doable.

The second (several years later) was a MGB and I only did the engine bay (engine out) and rockers. When I went to the local abrasive supplier, he refused to sell me silica sand. The problem is silica on metal produces a super fine dust that hangs in the air for long periods of time. He would sell it for use on wood. I could have fibbed and gone home with a couple of bags but took his advise and took some stuff called Black Magic which is a slag byproduct. It worked fine. This time I was outside so cleanup wasn't an issue.

Third time was the Bugeye I just "finished". Back indoors this time with the Black Magic and a plastic tent. The car came out OK but what a mess. I don't think I will ever have a clean shop again.

In the meantime, I have discovered a local sandblaster that is very reasonable. He charges $60 an hour and did the Bugeye bonnet as well as a hit-miss engine block in 1 hour. He also did the body panels for a Healey 100 in 1 1/2 hours.

Bottom line - I've sandblasted my last car. For a little more money and a lot less mess, I can get someone else to do it. (and I'm a guy that does almost everything myself)

Marv James
 
IMHO... it's a sliding scale.

There's only one way to 100% remove rust, and that's to replace panels wholesale. Period, end of sentence. Cut or drill out the entire part that visibly shows *any* trace of rust, plus several inches beyond, and weld in new metal. That's the only way to ensure you have no rust. Incredibly time-consuming, difficult in structural areas, expensive if you're not doing it yourself.

An option that's less time-consuming (maybe) and *almost* as effective would be acid-dipping, followed by thorough rinsing and some sort of rust-preventative dip. (see for ex. Surface Processing Ltd. ) Very spendy tho, and difficult in cars with lots of enclosed box sections, for obvious reasons.

Tertiary options are; grinding, wire-wheeling, electrolytic rust removal, chemical treatments, Paint-Over-Rust (POR) treatments, etc. All can be effective, if done correctly, but none are permanent or perfect.

It's all a matter of balancing out;

- how much you want to spend,
- how long you will have the car,
- whether you are willing to keep "fixing" the same areas every few years
- the tools & time at your disposal

I've used pretty much all of the above, although I've never dipped an entire car. My Rabbit is in the middle of replacement of 80% of the unibody with brand new panels. The Midget has just had its floors stripped, acid-treated, and zinc-primed, soon to be covered in Rust Encapsulator and topcoat. I expect not to have to revisit the issue for as long as I own the car (perhaps five years).

(Sorry for the ramble... See what happens when I take a sick day?)

-Duncan
 
At the moment I lean towards "cut it out & weld in new metal".
I have been casting a quizzical look in the direction of the POR-15 floor panel replacement system though...
 
The por-15 works if you do what they say and works great, its the only stuff I have ever found that seals and stops rust permanently. If you put it over rust and let it dry you have to grind it to get it off.
 
Here's my opinion on sandbalsting yourself, hire that crap out! I own a nice TP sandblaster, It permantly loaned to a friend who uses it to restore old antique bath tubs. First off you need a freaking huge compressor or you'll be stopping every 5 minutes or so to let the compressor catch up, you can go rent a big job compressor for a day though. Then there's the mess, to do a tub all over you probably need 25-30 100 pound bags of sand and you are not going to believe the mess this job will make, imagine 2500 pound of sand lying on the ground around your house or garage, much less having sand in every imaginable orfice of your body for days after the job. Take it from someone who has done this, hire this job out, forget about that walnut shell crap, a good blaster can do a great job with sand. This coming frm a person who has done atleast three complete tubs myself and hired out another 6 or 7 tubs. There's a guy around here that will do complete cars for $200, he going to get my money should I need this again.
 
Around here in the Seattle area the quotes that I have gotten you just need to add one zero to Hap's quote (yes- around $2000.00, PLUS priming costs). It is just wonderful to live in a place where the EPA runs everything!!
Bill
 
Back
Top