Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Paint primers for winter protection

I have just emerged from the Archives. I was looking for a thread I remember about the use of paint primers that would be best suited for protecting a body tub over the winter months; you know - cold, damp air, condensation, all that BAD stuff. No success at finding the particular discussion, although there is lots and lots of good stuff about paint methods and materials.

The specific issue is this: Sprite body tub is nearly ready for an intimate stripping session with a "sand" blaster which will get it back to bare naked steel. I need then to protect that surface during the cold months of the year as it won't be getting top coated before next spring at the earliest.

I plan to give it an immediate coat of etch primer hopefully within minutes of exposing the bright steel and before atmospheric moisture begins the inevitable micro-rusting of the surfaces. But neither acid etch primer, nor ordinary primer, prevents damp getting through to the underlying surface, so it needs another treatment.

One possibility is to spray a couple of coats of cellulose without bothering about any of the preparation steps. This would, I think, seal out the damp and it wouldn't matter what it looked like as much of it would be sanded off again in the spring. But there's probably a better solution.

The thread I was looking for in the Archives was, I think, about just this problem. And I think mention was made of a waterproof priming system that sounded just what I need! I think it was Neil from Pembrokeshire (where they get lots of salty rain!) but the Archive search doesn't allow one to narrow down selection by author, or by much else, it seems!
Guy W

Guy, was that discussion this year? I seem to remember it being in the general section?
Lawrence Slater

Stripping a shell at this time of year and then leaving it over winter is probably not a great idea. But I think you have 2 options - either use a non hygroscopic epoxy primer to seal the surface - or use a rust proofing spray that containes no waxes or silicones - in this respect Gibbs Brand behaves like WD40 but is overpaintable. It would be better to strip and apply whatever coating in a heated and humidity controlled environment - if not you run the risk of mico blistering later on.
F Pollock

I think epoxy primer will seal out moisture.
Trevor Jessie

Bonda Primer - Epoxy primer with added Zinc, I found a review of a bloke with a mild steel narrow boat who had painted his boat and 5 years later was still good, and lots of discussion on landy and off forums rating it highly.

Lots of marine stores seem to carry it ( a good thing I think) but charge a fortune.

I have been using it for about 2 years, it's red in colour, stinks like old paint, is as thin as water and dries in minutes.

I got it from here

granlyn paints,
Bank Street
West Bromwich
West Midlands
B71 1HF

The people make it are in Kent - so ring and ask Bondaglass Voss Ltd
Tel +44 (0)20 8778 0071
158-160 Ravenscroft Road, Beckenham, Kent, BR3 4TW
Malc Gilliver

I've got the same stuff Malc. I painted the floors, front and back, of my Sprite in the stuff back in 1999/2000 ish. The floors, esp the footwells have been wet quite a bit since, and no trace of rust at all. I also covered the insides of my new boot and bonnet in it. Again no rust at all in the usual places.

I recently bought some more for the midget, and it's still the same stuff as it was 13 years ago. I reckon it's great.

I bought it on Ebay. 30 quid plus 5 quid postage for 2.5 litres. Cheap it's not, but it gives GREAT coverage. You can easily paint a complete Spridget shell with 2.5L, using a brush.

Cheapest on ebay is still the same seller.
Lawrence Slater

This Bonda Prima sounds like good stuff, although I don't think it was what was mentioned in the other discussion that I was looking for. There are good primer systems out there, but even then the primers are not necessarily waterproof until coated over with the car top coats. So the fact that panels painted with Bonda Primer have remained rust free may not be quite what I had in mind if they were additionally coated with a paint finish.
Lawrence, were your Bonda Primer painted panels overcoated with anything else, or just left in primer?
Guy W

Guy, on my sprite floors -- insides -- just left as is. Probably 2 coats of the bonda. The boot lid and bonnet were oversprayed with grey primer and OE white. The under floors and wheel arches were given a few coats of Carplan underseal directly over the bonda primer.

Oh and it thins with celly.

And just remembered the insides of the wings were stripped back and bonda applied, followed by underseal directly over that.
Lawrence Slater

OK, thanks Lawrence, so it works on its own as well. That's good.
Being an Epoxy based paint, does it need to be mixed with a hardener?
Guy W

Nope I just use it straight out of the can.

I sprayed with it too using a little electric spray gun. I even used it with the pump/spray from a waxoyl kit to get inside the sills on my sprite and other nooks and crannys. I'm going to do the same on the Midget. I can't remember if I thinned it to spray though, so I have to experiment agaain. Chances are I did thin it though.

I've used it over surface rust too. But I don't know if it converts the rust or just seals it, and stops it getting worse.
Lawrence Slater

No Guy,

Just paint it on and will dry in a max of 15 mins, it will take you at least 30 mins to stir all the stuff from the bottom in, I have reached the sad situation that I keep it on a shelf and every time I go into the garage I turn the tin over !

I think Granlyn charged me about 27 for 2.5 litres.

I remember ringing BondaVoss and I'm sure they would sell direct, but they will also tell you if you have a stockist nearby, it'll be a auto / marine paintshop supply company, so might be a good contact for when you come to paint, next year.



Cross posted with Lawrence - I'll bet you didn't thin it, it is very thin, but I haven't sprayed it and I use it over a rust killer kurust type thing
Malc Gilliver

For no more time then it takes to strip a midget to bare metal... id avoid the risk and wait till next spring, I know its not the answer your wanting ...just my 2 cents

What about coating the car in a layer of grease ...then just wash it off next spring with acetone or some kind of grease remover

Prop and the Blackhole Midget

Prop (and others) its not that I just plan to put it away into store for the winter. There is more method in my madness than that.

Its a MK 1 Sprite. I have the whole rear deck and rear wings off the car as a unit. All of the rest of the welding and repairs to the body tub are just about finished. I want to get the inside surfaces of the rear clip, and the inside of the whole boot area blasted back to bear metal whilst they are off and access is good. There is quite a lot of surface rust in there and all the shapes would make it very difficult to get at later when assembled.

So the plan is to get it cleaned off now, primed or whatever to protect it. And then to carry on working on the shell, reassembling the rear end, seam sealing etc through the winter. Then get it fresh painted in the spring. So covering it in grease for the winter isn't really going to help!
Guy W

I like the sound of the bonda and may well try it in future but a couple of other options are available from rustbuster (and no doubt a few more from others).

For painting on to (light red) rust they use Epoxy Mastic which converts and covers ready for top coat. If you are blasting to clean then custom epoxy 421 is the primer of choice (and what I've used).

Both are two part eg have a hardener, are not porous and can be left indefinitely before top coating. You will need a warm painting area for them to flow and set properly.

Best of....
M McAndrew

I painted a complete Midget with Bonda Primer, back in the early '80s.

It was a rolling restoration - my daily driver - so I was paint stripping a panel at a time. It was 13 years old at the time and had been three different colours.

I decided to take it back to bare metal and start again. It gradually changed from a putrid yellow to Bonda Primer red, panel by panel, before I finally sprayed it with grey primer and Flame Red celly.

AFAIK it's still on the road.
Dave O'Neill2

I've found a blurry photo of the Bonda Primer Midget!

Apparently, UBE959H is still taxed...although by now, it might have a 1500 engine and bodyshell ;o)

Dave O'Neill2

Lovely plumage, the UBE959H...

Actually, it is I like the old Bondaprimer red meself.

<<it's red in colour, stinks like old paint, is as thin as water and dries in minutes>>

I've recently bought some from the same place as Marc. 29 for 2.5 litres.

It is thin, far thinner than I remember.

Dave O'Neill2

Sorry, *Malc*
Dave O'Neill2

I don't think it's "that" thin is it?. Well at least the stuff I bought mid last year wasn't. It's not what I'd call non-drip, but I've found it goes on thick enough in one coat.

As in this pic.

My only complaint is the cost of the stuff. Although it does cover very well, it goes a long way.

Lawrence Slater

Guy, you want to galvanise it?

Hi Matt,
Wasn't planning to.
My original question was raised last October when I was thinking of stripping back to bare steel and wanted a waterproof treatment to see it through the winter. But as is often the case, it was easier to do nothing!

So when the weather warms up a bit more I will just get it stripped and prepped as normal. But I am inclined to use an epoxy polyurethane primer, if I can find such a product. I think that was the stuff that I was looking for last year that Pembrokeshire Neil had used.
Guy W

I've primered some more floor tonight and it seemed a lot thicker than it did at the weekend.

I'm guessing that some of the solvent had evaporated off, but if it carries on like that, I will have to start thinning it!
Dave O'Neill2

I hate to say this, but you have spent 30 mins stirring it ?

I find about an inch of goop at the bottom of the can.

Malc Gilliver

Yes, I did stir it well, but it didn't seem to make much difference.
Dave O'Neill2

This thread was discussed between 16/10/2013 and 27/03/2014

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.