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Triumph TR6 - Underbody cleaning

My 70 TR6 was recently painted without removing the body from the frame. It had southern storage and was remarkably rust free except for some minor surface rust on the frame that flakes right off. My question is what is the best way to strip the frame/floorpans of the very minor surface rust. I would like to paint or coat it for more rust protection since it now resides in Indy (it will never see snow!) By the way I have registered for membership several times, it must be my computer because it keeps showing up as a guest. I can access the archives so I presumed I was registered.
Bill Kinney

You might need to set your 'favorites' address to

If you try to go directly to the TR6 page, it seems to skip past the registration (at least, that's how I solved my registering problem). But this method makes you click on each step to get to the TR6 page.

Since you recently repainted the body, sandblasting (or other media) may be out of the question, because it could scratch your new paint, likewise chemical strippers. I would probably try using a wire brush on a drill and see how that takes the paint off, before going to other, more agressive techniques.

R.C. Blair

Hey, Bill. I used a great big can of Waxol (Waxoil?) to cover the underside. That was 12 years ago, and I haven't seen the product lately. It supposedly had rust inhibitors in it to stop what you describe in it's tracks. It appeared to me to be a hard parafin wax dissolved in mineral spirits - so it left a coating. Oil leaks will of course compromise the wax, but leave an oil coating. I'm kind of curious what others think about the Waxol stuff - does it work well and is it still available?
Brent B

3M makes a rust and paint removing wheel that fits on the end of a hand drill. works great! probably 3or4
to do the whole frame.You should degrease the metal frist with solvent.
Christopher Trace

I had heard about Waxoyl when I was doing my restoration here in Canada and so on my next trip to UK, it was off to Halfords to buy a kit. At Heathrow they wouldn't let me take it on board - and that was in 1988. I had it shipped and did all the closed box channels you are writing about. I didn't make any holes. With the long rigid tubular rod (or wand ?), I put it into the 1/4-28-UNF captive boxes with nuts and traversed from one end to another of the inner and outer sills plus the box section under the rear valance. I also sprayed inside all the cross piece tubular sections of the frame as well as inside the box sections from both ends. The rear end is open and up front, there is a tiny hole at the front end.

I also liberally poured rust proofing paint into the inner sills before welding. It was dripping out the face-to-face spot welded flanges, so I knew that would be protected. Also in the rear cross section, I brushed this paint. I also did the outside of the inner sills as well as the inside of the outer sills plus the inside of both rear quarter panels - all before welding into place. I also sprayed Waxoyl into the inner sections behind the quarter panels before installing the interior trim panels. In over 78,000 miles during 14 summers, I have no signs of any surface rust so I assume it's all OK inside too.

I'm close to the same stage of restoration as you are - and I'm just about ready to do this on TS 81551 L.

But this time I made up my own Waxoyl. Here is the recipe.

Don Elliott, 1958 TR3A, Montreal, Canada
Don Elliott

Thanks for all the advice. Would using a product like naval jelly and then using the abrasive wheel work well? Also if I used the naval jelly, will the metal be able to be painted/undercoated without further prep?
BOK Kinney

I haven't used naval jelly in 30 years, but "if" I remember properly, naval jelly makes a coating that bonds with the rust and base metal. If your paint is flaking, you'd have to clean off the flaking paint to use it. I also seem to remember that naval jelly can be painted over with light sanding to provide tooth for the paint to grab on to.

After wire brushing, you might want to consider using "Rust Encapsulator" (go to" and then paint over that.

Either way, you'd want to wire brush to get as clean a surface as possible BEFORE coating the metal.
R.C. Blair


I wouldn't use naval jelly, which is basically a viscous phosphoric acid, unless you make sure you neutralize the surface afterward. Otherwise you leave the surface in an acid state, which actually promotes rust. I would remove the rust via one of the mechanical methods described above (I prefer an angle grinder and wire wheel) and then apply a product which actually converts any residual rust to a paintable substrate. Duro makes a product called "Extend" and Rustoleum also makes a similar product, the name of which I don't recall. These may be similar to what R.C. desribed above.

One sort of off-the-wall suggestion that I have done on my 6; I filled the frame with Great Stuff, the weatherproofing foam you can buy at Home Depot or any hardware store. By strategically blocking off certain sections at a time, you can basically fill the frame with expanding foam which creates an oxygen barrier on all inside surfaces of the frame that you really can't get to otherwise. It also has a noticeable overall sound deadening effect. Granted, it's a bit of a mess (make sure you wear gloves if you try it)and will be leaking all over the floor until it stops expanding, but once it all dries you just cut it off and throw it away. It's the best method I know for stopping corrosion from the inside out.

Jim Vandenberg

Great Stuff, what a neat idea. Very creative. Do you have any data on its long-term stability? Just curious if it shrinks at all, which could allow air and moisture to get trapped between the frame and the foam.

Rick O.
Rick Orthen

Our family car is a 1992 Buick which I bought brand new in 1992. At that time it was normal for GM to inject foam into the windscreen posts and also down the "A" posts where the hinge points for the front doors are located. Over the years, water had gotten into this area for at least the driver's side door post and it rotted from the inside out. I took it to a body shop and he told me that the first thing to do would be to get that foam out. Once it gets wet, it never drys. Buick and other GM cars don't use this technique any more.

So my suggestion would be to avoid the foam.

Don Elliott, 1958 TR3A.
Don Elliott

Rick, I did it about a year and a half ago so I don't have any long term stability theories yet. I do know that it's very dense and pretty tenacious when you try to tear it up by hand. I just decided to do it one day when I was cleaning up the frame exterior and all kinds of rusty dust and flakes came flying out of the vent holes when I stuck an air gun inside. Since I was working so hard at preserving the outside, I felt compelled to do something to prevent deterioration from the INSIDE. Don, I can understand your concern but I'm not really worried since my 6 never sees anything but dry pavement and is stored in a heated garage. I also found some solid rubber grommets at the hardware store that fit the vent holes very nicely. I guess time will tell...

Jim Vandenberg

Hi Bill from a Canada point of view external coat would be Por-15. Give it a scuff down with a wire brush. Clean with either there prep products or a good one to get grease off. Rubber gloves and a painters suit and face cover. Like epoxy you need a grinder to get it off. This sight is Canada US is cheaper. Likely about $75.00 bucks for everything you need. Check the 4 can chassis one?


Bill Brayford

Bill Brayford

Hi JimV

Now thats an interesting idea. My interest is more for increased frame rigidity without weight than rust proofing? Working on frame.

Since reading your post I have been trying to get more info. Some of the rodders say it developes large air pockets in enclosed spaces because of propellant? But manufacturer claims super dense no water absorption cured?

Think I'll steal a piece of the wifes 2" clear pond tubing block off the ends buy a can and fill. See if I come up with a bat or a noodle.

Something many are not aware of is there are metal baffles built into the frames interior. Designed to offset torquing. Same idea as the 2 by 2 Xs in between your house floor joists. Center section has the most. So to get a full fill some areas would have to be hit every 12" to 18"? Even on dry cars those baffles rot out fast so may not be a big concern but might leave some pockets.

At this point all conjecture but will let you know.

Bill Brayford


I learned about the baffles myself when I was trying to remove the acorns some chipmunk had stored in the frame over the winter, but that's a different story. So I actually drilled a few small holes (dispensing tube from can is only about 1/4" in diameter)in the frame in strategic locations to try to maximize penetration. Regarding expansion, you'll see that it expands so prolifically that it is unlikely there will be any air pockets. I like your idea about the clear tube test. I guarantee you it will be a bat. Remember, wear gloves. This stuff does NOT come off.

Jim Vandenberg

Hello all Just some more information on this. This is not the first I have heard of this I did idea. Must be about 15 years ago when I rebuilt a mg for someone else. A prior owner had filled any and all cavitys of the car with this stuff. like between inner and outer fender. It was a pain in the but to remove and it is VERY flamible. be careful where you put this stuff. dave
dgf Finch

This thread was discussed between 09/03/2004 and 12/03/2004

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