Black Spots during polishing?

[chazwars]

I have just begun the polishing on my '56 22ft. Caravanner. Yikes, here I thought this would be an easy project. I started up with a compounding polisher at approx. 1200 RPM with 7" wool pads. I am using the Nuvite G7 as a starter. When I follow the suggested techniques from vintage trailer supply, I find a significant amount of black spots.

I searched the forums and found that sanding might be an option. I hope this is not the case. So, my question is this:

When polishing, is it normal to get these black spots? And, if so how do I get them removed? Or do I just need to keep going at it?

Thanks,
Charlie (Newbie)

[Fyrzowt]

Try slowing the polisher even more. You may be getting hot spots?

And welcome to the forum!

[chazwars]

But I don't want to go slower. I want the project done right away.

Just kidding, I'll slow 'er down and see how it turns out.

Oh and thank you for the warm welcome. I am so grateful you all are here. I am glad to be a part of.

[InsideOut]

Are the "black spots"

A) specks - like corrosion pits or
B) large irregular gray/shadow splotches?

If they are the specks, slow it down and keep at it. If they are the shadow splotches, that seemto "grow" STOP. You may have burned the aluminum or gone through the Alclad...more polishing will make it worse.

Polishing is not to be rushed...you kinda gotta get in the zone ~

Oh yeah, pictures...we want pictures! Especially from a fellow '56-er!

Shari

[chazwars]

Yep, they are specks. I slowed it down and took my time. That did the trick. Thanks. Now, I've come to see white specks and bumps. I was under the impression that these would be worked out with the G7. If they can't come out, I can live with it. The old toaster is shinin' up nicely.

I don't know how to add pics to the message, so I'll try to attach some. The first two are when I purchased it from Dan at vintagecampers in Indiana. The third is a picture of the specks. I'll send some over tomorrow when I get a few panels knocked out.

Long live polishing. It will be my LIFE for the next 10 days. Don't worry, I have a "real job".

-Charlie

[digger bear]

Looks like you have a great unit!

Polishing is a marriage, you will not be able to do a ten day run and forget it. You will also find you will develop a “discontent” knowing you can do just a bit better. For me (and some other group members) it has become an obsession.

Its possible the black bumps are excess polish. It is surprising how little you really need.

You are not too far from me, if you are ever heading south, be sure you stop by and see our baby in process -- Ill fire up the smoker.

[gypsygirl1]

Nice lookin' unit. Happy polishing to you, and please keep sending the progress pics.
Our '59 is in about the same condition, and we're hoping to polish her, too.

[chazwars]

I had a thought last night that I might have to do a strip of old clearcoat, or what ever was used in '56. I searched the forums and saw mention that there was no clearcoat in '56 trailers. I also tried the "toothpaste" test. It didn't turn jet black. I am not sure why it looks like clear tape with air pockets under it. I'd shoot pictures but it doesn't come out very clearly with my camera.

Thoughts??

[digger bear]

I don’t know about the clear coat situation on a 56, hopefully one of other members will chime in here – I have a 73 - it had been clear coated and looked like Hades. One of your rigs PO's may have had it coated as well.

You (or at least I) can’t polish off clear coating. We pulled our unit under a large tree in the backyard and used Hydrostrip – it has some sort of peroxide base (I think) that didn’t kill our grass or burn our hands. After about 45 minutes I simply washed it with water from our garden hose and the nasty coating simply fell off in sheets. We did a second run on a few tough spots and got off about 95% of it that way. The AS looked 300% better after that alone!


I began compounding and bought a cyclo.


It was around that time I learned to crave the aroma that only comes from the unique blend of Nuvite and homebrew…

[InsideOut]

It doesn't appear that you have clearcoat...it would not have been original in '56 and highly unlikely a PO coated it. Besides, from the pics (thanks!) it is an overall even "gray" which is just oxidation...not milky white, uneven failing clearcoat.

If you have some Nuvite "C" you might try that. It seems that the "G", while coarser, breaks down faster so it may not cut through the oxidation as the finer "C" which stays effective longer may. We have had great success with "C".

Also, using too much polish "lubricates" more than "cuts"...teeny, tiny dabs is all you need. Keep at it, you'll get the feel for "what works" on your trailer...every one is slightly different.

Some folks are using Tripoli and a giant buffing wheel on a drill for the first pass...then switching over to the Nuvite products. That's what we are doing on our '56 which has more corrosion than our '64 did....but we have just done areas like window frames (which are not Alclad) and areas around lights & trim during our restoration, not entire panels yet. Also to knock the bumps of corrosion off, you may want to try a fine (we have used gray & green) Scotch Bright pads by hand...which will smooth them out but scratch, then work on getting the fine scratches out with the compounder. Again, be careful so as not to go through the Alclad layer...if you do that, there's no going back.

There are as many different techniques to polishing as there are polished trailers...some things "work" for some people & trailer conditions and others work for others. And somethings work on one panel of your trailer and other panels may need something different...the key is finding what works for you.

As for polishing being a lifetime commitment...it is, but only the first time is as much work as you are experiencing now. THIS time you are trying to get 52 years worth of oxidation off...next time it'll be only a couple of years worth. Our '64 has been somewhat neglected this year...it's been 4 years since we did our original polish, but it still looks good...next spring/summer, when we are finished with our '56 we'll freshen up the '64.

Shari

[chazwars]

Thank you for all the info. I will try out the "C" to see if it will cut a little more than the G7. In the meantime, I did pick up some hydrostrip (ICI sells it as Bare-Z-All now) and testing it on the door panel.

Here's to polishing!!! I am just glad I farmed out the floor and cabinet work or I'd make this a career.