1969 Chris Craft Roamer 46 Refit: Rub Rails

With the muffler platforms installed, I’m getting close to being able to make the exhaust risers. I’m working out how to make square cuts on 4″ stainless tubing, since it turns out the 4 x 6 metal cutting bandsaw I bought doesn’t track straight on long cuts. This is apparently a common problem, and exhaust fabricators sometimes use bandsaw blade guides to ensure square cuts. I’d prefer not to buy $300 worth of tools I’ll use just once and that aren’t in especially high demand. But while I stew over this and adjust my saw per some instructions online enthusiasts of these saws recommend, there are plenty of other things that need doing…like polishing the rub rails, since they represent the single biggest source of open holes on the exterior that need to be filled before the boat can exit the tent.

Sanded with 400, then 600, then 1200 grit sandpaper

Sanded with 500, then 800, then 1000 grit sandpaper

I’d previously sanded the rub rails and then installed them to protect the new Awlgrip paint from incidental contact with the Tent Model X upright frames during storms and days with very high winds. Even then I knew I’d have to remove them all to polish the rub rails and then reinstall. It’s tedious having to do the same job twice, but they served their purpose and protected the paint.

First pass with the rouge...big difference

First pass with the rouge…big difference

It takes about three minutes to polish each section between the screw holes.

Section by section, the rails get polished

Section by section, the rails get polished

There are ~40 screw holes per 20-foot stick of rub rail.

Shiny!

Shiny!

Fortunately, there’s immediate gratification in this job. It’s tedious, but the pay-off is worth it.

Almost to the end

All the way to the far end

After working my way down the rail with the coarser pad and rouge, I have to do it all over with the fine pad and polishing compound. But first, I’ll do the first polish pass on the rest of the rails.

Nice contrast

Nice before/after contrast

Hello...what have we here?

Hello…what have we here?

The black goop on the back-side of the rub rail in the picture above is the original 1969 bedding compound that Chris Craft used. It came off with the rail when we first started the project back in 2007~08, and exposed slightly corroded aluminum below. What I noticed here (and elsewhere) is that the bedding compound that stayed attached to the stainless was close to the screw hole.

Another spot where the OE bedding compound, paint, and primer pulled away from the aluminum hull

Another spot where the OE bedding compound, paint, and primer pulled away from the aluminum hull

I took the pic above after I’d already used a razor blade to remove the original bedding compound, paint, and primer. When bedding compound, paint, and primer all pull away from the aluminum below, it means water got under the primer.

The source of the paint and primer failure?

The source of the paint and primer failure?

Each screw hole has a very slight ridge around it that wasn’t reamed or sanded smooth back in 1969. The ridge isn’t enormous, but it’s on the back-side facing the paint and is at least as thick as the paint. With vibration over time, I’m speculating that the ridge filed its way through the paint and primer, letting water react with the aluminum molecule by molecule. This, plus the fact that the original screws were not installed using TefGel, might explain why the paint sometimes fails on these boats in the vicinity of the rub rails.

Before polishing, each hole gets deburred and sanded flat

Before polishing, each hole gets deburred and sanded flat

Another one down, another to go

Another one down, another to go

I ran out of rouge and have ordered more, but I made good progress on getting the rub rails polished. This is a good “time filler” when I run out of supplies or need parts on some other job. I’ve got the process worked out, and with the deburring and sanding to remove the ridge on the backside, hopefully once the job is done I’ll never have to polish these again.

Next up in our 1969 Chris Craft Roamer 46 Refit: Running Lights

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5 comments on “1969 Chris Craft Roamer 46 Refit: Rub Rails

  1. Frank says:

    Not to be interpreted as a criticism, but as a life long mechanical contractor: the cheaper the tool, the slower you go. I work with technicians that can cut a perfectly square pipe/tube with a dull hacksaw. Let the speed of the tool do the work for you. If it is not working, slow down. Only cut on one side if that is what it takes. Do not push the tool. If you are in a hurry, spend the money for tools that allow you to just slam it thru. Rotate the work to only cut on one side of a box/circular dimension.
    HTH

    • 1969roamer46 says:

      Hi Frank. No offense taken, but this is a metal cutting, low-speed, auto-feed bandsaw. There’s no pushing of the tool–it cuts only as fast as the blade and gravity allow. And like I mentioned, they’re notorious for not cutting straight. And you’re right, cheap tools suck. lol
      I’ve been toying with the idea of doing repeated cuts on a line around the tubing, but that seemed…crude. Also, the cuts are in the middle of mandrel bends, so it’s not as simple to scribe a square line as it would be on straight tube. I don’t want to end up with a cut that looks straight but puts the pipe at the wrong angle.
      Stay tuned!

  2. Dan Stokely says:

    easy way to cut exhaust tubing is put a hose clamp on the tube, scribe a line, cut tube above line, grind to line with hand held 4 inch grinder. Result will be a perfect cut every time!

    • 1969roamer46 says:

      I’ve been thinking about the hose clamp method, Dan, but the cuts I need to make are on mandrel bends. I tried the hose clamp method three times at the same point, and I ended up with three different lines. They’re only off by a few millimeters, but that’s a lot of degrees off once this is welded together. It’s not as simple to scribe a consistent square line on the bends as it would be on straight tube.

  3. Kent says:

    I did the Rub Rails on my Connie back in the day– Of course my hull was wood though..
    Really looking forward to some day visiting your Roamer!!

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