Need Advice on Rain Channels on 78 Bus

[brainwash]

There was some surface rust in the rain channels of my bus and, since I had to take the fiberglass pop-top off to paint it, now seemed like the time to tackle it (typical project scope creep).

So using a crimped wire wheel and a stringer wheel (Milwaukee, HF didn't last and wires came loose while in use) and a got the bulk of the old paint and any rust off of the top (inside) and part of the sides (inside and outside)...

Now I'm flummoxed as to how best get at the rust in the outside bottom from underneath shown here...

Don't want further scope creep to make this into an all-out paint job, at least not yet. However, you can see the vertical seam in the air scoop needs attention as well (as do all the vertical seams on my bus, so any advice there is appreciated as well).

Need something really narrow.
Do I get a die grinder?
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'78 Westfalia

[Mike Fisher]

Siphon sand blaster from Harbor Freight & #30 sand from Home Depot.
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https://imgur.com/user/FisherSquareback/posts
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'68 Karmann Ghia sold

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[buguy]

Definately need a blaster when doing resto work. Its really the only way to get all the rust off.

[brainwash]

Great, thank you both!

Mike, a search for "siphon blaster" on HF gave me no results. I got, soda, abrasive, and gravity feed. Not sure which. Lots of variation in the abrasive: from 20# to 110#.

My compressor is only a 29 gal. 2 HP 150 PSI Cast Iron Vertical Air Compressor with Air delivery of 5.9 CFM @ 90 PSI, 7.3 CFM @ 40 PSI.

Will that work for sandblasting?
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'78 Westfalia

[buguy]

I would just get one of these. Great for smaller work. http://www.harborfreight.com/21-oz-hopper-gravity-feed-spot-blaster-gun-95793.html

You might be able to run something like this, but you would have to use it in short bursts. Takes lots of air to run a blaster. http://www.harborfreight.com/20-lb-pressurized-abrasive-blaster-68994-8799.html

[brainwash]

[Air-Cooled Head]

[buguy]

Those little gravity feed guns are the bomb. Super versitle. Just have to keep a bag of media nearby because they run out pretty quick. But you have a lot less mess (which is still alot!) and you can kind of blast in a smaller pattern. I watched a dude at work the other day blast an entire engine bay to some Ford with one. They also use much less air and have a trigger so they are more controlable.