Archive for the ‘Paint’ Category

Mötsenböcker’s Lift Off Latex Paint Remover

Sunday, April 15th, 2012

Neighbor Dan got the front brake hoses put back on and the brakes working. In spite of another brake problem, I drove the bus to my house to work on over spring break, with the two main intentions being removing purple paint and readying the interior for carpet.

The first part of the week was non-stop rain, so the paint removal waited until Thursday. It turned out to be fairly effective but still time-consuming, so I didn’t get as much done as I would have liked.

Schoolbus covered in purple latex house paint

The bus, as you may recall, is covered in purple latex house paint. I’d like to repaint it some other color, but the latex isn’t tough enough (nor was it applied well enough) to paint over. A wire wheel on an angle grinder takes all the paint down to bare metal quickly; but I’ve been looking for an intermediate approach that would get the purple off without forcing me to immediately mask, prime, and paint the whole bus — a significant undertaking for which I’m not ready yet.

I recently searched again for a chemical product that might be effective at removing latex while preserving the underlying factory paint job and found Mötsenböcker’s Lift Off latex paint remover. It’s clearly targeted at removing latex spills that haven’t cured yet, but I figured it was worth a shot. It says it can remove latex paint from doors, tables, etc. — things from which you wouldn’t want to strip the original finish — and buried in one of its brochures is the claim that it can remove latex paint spills from cars. Still bearing in mind that it’s probably talking about fresh paint, it seemed worth a look.

I see now that it’s available through Ace Hardware, and I’ll try Graber’s for my next jug. But at the time, the only place I found it was through the Home Depot web catalog. It says it’s available for in-store pick-up, but that doesn’t mean it’s available in-store; it means you can pay the full shipping rate to have it sent to the store so you have to drive there yet to pick it up. (I don’t understand people who design web ordering systems and why they don’t spend more time shopping at Amazon.) So I paid $20 for a gallon and about $8 to have it shipped.

Schoolbus with some purple paint removed

It smells like bitter apples, it says it’s biodegradable, and it works on years-old latex paint in varying degrees. Some of the paint became as soft as a balloon and I was able to scrape it away in yard-long ribbons, making a perfect division between purple and yellow. Some of the paint didn’t seem to soften much at all. It absolutely and single-handedly made it feasible to strip the purple paint.

Several observations and tips:

  • Scrub the surface clean before you start. Lift Off over dirt just cleans the dirt and doesn’t soften the latex.
  • Put it in a spray bottle. Spray it generously onto the surface, keeping in mind that any runoff is wasted. As soon as it’s dry enough that it’s not running, spray more. My best results were in spots and during times that I was able to keep the surface damp for an hour or more through repeated application.
  • Remove anything that’s not latex before you start. I thought the black lettering was done in latex, but it didn’t soften at all and it prevented the Lift Off from working on the purple paint underneath. I later removed the black paint with a scrubby-abrasive disk on my drill and the Lift Off mostly worked on the purple under it.
  • Don’t expect to scrub the paint off with a sponge or brush. The softest parts came off nicely using a razor scraper. The medium parts came off poorly using a razor scraper. The tough parts came off poorly using the abrasive disk and the drill — but less poorly than without Lift Off.
  • Its effectiveness varied dramatically across different areas, and I haven’t figured out why. It doesn’t seem to correlate directly to sun damage to the latex — the paint on the window stiles is tougher than the paint on the body panels.
  • It does appear to have slightly softened the yellow paint, though not so much as to concern me for my purposes.
  • It was well worth my expense and I expect to use at least two more gallons, on the other side and on the roof.
  • Be responsible and pick up your latex paint. Latex is not a biohazard and Lift Off is biodegradable, so household trash disposal should be fine.

Sanding Away “The Landing Strip”

Schoolbus with former owner's logo

I want the bus to be innocuous and not draw attention from vandals; nor turn KSU rivals into vandals; nor draw undue attention from law enforcement, who have a tough job to do, have stressful encounters all day, and can create stress and take up a lot of time even when one is meticulously abiding by the law. So in addition to wanting to be rid of the purple paint, I’ve been eager to get all of the lettering off as soon as possible.

Schoolbus front-end header, sanded

While waiting for one application of Lift Off to do its magic, I climbed up onto the housing aft of the hood and sanded the name off of the header above the windshield. It was more black paint, so it had to come off for the Lift Off to work (next time); and it’s good to have it gone already.

A Song for the Bus

Sunday, July 12th, 2009

Stripping paint on a schoolbus

Acetone, my friend
You scrub the paint so easy
You poor old solv, you see it’s only practical to use you on small areas darn it

Serious Paint Removal Attempts #2-3

Saturday, June 20th, 2009

Purple paint stripped from schoolbus with fine wire wheel on angle grinder

Tuesday night: Fine wire wheel on angle grinder. Pretty slow going, and it tended to take the yellow paint almost as easily as the purple. The angle grinder also overheats pretty quickly; I’d need to cycle through maybe four to be able to run continuous duty.

Purple paint stripped from schoolbus with heat gun and putty knife

Thursday night: Heat gun and putty knife. The heat gun softens everything and it’s hard to keep from scraping right down to bare metal, much less to leave the yellow paint.

Removing Van Rust

Rust cleaned off 1985 Chevy van with coarse wire wheel on angle grinder

Friday night: Coarse wire wheel on the angle grinder takes the rust right off my old van! Saturday morning: The rain puts the rust right back on! That’s okay; I can go back (Jack) and do it again, and it’ll take much less effort to get the light surface rust off than the heavy stuff that was there before.

Arly’s Advice

I just talked to Arly Funk, a wonderful gentleman who’s run a body shop in Newton all my life and will never retire; and he told me several things I don’t want to hear.

The original primer and paint are better than anything I’m going to be able to put on.

The house paint — even if not so sloppily applied — absolutely has to come off. It won’t adhere well enough for the next layer to last long.

Primer is not weather-resistant and is damaged by moisture. Anywhere I expose the primer, I need to reprime.

Anywhere I expose bare metal, I have about two hours to prime it. Beyond that, invisible oxidation is already forming and will weaken the bond between metal and primer. A light sanding with fine sandpaper is enough to clean this off before priming.

Out of curiosity, he has tested both hardware-store spray paint and roll-on liquid paint in his shop. Neither has good adhesion and longevity. In his experience, only liquid paint applied with a high-volume / low-pressure (HVLP) spray gun works well.


Serious Paint Removal Attempt #1: Too Fast!

Saturday, June 13th, 2009

Stripping paint down to bare metal

I got a 4″ disc wire brush for my angle grinder, thinking it would strip paint a lot faster than the cordless drill. It did — it stripped down to bare metal when I barely touched it to the bus!

I suspect the original primer is a lot better than anything I can buy, and certainly better applied, so I really don’t want to remove it; I want to leave the primer and maybe even yellow paint to cover with my own paint job.

If I did want to strip to bare metal, the brush I was using in the angle grinder would be great. For this job, I’ll see if I can find a finer brush for the grinder.

Also I need to find one with a 5/8″ arbor. Drilling a 1/2″ arbor out to 5/8″ causes separation of the metal plates formerly holding the wire pieces together. Careful application of the angle grinder’s arbor plates gets the wires held pretty securely — and remarkably concentric on the first try — but that’s no way to really do it.

Bus with a few linear feet of purple paint stripped

I switched to the “wire brush on a stick” in my corded drill and got a few linear feet of above-the-rail stripped. Took over an hour and it really wasn’t worth the effort.

Battery Compartment and AC Wiring

Bus battery compartment and AC wiring

I hadn’t leaned down far enough to really look in, so Jonathan was the original discoverer of the AC wiring sticking into the battery compartment. I’m guessing the former owner had an inverter installed in there — which I just read is a bad idea, as the battery acid fumes can eat up the delicate inverter guts. Maybe I’ll put mine in a separate compartment.

But What Will the Neighbors Think?

My neighbors saw the bus this afternoon for the first time. The folks next door think it’s really cool and a great idea. The man of the house from two doors down came over to say that “The Landing Strip” (painted on the front of the bus) is a bar in Aggieville (Manhattan), which gives a clue as to the provenance and likely former owner of the bus.

The best reaction was from the young couple across the street. As they were halfway across, they were already calling out that their curiosity had got the better of them; and they gushed about how cool the bus is and asked all kinds of questions. They let their four young kids explore the inside of the bus, and didn’t mind at all that they were enthralled by the dead baby mice. They’re all very enthusiastic about the project and the prospects and think it’s great!

This was, of course, before I backed into their mailbox, as one of the part-time police officers I don’t know came driving down the street.

Two Songs for the Bus

Sunday, June 7th, 2009

The Towing Song

Schoolbus bumper damaged by inappropriate towing

This is the way we tow our bus,
tow our bus,
tow our bus.

Schoolbus bumper damaged by inappropriate towing, close-up

This is the way we tow our bus
when we’re selling it in the morning
and we don’t care what happens to it any more

Schoolbus front bumper and frame

and it’s too hard to reach underneath and hook a chain around the frame.

Tra la!

The Paint Stripping Song

Purple house paint stripped from schoolbus

This is the way we strip the house paint,
strip the house paint,
strip the house paint.

Purple house paint stripped from schoolbus, closeup

This is the way we strip the house paint,
with a wire brush on a cordless drill

Purple house paint stripped from schoolbus fender

for a few minutes until the battery runs down
and the horrendous purple paint goes right away

Purple house paint stripped from schoolbus fender, closeup

and we are very happy.

Tra la!