Stripping paint

pklonowski

Unrepentant Canoeist
Okay, I finally have some time today to start using the methylene chloride (not enviromentally safer) stripper on my 1919 Old Town. HOLY CATS! The difference between the safer stuff and this slop is incredible... one application, wait 3 minutes, & I could scrape paint off all the way to the wood, through however many layers of paint are on this canoe.

It took 2 & 1/2 gallons of safer stripper (three flavors, none worked better than the others), and a lot of hours, to get almost 1/3 of the canoe mostly stripped (still have some parts to finish up). The meth chloride took maybe a cup, and maybe 20 minutes, to strip the width of 4 ribs down to nearly bare wood.

There were a couple of persistent paint spots that the safer stripper could not remove, even after six applications. After one application of the less safe stuff, they are gone.

Using either the safer or less safe stripper, the removed material is still toxic waste, because of the lead content of the old paint. With the less safe slop, there's a lot less of this waste, because there will be so much less stripper needed.

The fumes for the less safe slop are horrendous, but a slightly open garage door, and a good organic vapors mask, takes care of that.

I'm sold. Although the place in Green Bay is still a viable option...
 
I spread the paint/varnish glop onto an old newspaper, and let the chemicals evaporate. I then feel better about putting the dried up sludge in the trash. It does say that it is water neutralizing, so when I rinse the hell out of the canoe afterwards, I don't feel too bad about the flow hitting the sewer system. I try and minimize that when I can. The yard loves the water! I only strip in the summer though, and it usually evaporates in pretty short order.
 
“The fumes for the less safe slop are horrendous, but a slightly open garage door, and a good organic vapors mask, takes care of that.”

Most of these strippers are Methylene chloride based. The way I understand it, is this is the nasty stuff you should be protecting yourself from (among other things). Last time I checked there is no vapor cartridge on the market that protects you from this chemical. The only way to fully protect yourself from inhaling it is to have a full face mask that brings air in from a separate location other than were you are using the paint stripper.

It is important to remember that when wearing organic vapor masks that just because you can’t smell it, does not necessarily mean you are being protected from it. I know from experience that when wearing such a mask around this type of stripper you can’t smell it so it is easy to assume you are being protected.

3M has a bomber help line for this type of thing. The last time I spoke with them about this issue they told me that if you are us using a vapor cartridge to protect yourself from Methylene chloride, you might actually be breathing in a more concentrated dose and you are probably better off not wearing a mask at all despite the smell.
 
Reason is because of the Definition

The reason that organic vapor cartridges are not approved for use with methylene chloride is that methylene chloride is a "known carcinogen". Since the chemical is proven to cause cancer (in laboratory animals), NIOSH and others have indicated the only safe means of protection is a supplied air system to rule out any exposure. Organic vapor cartridges will strip methylene chloride, but they simply are not as effective as positive pressure and supplied air. The rules were also written for occupational settings to protect workers and no exposure to a known carcinogen is achievable and the way to go.

Actually, NIOSH has an easy to use website that provides the protection necessary for many chemicals (respiratory, gloves etc.). It is a very handy reference and is on-line here:

http://www.cdc.gov/niosh/topics/chemical.html
 
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Yikes! So that line on the can about "proper ventilation" gets the Understatement of the Year Award. V&L Stripping in Green Bay sounds better all the time. And they'd probably be happy to take the rest of this stuff off my hands, too...
 
Much more detailed info than is on the can.... While my exposures have been fairly short (max 30 minutes), they were repeated at short intervals yesterday. I didn't experience any symptoms, which I would have recognized as being similar to those I experienced way back when I worked in a cabinet shop... and had to stay away from the finishing booth. Anyway, a lot of paint got removed quickly, but I think I'll let the pros do it in the future.

Thank you for the link!
 
I'm restoring a canoe whose interior has been painted multiple times over the last 70 years with a mixture of different types of paint.

Here are some lessons I've learned using methylene chloride strippers, but I still need more help.

1. Don't try stripping unless the temperature is above 60 degrees. (I got this one in a phone conversation with Rollin. Thanks Rollin.)
2. Apply plenty of stripper. Literally, flood the surface. Turn the canoe on it's side when doing the sides so you can work horizontal surfaces.
3. Cover with foil or plastic to keep the stripper from evaporating too fast.
4. Wait at least 40 min. I don't care what the can says!
5. Work in small sections. I've been taken two ribs sections at a time.
6. Once you scrap off the sludge, keep the surface wet with more stripper until you've worked through all of the layers. It is taking me four applications on each section.
7. Before moving on, clean up the section with a stiff brush and mineral spirits. Otherwise the paint residue just hardens and you have to go back and start over.
8. Some brands work better than others. I've tried two different brands with vastly different results.
9. A lot of sanding is still required.

Anyway, that's my experience, but it's still very slow going. I've come close to giving up and just repainting the interior many times and may still get to that point.

Anyone see anything I'm missing or could do better?

BTW, I limit my sessions to about two hours. More than that I start to get light headed. I really need to work indoors where it is warm, but I haven't because of the vapors.
 
You might want to consider working in shorter sessions... like, quit before you get light-headed, or any other symptoms kick in. Usually symptoms mean bad things have happened already...
 
There is no free lunch!!!!!!!!!!!!!! Stripper that will remove paint MUST have a methylene chloride base. If you cannot get a pro to strip your canoe, then get 3 gallons of water wash methylene chloride base stripper along with a nylon snow brush for under the gunnels and up in the ends and an iron shaped nylon brush for the main body of the canoe. You will also need some hot water and TSP or its substitute. IFFFFF you can control the pressure on a high pressure washer that uses hot water and soap that will work even better. Steel putty knives will put marks in the cedar planking that will NEVER, EVER come out. ( I know that's a long time.)
It is possible to strip the entire canoe at once, but most people would feel more comfortable just doing one side. Apply the stripper. Apply it again. Apply it again. Go do something. Come back and apply more stripper. ONLY when all of the paint and the varnish have bubbled, brush the residue. Apply more stripper. Wait some more. Apply more stripper if necessary. AFTER ALLLLL of the paint and varnish have bubbled, With the nylon brushes scrub the stripped area with HOT water and TSP, or use the pressure washer on LOWWW pressure. Dispose of the runoff properly; whatever that means . For one or two canoes that might not be a problem.
 
Any advice on doing it inside? It's too cold for the stripper to work outside and I'm concerned about ventilation inside. I have it in an unfinished "walk-out" basement with plenty of windows. (Fortunately, it has it's own central heat separate from the house.)

Do I just open a couple of windows?
 
I would not recommend doing it inside. Occasionally, I will strip some small parts inside the shop, but not an entire canoe.
 
I'm stripping my canoie in the heated garage, with the door cracked open. But I'm doing it in small sections, not all at once. I'm probably not out there more than 30 minutes at a time, and am adjusting the surface area that I'm working on to accommodate that.
 
If you have no choice but do it inside a garage or house and you dont want to wait, put the room you are working in under negative pressure. Its a technique we use all the time for mold remediations, asbestos abatement and so on. It requires an air scrubber or large enough fan to draw air from the sealed up room and exhaust it out through a door or window. Attached is a typical set up, blue foam in a widow works well. You need to poly off any hvac vents, and doors and windows. I wont go into huge detail, its all over the web and you could likely rent a machine either from a restoration contractor or rent-all place. You will still need to take normal precautions for your own safety within the room but you will lessen the effects over the rest of the building. It will require that you educate yourself to do it effectively, but it works wonders for lots of applications, even fumes when painting a room of the house. As Gil said, there is no free lunch; but the cost of a day or so rental of a machine for a safe set up is a lot cheaper than a new set of lungs.
 

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I wonder if you could use a cpap machine (set up outside the stripping area) with a long hose to supply clean air while stripping either inside or out. I agree with all its a nasty business, I have done 3 so far this year, and there is no free lunch.
 
I don't know what everyone is worried about. I always look forward to stripping day because I get to dress up in my best outfit. Who doesn't feel good when they look good!
stripping13.jpgstripping13.jpg
 
A cheap and easy way to get negative pressure in a room is to hook up a furnace squirrel blower and exhaust through a window by a fabric sleeve.
 
Rollin, That's what I use to clean the cats' litter box. I never thought to use it stripping canoes. THANKS... Mike.....
 
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