garage doors

[drdoor 14]

Hello

I am just learning about refinishing garage doors. I have to bid on refinishing 3 single rough sawn alder garage doors that have a semi transparent sealer on them. The bottoms are weathered as well. I tried to post pictures but could not seem to achieve the task at hand. It looks like they need to be stripped before anything else. I have a small residential power washer and have applied finish to garage doors before. Any help would be appreciated. This is in the scope of a very large project which involves MANY alders doors which I will refinish, so I would like to have an answer for the garage doors as well.

I am providing a link to my picasa web albums which has the garage doors

Picasa Web Albums - puulboy - garage doors#

thanks

Don

[Beth n Rod 1,279]

Those doors are potentially stunning, makes me want to see the rest of the house.

I would strip them with HD-80, then neutralize them with a blend of Oxalic and Citric acids, prep them ( light buffing or sanding) and then seal them. Reduce the pressure you are washing with to 1000 PSI at the tip, and remember it is not the PWer but the chems doing your work so dwell time is key. Don't wash until the wood is ready.

Beth :cup:

[RPetry 564]

Don,

Nice doors, although the width looks a bit narrow for a car.

Wood contractors here on TGS generally use sodium hydroxide based strippers to remove oil based stains. That is your first determination, the type of stain on the doors. Most semitrans exterior wood stains are oil based, usually linseed oil, but over the past several years water based stains have become more prevalent.

Check the banner ads here on TGS. ACR Products, The Sealer Store, Extreme Solutions, Inc., and Sun Brite Supply all provide NaOH based strippers, as well as citric, oxalic, or a combination of acid used as brighteners/neutralizers.

These strippers come in powder form so you may adjust strength. Mix up a quart of water with 2 oz. first. This would be the equivalent of 8 oz. per gal.. Apply to a door area with the most intact stain and let dwell for 5 minutes or so. Scratch the surface with a mixing stick to see if the old finish easily comes off. If so, you may want to halve a new mix to 1 oz. or 4 oz. per gal. equivalent and reapply on another area. The trick is to use the lightest effective mix to keep down firring or raising of the grain. You can also increase dwell time of the stripper before washing, 20 minutes or so is reasonable. But you must keep the stripper wet on the wood, either by applying more, or misting with water from your pressure washer.

As Beth stated, let the stripper do the work. A pressure washer for wood is little more than a glorified rinser. Low pressure with lots of water will help keep the firring of the wood down.

After stripping, apply your acid. This will help neutralize any remaining sodium hydroxide and also brighten the wood. Most rinse the acid off after 10 or 15 minutes.

Stain selection is varied. We all have our favorites, and there is a lot of information here about different exterior wood stains.

The vendors listed above can help in mix concentrations and process. Feel free to call or email me if you need additional assistance.

[James 624]

Make sure you do a test spot to determine if the stripper will work. I have done many Garage doors and you will run into stuff that will not come off.

[drdoor 14]

Thanks for all the details everyone. A few questions.

How does the stripper and neutralizer get applied? hudson sprayer??

What kind of protection do I need for surrounding brick and driveway.

when the suggetion of sanding or buffing was give.... Is that something I can do with a nylon brush?/ since these are rough sawn?

Forgive me for my ignorance , This is the very first part of my investigation.

I have added some pictures, to the link, so you can at least see the rest of the doors involved. There are actually multiples of each type in the pictures. I may be there awhile.

Picasa Web Albums - puulboy - garage doors#

thanks

Don

[RPetry 564]

Don,

A pump up type sprayer will work for both stripper and acid application.

If the stripper concentration is not to hot, flooding the surrounding brick with water should be fine, rinsing as needed. Same with driveways, but more care should be given if asphalt.

The wood will probably fir a little bit from the stripper. With the detail windows/doors from your pictures, a light buffing with a Makita 9227C or similar and special 3M pads (ACR Products carries them) would probably be faster than a nylon or fine wire brush.