Hello All!
I hope this is in the correct place on the forum list. It seems like a general fix-up topic. It's about DIY wood hardener & filler.
Since wood hardener is so expensive, I sought out alternatives and, after much experimenting, discovered some successes that I would like to share.
Wood hardeners are usually a plastic of some sort dissolved so that the liquid is very thin and will penetrate wood fibers, sealing them against moisture and stiffening them for repairs. Store bought wood fillers are usually either wood flour mixed in a binder, epoxy glue or auto body fillers.
The successes were tested on pine, fur, balsa, cardboard, fiberboard and even paper. One of each test piece was soaked underwater for several days and compared to the un-soaked control sample for water resistance and stiffness.
General Items For Safety & Success:
Work Outdoors & keep pets & children away from the Not Earth or Lung Friendly options.
Read & Understand the safety requirements in the Material Safety Data Sheet for each component (MSDS or SDS)
Wear ear, eye, skin and lung protection.
. (Lungs need the proper cartridge in your well fitted respirator. Dust masks not allowed!)
Let the wood dry completely before proceeding.
Optional: Bleach the wood to kill mold spores & let it dry.
Optional: Copper Sulfate painted on the wood will prevent mold from growing should moisture enter from
. the un-treated side. Let it dry before putting the hardener.
Not Earth or Lung Friendly, But Similar To Store Bought: Fast Drying
Put acetone in a glass or metal jar with a tight sealing metal lid. (A plastic jar will melt.)
Cut up a plastic container that is made from polyethelyene terephthalate PETE plastic. (Number 1 will be on the recycle code symbol).
Water & pop bottles are usually this material. Check the 3-Arrow symbol on the plastic for a "1".
Insert the cut up plastic pieces into the acetone until it can dissolve no more. This is called a "saturated solution".
It may take many minutes for the plastic to dissolve.
Remove the last piece that could not dissolve.
Now you have good wood hardener that is similar to the store bought! It absorbs very well into the dry wood & dries hard & somewhat brittle.
Not Earth or Lung Friendly Version Two:
Polystyrene (Recycle number 6), commonly called "styrofoam" melts much faster than the PETE and is fun to watch.
The non-corn starch packing peanuts work great.
Result? Same absorbancy in wood and same water proofing. But, the final piece is not as stiff or brittle as with PETE.
Dry Time before testing was 7 hours for each the PETE and the polystyrene samples.
Earth & Lung Friendly:
Type 1 PVA glue, such as Titebond III diluted 50:50 with white vinegar. Simple & quick!
Result: It absorbs very well into the dry wood, paper, etc. Water beads up on it. Soaked paper coated with this did not dissolve. (Dry time was 17 hours before testing.)
Paint adheres better than when painted directly on the plastic wood hardeners above.
The negative is that the wood is not as hard to the touch as with the melted plastic. Perhaps this slight flexibility makes it better for items that heat and cool, such as sun drenched siding.
WOOD FILLER- Not Earth & Lung Friendly: Very Fast Drying
The "Go To" for wood repairs is often body filler (AKA Bondo). Most are not waterproof. Water won't wreck them, but will go through tem if not painted. They can be a bit hard to paint without scarfing and sometimes using an etching primer. White filler with white hardener make painting a bit easier. Of course, these are hard on the earth & lungs.
I used Advantage brand #801 for testing. It's about 29.00 USD per gallon and easy to sand. For waterproof filler, I used Duraglass. It is harder to sand and costs more, but is 100% waterproof.
WOOD FILLER- Earth & Lung Friendly:
No pre-mixed wood fillers that I found are waterproof, so I tried to make one as close to waterproof as possible.
The Experiment was Durham's Water Putty, but mixed with 50:50 Type I PVA glue and white vinegar. Dry time was 16 hours before torture testing.
The test bowls at 1/4" thick putty that I made did not dissolve when soaked for 2 days underwater, but the surface could be scratched with a fingernail. Water left in the bowls overnight did not wick through to the paper that the bowls sat upon.
After painting the "test dummies", they did not get at all soft when soaked. Although harder to sand than body filler, Durhams paints like a dream with latex! Also, it can be mixed to whatever consistency works best for your project.
I hope these ideas will help you with a project or two!
Paul
I hope this is in the correct place on the forum list. It seems like a general fix-up topic. It's about DIY wood hardener & filler.
Since wood hardener is so expensive, I sought out alternatives and, after much experimenting, discovered some successes that I would like to share.
Wood hardeners are usually a plastic of some sort dissolved so that the liquid is very thin and will penetrate wood fibers, sealing them against moisture and stiffening them for repairs. Store bought wood fillers are usually either wood flour mixed in a binder, epoxy glue or auto body fillers.
The successes were tested on pine, fur, balsa, cardboard, fiberboard and even paper. One of each test piece was soaked underwater for several days and compared to the un-soaked control sample for water resistance and stiffness.
General Items For Safety & Success:
Work Outdoors & keep pets & children away from the Not Earth or Lung Friendly options.
Read & Understand the safety requirements in the Material Safety Data Sheet for each component (MSDS or SDS)
Wear ear, eye, skin and lung protection.
. (Lungs need the proper cartridge in your well fitted respirator. Dust masks not allowed!)
Let the wood dry completely before proceeding.
Optional: Bleach the wood to kill mold spores & let it dry.
Optional: Copper Sulfate painted on the wood will prevent mold from growing should moisture enter from
. the un-treated side. Let it dry before putting the hardener.
Not Earth or Lung Friendly, But Similar To Store Bought: Fast Drying
Put acetone in a glass or metal jar with a tight sealing metal lid. (A plastic jar will melt.)
Cut up a plastic container that is made from polyethelyene terephthalate PETE plastic. (Number 1 will be on the recycle code symbol).
Water & pop bottles are usually this material. Check the 3-Arrow symbol on the plastic for a "1".
Insert the cut up plastic pieces into the acetone until it can dissolve no more. This is called a "saturated solution".
It may take many minutes for the plastic to dissolve.
Remove the last piece that could not dissolve.
Now you have good wood hardener that is similar to the store bought! It absorbs very well into the dry wood & dries hard & somewhat brittle.
Not Earth or Lung Friendly Version Two:
Polystyrene (Recycle number 6), commonly called "styrofoam" melts much faster than the PETE and is fun to watch.
The non-corn starch packing peanuts work great.
Result? Same absorbancy in wood and same water proofing. But, the final piece is not as stiff or brittle as with PETE.
Dry Time before testing was 7 hours for each the PETE and the polystyrene samples.
Earth & Lung Friendly:
Type 1 PVA glue, such as Titebond III diluted 50:50 with white vinegar. Simple & quick!
Result: It absorbs very well into the dry wood, paper, etc. Water beads up on it. Soaked paper coated with this did not dissolve. (Dry time was 17 hours before testing.)
Paint adheres better than when painted directly on the plastic wood hardeners above.
The negative is that the wood is not as hard to the touch as with the melted plastic. Perhaps this slight flexibility makes it better for items that heat and cool, such as sun drenched siding.
WOOD FILLER- Not Earth & Lung Friendly: Very Fast Drying
The "Go To" for wood repairs is often body filler (AKA Bondo). Most are not waterproof. Water won't wreck them, but will go through tem if not painted. They can be a bit hard to paint without scarfing and sometimes using an etching primer. White filler with white hardener make painting a bit easier. Of course, these are hard on the earth & lungs.
I used Advantage brand #801 for testing. It's about 29.00 USD per gallon and easy to sand. For waterproof filler, I used Duraglass. It is harder to sand and costs more, but is 100% waterproof.
WOOD FILLER- Earth & Lung Friendly:
No pre-mixed wood fillers that I found are waterproof, so I tried to make one as close to waterproof as possible.
The Experiment was Durham's Water Putty, but mixed with 50:50 Type I PVA glue and white vinegar. Dry time was 16 hours before torture testing.
The test bowls at 1/4" thick putty that I made did not dissolve when soaked for 2 days underwater, but the surface could be scratched with a fingernail. Water left in the bowls overnight did not wick through to the paper that the bowls sat upon.
After painting the "test dummies", they did not get at all soft when soaked. Although harder to sand than body filler, Durhams paints like a dream with latex! Also, it can be mixed to whatever consistency works best for your project.
I hope these ideas will help you with a project or two!
Paul
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