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Posted by - Clayton707
Post date - 01-30-2007, 09:31 PM
I have heard several modelers say that soaking wood in ammonia helps with the bending process. What do people here think? I am now cutting out deck beams for my Wasa model and was thinking of soaking them with ammonia prior to bending them with my deck frame jig.

If it does work, how long should I soak them? They are 1/4 of an inch by 3/8th of an inch on average but vary a bit like every thing else on the Wasa.

Thanks in advance for the advice everyone! :coffee:


Posted by - hamdul
Post date - 01-30-2007, 11:20 PM
I have quite a bit of experience bending wood, bending Appalachian dulcimer sides which are a scant 1/8" thick. They can be walnut, cherry, rosewood, Birdseye maple. I have always used Water to moisten the wood. The idea is to get the cells wet then when heat is applied the water turns to stam and softens the cellular structure. I assume that your wood is one of the soft woods and I also assume that there is not much of a curve that being the case and the size is small enough so that bending should be no problem. Just go slow and let the curve occur at it's own rate.

Posted by - leecoate
Post date - 01-31-2007, 07:16 AM
I have also had discoloration with ammonia. My experience is limited, but I theorize that the ammonia breaks the surface tension of the water allowing it to penetrate at a faster rate. I have had good results with small amounts of vinegar and the smell is not quite so bad-Lee

Posted by - Clayton707
Post date - 01-31-2007, 07:22 AM
Thanks everyone. I will try soaking them in vinegar. I like how the effect of ammonia on wood sounds but I dont like how it may become discolored!


Posted by - TommyMeisel
Post date - 01-31-2007, 03:52 PM
Ask any furniture maker or restorer what he uses to bend wood and he will tell you water/steam/heat. Not ammonia. Where this came from is a mystery, but I have heard it for almost 70 years now. If you want to bend the wood, soak it in hot water, and then steam it or heat it in the microwave.

All the ammonia will do is clear your sinuses.

Posted by - wirewolf
Post date - 01-31-2007, 04:03 PM
...furniture maker or restorer what he uses to bend wood and he will tell you water/steam/heat.............If you want to bend the wood, soak it in hot water, and then steam it or heat it in the microwave...ammonia will do is clear your sinuses.Amen! Wet towel wrapped around the strips, into the ole microwave! Got one from a friend and have it right in my shop.
Experiment with the timing though. First time I tried it I wound up with baked wood strips, al la carte! #-o
Save the ammonia for cleaning and the vinegar for salads :chew:

Posted by - Clayton707
Post date - 01-31-2007, 04:49 PM
Now I have changed my mind. Im going with the microwave method at least to try it first! I think that the place the ammonia theory came from is that they do use ammonia to bend wood in industrial settings under very high pressure and heat. Something we cannot do in our own homes! This is what I found while searching online.

Thanks everyone!

Posted by - flywater
Post date - 02-01-2007, 07:06 PM
The idea of soaking wood in straight ammonia may have come from the fuming process, used in the early 20th century to color wood. I have found that using windex accomplishes the same thing, allowing the wood to bend easily, but does not haver the draqback of affecting glue adhesion/penetration or thinning. If you are using a water based glue, you drying times will increase quite a bit. If using CA, the windex does not affect the adhesion properties of the glue. I have also found that the windex, even though it contains ammonia, does not discolor the wood. Be careful in trying extreme bends though, ie the bow or stern, as the wood fibres will still tend to split as teh wood is bent around the frames or forms. Good luck!

Posted by - TommyMeisel
Post date - 02-02-2007, 01:55 PM
Ammonia was used to darken oak about 100 years ago, and Stickley is the most remembered as a supplier of fumed oak furniture.

The wood is enclosed in an airtight tent or room, and exposed to the fumes from industrial ammonia, usually overnight. Ammonia fumes will darken wood with a high tannin content, and oak is the most common fumed wood. The ammonia is dangerous to work with, and this method of darkening wood is seldom done anymore except by hobbyists or restorers. The ammonia causes an oxidation of the tannin in the wood, the same thing that happens naturally over many, many years.

You can do this yourself, but it is dangerous to work with industrial ammonia (anyhydrous ammonia), so a strong commercial cleaning ammonia (25% dilution) should be used. Make yourself an airtight container, put the wood in it so that all surfaces to be darkened are exposed, then put the ammonia in a shallow dish inside. Don't use aluminum, the ammonia will eat through it. When the wood has reached the color you want, take it out. Use of a gas mask is recommended!

Now, if you want to bend this wood, steam it!!

Posted by - Clayton
Post date - 02-03-2007, 10:15 PM
This is an interesting discussion. I had never thought of soaking and microwaving the wood for steam bending. I have often thought of building a steamer for (larger) woodworking projects, but a smaller one could be made for planking.

The benefit of building a steamer is that you could steam longer pieces than those that fit in a microwave. All you would need is some pvc pipe and an old electric coffee pot (the kind with a round spout. It is easy to do, as long as you take a few basic safety precautions to insure that pressure does not build up in the pvc steaming chamber. Clayton, I have a couple of articles from woodworking magazines if you would like to see them some time.

Funny, Tommy stole the words right out of my mouth. As I began to read this thread I thought of all Arts & Crafts/Craftsman furniture that was darkened using ammonia. But like he said, high tannin woods are going to stain more. So you may not have much staining with some species.


Posted by - Clayton707
Post date - 02-04-2007, 10:00 AM
I am going to try heating my deck beams in the microwave after they have soaked in water for a few days. When I made smaller dimension deck beams on my other models, I would just soak them in water for awhile and then transfer them to the deck beam jig with no heating. They would come out bent with no spring back after having them in there for a few months. I think heating them, however, would help with the bending process especially with the larger dimension beams that I have to deal with.

My wife is replacing our old microwave so I am just going to use that one. It is big enough to fit 11" stock in.


Posted by - neptune
Post date - 02-04-2007, 10:48 PM
G'day Clayton, I posted a reply about plank bending, here it is again, I use a coffee perculator it is about 10"-12" high I took the perculating part out just leaving the element in the bottom, fill it 7/8 full with hot water and when you plug it in it boils in no time, I used it on my model of the Royal William and it handled 6mm-8mm-10mm timber no problems, best of luck, regards John.
PS I was thinking of building something bigger but I have used this for about 10 years and had no need to go bigger.