This question 'How do I bend wood and plywood' is one that used to come up quite often,its a marine trade thing from my side but also a furniture thing,from my many years as a proffesional shopfitter.The bending of ply woods became easy once we started importing the specially made Superform bendable plys,available from 3mm to 16mm thicknesses but we just stock the 3mm,5mm and 8mm ones, as they can be added together to make most combinations and either grain direction.The days of reading a boat builders descripition of Tortured Plywood Construction are now long gone and when you use Superform Bendable Ply,at least your certain of it being water proof and not just simply moisture proof.
Bending wood is a different matter,not all species are happy to be bent,Mahogany and Teak come to mind but Ash,Oak and Beech seem to revel in the treatment.Steaming is the normal route to those doing a traditional method boat building construction and Oak is always going to be the species of choice,all you need is a metal pipe or tube closed one end,as long as the wood stock you have and a little more,you then need a slow fire at one end,enough water in the tube to boil it and with the tube set up on an angle,20 degrees will be good,you just cook the wood untill its soft enough to shape to your required form? Green steamed Oak,can be shaped to the most amazing profiles while it is hot,once fastened,then dried out,which will mean cured and seasoned,it will be as hard as nails and quite unable to move,perfect for frames on boats of course,we have the bronze fasteners and copper roves,should you need them.
What many will not tell you is the wood should be 'green' this is a term used in the trade for wood which is 'wet off saw' or close enough,wood is full of sap when the tree is felled, it is normally sawn in this condition,it will then be taken to dry out,pin stacked,either air dry which is slow,or Kiln Dried,which is many times faster and can be taken to a given moisture content,around 12% to 14% is normal.
Compress Wood, this is another method I have followed with great interest,we have had many samples,such as the one in the picture,that sample is real wood,its not a plastic copy,it has been twisted into shape and allowed to dry,which then leaves it as you see, I have never seen it in use in South Africa but I suspect its well known in Europe where it was invented and then developed. Compress Wood,the name says it all but you would never actually guess what it means? Stock of timbers as mentioned before are selected for quality of grain and no knots,sawn wet to a stock size,it is then steamed in an enclave,then removed and placed in a hydraulic press,simple stuff really,its a ram one end of the support bed which compresses the wood from one end,the takes it 20% under its original length,some of which will spring back when the pressure is removed. The wood has now reached a point when it can be bent,the reason being it has had all its internal tubes smashed,those tubes normally carry the trees water or sap,they are also responsable for the strength of the species.If the Compress Wood is to be used right away,it can be taken to the shaping jig and moulded,if it will be put into stock,it will be vacume packed and made ready for use later,sold in regular sizes,its and easy task to make the most complicated shapes!
Roy
Bending wood is a different matter,not all species are happy to be bent,Mahogany and Teak come to mind but Ash,Oak and Beech seem to revel in the treatment.Steaming is the normal route to those doing a traditional method boat building construction and Oak is always going to be the species of choice,all you need is a metal pipe or tube closed one end,as long as the wood stock you have and a little more,you then need a slow fire at one end,enough water in the tube to boil it and with the tube set up on an angle,20 degrees will be good,you just cook the wood untill its soft enough to shape to your required form? Green steamed Oak,can be shaped to the most amazing profiles while it is hot,once fastened,then dried out,which will mean cured and seasoned,it will be as hard as nails and quite unable to move,perfect for frames on boats of course,we have the bronze fasteners and copper roves,should you need them.
What many will not tell you is the wood should be 'green' this is a term used in the trade for wood which is 'wet off saw' or close enough,wood is full of sap when the tree is felled, it is normally sawn in this condition,it will then be taken to dry out,pin stacked,either air dry which is slow,or Kiln Dried,which is many times faster and can be taken to a given moisture content,around 12% to 14% is normal.
Compress Wood, this is another method I have followed with great interest,we have had many samples,such as the one in the picture,that sample is real wood,its not a plastic copy,it has been twisted into shape and allowed to dry,which then leaves it as you see, I have never seen it in use in South Africa but I suspect its well known in Europe where it was invented and then developed. Compress Wood,the name says it all but you would never actually guess what it means? Stock of timbers as mentioned before are selected for quality of grain and no knots,sawn wet to a stock size,it is then steamed in an enclave,then removed and placed in a hydraulic press,simple stuff really,its a ram one end of the support bed which compresses the wood from one end,the takes it 20% under its original length,some of which will spring back when the pressure is removed. The wood has now reached a point when it can be bent,the reason being it has had all its internal tubes smashed,those tubes normally carry the trees water or sap,they are also responsable for the strength of the species.If the Compress Wood is to be used right away,it can be taken to the shaping jig and moulded,if it will be put into stock,it will be vacume packed and made ready for use later,sold in regular sizes,its and easy task to make the most complicated shapes!
Roy
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