Using just a chainsaw, a cordless drill, an angle grinder and a hammer, tree trunks straight from the forest can be turned into fantastic old world style rustic platforms such as decking and banquet sized table tops.
|Difficulty:||..........||You need to be able to use a chainsaw|
|Hazards:||..........||You need chainsaw training|
Step 1: Chainsaws and Tree Trunks
Before we start, just a quick word about chainsaws - they are probably the most dangerous hand tool you will ever use so make sure you get proper training in how to use them safely and wear the appropriate protective clothing, namely kevlar trousers, protective boots, face mask and ear deaf enders. Also, the chain mechanism should be well maintained and properly adjusted and the teeth should be sharp. Never start the chainsaw near the re-fuelling site or you might cause an explosion. The chain itself does not need to be a specialised rip chain for softwoods.
Now for the tree trunks. It's very difficult to find absolutely straight trunks and all the ones I used were slightly banana shaped due to the prevailing wind in the forest where they grew. My trees are western red cedar as this is easy to cut and very durable in the outside. Everything here is made from 4m long trees trunks.
The first step in construction, whether it be for decking or a table top, is to position the tree so that it bananas in the vertical plane as shown in the photo. Now it can be carefully sliced into 2 halves. Keep on slicing up tree trunks to produce as many sections as you need. This technique is not amazingly accurate, but it does give you an amazing rustic old world style finish which a bigger table based machine would not do.
Step 2: Line Up the Tree Slices
Now we have the components of an unusual puzzle which must be sorted and pieced together. Basically, the slices are placed on wooden bearers alternately top to tail and with the curves nestling in together with each other if this makes sense? If you have a load of bananas you could lay them on the table and they would fit together along the curved edges of one another. Same with the wood except they are top to tail as well. The photos dont really show this too well as it is quite subtle.
When the puzzle has been assembled, squash all the slices as tight together side to side and trim down between each slice with the chainsaw - technical name: "running the kerf". I'm sure this will make absolutely no sense to even the most seasoned lumberjack so let me explain further. The idea is to get the slices to fit together better and running the chainsaw down between the slices just trims off the points where the slices touch each other and not much more. Now the slices can be squashed back together again the process can be repeated until there is very little gap at all. See the second photo. Don't get too carried away as these structures actually require gaps between the sections to allow water to trickle through, but should not be so big that a dog could get it's paw stuck in, for example.
Step 3: Tie the Sections Together Using Battens and Screws
This is a temporary measure to keep the sections together whilst the whole structure is turned over. Get some friends to help you. Obviously, you don't need to do this if you're making decking as the sections are assembled in situ, using shims under the sections to get an overall flat result. The table top is different. The second photo shows the table top inverted.
Step 4: Cross Bracing
The cross bracing that I used is some pieces of beech that were pre-machined and I got cheap in a local auction. You could slice up some more tree trunks to get the same thing.
Position the cross braces across the table top and assess which bits of section need to be chiselled off the allow the cross brace to sit flush. No need to measure anything, it can all be done by eye. Start up the chainsaw and carefully carve out a shallow channel along the structure as shown in the photos.
Place the cross section in the channel and nail in with galvanised 4" nails at angles of 30 degrees. Repeat this a total of 5 times to get a nice secure platform.
Now spin the platform over and check for any petrooding nails, which should be ground off with an angle grinder before anybody steps on them.
Step 5: Trim the Platform Ends
Remove the battens and trim off the uneven tree slices at each end of the platform with the chainsaw.
Step 6: Test Drive the Table Top
Before inviting the neighbours around for home made cider, check that it works well with one person first. Get some feedback as to correct height, stability and taste.
Step 7: Have a Party!
Now invite the neighbours around to admire your handiwork and marvel at the fact that it was all done with hand tools.