ScottyT
Established Member
I managed to do a little bit more to my bridge last week, I’ll admit it was an especially great time. My focus are the main beams now, and I managed to get my planer that I have been restoring since March to a useable standard enabling me to run the main beams through it. The beams are very large for an outfit like us, and barely manageable with 4 men.
Rather obviously, they are a critical component of the build, carrying all 10 posts that in turn carry all the rails and lnfill work, as well as all the treads that fit directly to them.
They are 5.5 metres long, 115-120mm thick and 605mm wide. My Wadkin FM planer will thickness to a maximum width of 615, so these are absolutely on the limit.
We set my planer up in the middle of the yard, Al fresco style, for a number of reasons, main one being the uninhibited access of simply forklifting the beams in place, running them through with (relative) ease, then repeating, another reason was the extraction was of the open air variety, being green oak you don’t get dust just a really nice large shaving, so with the bridge guard removed (don’t try this at home style) the chips were allowed to fly out the gap between the beds unobstructed clearing my cut and producing a superb finish. A total of 2 passes each taking 6mm off a time achieved the results I was after, a glass smooth finish and the performance of the Wadkin exceeded all expectations, incredibly powerful the motor didn’t even change tone.
It’s worth noting this planer has a very special block, it’s a two knife set up and the knives are skewed, producing a shear cut that is a pleasure to use (imagine hand planing it’s the difference between going head on with the tool or planing at an angle) it’s the small details that make the biggest difference.
That’s one big slab of timber. We estimated in excess of 200kg’s, these were £900 each, obviously a spare isn’t in the equation so care must be taken whilst machining etc.
above is a photo of the finished article, ready for my template to be offered up and start cutting.
I laid up one side of my bridge, cramped it up exactly on my rod and offered the large beam template up where it needed to be, I then cut my plumb and seat cut on it directly off the side of the bridge via the rod, this now gives me my 1:1 for the main event.
It’s looks a little something like this, this beam was longer than the other, I left it on though as it’ll come in for post caps, as will the huge off cuts in the middle.
I draw around this with a pencil, and need to cut it out leaving around 2-3mil for facing up. I have a Mafell portable bandsaw, which is an incredible tool that I’ll demonstrate in the next thread, but the max throat cut is around 200mm, meaning I would have to take multiple cuts into that big middle offcut to get to my line, I don’t want to do that so I rough it out with my trusty Husky, getting me to with an inch of the desired cut line, it’s then I can use the bandsaw to get a lovely cut ready for machining.
Marking all the way around with a pencil ready for the chainsaw.
Cutting around it very roughly with the chainsaw to get my initial curve, wanting to avoid a Wallace and Gromit style scene of cutting through the trestles as well as the workpiece.
I’ll leave it there for now and do another update next week.
Scotty
Rather obviously, they are a critical component of the build, carrying all 10 posts that in turn carry all the rails and lnfill work, as well as all the treads that fit directly to them.
They are 5.5 metres long, 115-120mm thick and 605mm wide. My Wadkin FM planer will thickness to a maximum width of 615, so these are absolutely on the limit.
We set my planer up in the middle of the yard, Al fresco style, for a number of reasons, main one being the uninhibited access of simply forklifting the beams in place, running them through with (relative) ease, then repeating, another reason was the extraction was of the open air variety, being green oak you don’t get dust just a really nice large shaving, so with the bridge guard removed (don’t try this at home style) the chips were allowed to fly out the gap between the beds unobstructed clearing my cut and producing a superb finish. A total of 2 passes each taking 6mm off a time achieved the results I was after, a glass smooth finish and the performance of the Wadkin exceeded all expectations, incredibly powerful the motor didn’t even change tone.
It’s worth noting this planer has a very special block, it’s a two knife set up and the knives are skewed, producing a shear cut that is a pleasure to use (imagine hand planing it’s the difference between going head on with the tool or planing at an angle) it’s the small details that make the biggest difference.
That’s one big slab of timber. We estimated in excess of 200kg’s, these were £900 each, obviously a spare isn’t in the equation so care must be taken whilst machining etc.
above is a photo of the finished article, ready for my template to be offered up and start cutting.
I laid up one side of my bridge, cramped it up exactly on my rod and offered the large beam template up where it needed to be, I then cut my plumb and seat cut on it directly off the side of the bridge via the rod, this now gives me my 1:1 for the main event.
It’s looks a little something like this, this beam was longer than the other, I left it on though as it’ll come in for post caps, as will the huge off cuts in the middle.
I draw around this with a pencil, and need to cut it out leaving around 2-3mil for facing up. I have a Mafell portable bandsaw, which is an incredible tool that I’ll demonstrate in the next thread, but the max throat cut is around 200mm, meaning I would have to take multiple cuts into that big middle offcut to get to my line, I don’t want to do that so I rough it out with my trusty Husky, getting me to with an inch of the desired cut line, it’s then I can use the bandsaw to get a lovely cut ready for machining.
Marking all the way around with a pencil ready for the chainsaw.
Cutting around it very roughly with the chainsaw to get my initial curve, wanting to avoid a Wallace and Gromit style scene of cutting through the trestles as well as the workpiece.
I’ll leave it there for now and do another update next week.
Scotty
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