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Friday, June 25, 2010

Cutting Outline for 'Cariad' Welsh Lovespoon

Ripping Down the Block on the Band Saw

With the piece of european cherry sawn to the right dimensions, it is time to cut the outline on the scroll saw. A hand fret saw could be used but even with a scroll saw it would be heavy going with a piece of cherry nearly an inch and a half thick.

Heavier going than I thought, because ripping down the block to a thickness the scroll saw could manage and yet still have it thick enough for carving options, resulted in a slightly curved cut from the band saw that I couldn't afford to level without losing desired thickness.

The surface that I attached the pattern to, with spray adhesive, had been planed smooth and straight. The sides were also dressed square with the face. This is worth doing if possible for
a deeply layered carving like this, because it can make some things easier. The uneven face off the band saw, that would now rest on the scroll saw table however, was now not going to make cutting easy.

The one side of the outline was cut successfully even though with less ease than could have been. Surprisingly it only took three blades and only one of those was an actual breakage. During the next session cutting the other side of the outline, I replaced the blade, that I thought would be very dull by now, and started cutting.

Progress was incredibly slow... Could it be that the cherry was even denser in this area of the board ? Or is there a variation in the cutting effectiveness from one blade to another, even of the same type ?.. No and yes... (sort of). The blade you put in back to front, does in fact cut less efficiently than another of the same type!

Another tip is; don't mistake persistence with
sheer unthinking stubbornness, there might be a reason why things don't go as expected other than 'the tools or materials have somehow changed'.

The blade, with brutal force, was made to 'cut' through nearly an inch of, and inch and a half thick board of cherry, with no more teeth available than a rooster, before I decided to change the blade.

Well change it around anyway. I reinserted the now banana shaped blade and continued to cut about half the other side before the 'Flying Dutchman' brand penguin silver#5 blade finally broke. – Are these blades tough or what ? – The rest of the cutting went well.

Half the Outline Cut and the Spoon Profile Marked Out

Having squared the sides, facilitated the laying out the profile of the spoon on one side, which could then be cut off in one piece and used, both as reference and for reassembling the block, prior to cutting and shaping the profile of the spoon. Squaring the sides also makes it easy to gauge lines parallel to the edge, just by gripping a pencil tightly a certain distance from the edge and spacing it with the position of other fingers sliding against the other face as you slide your hand along. Not a lot of layout is always necessary with lovespoons and most of the work is intuitive, with at least some of the planning evolving as the work proceeds. It's still a good idea to plan as much as possible and include as many guides as possible... just expect the unexpected.

With both sides of the outline cut and the profile marked out it's time to reassemble the block with clear packing tape and begin shaping the profile on the band saw. It might have been a good time to drill for all the inside cuts at this point but some of these areas are quite small and I don't trust my drill press to drill accurately to a great depth with a fine bit.

I also want to reduce the thickness of the blank in some places to make cutting easier on the scroll saw, especially if finer blades are used and possibly if a hand fret saw or even piercing saw is needed for tricky spots.

shaping the profile will remove much of the pattern but I'm expecting to do this often, as I go, any way and I can always cut pieces as templates from any extra prints of the pattern
I make along the way ... I don't find re-drawing too much a problem though and If I did, then I would find a way to avoid it.

The reassembled block can be worked on with a hand saw making intersecting straight cuts to remove large volumes of timber in shaping the rough form of the spoon's profile but things are much quicker using the band saw. The band saw makes it easier, not just because it can make curving cuts, but also because it can produce fairly accurate vertical cuts quickly, where you can observe them approaching your marked lines, to be stopped just where you want.

I used a 3 tpi half inch blade, the aggressive cut of which, enabled a nibbling away, by straight cuts, of many of the tightly curved areas. I had a 3mm blade that might have navigated many of the curves but I wasn't sure of cutting four inches of cherry, without a breakage, if a tight spot eventuated.

By taking it slowly and carefully with the large blade, easing the passage of the blade with multiple straight cuts and sometimes cutting a half inch space to allow entry for the blade to make rip cuts, parallel to the long edge, I was able to effectively, if not prettily, shape the profile.

Shaping the Profile on the Band Saw

Shaping the Profile on the Band Saw

The blank roughly shaped

The next step will be back to the scroll saw after some pattern cutting and pasting and or re-drawing – plus drilling. The thinner timber to scroll of course comes with the severe under cutting of just that part of the blank, that rests on the scroll saw table. To remedy this I will have to set up a temporary false table on the scroll saw and then, there should be no problem. This could have made things a bit easier cutting out the outline... If i'd thought of it at the time.

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