Card Scraper Sharpening..

It’s a long time since I last sharpened a card scraper and I don’t remember doing it right, so I watched a couple of DVDs about how to go about it. One was by Christopher Schwarz and the other by Rob Cosman.

Both had good tips.

I have two card scrapers and ended up sharpening both by slightly different methods, just to experiment.

First, I had to clean each scraper. They both had various marks on them and also had burrs on their edges from previous attempts.

I “stuck” a sheet of 400 g wet and dry to my reference block with water…

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Cleaning Method One. I put double sided tape on one scraper then stuck it to a block of wood…

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…then rubbed it on the paper…

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That worked ok, but it was a pain to peel it off, peel off the tape and do it all again on the other face. So…

Cleaning Method Two. I tried using some magnetic clamps on the other scraper…

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That worked a lot better. I could also flex the scraper, which meant I could clean near the edges which is the critical part. So Method Two it’ll be then.

Next, the edges. Method One was to mark on one edge with a marker pen..

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…then file it flat and square with a smooth file in a jig..

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That gets it square and flat, but leaves file marks. So then I had to use my sharpening stones to polish the edge. First, the 1200 g waterstone. Using the block to keep it square, I moved it back and forth until the file marks were gone…

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…then finished up on the 6000 g stone. That got the edges polished, but wore grooves in the stones, which had to be dressed out. That’s a black mark against that method, so…

Method Two. Instead of using the file and the stones, I processed the other scraper’s edges on Wet and Dry on the reference plate. In succession, I used 400, 1200 and 2500 grit paper, using the block to keep square. That was quick, easy and got, I think, a better polish on the edges. No dressing of stones after. Method Two, 2, Method One, nil.

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This is the edge…

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Next, I used the David Charlesworth Ruler Trick (DCRT) on the face edges…

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That was on the 6000g stone. I also tried the 2500g paper. No discernable difference in polish. Probably use the paper, as Method Two will be set up at that point.

I used my Hock Burnisher to consolidate the face side edges…

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…by moving it back and forth with reasonable pressure. Next I turned the burr…

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…tilting over by about 10 degrees. These are some shavings…

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I didn’t feel that I got excellent results, though. There seemed to be a lot of dust as well as shavings. That usually means the burr isn’t quite there, or perhaps it’s the way I hold it. On the plus side, both scrapers certainly cleaned up the Maple Feet.

I’ll experiment further in the future.

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Hinge was missing her Bracket…

…Be wise, my son, and make my heart rejoice, So that I can make a reply to him who taunts me…

That was a surprise; that self retracting castor. Logical when you analyse it, though. This is the problem…

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In the left picture, the axis of the wheel A is far from the hinge at B and the direction of rotation – red arrow – all helps to keep the castor flat under the Foot. In the right picture, the axis of the wheel A is so close to the hinge B that the direction of rotation helps to rotate the entire assembly anti clockwise, around the hinge axis.

The solution is a bracket to hold it in place. Here’s one I’ve already screwed to a support block ready to drill…

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Why drill a hole? The existing hole on one leaf – where the screw is – finds itself too far out as that leaf is too long to fit on the castor plate, so needs cutting. The above picture shows a mark made closer to the angle, where the new hole will go. The HCPD was set up again…

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…the hole drilled and the outer portion of the leaf cut off…

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I made four…

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A corresponding hole was drilled in each castor plate…

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The angle plate and the castor are joined with a 4mm bolt and nut. This picture shows why the angle plate had to be altered on one leaf…

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This is the castor reassembled on to the hinge and Foot. Under the head of the 4mm bolt, I drilled a recess, so the castor plate would still be flush. A pilot hole was drilled in the Foot and a 5mm by 25mm screw fitted…

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I cut off the little 4mm bolt close to the nut. The Base was upturned and the whole lot tested…

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It all worked just fine. Here’s a finished picture…

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Screwing the castors on whilst in the castoring position seems labour intensive, but once the lathe is assembled, I won’t be moving it much. I timed it; it took 1 minute per screw. Not too long every so often. And it’s a simple solution.

The final operation is to finish and protect.