replying to toolmiser, StevenWoodward wrote: am 14 years late in joining this discussion, but the RC-33 (22-650) machine mentioned above lasts forever so there may still be some interest.
I purchased mine in 1984 and have had no trouble with it. Sharpening the 13 inch knives has been the biggest challenge. I used to get them done by a good sharpening shop, and they came back not only sharp but straight. Straight is important because you want all three blades to be cutting into the wood evenly. That sharpening shop went out of business in the 2009 recession and I could not find another local shop that would sharpen the knives straight. Straight means no light when blade is held against a steel ruler. I tried to sharpen myself with a Makita 9820-2 surface grinder. I could get them sharp but could not get the edge dead straight.
Finally decided to replace the cutter head with a Byrd Shelix helical segmented head. Glad I did: no more sharpening, no more knife setting, and much less tear-out when planing difficult wood. When the carbide cutters get dull, just rotate them 90 degrees to expose a new sharp edge. When all 4 edges have been used, then replace that cutter. Only the cutters which are chipped or dull need to be rotated, so no waste. It is a great system and cheaper than paying to have straight blades sharpened. As there were no upgrade instructions available for the RC-33, I created a YouTube video which also shows lubrication and adjustments of the RC-33.
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watching the video, you may find it easier to work from a written upgrade instructions, which are available in the following folder, along with other documents for the RC-33.
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