Mark V saves - DeWalt planer blades
Posted: Sat Apr 12, 2008 12:54 am
Yeah! That's right! Because of the wonderful features of the Mark V and Shopsmith ingenuity, the users of the DeWalt 735 planer can now re-sharpen their old blades. Some of our forum members have DeWalt planers, with "disposable blades". Other members have other brands that have "disposable blades" The ability to re-sharpen them will save both in money and time.
In other threads, we discussed one of the ignoble features of the 735 was "you can't re-sharpen their blades. I have been thinking, Why not? When armed with the Shopsmith Planer/Jointer knife Sharpener (555471), and a Conical disk, it can be done. A new set of three blades costs about $55. Re-sharpening twice can bring this cost down to very reasonable. The SS sharpening jig costs about $50 so since it can be used to extend the blade life up to at least 3 times, it is a good buy for anyone having a 735.
I was hesitant to say anything on the Forum until It was done and these re-sharpened blades actually worked. Today, I re-sharpened used and nicked blades successfully and planed out about 40 lineal ft. of oak. The resulting surfaces were glossy smooth with absolutely no ridges from old nicks.
There are several considerations associated with sharpening these blades.
First- Care must be taken to grind off only the bare minimum amount of metal to remove chips and gain a keen edge. The blades must be installed at a fixed location in the planer. They can slide from side to side, but cannot be made to protrude outward any farther than the originals. Therefore as a new edge is ground the blade becomes narrower than the original. One would expect the resulting planing cut to be higher than the original new blades.
Second - The blades are thinner the the Shopsmith planer and jointer blades therefor the jig is not designed for those thinner blades. To use the jig, remove the spring washers beneath the clamp and lay the blade on the normal shelf as designed for SS blades. Put a 3/4" X 1/16" strip of wood on top of the blade beneath the jig clamp. Even though the blades protrude about 1/2" on either side of the jig, that does not present any problem. Just center the blade, clamp down on the wood, set up the Mark V and away you go.
Third - Tilt the Mark V table 2 degrees backward, away from the conical disk. (actually 2.5 degrees) This will replicate the same blade bevel angle as the original.
Observations - I removed small nicks from all three blades. Although I class these as small, they were deep enough to cause visible ridges in planed wood. Although I was concerned the re-sharpened blades would be too much thinner than the originals, this did not happen. I didn't have a micrometer, but the re-sharpened looked to be the same width as the new blades.
After planing the boards to 1/4" by use of the machine's stop, my caliper showed them to be 1/4" on the money. Cerebrally, I know this can't be factual, but my caliper doesn't lie. Therefor I come to the conclusion that the blades can be resharpened multiple times, maybe even 3 or 4 times. Anyway, the effect will be to make wider boards. It's easy to make thinner ones!
P.S. Looks like I had 2 1/2 degrees rather than 2!
In other threads, we discussed one of the ignoble features of the 735 was "you can't re-sharpen their blades. I have been thinking, Why not? When armed with the Shopsmith Planer/Jointer knife Sharpener (555471), and a Conical disk, it can be done. A new set of three blades costs about $55. Re-sharpening twice can bring this cost down to very reasonable. The SS sharpening jig costs about $50 so since it can be used to extend the blade life up to at least 3 times, it is a good buy for anyone having a 735.
I was hesitant to say anything on the Forum until It was done and these re-sharpened blades actually worked. Today, I re-sharpened used and nicked blades successfully and planed out about 40 lineal ft. of oak. The resulting surfaces were glossy smooth with absolutely no ridges from old nicks.
There are several considerations associated with sharpening these blades.
First- Care must be taken to grind off only the bare minimum amount of metal to remove chips and gain a keen edge. The blades must be installed at a fixed location in the planer. They can slide from side to side, but cannot be made to protrude outward any farther than the originals. Therefore as a new edge is ground the blade becomes narrower than the original. One would expect the resulting planing cut to be higher than the original new blades.
Second - The blades are thinner the the Shopsmith planer and jointer blades therefor the jig is not designed for those thinner blades. To use the jig, remove the spring washers beneath the clamp and lay the blade on the normal shelf as designed for SS blades. Put a 3/4" X 1/16" strip of wood on top of the blade beneath the jig clamp. Even though the blades protrude about 1/2" on either side of the jig, that does not present any problem. Just center the blade, clamp down on the wood, set up the Mark V and away you go.
Third - Tilt the Mark V table 2 degrees backward, away from the conical disk. (actually 2.5 degrees) This will replicate the same blade bevel angle as the original.
Observations - I removed small nicks from all three blades. Although I class these as small, they were deep enough to cause visible ridges in planed wood. Although I was concerned the re-sharpened blades would be too much thinner than the originals, this did not happen. I didn't have a micrometer, but the re-sharpened looked to be the same width as the new blades.
After planing the boards to 1/4" by use of the machine's stop, my caliper showed them to be 1/4" on the money. Cerebrally, I know this can't be factual, but my caliper doesn't lie. Therefor I come to the conclusion that the blades can be resharpened multiple times, maybe even 3 or 4 times. Anyway, the effect will be to make wider boards. It's easy to make thinner ones!
P.S. Looks like I had 2 1/2 degrees rather than 2!
