cambering plane blades with the SE-77

[Ken S]

Ever since I started using the Tormek I have wanted a controlled way to camber plane blades. (Cambering is making the edge of the plane blade slightly convex, thus eliminating "plane tracks", the sharp corners of the edge cutting into the wood.)

The new SE-77 can be adjusted for differing amounts of camber. The left and right side knobs can be backed off three turns, or three millimeters each. There is an easy to see witness mark on the side of the jig facing the operator. When the jig is adjusted to match the witness mark and the two screws are tight, the blade should be square. minor adjustments may be made to compensate for the tool.

I follow Chris Schwarz' method of coarse, medium and fine. Coarse would be for a jack or fore plane. This is the first plane used to remove a lot of wood. Having the two screws moved out two to three turns gives a good camber for a jack plane, around 1/16 to 3/32". When the two screws are each loosened only one turn or so, a good medium is obtained, approximately .006", which is right for the jointer plane. Having the screws only backed out a half turn or less gives a good fine camber for a smooth plane, approximately .002 or finer.

The process will vary somewhat with the width of the plane blade. I was using a two inch (50mm) blade, the standard width for number four smooth planes and number five jack planes. The user can customize his settings.

I recommend a light truing cut for the grindstone before sharpening blades with camber. A bit of practice helps, too.

For woodworkers using hand planes, in my opinion, the camber feature of the SE-77 represents a substantial improvementBeing able to adjust the projection angle of a chisel slightly for square without loosening the chisel is a nice to have feature. For hand planes, I consider the camber adjustment a feature worth purchasing a new jig to get.

Ken

[Dakotapix]

I see that the US release of the SE-77 jig is about mid-June and will cost $66. I probably will have to get this. I recently tried to camber a blade on an old 16-inch woodie manually by rotating the blade on the platform/tool rest. It came out okay but I'd rather have more control over the camber radius.

[Ken S]

Dakotapix,

I think this new jig is a good investment for serious handtool workers. In my case, I was given a test and review sample. However, if I had to pay for it, I would still feel the same way. I think it finally brings the same level of control to square edge tools that turners have with the new gouge jig.

Ken

[Jan]

Ken, I have allowed me to add metric conversion to your figures in inches. 

Jan

Having the two screws moved out two to three turns gives a good camber for a jack plane, around 1/16 to 3/32" (1.59 to 2.38 mm). When the two screws are each loosened only one turn or so, a good medium is obtained, approximately .006" (0.15 mm), which is right for the jointer plane. Having the screws only backed out a half turn or less gives a good fine camber for a smooth plane, approximately .002" (0.05 mm) or finer.

[Ken S]

Thanks, Jan.

Living in the inch hinterlands, I sometimes neglect to add the proper metric measurements when pressed for time. I appreciate your help.

Ken

[Ken S]

More camber controls:

In the pre SE-77 era, the standard practice was to project the plane blade further to allow it to flex. The flex was what allowed adding camber. This worked adequately with thinner blades such as older Stanley and Record blades. Premium blades are now thicker. I do not own one, but suspect they do not flex well. (Verification from other members is most welcome.)

With the SE-77, we can rotate the blade;we no longer need flex. Therefore, we can experiment with different, specifically shorter, projection lengths. When I first read the instruction sheet for the SE-77, I was disappointed that it did not include tables for camber settings. I now realize that there are enough individual user variables that it is more practical for each user to make up his own tables. This is neither complicated nor involved. Most users will probably have three setups: the smoother, the jack and the jointer.

I simplify setting the distance from the universal support to the grinding wheel by using either the A or B hole of the TTS-100. These are not optimal, just consistent. Either the black marker or the anglemaster work well with plane blades. My preference is to make marks on a piece of white label tape placed in the 55mm slot of the TTS-100. I use the anglemaster to set the mark initially.

With the distance and projection length set, the only variable is the "jig setting", borrowing the term and technique from the Tormek gouge jig. These ideas are not original, just adapted from the Tormek "Touch N Turn" technique for turning gouges.

During my next sharpening session, I will try varying the projection length and report the results.

Ken

[Ken S]

Update:

I did some more camber sharpening today. I used two Stanley two inch wide plane blades (50mm). This width blade fits both the number four and five planes, the "garden variety" smooth and jack (fore) planes. I used the two settings of the TTS-100 to standardize the distance between the universal support and the grinding wheel. I wanted to see how these two predetermined distances compared when using maximum camber. The further distance, "A" allowed a miniscule amount more camber than the B setting. Maximim camber was approximately 1/16" or 1.5mm. The A setting allowed a smoother movement during grinding.

There is nothing inherently correct or incorrect about either of the two TTS-100 settings. I use them for planes and chisels because they are consistently replicable and I happen to have a TTS-100. I use the longer distance for plane blades and the shorter setting for chisels. I set the projection distances by using predetermined slot distances (black marker lines on blank label tape placed in one of the three slots of the TTS-100. This is essentially the standard Tormek set up method for turning gouges.

For anyone using the anglemaster or black marker, the procedure is easier if the blade projection length is set first and then fine tuned with the microadjust with the universal support.

Incidentally, I tried placing a standard spokeshave blade in the SE-77. The SE-77 is capable of holding the spokeshave blade. I would prefer having a longer contact distance between the registration fence of the jig and the side of the spokeshave, however, this can be easily overcome by working carefully. Careful technique carries the day.

More updates as they become available.

Ken

[Dakotapix]

Has Tormek released a video on the SE-77 jig yet. It would be good to see this in action.