SHARPENING PLANNER BLADES

[dusty]

What is the desired bevel angle? I don't find that question answered directly anywhere in the technical data.

If you use the conical disk and the Shopsmith Sharpening Jig with the table set at 90° to the blade, the resulting bevel will be very near 45°.

The 'measured' bevel angle on a new planer blade is 40°.

I now suspect that it was not a new set of blades I was using when I made these measurements. Measuring two other sets, the results are closer to 45°.

[JPG]

Ref: planer manual.

planer grind angle.jpg (129.99 KiB) Viewed 1948 times

[dusty]

I have never tilted the table with this, and have not seen where that has been even recommended.

Here's what Shopsmith says about it with the Conical Sanding Disk: "Special nylon glides on the back and bottom edges ensure the guide's smooth travel over your Mark 7 or Mark V tabletop and against your rip fence as it holds your Knives at the precise, correct angle while you sharpen them."

The point is the Disk is made at a specific angle, and the tool is designed to provide the correct angle.

Do you have the Shopsmith instructions on use of it?

Don't get too aggressive, just very light passes and you will likely love the results.

Look at where the table is in relation to the tool though in the picture.

Everett
Sharpener.png

I have no argument with what you have said but there is a need for some clarification.

New planer/jointer blades come with a 45° bevel and a 2° taper.

If you install those new blades in the Shopsmith Sharpening Jig and then sharpen them using the Conical Disk without tilting the Main Table the result will be planer or jointer blades with a new bevel of 43°. Shopsmith, in the manual does indirectly state that this will work just fine especially if working with hard woods.

Remember: The bevel angle that results from either no tilt or tilt toward the conical disk is a negative change. If the desired bevel is a positive change (46-48 degrees), the table must be tilted the other direction.

Bottom line: If you want to retain the original 45° bevel, you must alter table tilt 2 degrees.

Shopsmith, in the reference quoted earlier in this thread by JPG, states that it may appropriate to alter the bevel +- 3° (42° to 48°) based on the hardness of the wood being worked. That can best be achieved by "tilting the table".

Additional Comment: Shopsmith incorrectly (in my opinion) states that the table is not to be tilted when using the conical disk. Their comments on this are somewhat vague and possibly misleading. They do clearly state that if you are face sanding a surface that needs to be 90°, you tilt the table and use a square to achieve the desired angle.

The NOTE that states the work table Must Not Be Tilted 4 degrees as described in the Conical Disk Owner's Manual is incomplete and misleading. Following these instructions to the letter alters the bevel and this is OKAY but only if a 43° bevel is your objective. The confusion is caused in part by the fact that these instructions are in a document that deals with the conical disk in conjunction with the sharpening jig. Furthermore, they completely ignore the fact that it may be desired to alter the bevel angle (which necessitates table tilt adjustments).

Shopsmith never comes right out and says this in clear text but it is implied in those instructions.

There are additional instructions in the Shopsmith manuals on these topics. All of them are pertinent in some way to this discussion. They must be read together to get a clear understanding of the Sharpener and the Conical Disk.

Sorry about the duplicity but I believe these need to be read together.