Stanley No71

[Dave65]

I've recently bought an old Stanley No71 router plane, which has cleaned up ok, I now need to sharpen it!! Half inch cutter first, I've flattened the bottom and got an nice even, square primary bevel, the question is where do I hone the secondary bevel, if at all ?? Paul Seller has a video showing him putting a secondary bevel on the bottom of the cutter, parallel with the base of the plane. Rob Cosman puts a secondary bevel on the top of his cutter, like the iron in a block plane, or do I just hone the primary bevel until a burr is raised and then strop? Any advise on which method gives the best results.

 

[Argus]

To my way of thinking, there are two answers to this. The goal is to have a mounted blade-edge that is exactly co-planar with the sole of the plane and in so doing will give a flat, even cut.

Typically, the cutter is foot-shaped and tilted very slightly so that the cutting edge is presented at a slight angle to the work. Normally the foot of the blade is flatted and polished as you would with the back of a chisel - without a back -bevel. The upper side, the top-bevel is then honed to a cutting edge. At this point you have a 'chisel on a stick'.... as it were, titled forward at about 2 - 4 degrees.

If the mounting pillar on the router and the blade-shank are perfectly aligned in the vertical plane this is as far as you need to go. Sharpen and hone that top bevel and plane away.

However, in reality, very few router planes and their interchangeable blades are like this, so there may be an alignment issue at the meeting point of the cutting edge and the work, which if it isn't rectified, will give an uneven and streaky finish because one edge will be slightly higher than the other. At this point you may adjust it by honing away a section of the bevel so that it is all level and co-planar with the sole, or introduce a slightly-tilted back bevel to correct and achieve the same result.
Continuing the back-bevel issue, to my way of thinking, is that of the angle. If you have one it must be less than the inclination of the blade's foot otherwise it will not cut and maintaine that way evermore. It's further complication in life that we can do without.

I have the similar Record version of that Stanley router and sure enough, even with a Lie-Nielsen blade, as well-made as it is, there's a slight misalignment.

My solution was to correct it solely on the upper bevel because in future sharpening I only have one thing to worry about - the top bevel - not two bevels plus the angle of the back bevel..

If it's a newly acquired router, it may be worth a little basic fettling as well..... some routers were better made than others during the decades that they were in production. It may help to look at the mating surfaces where the blade's back and the inside parts of the mounting pillar meet; make sure that they are good, clear and flat, without bumps in the plating that will prevent the blade sitting firmly in its working position. A minute amount of interference in this area can shove a good blade out of alignment and make it prone to loosening in action.

Hope that this helps...

 

[pe2dave]

My routine:
Once square, leave the sole alone.
On a diamond stone, invert the cutter, gentle pressure centred on the cutter, zig zag forward and back (across the stone) whilst slowly walking down the stone. Once near the edge, I lift fractionally, and give it a very few rubs to form a tiny bevel. Works for me - a lovely useful tool.

 

[raffo]

To my way of thinking, there are two answers to this. The goal is to have a mounted blade-edge that is exactly co-planar with the sole of the plane and in so doing will give a flat, even cut.

Second that observation. The Paul Sellers video shows you how to check for that and how to correct it, doesn't he work the bevel to achieve coplanarness? I wouldn't add a back bevel.

 

[Dave65]

To my way of thinking, there are two answers to this. The goal is to have a mounted blade-edge that is exactly co-planar with the sole of the plane and in so doing will give a flat, even cut.

Typically, the cutter is foot-shaped and tilted very slightly so that the cutting edge is presented at a slight angle to the work. Normally the foot of the blade is flatted and polished as you would with the back of a chisel - without a back -bevel. The upper side, the top-bevel is then honed to a cutting edge. At this point you have a 'chisel on a stick'.... as it were, titled forward at about 2 - 4 degrees.

If the mounting pillar on the router and the blade-shank are perfectly aligned in the vertical plane this is as far as you need to go. Sharpen and hone that top bevel and plane away.

However, in reality, very few router planes and their interchangeable blades are like this, so there may be an alignment issue at the meeting point of the cutting edge and the work, which if it isn't rectified, will give an uneven and streaky finish because one edge will be slightly higher than the other. At this point you may adjust it by honing away a section of the bevel so that it is all level and co-planar with the sole, or introduce a slightly-tilted back bevel to correct and achieve the same result.
Continuing the back-bevel issue, to my way of thinking, is that of the angle. If you have one it must be less than the inclination of the blade's foot otherwise it will not cut and maintaine that way evermore. It's further complication in life that we can do without.

I have the similar Record version of that Stanley router and sure enough, even with a Lie-Nielsen blade, as well-made as it is, there's a slight misalignment.

My solution was to correct it solely on the upper bevel because in future sharpening I only have one thing to worry about - the top bevel - not two bevels plus the angle of the back bevel..

If it's a newly acquired router, it may be worth a little basic fettling as well..... some routers were better made than others during the decades that they were in production. It may help to look at the mating surfaces where the blade's back and the inside parts of the mounting pillar meet; make sure that they are good, clear and flat, without bumps in the plating that will prevent the blade sitting firmly in its working position. A minute amount of interference in this area can shove a good blade out of alignment and make it prone to loosening in action.

Hope that this helps...

Thanks Argus, some useful pointers there. I have mounted the blade back in the plane and checked on a piece of glass and everything looks fine, the edge of the blade is co-planar with the sole of the plane . I'm going to check the fit of the blade in the mounting pillar now you have mentioned it, just to be sure.

 

[Dave65]

Second that observation. The Paul Sellers video shows you how to check for that and how to correct it, doesn't he work the bevel to achieve coplanarness? I wouldn't add a back bevel.

Yes, he covers the sole of the plane with tape then, with a tiny amount of set on the blade, makes a couple of passes on the diamond plate to give a small bevel, then adjusts the primary bevel to suit.