Scary Sharp Sharpening Method

[rick7938]

I have been reading a lot about this Scary Sharp sharpening method on various internet sites. I have tried it, and it seems to work great. However, I have one question that may be totally irrelevant, but:

When you flatten the back of the plane/chisel blade, is it better to move the blade against the sandpaper back and forth along the long axis of the blade, or side-to-side along the short axis of the blade, or should I alter between grits to ensure that the scratch marks from the coarser previous grit are gone?

Thanks for any input and opinion.

 

[nelsone]

Rick, I don't know if I can be much help since my sharpening skills are no where near good enough. When you are working a new tool, flatening the back is the first step, working through the grits. After that work the edge through the grits and then a light swipt on the back to remove the burr. I have always gone side to side on the back, so I'll be interested in hearing from some of our more skilled members!

 

[walnutjerry]

I have been reading a lot about this Scary Sharp sharpening method on various internet sites. I have tried it, and it seems to work great. However, I have one question that may be totally irrelevant, but:

When you flatten the back of the plane/chisel blade, is it better to move the blade against the sandpaper back and forth along the long axis of the blade, or side-to-side along the short axis of the blade, or should I alter between grits to ensure that the scratch marks from the coarser previous grit are gone?

Thanks for any input and opinion.

Rick----------Personally, I do not think it matters. IMHO, what matters is that you get the back flat all the way across both directions. Especially taking note to get it flat all the way to the point of the bevel. Once you have accomplished this you should never have to lap the back of the tool again. All that is left is to keep the face of the bevel honed. I am not an expert on the subject----just passing on what I have been told.

Jerry

 

[gator]

I use sort of a circular or ovalar (new word?) action. I hold the iron sideways but work it in a circular fashion instead of a straight back and forth action.

George

 

[Ozzie-x]

If you hone the back down to 2000, 4000, 8000?, it probably doesn't really matter. In the original "Scary Sharp" article, Ron Hock illustrated the back honing with the blade hanging off the side of the stone or paper at an angle and reversing the angle with each grit step. The Lie-Nielsen guy does the back in a circular motion on his waterstones.

Generally, I push the blade straight against the paper or stone so the the blade material is removed away from the edge, particularly in the finer grits. It always seems like this method makes for a sharper edge and minimizes burring on the bevel side of the edge. Of course this is a pain if you have a honing guide on the blade, but seems to work better. The back should be honed every time you touch-up or resharpen since the back forms the other half of your cutting edge.

 

[sawman]

Rick,
I agree with everbody on the plane iron, it makes no difference. When you get to the .05 paper (I think that is the highest) which is 20,000 grit it makes no difference.
The chisel I usually start with a 220 wet/dry paper to flatten the back in a foward and back motion. The cost of the 400 grit paper is high so using a 220 will save you some money.
I also keep some of the used paper to elevate the hone guide to the grit paper being used. That slight difference in height makes you cut more than needed, in my opinion.
I also cut the entire face and only use the micro bevel if I am in a hurry.
I just feel better when the entire face is honed.

Later,
sawman

 

[Gofor]

No expert here, and until I can get a good bench built that doesn't move when I plane something, I don't think I can give a good comparison on each method's results as to sharpness and durability. That said, I have seen other's remarks that make sense. I am paraphrasing these so they are not direct quotes:
1. "Moving the blade sideways shears off the burr rather than breaking it off, leaving a smoother edge (microscopically)"
2. "Once the back is flattened and polished, it should not need reflattening, only removing the burr. Sliding a machinist scale under the back end of the blade (ruler method) produces a reverse microbevel of only about 1/2 degrees to remove the burr without affecting the flatness.

I haven't tried either of the above yet, but will next time I break out the "armstrong powered" planes. Until I get some top quality blades (Santa, are you hearin' this?) I think its a moot point for me. I have been using a figure 8 method 'til now as that was how I was taught to lap lifters for diesel engines to get them flat (years ago), and I concentrate on keeping the blade flat on the paper. I make sure I wipe off the blade before moving to the next finer grit to prevent transferring a heavier grit. I do usually end up finishing with my hard arkansas stone, tho, because it seems to give me a sharper edge than 2000g paper (the finest I have). Haven't broke the .001" shaving mark, yet but am really close (.0012) (I used to be a machinist many years ago and kept some of my .0001 tolerance mics)

Still learnin'
Go

 

[Ozzie-x]

I looked in the link library and don't think we have Ron Hock's website in there? I submitted the link for consideration to be added to the library, but here's the link: Hock Tools: Blades for Planes and Hand Woodworking Tools There's a lot of good info on the site about blades, metallurgy, sharpening theory, and the "Scary Sharp" that I think Ron originally published. He has a new video on there that's pretty interesting.

 

[McRabbet]

Link has been added and validated.

Rob

 

[junquecol]

For final polish on both front and back, I use some Tormek Paste on a block of MDF. Adding a drop of light oil to MDF, prior to paste, seems to help. Real easy to see my face on backs then. I don't use a guide, but work free hand. Move chisel side to side. Looks kinda wierd, but works for me. Hair jumps off my arm to get out of the way of chisel.

 

[antioch8]

I have tried flattening the back all three ways mentioned and have found the side to side method and the circular method works best for me with nearly identical results. It may be just me but when I move the iron along its long axis it leaves less than desirable results. I personally feel moving along the long axis can kind of push the sandpaper up in front of the blade resulting in a slight rounding of the cutting edge that is hard to hone away. I use wet/dry sandpaper held to a piece of 1/2" plate glass with either spray adhesive or if I am in a hurry the surface tension created by water on the glass. Hope this helps..........

 

[cpowell]

I flattened the back of my Marples chisel set -1/4, 1/2, 3/4 and 1 inch tonight for the first time, then sharpened them using scary sharp and a Veritas MkII honing guide I bought today at Woodcraft. LOML didn't want me to use it until after Christmas. She wanted to wrap it and put it under the tree. DL was working and suggested she simply wrap the box and let me use the guide (Thanks, DL).

I've had the chisels over a year. I didn't realize when I first bought them that anything had to be done. I figured they were new and sharp. :eusa_doh:

It took several hours to finish but the results are worth it. The 1 inch chisel was actually skewed from the factory. One side was about 3/32nd longer than the other. I worked through three sheets of 60 grit to make a primary bevel and square up the ends. My fingers are worn out!! :lol: :lol:

I don't know if all of you can still remember the first time you used a chisel that was as sharp as a razor. Man, what a feeling to be able to shave end grain effortlessly. :-D They're gonna be kept sharp from now on.

Chuck

 

[Gofor]

Just did a few plane blades as well a sharpened a brand new one. I found that for me:

For the square blades: The circular combined with the straight forward method worked best for the intial sharpening. I found it hard not to "rock" the blade. (My sharpening "fixture" is a carriage bolt with washers and wing nuts) At the 2000 grit level, tho, it did seem to produce a slightly finer, more polished edge.

For the cambered blades, side to side (actually swinging it in an long arc) through all grits produced an even radius and resulted in a very sharp blade. (This was for about a 0.003 camber)

At present, the finest I have run them on is 2000 grit wet/dry paper and can now get a 0.001 shaving on soft maple. Hopefully this week I will have time to run them across my hard arkansas stone, which in the past has produced the keenest edge.

Used the "ruler" method on two of the older blades that had some minor pitting on the flat side and it seemed to worked well.

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