Edge durability?

[Chas Fuggetta]

Howdy gang,
New guy here and I've got a question or two for ya.

Quick history:
A couple days ago I decided to start the tune up my jointer plane. I sharpened the edge...but only up to using a dull 600 grit sandpaper. I decided to check the edge by making a few passes on some pine. Well, I did NOT see 2 small staple posts still embedded in the wood and ruined the edge. (Next time I will use a magnifying glass/magnet to check for staples and such until I can get a small metal detector.)

Well, I spent almost 90 minutes regrinding the edge on the blade last night. Once again, I stopped short of polishing the edge as I wanted to check the angle and perpendicularity of the edge. Edge came out at 23 degrees which is off by 2 degrees and perp was also off but by only 1 degree.

I picked a new piece of wood to run the plane over and made a few passes. Of course I chose a piece with a small knot in it. So...once again I checked the edge with a magnifying glass and again the edge was left jagged.

So...will a knot ruin a blade edge? Was my edge not sharp enough? How far back should the chip breaker be? I had it at only about .030" but that seemed way too close so moved it back to about .050". I also tuned the chip breaker to fit flat against the blade so I know that wasn't an issue.

Are there any vids out there that can explain some of the basics of hand planing and sharpening?

any help is appreciated.

BTW, this has got to be THE BEST woodworking site I've found. The quality of work I've seen posted here is amazing and someday hope to post some pics that won't embarrass any of us. :p

Regards,
Chas

[Dewald van Lamp]

Just start reading this forum and any other woodworking related forums.

Once you've got a basic understanding of sharpening, you will appreciate this advice.

Glad to have you on the same slippery slope with all of us..!

READ! READ! READ!

:D

[Seth Dolcourt]

Chas,

My own opinion. After all is read, watched, absorbed and trialed, you'll find that the way to a sharp edge is only a matter of moments. Save the really fine honing for your smoother and block. The scrub, jointer and jack need to be functionally sharp, but not electron-splitting sharp. I'd say stop at 600 grit, and git planin'!

I'd agree with raising the blades angle. 23 degrees sounds too shallow for hard work.

I set my chip breaker approx 1/16"-1/8" behind the iron's edge. I never measure, because then I'd be wrong, in someone's book.

Cheers,

Seth

[Rob Young]

Howdy gang,
New guy here and I've got a question or two for ya.

Quick history:
A couple days ago I decided to start the tune up my jointer plane. I sharpened the edge...but only up to using a dull 600 grit sandpaper. I decided to check the edge by making a few passes on some pine. Well, I did NOT see 2 small staple posts still embedded in the wood and ruined the edge. (Next time I will use a magnifying glass/magnet to check for staples and such until I can get a small metal detector.)

Well, I spent almost 90 minutes regrinding the edge on the blade last night. Once again, I stopped short of polishing the edge as I wanted to check the angle and perpendicularity of the edge. Edge came out at 23 degrees which is off by 2 degrees and perp was also off but by only 1 degree.

I picked a new piece of wood to run the plane over and made a few passes. Of course I chose a piece with a small knot in it. So...once again I checked the edge with a magnifying glass and again the edge was left jagged.

So...will a knot ruin a blade edge? Was my edge not sharp enough? How far back should the chip breaker be? I had it at only about .030" but that seemed way too close so moved it back to about .050". I also tuned the chip breaker to fit flat against the blade so I know that wasn't an issue.

Are there any vids out there that can explain some of the basics of hand planing and sharpening?

any help is appreciated.

BTW, this has got to be THE BEST woodworking site I've found. The quality of work I've seen posted here is amazing and someday hope to post some pics that won't embarrass any of us. :p

Regards,
Chas

A knot can really bugger up an edge. You can sometimes soften them by soaking them with mineral spirits or DNA or even BLO. Otherwise if you know you are going to be hitting a knot, go at it with a skewed (possibly heavily skewed) angle to slice more than shear.

23 degrees is close enough to the 25 standard bevel. Call it good. I've taken to grinding my bevel down blades to something close to 25 (I've bought mostly "junker" planes so often times they have very abused irons) on a grinding wheel then I move to water stones and make bevel somewhere around 27 to 30 degrees just so I don't have to spend a long time at the stones. For the backs I polish about the lower 1 to 1/2" to about 800 then use the ruler trick (google is your friend) at 6000 (I haven't invested in an 8000 stone yet). So far, so good and the edge seems to hold up even on post WW-II thin Stanley blades. And I believe all my blades are O1 or at least O1-like in hardness.

You are about to find out that sharpening is a very personal thing. What works for me (a mish-mash of techniques and methods pulled from 'net sources, Charlesworth videos and experimenting for a year) may not work for you. My method may roll some eyes here on SMC but the ultimate point is that it works for me and I can take both gossamer thin and git-er-done-thick shavings.

And so to your question about sharpening and planing videos. Schwarz, Cosman, Charlesworth and Kingshot all have good videos available. You can't go wrong watching any of them, in fact try and watch more than one. www.smartflix.com (http://www.smartflix.com) will rent you some of them otherwise they are available most of the usual places and possibly through inter-library loan programs. A quick search with Amazon.com will turn up exact titles for you to locate.

On the free, internet watchable list:
Lie-Nielson has a YouTube channel with some good short videos on various sharpening and planing tid-bits. Also Ron Hock has a video on his site (and YouTube) that imparts some good information. There are a couple of nice videos made during Woodsmith Store seminars (www.woodworkingonline.com (http://www.woodworkingonline.com)). Wood Magazine has a how-to video on basic grinding and the Scary-Sharp (www.woodmagainze.com (http://www.woodmagainze.com)) and Fine Woodworking has several good videos and tutorials but I believe you need an on-line membership - free for the first 14 days - to watch.


Good luck!

[Robert Rozaieski]

Yes, knots will chip your blade, especially with a 23 degree bevel. Increase it to closer to 30 degrees and you should be fine for most woods. In a bevel down plane, using a shallow angle on the bevel doesn't gain you anything because the cutting angle is determined by the bed angle of the plane. Sharpen at 30 degrees and your edges will last longer and be stronger.

[Paul Atkins]

90 minutes seems like a long time to regrind. Maybe a coarser stone? A diamond plate? It seems like you should be able to go from a totally trashed blade to razor in about 15 minutes. I must be missing something here. I notice that my Hock blades chip more than bend over like the Stanley ones. Of course those are the ones I hit nails with.

[Mike Henderson]

+1 on what Robert R. said. You could go to 35 degrees and still have 10* of clearance angle.

Mike

[Jim Koepke]

Chas,

Welcome to the Creek.

I guess I'd have to get up pretty early in the morning to post anything that has not already been said.

Some of my blades have been in bad shape and have taken a lot of time to get them back in shape. Depending on what is being done, some times the small nicks stay there until the blade has been sharpened a few times after hitting a knot or metal left in the wood.

Paul,

Are your Hock blades the High Carbon or are they the A1?

jim

[Bill Houghton]

"Planecraft," available from Woodcraft and also used, about $12 last I looked. A reprint of a British book, so you have to learn another version of English; once you do that, though, it's very good for basic planing technique.

I concur with others: your sharpening angle is too acute, leaving a weak edge. That said, not all cutting irons are the same - some are not tempered well, even from good makers. You might consider a replacement iron. Lee Valley, Hock, Lie-Nielsen, lots of others make aftermarket irons. I like Lee Valley's because they come with the back flat already. As a new sharpener, you want to get right to sharpening, not setup.

Consider, by the way, whether to get a sharpening jig. I've been frightening pieces of wood off and on for more than 36 years, and recently bought a jig - and am glad I did, as it's improved my sharpening quite a bit. You can get them for as little as $11, or spend more. Mine (Veritas Mk II) cost me $63 and has been worth every penny.

Disclaimer: I haven't compared Hock, LN, LV, etc. irons - there may well be others out there just as flat as the LV irons; nor have I done an extensive study of sharpening jigs.

This all gets easier with practice, by the way.

[Chas Fuggetta]

Thanks for all the advice/info guys.

The 90 minutes I spent fixing my first incident with metal was not only getting rid of .040"-.060" nicks, but also redoing the perpindicularity of the iron. I have a wet hollow grinder, but the wheel is only 2" wide and the iron in question is 2.25" so using 150 grit paper on a flat surface took a bit of time.

I'll do more research and...practice practice practice!