Flattening blades
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14 September 2015 at 12:35 am #130387
Sorry if this has been asked but I need some help flattening. I know Paul did a vid and used sandpaper up to what 2500 grit or so? That’s all well and good but in everyday sharpening he seems to remove the burr on his super fine eze lap and the do his stropping. Doesn’t the act of removing the burr on the diamond stone introduce scratches?
Also, I just got my eze laps and as many have reported the stones are quite rough. After stropping I did not have a polished bevel. This was on leather with green compound. Is it because my super fine is too rough to make the transition straight to the strop?
14 September 2015 at 4:14 am #130396Mike, I don’t know if I’ve been lucky but I’ve never had a problem flattening a chisel or iron down to my extra fine diamond stone, following with a strop on the green honing compound. I get perfectly mirror finishes on the backs that way. You can go finer than that on a stone, but the compound is something like 15,000, so it always seemed like a waste to go past 1200. So removing the burr on 1200 isn’t really a concern as far as I see. Take a few swipes on the strop on the back every once in awhile to touch it up.
I think we worry about these things too much and over-complicate things. If the chisel or iron is sharp and can take hair off your arm, it will cut wood just fine.
I couldn’t see the second part of your question, with the new strange problem on the forums of not being able to see the text in the first post.
14 September 2015 at 4:30 am #130398Thanks for the reply Derek. I know your right about over complicating things. I can’t help but feel that my blades aren’t as sharp as they could be. I was planing some hard maple yesterday and I just feel like I am having to push as hard as I would a car or something. My bench was trying to move even. Then I read about guys effortlessly paring end grain with chisels and I see Paul working white oak… I’m missing something and that something seems to be sharpness.
14 September 2015 at 11:31 am #130424Planing does involve some effort unless you’re taking whisper-thin shavings. Some things to try to make life easier, in rough order:
Take a thinner shaving
Lubricate sole (using candle wax or the raggy oil can, whichever you have to hand)
Ensure no shavings are jammed in the mouth
Check sharpness
Retract cap iron, try 1-1.5mm
Camber blade slightly – flat edges offer more resistance for the same shaving thickness (but take narrower shavings and leave a rippled surface, to a greater or lesser degree depending on the camber)Try it on a different piece of wood, some bits are just really stubborn.
Matt
Pushing so hard that you’re fighting the bench sounds too hard. Did you try planing from the other direction? If you feel like changing the depth of cut gives you only two options, either sliding with no shaving or digging in and having to push really hard, then it sounds like sharpness. I’ve had trouble at times with not getting the burr off when sharpening. The edge looks sharp and it won’t feel like a burr, but if you try to cut with it, you might get a good cut or two and then it deteriorates quickly. If you feel for a burr after a few cuts, you feel one is back.
Paul showed me a trick of getting a hard bit of scrap, like oak or maple, and then driving the chisel into the face, cross grain as if mortising, with a couple sound blows after you’ve just finished sharpening to test whether you’ve really gotten the burr off. Feel your edge for whether a burr has come back after whacking into the hard oak. If so, go back to your superfine and repeat that part of the sharpening. You may need two or several passes on the superfine, the final one(s) very light. I’m getting better at not making this super heavy burr, but it still comes up now and again. One place this can really show up is paring shoulders in oak. Sharpen, take a couple pares, all is good, then not so good, and you find a burr is back.
Let us know how it goes. If it isn’t this, then I’ll bet it’s some other sharpening issue, or you’re just too heavy and against the grain.
- This reply was modified 8 years, 7 months ago by Ed.
14 September 2015 at 6:13 pm #130436Ed I Think you hit the nail on the head. I always feel like there is a burr left after sharpening but I just can’t seem to remove it. Sometimes I think the burr is just my imagination but I’m almost certain I feel just a slight burr.
Try working it back and forth on the superfine. Paul gets his off on the strop, but mine are sometimes too big and don’t come off that way. I’m guessing I spend too much time on some of the stones and make too big a burr. So, try working the bevel on the superfine, do the “quick pull” thing, which will push the burr back to the bevel side, then go back to honing the bevel, but lightly. Repeat. When you can’t feel any sense of a burr, whack a piece of oak and see if it comes back. If so, repeat.
By the way, if you have any question about being sharp, it’s not crazy to get a cheap Eclipse honing guide. It is slower and more tedious, but more definite to give an edge. You can then work your freehand sharpening until you get the same result. Of course, if you get and leave a burr with the eclipse, you won’t get to where you want to be either… 🙂
Here’s a final cheat. Before I switched to Paul’s method, I used waterstones. So, I already owned a really fine waterstone. It’s much finer than the superfine stone. If you have one, you can grind on the course, then *work* the back on the superduper fine stone with a dozen strokes. This will really push the bur back. Now hone on the fine, followed by working the back, then again on the superfine stone. It doesn’t matter that it’s a waterstone. Oilstone is fine, too. Or, if you’re happy with reducing the polish on the back of your blade to that from your superfine stone, you can work on it. Probably good enough. I’m just saying to work a dozen strokes rather than the quick pull. For a heavy burr, I sometimes don’t get it folded back with that method. Again, this is all debugging….once you get it, work back to the simple method Paul uses to keep things simple. Don’t go buy a superduper fine stone, though. I’m not suggesting that.
14 September 2015 at 10:59 pm #130442Really helpful suggestions. The weather is really nice today and I think I’ll give her a shot! I’ll report back to you soon.
15 September 2015 at 3:47 am #130452So I had a go at it. I’m making progress. Stropping definitely seemed to make sure I got rid of that burr. Would it benefit me to take the backs up to a really high grit on sandpaper and only remove the burr on my strop? Would the edge be better?
I hope someone else chimes in on this. The “one quick pull” trick on the superfine I think is intended to pull the burr over to the bevel. Since the burr is holding the blade up off the stone, you don’t scratch the polished back enough to matter. You then work the burr off when stropping the bevel side. I’ve never found that stropping the back side did much. The mechanics just don’t work because the edges on the back side dig in and the handle is in the way, but you should experiment. I guess I get enough on the back side to fold the burr back over if it is still there, so you could go back to the bevel again.
In short, if you mean going directly from the superfine with the grinding and honing burr still on to the strop, I’m not sure the strop will get it off, but I’m only guessing.
Did you try whacking a piece of oak or maple?
15 September 2015 at 2:14 pm #130508Ed,
Ok I see your theory regarding the quick pull to flip the burr. I did try whacking some maple and I did not feel a burr reappear on the back side. I assume I successfully removed the burr. I did notice the plane was significantly easier to push than before. This one piece of maple has a lot more reversing grain than I would normally like but I’m cheap and refuse to waste it.Thanks for all of your help thus far!
15 September 2015 at 2:34 pm #130509Some very good and helpful answers here. As far as stropping the back goes, you can also have a flat piece of wood, such as a piece of ply, with some buffing compound on it. That is what we tend to use as the final process of flattening the backs anyway, as it prevents any rounding of the edges of the back flat face. We often use the other side of the strop which has no leather on it, so you can just flip the stop to use it.
As far as a few strokes on the strop goes, we usually kind of angle the chisel to get at the strop. Have a look here:
That whole video is worth watching from time to time, as I know I tend to notice different things at different stages of my learning.
The other thing you can do to remove a stubborn burr, if it will not come off when stropping, is running the tip of the chisel through a corner of a piece of wood or the strop, like a swiping motion. This can help to dislodge it.
Hope that helps,
Phil15 September 2015 at 2:38 pm #130510Just realised you were talking about a plane, not a chisel.. but the same is true of plane irons as well:
15 September 2015 at 4:46 pm #130515Much appreciated. I think I have enough insight that I can put this wisdom to use in my shop and see If I can get sharper edges.
Thanks guys -
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