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Discussion Starter #1
TLDR: I've rounded my plane iron and I can't get it sharp, yes I have sharped the bevel and the back

Whole thing:
So I got my first hand plane. Its a Sargent 409c. I got it all cleaned, tuned up (as good as I can for my first time around), and flattened. The the plane came with an iron that was sharpened at 45*. I wanted a more traditional 25*, so I started with my bench grinder to change the angle. I thought I did an okay-ish job getting the angle I wanted (spoiler alert: no I didn't), but I will be upgrading my guide for next time.

After getting the ~25* angle on my bench grinder I used a honing guide on sandpaper adhered to a granite scrap off I bought from a counter shop. I started with 80 grit and went in series with 80, 120, 240, 400, 800, 1200, and then finished with a strop I use for my cut throat razor. The iron wasn't sharp, at all. It was highly polished on both sides, but would not bite into anything. I looked at it more closely and noticed that instead of having a sharp point I had a incredibly small flat "nose" at the point of the iron.

Went back to the sand paper and started again at 80 grit with the honing guide and also figured out that when I had set the angle on the bench grinder I had slightly chamfer-ed the iron. I added a strip of 40 grit sand paper on the granite and flattened the edge of the iron while stopping every 2-5 strokes to compare the iron to a try square to make sure the edge was flat and at the correct angle. After I got that done I went back to using the sandpapers listed above

I have been using mainly 80 grit sand paper, and then going to 120, and 240 to figure out if I had a proper point on the iron, but it still isn't biting anything. I have tried working my way up slowly through the grits until I got to 800 to see if I just needed to get the iron edge sharper to bite, but that has not worked either.

I have now been at the recovery stage of this for 4 hours (so not including the original tune up, sharpen, etc.) and could use some guidance.

Thanks in advance for the help
 

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Polished faces but no point on the edge is a sign that you didnt spend enough time at the lower grit and actually form a point. While sharpening, you should feel a burr on the opposite side of the edge youre sharpening that extends all the way across the edge before moving to the next grit. That burr is a sign that you have the edge actually going down to a point, and thats the same no matter what shape youre sharpening.

If you already have the back side of your blade flat and polished, your work is half done. Go bac to sharpening the bevel, starting with 220. Personally i find anything lower than that to be way too coarse for sharpening needs in 99% of circumstances. Sharpen the bevel, making sure to keep the angle consistent, and keep going until you raise that burr across the entire edge. Dont touch the backside yet. Repeat through the grits, dont skip any, all the way through to 2000. You can stop short, but the finer the abrasive the finer the edge will be. After youve hit your highest grit, move on to the strop, but again, be careful about matching the angle, and go with a light hand. The edge should already be sharp at 220 grit, everything after that is just polishing and refinement. If your edge wont cut at 220, moving up through the grits will be a waste of time. Youll be asking a finer grit to remove too much material and either use more abrasives, or get a sub-optimal result
 

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Great explanation, @epicfail48.

Some things I'd like to add:
- How did you test if the blade cuts? Did you do the paper slicing test? The arm hair test? Or did you install it in the plane and try to cut wood? Since it's your first plane, I'm wondering if it's incorrect setup of the plane, and not the blade itself.
- I'm assuming you used lubricant and didn't overheat/blue the iron while on the grinder? If you blued it, it'll be brittle and not hold any type of edge during or after sharpening.
- I agree with epic's assessment that 220 is about the lowest for sharpening. But 80, 120 are good for final shaping, especially after a grinder.
 

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I would recommend hollow grinding the bevel. I do this on all my chisels and plane irons. It enables you to achieve a sharp edge much easier and quicker.


Side note, ease the corners (not camber) to reduce plane tracks.
Personal preference, but I use water stones, finish at 12,000 grit. I don't know what this translates into sandpaper.
 

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Discussion Starter #5
So thanks for the help everyone. Here's what I did to fix and the conclusions I came to:

1) The below 220 was right. When I was leveling and flattening the bevel I was making strokes both directions. At lower grits at appears that doing so continued to blunt the point of the iron. I sharpened a bit starting at 120 doing pull laps only to finish shaping the iron bevel to a point.

2) For tools I typically just use sandpaper. It has worked on my chisels for years. But I also have some waterstones the wife bought me after I started using a cut throat razor. I used the 1000 grit stone until I finally got a proper burr across the edge of the iron.

3) At this point there was a good edge on the iron, but it wasn't polished so I went back to the sand paper and started at 400 grit, then went to 1000 grit. Then finished with a strop.

At that point I was able to cut a loosely held piece of paper. Loaded the iron into the plane and it worked as expected.

@epicfail - Thanks for the help
@awesomePossum74 So I didn't do much in the way of those testing steps. I could run my finger across the "edge" of the iron and you could feel it was flat. It felt so flat that I drew my finger along the edge and it wouldn't cut my skin, and I could further feel how flat it was. It was pretty pointless to try those tests; at that point I could have glued a tongue depressor to the iron and used it as a fan because all it was going to do was blow a piece of paper around instead of cutting it. Also, I had not blued the iron while using the grinder and specifically took breaks and used a fan to cool it, but I also did not do a good job of shaping the iron. The tool rest on my grinder has left a lot to be desired. I'll probably make a quality rest that will allow me to maintain the angle of the iron into the wheel before I attempt that again.

In the future I will probably only used 120 and down for shaping, but I'll probably start doing a pull only lap when I get close to finishing the shape and then bump to 220 to start sharpening with laps going both directions.
 

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I like those "Japanese" waterstones, but they dish quickly. You need a way to flatten them. I use an extra course diamond stone to flatten waterstones. I suppose sandpaper on a flat surface would work, as long as you clean every bit of the sandpaper grit off the waterstone before you use it, to avoid course scratches.
 

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One important point I forgot to bring up about sharpening with sandpaper, pull, never push. When you push, no matter how you have the paper secured to the substrate, the paper can bunch up on the leading edge and mess up your blade edge. If you're doing really rough shaping, trying to take a nick out of the edge say, pushing won't hurt, but once you start going to sharpening, pull only.

I'll also say I may be one of the only people to advise against grinders for sharpening. They take off metal fast, but too fast in my opinion. Going by hand is slower, but more of the metal you paid for stays on your tool. Same thing with hollow grinding, another thing I absolutely hate. Get yourself a decent honing guide, the Veritas one if you can swing it, and don't chip your chisels by scraping gaskets
 

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I'll also say I may be one of the only people to advise against grinders for sharpening.
You're one. I'm another. Partly for your reasons, but also because I prefer the feel of doing the work myself. It's not as messy (flying metal shards and fluid going everywhere), and there's no issue with bluing. Also, in the OP's case, no worries about a weak tool rest.
 

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One important point I forgot to bring up about sharpening with sandpaper, pull, never push. When you push, no matter how you have the paper secured to the substrate, the paper can bunch up on the leading edge and mess up your blade edge. If you're doing really rough shaping, trying to take a nick out of the edge say, pushing won't hurt, but once you start going to sharpening, pull only.

I'll also say I may be one of the only people to advise against grinders for sharpening. They take off metal fast, but too fast in my opinion. Going by hand is slower, but more of the metal you paid for stays on your tool. Same thing with hollow grinding, another thing I absolutely hate. Get yourself a decent honing guide, the Veritas one if you can swing it, and don't chip your chisels by scraping gaskets
I use the Veritas Deluxe Honing Guide Set for chisels and plane blades. With a nice set of diamond stones, it isn't cheap, but should last a lifetime. I recommend the Veritas guide set.

I use a Grizzly wet grinder for turning tools, like gouges. I also use it for the skew chisel. It creates a hollow grind, but the wet grinder is very slow to take off metal, like creating a fresh bevel angle.

I would like to find a reliable way to hold the skew chisel and the parting tool so I can sharpen them on the flat stones. I bought the Veritas Skew Registration Jig, but it isn't suitable for the 70 degree angle on the skew chisel. I have not tried to sharpen the parting tool yet. I am not skilled at freehand sharpening.
 

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Discussion Starter #10
The kid I have is from Norton. It can with a 3rd stone specifically for flattening the waterstones. You just rub the stones on the flattener a few times. It only takes a couple seconds.
 

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One important point I forgot to bring up about sharpening with sandpaper, pull, never push.

So I have never had that problem. When I sharpen with sandpaper I have always used some type of strong(ish) adhesive, like 3m 77, to attach the sand paper to something flat. I've used a couple small peices of MDF glued together, tempered plate glass, and now I am using a granite scrap. As long as you lay the sandpaper flat, like it is supposed to be, its not moving anywhere. And you can sharpen twice as fast.
 

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So I have never had that problem. When I sharpen with sandpaper I have always used some type of strong(ish) adhesive, like 3m 77, to attach the sand paper to something flat. I've used a couple small peices of MDF glued together, tempered plate glass, and now I am using a granite scrap. As long as you lay the sandpaper flat, like it is supposed to be, its not moving anywhere. And you can sharpen twice as fast.
The problem is give in the adhesive and the paper backing, not the paper being loose. Flex inherent in the system will let the paper bunch up by a very tiny amount. Not much, but enough to foul a good edge
 

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Back up check -> You have the iron installed correctly? Might be a silly question, but something I fumbled with when I first started using hand planes.
 

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Sorry up front for such a long post. Much is written about sharpening and much is right and works. Angles are a compromise between ease of work and edge retention. Geometry of a specific tool and the working qualities of a specific species have much to do with sharpening decisions. I have been at this a while, as I am sure many of you have, and I have tried many ways.

Here is what works best for me. Plane blade edges should be shaped (cambered) appropriately for the task the tool is to perform. Different craftsmen have their preferences and they all work. For older tools I start by evaluating a blade for condition. Some blades are used up or may be in such bad shape that they must be replaced. Older manufacturers sometimes hardened the end of a blade so that the hardened section may be used up and the blade has to be re-hardened or replaced. Really old blades may have had a piece of steel forge welded onto it and if that is gone then the blade must be replaced or restored. Minor pitting on the back of the blade can sometimes be ground out by flattening or by introducing a "back bevel" using the "ruler" trick. If the tool is used for fine work it must be replaced if the pitting is still present at the edge or regulated to doing rough work. If the tool is used as a scrub or jack plane and if the work is to be further worked then the imperfections thus introduced do not create a problem. The back should be flattened and polished. Back bevels, if present, should be done in a manner to qualify as flat and polished. Backs are normally worked on a 400 grit diamond stone and evaluated for flatness after a few strokes by examining the scratch pattern. The blades are then worked flat, or minimum back bevels introduced, as necessary. The blades are then moved through to 1000 grit stones before attention is given to the bevel. I carefully hollow grind the bevel as necessary, to square the end profile(flat or cambered) to the body of the blade. The grinding is done by eye using my finger against the grinder rest to maintain position and frequently dipping the blade in water to prevent overheating. I only grind for shaping the camber and to establish the primary bevel. I know of no device designed to create or stone plane cambers and thus they have to be done by hand and eye. Primary bevels do not have to be "perfect" and can be of a general range of approximately 25 degrees. After I am satisfied with this step, I proceed to my diamond stones (other stones, and abrasive papers can and have been used) normally starting with a 1000 grit and feeling for the bevel, stone the blade by hand. Because you are ideally hitting on the edge and back of the bevel a bright line will quickly develop indicating where the edge is being fully developed. stoning continues until the entire edge (not the entire bevel) is being engaged and a burr is being pushed to the "flat" side of the blade At that point the blade can be moved to finer stones as desired, at least to 1200 grit in my case. Finer stones can be used but in my opinion, it is difficult to justify the additional time and money if the blades are to be honed/stropped/polished. Micro bevels are recommended for hardwoods and may easily be introduced by simply raising the blade a few degrees during the final stoning of the bevel. If the blade is being used for smoothing operations then the corners should be eased, or rounded. Some craftsmen choose to introduce an extremely small camber to the edge at the final grit stone by simply applying additional pressure at the corners for a few strokes. Attention must then be given to the back of the blade to eliminate the burr, being sure to use the "ruler" trick as necessary on flat edged blades. After alternating the sides being worked the burr will be reduced but may not be completely eliminated. Very hard modern blades may not develop burrs that are readily noticeable but if good technique is used a tiny one will be present and subsequent efforts will indicate successful sharpening. Remember that after the edge is established, all of the efforts simply are to polish and refine the edge and remove the burr.
After using the stones most blades will continue to have a small detectable burr. Finer stones would only serve to polish the edge and a cheaper technique is to simply strop or buff the blade. I prefer to lightly buff the faces (flat and bevel) using a buffing wheel charged with fine polishing compound. Alternately, any strop or hone, including leather, or MDF may be used provided it is simply used in a manner to refine the edge without overheating the edge or significantly rounding the edge and to eliminate the burr. Testing is performed by installing the blade, adjusting tool and using it. The planed work is then inspected for any indication of tool marks indicating an edge flaw. Generally any flaws found at this stage (if any) indicate that additional stropping is needed. often times, subsequent inadequate blade performance (after use) can often be greatly improved by simple additional honing, reducing the need to return to stones. Grinding need only be performed if reshaping the blade for other uses or if the tool becomes damaged. Guides may be used for the stoning process if desired but adds little to the finished edges ability to cut. They only help to establish a more refined geometry to the bevel of a straight edge. Just remember that it only the extreme edge that does the work and the entire process (without grinding) should only take about two or three minutes at most.

I do sometimes use guides with stones just to make sure I am not getting too far off the desired primary bevel angle but, seriously, a few degrees one way or the other makes little difference in tool performance. Don't be put off of the craft because you can't achieve the "perfectly-shaped bevel" and wet-and-dry paper will work just fine too so don't feel that you have to spend a lot. The toys just make it a little easier. Have fun.
 

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From experience, don't assume the Norton flattening stone is flat. Easily corrected with coarse grit paper.


The key to sharpening is don't progress to the next grit until you feel a burr. That, plus a perfectly flat back and you should be good.
 
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