Unlevel door lining

Keitai said:
You wrote above to clamp plane iron in lower jaws and chisel in top jaws. Have I done it wrong in photos? It seemed more natural to clamp plane in wider jaws. I put them facing in opposite direction too (as you stated).
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Sorry, mea culpa. :whistle: I wrote that the wrong way round - wider jaws hold the chisel iron, etc. as you correctly illustrate and plane iron measured from square edge as opposed to the chisel. It's been a long day, today...

Will correct my earlier post

Edit: Done!
 
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An additional thought: have you ever flattened the back of that chisel? It looks fairly ropey.
 
Keitai said:
Got it. Thxs. I used to think that the 25 degree (grinding angle) could only be made by using an electric grinding machine then what I now know to be 30 degree angle -the honing/sharpening edge (1-2mm) which is the sharp bit was produced on the stone with grits. But now I know both are produced on the stone by hand and no electric grinder needed.

I guess electric grinding stone is only used when chisel is dented or lopsided and needs serious grinding back.

So everytime I sharpen chisel - do 25 degree first then finish off with 30 degree angle. Not just 30 degree small bevel (end 2mm).
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JobAndKnock said:
120 grit would be the starting point if your chisels are completely fubarred. 180 grit will be OK as a starting point, but if your edges ar bad or badly chipped it will take a lot longer to sharpen to an edge. Low grit number = large grit size = coarse surface = faster removal of metal.


Yes, bit of white spirits (or better still lighter fluid or Evostik solvent) to soften the glue bond then peel off. Use a scraper if required. BTW, it is a "when" not an "if" it will wear out


The general use sharpening angle for plane (NOT planer , that is a power tool!) iron is 25° (extension 50mm), secondary bevel or honing angle is 30° (extension 38mm). Plane irons are clamped in the lower pair of jaws and the extension is measured from the body on the end of the jig with the rounded top.

The general use sharpening angle for chisels is 25° (extension 40mm), secondary bevel or honing angle is 30° (extension 30mm). Chisels are clamped in the upper pair of jaws facing the opposite direction to plane irons and the extension is measured from the body on the end of the jig with the square top.

I think you have confused extension with angle.

The main task is to grind the edges by working up through the grits. The honing bit, or secondary bevel production, should only produce a tiny 1 to 2mm secondary bevel the first time it is produced. Start this one with the 320 grit, then the 600 grit but only after working up through all the grits at the grinding angle. The iron or chisel can often be honed 3 or 4 times, sometimes more (probably only 5 or 6 passes on the abrasive each time), to "touch up" the edge between major sharpenings if you use this primary grinding angle/secondary honing angle approach


Wet and dry paper (otherwise known as silicon carbide paper) uses the abrasive silicone on carbide. This is a hard abrasive which is not particularly durable. That makes it faster cutting and more durable than the abrasives used for paint and wood. The downside is that it clogs relatively easily, hence the need for quantities of lubricant (in this case light oil, like 3-in -1)

The abrasives used for decorating are most often either aluminium oxide or garnet. These abrasives are relatively variable, i.e the abrasive particles shatter quite readily. That in turn means that sharp edges are constantly being generated on the paper, meaning that on softer materials such wood or plaster can be sanded fairly quickly. The downside of all this is that the abrasive wears out very quickly when used on materials such as steel.
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JobAndKnock said:
An additional thought: have you ever flattened the back of that chisel? It looks fairly ropey.
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It's an old chisel, that's why I practised on it. Shall I rub it flat on say 180 grit and work up like when honing but held flat(like u do to get rid of burr after honing)?

Bought a diamond stone as well. Will keep granite one on garage.

Is the chisel measured 40mm (honing) from square side and plane 50mm from rounded sound of guide?
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View attachment 220562 I read somewhere they go opposite ways
 
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Added some 120 grit wet/dry for grinding. My chisels are both new and very old. Marples of Sheffield . One is a bit rounded and another little one slanted. I honed this block plane blade on 340 and 600 grit only
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I've got some cheap chisels, recent ones are Amtech and some don't even have a name - probably Chinese - I have had them since the 80's and got them from one of the cheap homeware shops that sprang up. But the point is they sharpen well and hold an edge well, the handle is secure and has not split, so what's not to like?
 
So my questions are "Do you think you have you cracked the basic sharpening thing?", "Do you now understand about secondary bevels?", "Are your chisels now sharp enough to cut something more challenging than Lurpak?" and "How did you get on with the plane irons?"

PS it's "Marples" with an "M", not Harples.

PPS You still need to flatten the backs of those chisels!
 
JobAndKnock said:
So my questions are "Do you think you have you cracked the basic sharpening thing?", "Do you now understand about secondary bevels?", "Are your chisels now sharp enough to cut something more challenging than Lurpak?" and "How did you get on with the plane irons?"

PS it's "Marples" with an "M", not Harples.

PPS You still need to flatten the backs of those chisels!
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Marple, right thxs. They're very old and hard to read. I was told the big old one was a beauty by a teacher at evening class in college.

So basically pull out chisels 40mm from edge of honing guide to get 25 degree grinding angle. Then 30mm from rounded (same end) for 30 degree honing angle. Grinding work up through grits. Honing (sharp part) 340 and 600 grit. Push guide back and forth not pushing down too hard. Check sharpness with finger. Then put flat bit on grits work up through same to get rid of burr. I guess do this to flatten chisels like u say too. Not sure. What's the reason to flatten them?

With plane irons pull out 50mm from edge of guide (rounded end perhaps) for 25 degree them 38mm for honing. I guess this applies to all plane blades- smoothing, block, jack etc Not sure why you pull out further but still get same angle. These measurements off the top of my head dont have guide with me.
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The standard sharpening angle for chisels and plane irons is 25°. As you say this is the angle youneed stonework up through the grits to arrive at. Your bevel should be right the way through from the front face to the rear face of the iron or chisel. The lower the grit number the faster the abrasive cuts making low grits ideal for grinding out nicks and chips in the cutting edge

The standard honing angle is 30°. As you say you only need to work the last 2 grits because the bevel itself only needs to be 1 to 2mm initially. It is this secondary bevel which does mist of the actual cutting.

So why have a secondary bevel? Why not just grind everything at 30°?

If you think about it, when you grind at 25° then hone at 30°, giving just a 1 to 2mm secondary bevel, when the blade does start to go a bit blunt it can be "touched up" very quickly by just rehoning the blade. OK, so this means that each time you do it the secondary bevel does grow by 0.3 to 0.5mm or so every time you rehome it, but it does mean that providing you don't need to grind out a chip you should get 5 to 10 honings (shzrpenings) for minimal effort. When you work extremely hard timbers, e.g oak, antique pitch pine, teak, iron, etc. it is often the case that you'll only get 10 to 20 cuts between rehoning. When that secondary be el.grows to 4mm or maybe a bit less, then that's the time to regrind at 25° before adding a secondary bevel. The angles chosen aren't arbitrary. They are meant to allow general use in both softwoods and hardwoods whilst giving reasonable edge life and performance. Well, it works for me and saves a lot of time and effort

Properly honed you should end up with a tiny swarf across the edge which must be removed.

That said there are some chisels which only get a single (less acute) bevel and where a stronger edge is required, e.g. heavy mortising chisels. At this point, though, I wouldn't worry about these as you are unlikely to be using them just yet.

Why flatten the backs of plane irons and chisels?

Mist obviously, in the first case if you don't flatten the back before using a plane iron or chisel and there is any pitting in that back, you simply won't get a consistently sharp edge. Once flattened (to 600 grit) it is only necessary to buff up that face every few times you sharpen/hone with your highest grit paper in order to help keep rust at bay (a wipe over with a rag dampened with 3-in-1 oil ever time you hone or sharpen also helps)

Another thing to consider is that in a bench plane it is the back side which faces the wood, so it needs to be smooth and ideally semi polished. One more thing this does is to enable you to get a tight fit between the back iron and the iron itself (this needs to be a good tight fit to ensure that shavings don't jam betwixt the twain
 
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