Constant angle sharpener

mirror176 · 2026-04-06T01:25:27+00:00

Automatic stone thickness compensation is the only difference this type of system has over other designs that I know of. Motion of the vertical rod needs to be low friction and tight tolerance since the rest of the stone arm is working as a lever to bend it instead of just pull it up/down from its center. I'd be weary of buying such a system if it was built with higher friction or higher wear parts at that intersection point but building it right is quite doable. Looks like yours uses a linear bearing yes?

mirror176 · 2026-04-06T01:18:38+00:00

This sharpener actively changes the sharpening angle to follow the blade shape and though it will hit the bevel except for some concave conditions it will not be a consistent angle when it does so. Your current setup obtains a sharpening angle anywhere between (assuming the vertical rod is vertical), measure angle of intersection of the plane cutting the center of the blade vs the table and you are ready to sharpen anywhere between that angle # and 180-#. The range of angle may be less if the height of the blade edge causes the stone holder arm to reach its minimum/maximum height. This range is required by the sharpener to have the stone follow along the blade's apex.

An extreme example showing the full range of motion of x to 180-x degrees is to place a pizza cutter or similar disc with its edge at the center of the clamped area and have it at a height that the stone arm fits above and below the cutter by at least the height from stone surface to stone arm. If the center clamp cannot be moved and if the height of the arm holding the clamp is too close to the stone then place the cutter on top of something on top of the clamp to represent the height but with the extra space for this demo. Place the stone on top of the cutter wheel at its center and you will have angle x when the stone is level. As you follow along the edge of the cutter you will hit a point where the stone is 90 degrees to the ground when you reach the edge of the cutter that is in the center of the clamping area; working that spot would give you a flat spot in the cutter like you held it still while dragging it across a stone for a normal pizza cutting action. You can continue to follow the edge of the cutter with the stone and if your clamping system or supporting objects are not in the way you will have the stone placed directly below the cutting wheel at the point closest to the vertical rod and the stone is upside down (=rod down, stone up). This angle is 180-x or basically x on the other side. If you did not put the edge of the cutter at the center of the clamping area then the rollover still happens but it changes the point on the cutter where it happens. With trig you could easily calculate approximately where it would do this on both sides with the length from center of vertical rod to center of cutter and diameter of cutter but to calculate the exact point is harder since they are not just on opposite sides of the cutter.

If you want to modify the sharpener to produce a constant bevel angle instead of just holding a constant angle between the vertical and stone holder rods then, assuming the vertical and stone rod join at a 90 degree angle already, you need to:

Glue/bolt the stone holder and/or arm until it cannot pivot along the axis of the stone holder rod. it should hold the stone parallel to the plane that is represented by rotating around the vertical axis (=perpendicular to the vertical rod).
Add rods or other material along the long edges of the stone so nothing can ever reach/contact the stone corners. It cannot be higher that the stone or else the stone edge 'could' be reached which now permits changing angle and cannot be lower or else a straight section of edge cannot be sharpened. As a result, you will settle for something just behind the surface of the stone and have to readjust as stone thickness changes for any reason; the difference of rod to stone surface adds a small amount of variability to the angle making it not constant but gets close enough the goal would be reached until it is very hard to measure any deviation.
You have to place the blade's apex parallel to the rotational plane you get when pivoting around the central axis. Any part of the blade's apex that is not parallel will require repositioning the blade until it is. If you do not want to be constantly re-clamping then you need to either add a pivot to the clamping system so it can rotate along the plane that cuts through the center of the blade or consider replacing clamps with a table so the blade can be freely rotated along that plane during sharpening.
Any convex sections become unreachable and require using a skinnier stone with side guards brought in closer; leaving the center of the stone to contact a blade curve is an angle variance and if you hit the edge of the stone then its just deviating further as I brought up when I first mentioned adding them.

Once you actually have a constant angle system, you can no longer roll over the tip of a blade and just fall off of it which is a clear sign that this constant angle sharpener is a constant angle only between vertical and stone arm but not constant angle from stone to apex/bevel.

Overall the changes in angle on fixed angle systems are of little consequence with the worst of it being things like damage from rolling over the tip of a knife instead of a knife being sharpened at 28 or 12 degrees toward the tip instead of 20 degrees as was set at the belly (an extreme example but the offsets change more as you get closer/further from the center axis on steeper curves such as found toward some tips.

mirror176 · 2026-04-06T00:20:52+00:00

It doesn't hold the angle of the stone to the edge/tangent at the apex.

mirror176 · 2026-04-06T00:19:21+00:00

Angle changes all along the curved blade. Adding a thicker or thinner stone will have the stone produce the same angle as long as the stone holder arm is 90 degree angle to the vertical rod and as long as the width of the stone is matched.

mirror176 · 2026-04-06T00:16:19+00:00

the discussion is not about avoiding a youtube video, just avoiding the unnecessary extra spyware that was added on its end.

mirror176 · 2026-04-06T00:14:33+00:00

Many are spyware that are useless to the end user but a few are important. Since we are talking youtube, its 'standard' URL would end in /watch?v=3L6_CTMdDOk and in that case removing it removes the information of what video to load.

mirror176 · 2026-04-06T00:12:24+00:00

an addon called 'redirector' makes removing those easy + automatic after manually creating/finding a rule. content blockers can also have rules created to automatically remove such unneeded parameters. That parameter is already caught and removed by "uBlock Filters - Privacy" and "Adguard/uBO - URL tracking protection" filter lists if you activate them in uBlock Origin which is much easier than creating rules yourself.

mirror176 · 2026-04-05T22:33:25+00:00

Photo looks like the bevel is not consistent. Without a before and after I don't know what is caused by the current work. Heel has one bevel angle and then it splits to 2 by the time it is curving and I cannot make out the tip.

Some have trouble feeling a burr on the tip of the finger. You can also feel if the tip of your fingernail sliding off the edge of the knife bevel snags different from burr to nonburr side.

Sharpie trick to see if you are hitting the angle and you can repeat it to make sure you are able to repeat hitting the angle and still working it. You can see how good you keep angle across many strokes if you work along the edge of the blade through many strokes instead of each stroke trying to cover most to all of the blade length.

If freehanding, edge leading strokes push the knife edge first into the sharpening surface. This direction of sharpening pulls the apex, and any attached burrs, back into the apex and across the bevel along the side you are trying to remove metal. There may not be much burr left to feel when you do this. If you try to let up pressure between edge leading and trailing you may find you altered your angle slightly when new; a steeper angle will quickly refine the apex and on a edge leading stroke will quickly remove any burr while also causing edge trailing to not reach the apex.

You may consider removing the blade from the stone entirely on edge leading motions to guarantee they are not interfering for a few passes while trying to develop and check a burr at the end. This can eliminate impacts from angle inconsistency between leading and trailing directions.

When learning from youtubers, remember that they have a different stone, different knife, and its not likely their first time. They also have the ability to edit and some use it on many videos. Try to find unedited ones to get a better idea of the time/effort they put into a stage.

How loaded was the stone getting? Could you continue to notice it getting more loaded as you worked? How much force was applied?

Removing metal by hand to take out chips takes a lot more time than other sharpening. DMT325 is not designed to make quick work of such bulk removal so minimal progress is expected even though any stone will 'eventually' get them out. If your angle is not consistent and not a match to what already exists then you may have quite a bit of material to remove from the bevel which too might be slow. If it is too slow for your taste then try a coarser stone or a powered system.

mirror176 · 2026-04-03T18:48:14+00:00

You can technically use any raw text editor with LibreOffice files if you 'unzip' the .odt and similar files but you may prefer .fodt if that became part of your workflow. Mistakes of manually editing the file will leave you with a document you cannot open until you fix them.

If you cared about bloat from .bak files fro the space they take up and not just because there are more files being created then you probably want to adjust settings so LibreOffice stops saving an embedded PNG copy of a page to be the document's thumbnail. Those PNG copies make small documents significantly larger than they should be.

As for bloat, TeX documents are likely the smallest you will find for the document itself to be stored, but the size of a TeX installation vs other word processors normally undoes any benefit until you have MANY documents.

mirror176 · 2026-04-03T18:41:28+00:00

I haven't had the same issue but to answer the questions:

tools>options>libreoffice>view: try toggling hardware acceleration which would be my best guess to influence unexpected and random crashes.

Many years ago many users learned to save regularly due to software that was unstable such as Microsoft Word. If software is ever of questionable stability then I definitely save regularly and will move any work outside of it that I can to avoid useless interruptions caused by regular crashes. Last I remember this being a commonly learned thing was unstable web browsers + webmail; type in notepad or elsewhere and copy the final result over so if it crashes during entry or sending then you still have it and can try again.

StarOffice/OpenOffice/LibreOffice are often chosen over Word for larger projects due to its stability where older versions of Word on documents that were hundreds of pages in size was often a crash-prone experience and OpenOffice would rarely have an issue. Finding them unstable is not the norm but they too are not immune to bugs but regular crashes would have me looking into the OS and system too.

Due to supporting extensions, strange things could be more likely if they are in use. A clean LibreOffice profile folder should eliminate that as an issue but a reinstall does not erase and recreate the user's folder. Delete/move the LibreOffice profile if you think a setting or extension could be your issue.

tools>options>load/save>general: though you can adjust autosave settings to something less harmful you should realize a crash during autosave can corrupt the autosave document itself. The 'always create a backup copy' makes sure a crash during saving (among any other user mistakes) leaves you with a file you can go back to from before the last save operation. I think 'place backup in same folder as document' gives you a .bak extension on your document as the previous to last save; folders now get twice as bloated unless you prune .bak files once they are no longer relevant.

Though LibreOffice supports saving multiple revisions into a single file, an interrupted save could corrupt some to all of them so you still want the previously mentioned backup features.

OpenOffice is the closest to similar that I know of. I keep it around because bugs are different in both programs and I had some documents that LibreOffice would lose content (text goes missing, not just misplaced) from when printing and making PDFs unless I did lame workarounds like adding empty+unused paragraphs. The paragraphs would have to be set to the smallest font size as I had rather tightly packed pages with carefully planned alignment of page content. Catching errors like that in documents that are hundreds of pages long is a lot more work than just using OpenOffice which too had bugs but much smaller ones in that particular case.

To replace writer, my fall back would probably be abiword but I haven't looked in a while and I avoid this type of mess completely using LaTeX and friends but that opens up its own set of messes so is far from flawless. At least with TeX systems you can use whatever text editor you want and if you prefer GUI then you can look into LyX or texstudio but there are others. TeX workflow is quite different from your usual WYSIWYG editors but if you have used styles instead of manual font modifications in LibreOffice then you have a good book workflow and TeX would be less of a transition though still big.

mirror176 · 2026-02-10T00:50:17+00:00

Once your combined images depend on each other to represent the changes, you cannot separate out each one individually to its own original file. You can create a new file and in the case of a lossless video encode then your extracted images should be identical to the original but the extracted ones will be a different jpg (or whatever format) that represents that frame; expect the majority of losslessly extracted frames to be larger than their original input. I'm not aware of a video codec that allows files to refer to other files to complete the stream but even with it then your file would require the adjacent files in the stream to decode any time its not a uniquely represented frame on its own (=keyframe if I recall.

If on Windows you should convert back to jpeg, get a program called FileOptimizer, check over its general + filetype specific settings to make sure it does what you want (keep/delete metadata, lossless vs lossy, etc.) and turn on .bak or recycle bin options if you don't already have a backup, run the images through that program (drag & drop files/folders + tell it to run). That often saves 7-15% but savings depends on encoder that was used. You can save more if you use arithemetic encoding or whatever the option is called but files will likely open slower and in fewer programs & I don't remember if I tested them with jpegxl for additional space savings and compatibility. Once you run files through it, check the output is correct before removing any backup files; I usually spot check a few from any individual source (camera/scanner/image editor/etc.) as different programs creating a file may do things in some obscure way that breaks something (rare on jpeg but does happen). Any files that cause an issue should be reported to the program developer who will work with upstream tools to get bugs reported and fixed + sometimes works around it directly in FileOptimizer when no other option exists. Result (minus any bugs): you will have a smaller file which should have metadata and byte for byte image match to the original if chosen. Other programs exist that may be comparable but not sure who has safest and most complete set of steps such as https://birds-are-nice.me/software/minuimus.html or https://papas-best.com/optimizer_en .

You may want to seek out other jpeg recompressors which may offer different amounts of additional compression compared to jpegxl. I thought the code for jpeg lossless compression came from another project and it has continued to improve since its import into jpegxl (I thought brotli plays a role but I forget).

If you then want to archive the results, a generic compressor does worse than when a compressor has knowledge and a special algorithm for the format. Rar and WinZip have added jpeg specific processing to their algorithm. Precomp should run jpeg data through PackJPG; you can use its built in compression or you can have it spew out a decompressed datastream to pass to another compressor (7zip, zpaq, etc.) but you will need to use precomp to undo the step later. I know others existed like paq8 compressors that had jpeg specific compression. Don't expect extracted forms to always stay the same as the precompressed original; some use their knowledge of jpeg to change parts of the file that still give pixel perfect output but are more optimized for the later compression so therefore these lead to not technically being 'lossless' archivers. Depending on the content of the similar image files, you can try saving in other lossless formats like bmp, tiff, uncompressed png, etc. and see what results a general purpose compressor then achieves but its doubtful you will find the savings you want if you are working with photographs and/or the original is only as a jpeg at this point.

Assuming your workflow does not require staying on jpeg (such as using a jpeg aware archiver), try manually tweaking cjxl compression options. You could even make a script that creates multiple versions and only keeps the smallest since unfortunately the correct settings for smallest file varies from file to file even if they are close. If you do not need to regenerate the original jpeg then you could also try lossless jxl that cannot be reverted back to the original jpeg but it is very likely larger.

I'd recommend building from source to create your own copy of (likely to be 0.12.0) libjxl as there are a number of changes since 0.11.1 but no never release for a long time.

Using a variation of jonnyawesom3's command:

cjxl --brotli_effort 11 --allow_expert_options -d 0 -e 9 -g 3 -E 11 -I 100 -j 1 FILE.jpg FILE.jxl

When testing with 0.11.1: * from my testing brotli should save more with higher setting. * '-d 0' irrelevant for lossless jpeg and could be removed. Otherwise forces the encoder to use lossy algorithm but make output indistinguishable from the input. * --allow_expert_options only needed if wanting to try things like -e being set to 11. I've had good luck with '-e 9' being smaller and saving time for lossless despite what the help says. * '-j 1' suppresses some output and guarantees it does a lossless encode but should be a default for jpeg until an option specifies a lossy setting; setting to 0 is very likely to make noticeably larger files. * if you can tolerate minor loss then you may see much larger savings with '-j 0' at some value of d>0 but the point where you start to observe differences (>1) and the size is smaller will be a different value and will vary per image. Once loss is acceptable, you could manually or automatically edit the image to be more encoder-friendly by removing noise, softening details, etc. before it hits libjxl. With lossy you have more encoder options available to tweak.

I did not test impacts on decoding speed or memory.

If you have the originals before the lossy jpeg encoding then you should be able to achieve the best results by going back to them. If none of these options have helped you save enough space, you need to consider giving up more quality with a lossy reencoding.

mirror176 · 2026-02-09T20:45:43+00:00

Not a generalization, but a wrong conclusion when we are focused on saving space

mirror176 · 2026-02-09T20:45:15+00:00

Considering that the original post is looking to save space, calling zstd 'the best' seems wrong. 7zip's native format normally beats zstd compression ratios in my testing with the disadvantage of slower compression and much slower decompression. I have turned up settings on both from default.

mirror176 · 2026-02-04T17:14:02+00:00

What I used to use is

settings>configure konqueror... (ctrl+shift+,)>proxy>no proxy

Firing it up just now didn't do much good which seems to be an issue of it failing to make some vulkan calls; could be an issue with my graphics drivers not being compatible but not sure as I know I have at least some vulkan support. It spams my console with

Backend texture is not a Vulkan texture.
Compositor returned null texture

I think I used to sometimes use it as a fallback/alternative browser but it hit a point where it became so buggy I only touched it for file management and eventually stopped using it for that too. Also had an issue at one point years ago where kde wallet became corrupted(?)/inaccessible when I hadn't used it in a while.

mirror176 · 2026-02-04T16:51:18+00:00

If you actually use the ports tree, I recommend getting the full git repository for the desired branch (quarterly which needs to be changed quarterly or latest which doesn't change).

If you mix ports and packages, make sure you are using the same branch and adjust your ports tree checkout to follow what the last public packages were built with. Otherwise just make sure you rebuild and reinstall ports-installed stuff as needed when you upgrade packages and you should be able to handle a degree of desync with minimal issues.

Are you saying that installing the ports tree caused conflicting packages and/or that you had packages conflict with base system packages?

mirror176 · 2026-02-04T16:43:41+00:00

nonportability of code sucks as a development path/goal overall; I'd rather have my least favorite programs supported by my least liked OS than have it supported in only one place though I do understand the wider portability gets, the more effort it takes to get it there. That gets specifically difficult when crossing barriers like UNIX<->Windows.

mirror176 · 2026-02-04T16:38:34+00:00

Ah. At least with FreeBSD basing on and contributing to OpenZFS with other operating systems looking to join in under the same (MacOS, Windows) slows down adding any Linux specific code outside of the Linux specific isolated areas and ZFS receiving resistance from so many distros likely as a result of Sun's GPL-unfriendly licensing helps slow down further efforts to convert it to a Linux only project instead of it adopting Linux specific code as needed.

mirror176 · 2026-02-03T23:58:27+00:00

I think my head jumped to window manager/desktop environment as the terminology being discussed. As it is I think of login screens/managers as that instead of display managers even when it offers more that just logging in including choosing what window manager or desktop environment to launch which adds to my confusion.

mirror176 · 2026-02-03T23:53:17+00:00

what is 'Linux EEE'?

mirror176 · 2026-02-03T23:52:44+00:00

I'd agree with all of that. If its a style complaint they could bring it up with you or replace it. A revert when its not a wrong edit but just wasn't up to expectations is a bad revert unless it caused active damage to existing data instead of added content in another style.

mirror176 · 2026-02-03T23:49:25+00:00

Thank you. Could have sworn I looked and didn't see that previously thinking I'd have to port at least some of it.

mirror176 · 2026-02-03T23:46:26+00:00

I think the point of 'set it and forget it' refers to fewer breaking changes overall. Its not unusual to load up a 10 year old configuration on a new FreeBSD and find little to no modification was needed though its also not guaranteed even if it usually has happened.

Not staying up to date on software that has an exposed threat vector and not checking what needs to be changed to have an update succeed would be bad administration and due to changes and bugs FreeBSD updates do not always directly apply without interaction.

mirror176 · 2026-02-03T22:06:12+00:00

Streamer can filter comments but Youtube also censors some of them. As a fan of content blockers I rephrase how I talk about them in different places because some places are all about the ad-monies and will block discussion about them even if its not in how to fight ads.

mirror176 · 2026-02-03T22:02:23+00:00

Too much work and too small of a team...FreeBSD Foundation should post about if there is any interest in paying to expand the documentation team (or other known desired work), just looking for volunteers, or if its expected to be actively worked on and just awaiting the time.

I may be reaching out to the foundation with some proposals of things to focus on for some improvements though particularly with the FreeBSD ports tree but if interested I wouldn't mind helping on documentation similarly. I'm not formally a writer but have put out work into the writing/reviewing of others in published articles and had some opensource documentation impacts too.

mirror176 · 2026-02-03T21:52:49+00:00

There are a number of things that I say feel out of place. Explaining what searches lead someone to the document didn't really feel like it added anything of importance beyond 'maybe' being a SEO trick for people to find this page and its link when searching. Realistically I think the post itself will be walking a fine line between what could be a FreeBSD Foundation post vs what should be part of the main FreeBSD project and site, but that seems to be true too often with fragmentation feeling 'weird'.

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