I have sharpened them but it isn’t exactly an easy thing to do.
It’s simpler to take them in to a sharpening service as they have the specialist jigs.
For a “bush” fix you will need a straight and flat bar to fit the cutter halves to. I used an aluminium extrusion from the scrap merchant. It was part of a door frame off a commercial building. I was actually looking for a piece of steel but this was flat in both length and width and provided support across the full width of the cutter. When I say flat, I mean properly flat not flattish, if it’s bowed in any direction you’ll make your cutters worse not better.
I had a piece of plate glass about a metre long which I used for sharpening big planer cutters. It needs to be thick and truely flat glass, not house glass as house glass has ripples in it. I got my bit from the glass bloke down the road, when he replaced a shop window he cut me a bit off. This piece of glass needs to be about 200mm wide. To the glass you glue a long strip of 800 grit wet and dry sandpaper off the roll using contact adhesive. My bit of glass sits on a thick chunk of mdf.
I separated the two cutter sections from the machine and thoroughly degreased them and superglued a cutter to the aluminium extrusion with the non-contact face of the cutter stuck to the extrusion. After applying a spray of water to the wet and dry paper I used the extrusion as a handle to evenly apply force to the cutter and move it back and forth across the wet and dry glued to the glass. I found that the edges were more worn than the centre so the aim was to get the whole cutter uniformly flat. I kept applying water to the wet and dry to keep the metal particles floating and not gum up the paper. You make a mess but I just mopped it up with old rags so it didn’t ever get past the edge of the glass.
Once one cutter assembly was uniformly abraded around the edge of allthe “teeth” I swapped to the other and repeated. Don’t worry if the centre section of the cutter is slightly concave, this is by design as it allows the outer sections to remain in contact under pressure..I went up the grits to 1200 and 1500, stripping off the old wet and dry paper each time. Once you’re done superglue releases using heat so I just used an electric heat gun and wiped the residue off the cutters with acetone. It’s then important to oil the cutters using a light oil before reassembly or they can rust.
It’s a bit fiddly but it does a decent job in a situation where you may not have easy access to a sharpening service.
Thanks Ironbark for for that very detailed post. I fear I have misled you when I realised I wrote "Trimmer".I actually meant Shears as in the hand tool. I hope they're a bit easier!
I can do scissors on my wet stone grinder using a jig. With properly constructed hedge shears you also need a jig but unless you’re a high end professional you’re very unlikely to have the equipment and expertise to achieve a good pair of mating edges. If you get the line wrong you’ll completely ruin them.
I do as Tyler has suggested. I have diamond laps that I use for touching up but every few years I take them to a pro for a proper regrind.. I do a lot of things myself however my good shears are beyond my skillset.
I've successfully sharpened cheap scissors with this knife sharpener I got marked down to $5.00 at Aldi a few years ago. I got a blunt pair I was using to cut sandpaper sheets back to cutting cloth again. It doesn't leave the best finish on the scissor blades but it works well.
It's also made a cheap Chinese kitchen knife that was previously hopeless, sharp enough to slice a tomato cleanly.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
Hi Ironbark, good to hear I am not the only one who does this. I see so many people say how easy things are to sharpen but I have never had the knack for it. The diamond laps give a decent finishing hone.
MF, I bought one of the aldi 4 in 1 sharpeners - knife, scissor, chisel, drill bits. Does alright but wouldn't want to use it on anything to good. Yours looks better though
I sharpen simple things like chisels and plane blades a fair bit. I have a setup that allows me to get them sharp quite quickly and to establish a sharpness that is both durable and straight forward to maintain. For this I use a wet stone grinder and an array of Japanese waterstones.
I do a fair bit of compound curve sharpening with axes and knives as well because I use them a lot. The first thing I sharpened, as a seven year old, was an axe. I had a grandfather who spent much of his working life felling trees and processing sawlogs so it was important to me to demonstrate proficiency with the tools he used, I’ve spent a lot of hours with files and waterstones.
There are a few things I won’t try and sharpen. Reel mowers is one, they’re waaay out of my skillset with the complex curves and the need for a uniform depth on each cutter and across the entire width. My wife’s good sewing scissors - I bought her a special set and don’t want to mess any of them up. My hedge shears, they’re a complex curved shape and are not flat along any axis. As we have a travelling sharpening bloke who comes through now and again and he gets them exactly right without removing much material at all, I feel much happier handing shears to him.
