those look like decent quality ones. How much are you paying for blades? since I started using little jointer blades in mine I have gone through quite a few. I have to replace them so I have been just saving the "dull ones" but they are still basically razor sharp so I finish them off as paint scrapers. but supply is limited.
Its nice to be able to change them more frequently but at the prices I seem to have to pay at the box store it gets pricey. sometimes I just sharpen them. using a diamond stone and touching them up by hand is a good idea.. or you can use a carborundum grind stone and that will sharpen them. If I did a lot I would make a jig to do it.
Ive sharpened my own jointer blades on the tablesaw. I just put the stone in the saw where the blade belongs and made a little wooden jig so I can hold the blades flat on the table up against the grindstone and shift the blade back and forth.. it works pretty well if you just dont want to keep dropping money at the box store. this method also leaves a hollow grind which will make touchups with a diamond stone freehand easier...
the problem with sharpening those little blades on a grindstone is you need a fixture to hole them or you just burn your fingers as they don't have a lot of material so they heat up fast. If you are out working than it's not worth sharpening them but for the thrifty homeowner there are ways.
Often I also have to change a lot of planer blades, like in big thickness planers.
this brand, Tersa is the best. the thing about these ones is they have sort of a key and they slide in from the edge of the cutting cylinder. it's really easy to slip the old blade out and a new one in and since no changes are made to the blade height I don't have to adjust them. some of the older machines take a long time to fiddle with the blades to get them set up just right , but the Tersa ones are a brilliant idea..
well I started looking at this.. I often just chuck those long blades and they are like 3 feet long. and they are carbide.. they are double sided.. well what I found is that Tersa does make a blade holder. Its easy to chop the planer blades of to the length you want with a demil or a zipdisc on and angle grinder. the ones from thickness planers dont' have an added little block thing.. they show new scraper blades but they are still too expensive for my budget. . I want to re-use the old tersa ones, when I pull them they are plenty sharp for scraping paint.
I think Ill try to make a holder for the tersa knives and start saving them for scraping.. at first I figured they would be too hard to hold. they have no holes in them. but I can make a clamp style holder.. a blade 2 or three feet long will make a bunch of paint scrapers.. Maybe it would be nice to be able to change the cutting angle slightly? a shop made tool could perhaps have a tilt that can be locked at different angles.
the blades and holders tersa sells might be OK too but I'm trying to recycle them and avoid the cost. It looks like their replacement blades have a little tab which makes them expensive.
anyway here is the link to the Tersa scrapers
https://tersaknives.com/collections/ral ... li-shark-lthese are the ones i want to make a holder for.. it looks like the carbide ones 660mm long are $220.00 each but they go in the garbage if they get a nick or even slightly dull. - wow expensive blades. that might be for a pair, they come 2 in a pack.
https://tersaknives.com/collections/ter ... 4070873414I think a lot of people start off with a sharp blade and persevere and half the time they are still using the old blade which is too dull to work well. the paint is pretty hard on them never mind nails.
Just clean the blade and then run a fingernail along the length of the blade. If you feel nicks , it's spent.
But I think what happens is that a lot of us go well it's still working and continue way longer with the dull blade,, because a new blade might be 10 or 20 bucks. This is a lot more work and fatigue but you can easily dull a blade in 15 minutes of scraping.. and that adds up. I think finding a source of really cheap sharp carbide material just makes sense especially for those who want to do like the side of a house or something.
If you are scraping finished wood, like a window sill or something, ahving a sharp scraper means you can get the paint off without really scratching the wood up. - of course depending on the kind of paint and your technique.