There are a number of different substrates that are sold through CKTG and most of them can be used for numerous compounds, pastes, powders and sprays. I’ll try and briefly explain the advantages and disadvantages of each substrate. As always, these products are horses for courses and my favorite might not be yours. The macro shots used were kindly provided by Ken Schwartz, the microscope pictures were taken by me. The products are all made by Hand American, except the paper.
Perhaps the most used substrate of all. It’s fairly cheap and works well with bar compounds, powders, pastes and sprays. The grain holds the abrasive particles well and the slight cushioning is good for convex edges. If you want a pure straight V bevel, then this isn’t the substrate for you. Yes, the convexing is marginal and I for one like it, but some don’t.
Bovine leather on its own (without compounds) doesn’t really do much and isn’t an optimal finisher. If you want to finish on bare leather, I would advise horse because of the silicates in it. But more on that later.
This is my personal favorite for a number of reasons. One of them is the slightly stiffer nature of the leather. The leather isn’t as soft as bovine and doesn’t convex as much. If you do want your edge to be a bit convex, you can get away with a bit more pressure here. The second reason why I like this one better than bovine is that it can be used as a plain leather finisher.
Its feedback is better and the leather has more silicates that act as a compound on its own. This isn’t like CBN, or another compound that removes scratches. It blends the scratches of the finest compounds together making the edge slicker.
This is the back of Hand American horse leather:
How this leather is processed is explained on the webpage of this product at CKTG. In short, they basically cut the top layer of the leather to expose the rougher layer underneath. Think of the layer as a cat’s tongue. Rough to the touch and slightly bumpy. This offers some advantages on its own. The grabby little “fingers” are excellent for deburring and give great feedback during deburring. I prefer this leather with sprays and more specifically sprays up to 0.25µ. The leather holds these sprays very well, and buries them into the grain. This will lead to a more polished edge and will cause the particles to not cut as deeply as on another substrate.
This a fairly recent substrate. Keith de’Grau started with this substrate and it’s become one of the most popular substrates around. And rightfully so! The slight velvety feel of Keith’s balsa holds semi pastes perfectly and the grain of the wood will hold sprays as good as any other substrate. It’s the perfect substrate for people that are looking for a precise crisp V-bevel. It has almost no compression so it approximates a stone’s hardness. A 30k Shapton is hardly inexpensive, but a 30k balsa blank is pretty cheap. A 0.5µ spray or paste combined with a balsa blank can get you close to the same results with some patience and some care. You can’t use edge leading strokes however.
Another good option for perfect V-bevels. When glued to glass, it acts as a stone and works well with pretty much every compound. It is however a bit fiddly because paper curls and when you remove it from the glass it tends to roll up. You can glue it to neoprene too so you can have a softer backing for convex edges if you like that. Contamination is very easy too. You really need ziplock bags for this substrate. Ever since balsa came to the show, paper is used less and isn’t discussed as much as it used to be. It’s still a good substrate and it can work wonders on both knives and razors. On its own, it works as a polisher. Newspaper has been used for a long time as a strop and the ink in the paper works as a compound. Paper used for fine fountain pens (like Clairefontaine) work very well.
There’s not much to say about this substrate as it’s more or less the same as paper. It’s flimsy, but flat. It has less of a grain though and therefore makes the compound cut deeper than paper. But when you scratch the mylar, you will scratch the finish. There is no room for error here.
One of the most used substrates for deburring and sprays. It’s best suitable for sprays, but I don’t like it for pastes or dry compounds. Also on the Edge Pro, it’s messy because of the hairs that fall off of the felt. When spraying compound on felt, you can get bumps because the liquid in the spray swells the surface. So spray once, let it dry, and then spray again.
Like split leather, it’s full of small holes that hide the compound making it smoother than some other substrates. The feedback is something you love or hate. For deburring, felt is the number one substrate and used most. CKTG has recently announced special deburring blocks made by Hand American.
Whatever substrate is your favorite, there’s a purpose for using them all. Luckily Mark stocks them all and has the highest quality available. We have Keith de’Grau to thank for that