Joshua Fisher
Knifemaker / Craftsman / Service Provider
- Joined
- Mar 27, 2018
- Messages
- 1,501
I wanted to start a post to talk about vsm abrasives a bit and the belts I’ve been using a lot in my shop and hopefully someone finds this useful. I think a lot of us have tried vsm and most people I’ve spoke with feel they are some of the best value belts on the market, granted everyone will have a different grinding style so I always recommend trying multiple brands of belts or lines within the same brand and find what works well for you. Well here are the two belts that have been working really well for me and why I use them. I start off with 36 or 50 grit 880 line ceramic belts, these seem to cut really cool and work well in medium to light pressure applications. I do 90% of the work with one of these two belts, I start by using a worn belt to break my corners at about a 30-40 degree angle to a center line then start grinding in my bevel. Majority of my knives I hollow grind and the way I grind my bevels is after my edge centerline is established I start grinding a new facet or hollow right behind that initial angle, this is important especially for thin kitchen knives as the edge can heat up fast when trying to remove the bulk of material so I like to leave a little bit of meat before the edge and this acts as a heat sink in a way and helps prevent overheating the thin edge. For hollow grinds I mark my bevel height on both sides and will hog out material all the way up to that line but still leaving a bit of material to blend in and thin out the edge, now here is where I’ve found I can really effect my abrasive life, I do all the hogging at full speed with medium pressure which keeps the belt cutting well but if I try to blend into the edge especially with stainless steels that are heat sensitive you can quickly overheat the edge and so if I keep using the hogging belt I’ll likely burn the edge or end up going through quite a few belts to always have a fresh belt (means I may only get 1-2 chef knives from a belt then I change out to a new one) this can be quite expensive and I’ve found even slowing down with the hogging belt doesn’t necessarily help completely as the belt then wants to glaze or clog. So here’s where the second vsm belt comes in I use a 80 grit XK733X line belt it looks like these belts were actually designed for materials like aluminum with a special coating to keep the grinding area cool without using greases. I switch to this belt to blend the final grind in and thin out the edge, this works really well even on stainless steels going down to .005-.007 thou without getting the edge hot, I run these at 30% speed and they still remove a good amount of material quickly. Using this system I can hollow grind a hardened 8” chef knife in under 20 minutes from full thickness. By using both lines of belts for different stages I can get 5-6 chef knives out of my first ceramic belt instead of 1-2 and I can get almost the same number out of the 80 grit belt, the guys at Popsknifesupply have been calling the XK733X belts white lightning, they have also found the white color of the belt makes it easier to see what you are doing acting like a bright backdrop. Again I hope someone find this information useful since the topic of belts comes up frequently. 
