New attachment

[mike-E]

Well, if I understood your description correctly, I think a setup like that would have quite the same characteristics as my initial iteration, which I believe has several drawbacks (at least from my point of view, and how I'm using the contraption).

Some of these drawbacks would be; 1) friction and heat build up (which to an extent can be mitigated by increasing the angle you run the belt across, but at the cost of decreasing functionality), 2) more cumbersome to change from left to right grinding action, and 3) running belt over a corner without rollers/bearings will increase the risk of breaking belts.

After further testing I find that the new design addresses all these drawbacks and I'm still happy with it. Next step is to tidy it up and get rid of the all thread rod, which I only used for prototyping. The protruding nuts will need to be flush so they don't interfere with the use of a work rest, for example.

On your original when you were grinding was the handle pointed toward the motor? If so did you have to walk around opposite sides of the grinder to use it, or did you flip the knife edge down? Maybe I'm not understanding how you were using it. Was heat build up and wear horrible on the corners? What about at slow speeds?

 

[Stromberg Knives]

On your original when you were grinding was the handle pointed toward the motor? If so did you have to walk around opposite sides of the grinder to use it, or did you flip the knife edge down? Maybe I'm not understanding how you were using it. Was heat build up and wear horrible on the corners? What about at slow speeds?

Actually, I did in fact incorporate the feature to grind both left and right in the original version.

The attachment pivots on the tooling arm. There are to fixed settings, so that you don't have to grind edge down. But still, the inherited heat build up from this design makes it a less trustworthy solution. Even at slow speed I found myself looking for scorched metal and waiting for a belt slap to occur. Even at these angles (about 45 deg) the 3 hp motor struggled to get it going, it felt like an unnatural configuration on the constant edge of failure.

If you are interested in building one, I would recommend you to use the new design.

 

[Stacy E. Apelt - Bladesmith]

Dang! I really like that idea. What is the platen made from?

 

[Stromberg Knives]

Dang! I really like that idea. What is the platen made from?

Thanks! The platen is refurbished from the old version, nothing spectacular. I use hardened O1. Which I believe you helped me dial in the HT recipe for a long time ago. Haha.

I'm happy with it, O1 is easy to find in any size or shape. And I throw it on the SGA once in a while and it's back to pretty much full flat (flat enough for me, at least).

The refurbish part is also the reason it's got a couple of extra holes. But I plan on tidying up the attachment now that I've moved past the proof of concept stage.