I sharpened my 914A blades this weekend. They took alot of abuse last year from rocks, etc. I've been wondering how much they cost to replace. I figured they weren't too cheap!
I told my dealer to take my blades off and have them sharpened. He told me to just put new ones on as it would be cheaper to buy new?? Well he sold me a set for around $18.00. I decided I would still probably have the other set sharpened by a company and this way I would have two sets and just can replace them anytime I want.
Many folks use a 4 to 4-1/2" hand grinder. It has plenty of power and speed, and it you want, you can easily take the sharpening operation outdoors. You could pay up to $90 for one, but even the $20 grinders of this sort seem to have all that you need.