I see you are trying to split the point by hand to remove the wide chisel edge after the 4 facet grinding........why bother, I have sharpened small drills of 2 mm diam by hand using a Wishbone type drill sharpener and never split the point. Why split the point when you are dimpling the work piece initially before drilling the hole........splitting the point to remove or reduce the chisel edge is just to make drilling easier with less pressure...........on larger drills it is easier and works better to allow less downward pressure on the drill bit. Drilling is not an accurate hole sizing operation, it is to remove metal for either clearance or for pre tapping.....accuracy of the hole size is achieved by accurate grinding of the drill point to ensure it revolves evenly without side deflection..........the point of the drill, even with a chisel edge present, will ensure the drill pivots about a centre line and depending on the accuracy of the centrality of the point when being ground. It is also possible to grind a drill with the drill point off centre, having unequal end face lengths, to make it drill eccentric and so making a slightly larger hole diam than the actual drill size.....for a special purpose. BTW.....I like the camera being used to magnify the work being ground. I see you are able to move the grinding wheel axially instead of using the pivot bar at the bottom that mounts the swing tool holder.....this is a feature I will use too as I am building a T/C grinder similar to the U2 or Deckel OS type.....this will be much simpler to achieve axial movement of the grinding wheel than moving the pivot bar/swing assembly. Edit........I decided to go with the axially moving pivot bar design, same as in the U2/3 types, as it is more precise and suites my purpose.
Thanks for your so detailed comments, we will keep update the machine, and we open to your advise, you may can contact me through this email: tools@qdgrinder.com
Can this machine use for sharpening the knife of overlock sewing machine
6mm ballnose can grind ?
Sure, it can grind ball nose mill of 3-16mm in diameter.
I see you are trying to split the point by hand to remove the wide chisel edge after the 4 facet grinding........why bother, I have sharpened small drills of 2 mm diam by hand using a Wishbone type drill sharpener and never split the point.
Why split the point when you are dimpling the work piece initially before drilling the hole........splitting the point to remove or reduce the chisel edge is just to make drilling easier with less pressure...........on larger drills it is easier and works better to allow less downward pressure on the drill bit.
Drilling is not an accurate hole sizing operation, it is to remove metal for either clearance or for pre tapping.....accuracy of the hole size is achieved by accurate grinding of the drill point to ensure it revolves evenly without side deflection..........the point of the drill, even with a chisel edge present, will ensure the drill pivots about a centre line and depending on the accuracy of the centrality of the point when being ground.
It is also possible to grind a drill with the drill point off centre, having unequal end face lengths, to make it drill eccentric and so making a slightly larger hole diam than the actual drill size.....for a special purpose.
BTW.....I like the camera being used to magnify the work being ground.
I see you are able to move the grinding wheel axially instead of using the pivot bar at the bottom that mounts the swing tool holder.....this is a feature I will use too as I am building a T/C grinder similar to the U2 or Deckel OS type.....this will be much simpler to achieve axial movement of the grinding wheel than moving the pivot bar/swing assembly.
Edit........I decided to go with the axially moving pivot bar design, same as in the U2/3 types, as it is more precise and suites my purpose.
Thanks for your so detailed comments, we will keep update the machine, and we open to your advise, you may can contact me through this email: tools@qdgrinder.com
Price
Hello, can you provide us with your email so that we can send you the quotation