11-12-2011, 06:07 PM
A very interesting and well illustrated thread Colin!
As usual, once you embark on another new project and 'get the bit between your teeth' there's no holding you back!
What you have in mind is very similar to the Robert Sorby 'Pro-Edge' sharpening system which uses a range of belts which start at £3.00 each at the lower end, and at the top end, a diamond belt costing £125.00! The problem with normal grindstones (as opposed to specialist purposedesigned ones) is that they run at such high speeds as compared to a belt sander, though once the correct grind has been made on woodturning tools, provided a sharpening jig is used, the tool only needs the slightest touch to put the edge back on it. Chisels for woodcarving and cabinet making of course a diffent matter and must be honed to a razor sharp keen edge, whereas woodturning tools benefit from having a burr.
You're oh so right about how easy it is to take too much off metal or wood when turning due to the material coming off 'both sides' as it were! Your 'interference fit' of the bearings in the rollers is a good example of the degree of precision often called for. I have a friend who runs a light engineering part time business from his home and has an impressive array of equipment, one of which originated at a munitions factory in WW2 when unskilled women went into factories. To help them overcome errors when turning, the measurements on the toolpost are doubled, so that 0.005" is shown as 0.01", showing the amount that will be taken off the diameter of a turned item.
I think that for novice turners such as myself, the main issue is selecting the correct tooling for the job in hand. Some materials turn much easier than others. One useful tip that Colin gave me was in making shims for packing the tool up on the toolpost to centre height. Simple - no need to buy shims - just cut strips off a baked bean tin, beer can or whatever!
As usual, once you embark on another new project and 'get the bit between your teeth' there's no holding you back!
What you have in mind is very similar to the Robert Sorby 'Pro-Edge' sharpening system which uses a range of belts which start at £3.00 each at the lower end, and at the top end, a diamond belt costing £125.00! The problem with normal grindstones (as opposed to specialist purposedesigned ones) is that they run at such high speeds as compared to a belt sander, though once the correct grind has been made on woodturning tools, provided a sharpening jig is used, the tool only needs the slightest touch to put the edge back on it. Chisels for woodcarving and cabinet making of course a diffent matter and must be honed to a razor sharp keen edge, whereas woodturning tools benefit from having a burr.
You're oh so right about how easy it is to take too much off metal or wood when turning due to the material coming off 'both sides' as it were! Your 'interference fit' of the bearings in the rollers is a good example of the degree of precision often called for. I have a friend who runs a light engineering part time business from his home and has an impressive array of equipment, one of which originated at a munitions factory in WW2 when unskilled women went into factories. To help them overcome errors when turning, the measurements on the toolpost are doubled, so that 0.005" is shown as 0.01", showing the amount that will be taken off the diameter of a turned item.
I think that for novice turners such as myself, the main issue is selecting the correct tooling for the job in hand. Some materials turn much easier than others. One useful tip that Colin gave me was in making shims for packing the tool up on the toolpost to centre height. Simple - no need to buy shims - just cut strips off a baked bean tin, beer can or whatever!
Regards, David.
BVWS Member.
G-QRP Club Member 1339.
'I'm in my own little world, but I'm happy, and they know me here'
BVWS Member.
G-QRP Club Member 1339.
'I'm in my own little world, but I'm happy, and they know me here'
