- Joined
- Jul 26, 2011
- Messages
- 4,142
If you MUST use a lathe chuck to hold an end mill (not a great idea),wrap the end mill's shank with a SINGLE layer of brown paper bag(has no clay in it) allow the ends of the paper to meet between two of the jaws. Paper holds like crazy.
I also use clay less paper to hold slippery metals like brass or aluminum in my smooth jawed milling vise. It never,never slips(if decently tightened,of course). If in doubt if your paper has clay in it,just save brown paper bag paper which is NOT shiny. Some smaller bags seem to have waxy surfaces.
NEVER,EVER use a brass bushing to hold end mills. MANY years ago,I made a brass bushing. The end mill would suck out of that bushing no matter how tight I got the draw bar. Only use steel,and never let clamping surfaces get oil on them.
To make sure a drill bit is straight when buying at the local store,put it on the counter,and run it back and forth under your finger,looking for wobble as you do so. Even the best brands can have some curve to them.
I have heard it said that the Chinese drill sets might have only the even fractional sizes hardened(like 1/8,3/16,etc.) They think the average user just uses the common sizes.
To make your drill start straight(without starting with a wobble) in your lathe when drilling WITHOUT a center drilled hole(which is best),place the blunt end of a lathe bit against the drill bit. As the drill meets the metal,if it wobbles any,carefully advance the lathe bit until it stops wobbling. The bit will then start to drill the hole without making little circles. This is a quickie way to accurately drill a hole without center drilling.
Three flute end mills are a PITA to measure the dia.,unless you have the right kind of mike. 2 or 4 are easier to check,if you are using a resharpened mill(or,perhaps even some new ones of dubious origin).
More will be posted other times.
I also use clay less paper to hold slippery metals like brass or aluminum in my smooth jawed milling vise. It never,never slips(if decently tightened,of course). If in doubt if your paper has clay in it,just save brown paper bag paper which is NOT shiny. Some smaller bags seem to have waxy surfaces.
NEVER,EVER use a brass bushing to hold end mills. MANY years ago,I made a brass bushing. The end mill would suck out of that bushing no matter how tight I got the draw bar. Only use steel,and never let clamping surfaces get oil on them.
To make sure a drill bit is straight when buying at the local store,put it on the counter,and run it back and forth under your finger,looking for wobble as you do so. Even the best brands can have some curve to them.
I have heard it said that the Chinese drill sets might have only the even fractional sizes hardened(like 1/8,3/16,etc.) They think the average user just uses the common sizes.
To make your drill start straight(without starting with a wobble) in your lathe when drilling WITHOUT a center drilled hole(which is best),place the blunt end of a lathe bit against the drill bit. As the drill meets the metal,if it wobbles any,carefully advance the lathe bit until it stops wobbling. The bit will then start to drill the hole without making little circles. This is a quickie way to accurately drill a hole without center drilling.
Three flute end mills are a PITA to measure the dia.,unless you have the right kind of mike. 2 or 4 are easier to check,if you are using a resharpened mill(or,perhaps even some new ones of dubious origin).
More will be posted other times.
