Milling bit speed
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Milling bit speed
I have a tube that needs to be milled on the side. I have a small hole already drilled ( 5/32") and I need to make the outer end of the hole 1/4 in. about half way down the smaller hole.
I want to have a flat step inside the hole to fit a plastic 1/4 in. tube. I do not want the tube to go all the way the way through. As I remember the milling machines from high school they always seemed to run slow.
So I have the 1/4 in milling bit chucked in my drill press and want to enlargene the hole to about 1/2 way down the smaller hole already there so I can can have a flat rigde for the 1/4" tube to fit to so it doesn't go all the way through.
Anyone know if what speed the milling machine bit should be run at ?
I want to have a flat step inside the hole to fit a plastic 1/4 in. tube. I do not want the tube to go all the way the way through. As I remember the milling machines from high school they always seemed to run slow.
So I have the 1/4 in milling bit chucked in my drill press and want to enlargene the hole to about 1/2 way down the smaller hole already there so I can can have a flat rigde for the 1/4" tube to fit to so it doesn't go all the way through.
Anyone know if what speed the milling machine bit should be run at ?
Race Director
Joined: Apr 2011
Posts: 11,183
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From: North of Toronto - Ontario
A lot on unknowns here.
Lets say the material is normal cr-steel, something like 1020, lets say it's a 4 flute endmill, HSS.
A conservative rpm would be 1475-1550 on a mill. Since your on a drill-press, try about 1000-1200. Doesn't sound like much of a cut and the center is already gone
If it's a medium carbon steel (1045 ish) drop your speed down to 750 or so
If your not sure, start low and make sure it's actually cutting chips
HIH
Mooser
Lets say the material is normal cr-steel, something like 1020, lets say it's a 4 flute endmill, HSS.
A conservative rpm would be 1475-1550 on a mill. Since your on a drill-press, try about 1000-1200. Doesn't sound like much of a cut and the center is already gone
If it's a medium carbon steel (1045 ish) drop your speed down to 750 or so
If your not sure, start low and make sure it's actually cutting chips
HIH
Mooser
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Joined: Mar 2007
Posts: 3,652
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From: Bridgewater nj
A lot on unknowns here.
Lets say the material is normal cr-steel, something like 1020, lets say it's a 4 flute endmill, HSS.
A conservative rpm would be 1475-1550 on a mill. Since your on a drill-press, try about 1000-1200. Doesn't sound like much of a cut and the center is already gone
If it's a medium carbon steel (1045 ish) drop your speed down to 750 or so
If your not sure, start low and make sure it's actually cutting chips
HIH
Mooser
Lets say the material is normal cr-steel, something like 1020, lets say it's a 4 flute endmill, HSS.
A conservative rpm would be 1475-1550 on a mill. Since your on a drill-press, try about 1000-1200. Doesn't sound like much of a cut and the center is already gone
If it's a medium carbon steel (1045 ish) drop your speed down to 750 or so
If your not sure, start low and make sure it's actually cutting chips
HIH
Mooser
you can't go wrong by setting it on the slow speed as long as its not chattering.
Drifting
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From: Tallmadge Ohio
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Oldtimer
I would not use a end mill in a drill press. You are going to have problems. Use a 1/4" drill and drill to depth then if you want a flat in the bottom of that hole grind the bottom of the drill to look like the bottom of the end mill and square up the bottom of the 1/4" hole with the flat bottom drill.
Le Mans Master
Joined: Oct 2000
Posts: 8,897
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From: Santa Ana CA
Here you go. And as mentioned, you really shouldn't use a chuck for an end mill that big.
http://blog.cnccookbook.com/2010/09/...part-1-theory/
http://blog.cnccookbook.com/2010/09/...rt-2-practice/
http://blog.cnccookbook.com/2010/09/...part-1-theory/
http://blog.cnccookbook.com/2010/09/...rt-2-practice/
Thread Starter
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I'm going in 1/8 in. or so into mild steel, I think it will work, can't seem to find any flat bottom drills. I don't want to order one I know they are around, I want to do this tomorrow and only paid $4 for the bit.
Thread Starter
Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I would not use a end mill in a drill press. You are going to have problems. Use a 1/4" drill and drill to depth then if you want a flat in the bottom of that hole grind the bottom of the drill to look like the bottom of the end mill and square up the bottom of the 1/4" hole with the flat bottom drill.
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Race Director
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From: North of Toronto - Ontario
Just go slow (try 750) and feed slow and watch for chips rather than rubbing or dust.
The center is cleared away and your hardly going to cut anything on that depth anyway.
The corners will likely chip as soon as the cutter touches but it'll get through a couple of hole.
Mooser
The center is cleared away and your hardly going to cut anything on that depth anyway.
The corners will likely chip as soon as the cutter touches but it'll get through a couple of hole.
Mooser
