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Two live centers? - Scouter - 10-09-2020
Looking at making a lathe using one of a number of plans I've found. Question: is there a reason a lathe shouldn't have two live centers instead of a live and dead ones?
RE: Two live centers? - Grey Mountain - 10-09-2020
If you are talking about a live center in the tail stock and another in the heard stock, the workpiece would not turn.
GM
RE: Two live centers? - MichaelMouse - 10-09-2020
(10-09-2020, 04:11 AM)Scouter Wrote: Looking at making a lathe using one of a number of plans I've found. Question: is there a reason a lathe shouldn't have two live centers instead of a live and dead ones?
Some production work I've seen referenced uses two cup centers -no bearings- and friction turns the piece. I use a double spur center, not a four-spur, and a saw kerf which allows almost as easy workpiece mount-dismount.
RE: Two live centers? - Scouter - 10-09-2020
(10-09-2020, 05:26 AM)Grey Mountain Wrote: If you are talking about a live center in the tail stock and another in the heard stock, the workpiece would not turn.
GM
I don't see why not. The one center would be attached to the motor, the other would sit inside a flange bearing, why wouldn't it turn?
RE: Two live centers? - SceneryMaker - 10-09-2020
(10-09-2020, 06:09 AM)Scouter Wrote: I don't see why not. The one center would be attached to the motor, the other would sit inside a flange bearing, why wouldn't it turn?
A live center, by definition, has a bearing between the point at the front and its taper at the back. This lets the point turn relative to the part it's plugged into, typically the tailstock.
A dead center is all one piece so that it turns with the part it's plugged into, typically the rotating headstock.
RE: Two live centers? - Scouter - 10-09-2020
(10-09-2020, 06:26 AM)SceneryMaker Wrote: A live center, by definition, has a bearing between the point at the front and its taper at the back. This lets the point turn relative to the part it's plugged into, typically the tailstock.
A dead center is all one piece so that it turns with the part it's plugged into, typically the rotating headstock.
Okay, I understand. Since mine will be homemade the setup would be different. One center would be chucked into a 1/3 hp drill using a forstner bit, the other side would be another forstner bit in a pillow bearing. I think this would work.
RE: Two live centers? - daddo - 10-09-2020
(10-09-2020, 07:34 AM)Scouter Wrote: Okay, I understand. Since mine will be homemade the setup would be different. One center would be chucked into a 1/3 hp drill using a forstner bit, the other side would be another forstner bit in a pillow bearing. I think this would work.
I think it's a good idea. Would be good for smaller work.
The motor/chuck bearings might handle it.
RE: Two live centers? - Scouter - 10-09-2020
(10-09-2020, 08:42 AM)daddo Wrote: I think it's a good idea. Would be good for smaller work.
The motor/chuck bearings might handle it.
This is just for a prototype test, if it works then I have a blower motor that I can attach a rheostat to for variable speed.
RE: Two live centers? - Arlin Eastman - 10-09-2020
(10-09-2020, 06:09 AM)Scouter Wrote: I don't see why not. The one center would be attached to the motor, the other would sit inside a flange bearing, why wouldn't it turn?
A live center free spins on bearings. If you have two of them then the head stock which is the drive part will allow the live center to spin but when you try to engage the wood with any tool it will stop the wood but the head stock will continue to spin.
Now the other way is a spur drive in the head stock that will not spin or have bearings in it and a live center in the tail stock will allow the wood to spin but still allow the wood to be cut.
There are on occasions where I put a straight pointed MT2 drive into the head stock and gently engage the tail stock to allow the wood to find its balance and then readjust until it finds it balance and change out the drive to a spur drive to drive the wood.
RE: Two live centers? - Arlin Eastman - 10-09-2020
(10-09-2020, 07:34 AM)Scouter Wrote: Okay, I understand. Since mine will be homemade the setup would be different. One center would be chucked into a 1/3 hp drill using a forstner bit, the other side would be another forstner bit in a pillow bearing. I think this would work.
Using a forstner bit in a head stock or tail stock will drill into the wood not hold the wood with any pressure put on them. I do not know how you can keep from doing that.