Metal Lathe Low speed?

Refering to the Asian 7X12 lathes, some have a low speed of zero and others begin at 100+ rpm.
Is this a significant consideration regarding a purchasing decision?

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No. Just marketing hype. Every lathe has a low speed of zero, by just not engaging the drive. The statement is about as meaningful as saying a car has a low speed of zero. So while this is not a significant consideration, I would keep away from a comapny whose brochures are so misleading and confusing to a newbie.
Boris
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Boris Beizer Ph.D. Seminars and Consulting
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not
consideration,
I would add that the legitimate lowest speed and the highest speed are important considerations. The smaller the lathe the more important the higher speed and the less important the lowest speed. It's all about getting the surface speed correct for the work you're doing. The smaller the diameter of the work the lower the surface speed for a given rpm. Let's take some typical cutting speeds in feet-per-minute for several materials you're likely to turn:
steel 150 brass 300 Aluminum 500 wood 1000
Now consider various diameters of what you are about to turn: 1/4", 1/2", 1", 3", 7" . You can looks these up in a handbook, such as the Machinery handbook with the following results:
1/4 1/2" 1" 3" 7" steel 2140 1224 535 185 76 brass 4585 2290 1450 380 180 aluminum 7639 3440 1720 640 270 wood 15,000 6880 3440 1270 544
Now you are very unlikely to turn something 7" in diameter on a 7" lathe. It could be a bowl, or a plate, but not a shaft because there isn't enough room over the cross slide to turn something that big. Also, something that diameter will be pushing beyond the power limits of the lathe, its rigidity, not to mention the size chucks you have. Practically speaking, a 3" diameter is a working maximum for typical work on a 7" lathe. So the lowest speed you're likely to use (except for cut off tools and threading) will be about 185 to 200 rpm. Note however, the high speeds you're likely to use - most lathes won't go that high -- even wood working lathes. The lowest speed is important for using a cut-off tool and for threading. By and large, there you want to go as slow as possible. Certainly while you're learning. It's not enough to have a high high speed-- it has to be a good high speed, meaning the bearings are good and there's no wobble in the spindle at high speeds. Okay, that's lesson 001 in the selection of a lathe. A while back, someone in this newsgroup posted an article entitled "Advice on buying a clunker." or something like that. As I recall, that was an excellent introduction to get you to level 002. Suggest you let the group know what you intend to do with the lathe, which ones you have in mind, and get a sharper answer to your question.
Boris
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I don't think any of the currently shipping models have the older motor controller. I just got one from Homier (who in the past shipped a model with a different controller) and it will turn very very slowly.
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