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hitachi230
13th January 2008, 08:30 PM
Hello everyone
I'm thinking of getting one of the Hafco lathes in the $2-3000 range for hobby work. What are the pro's and con' of belt drive vs geared head?I've read that belt drive is much quieter. Does it have any other advantages? Are they more reliable/maintainance friendly without the need for gears, gearbox's to fill and leak oil? Any feedback would be greatly appreciated.

Thanks

Brian

Wood Butcher
13th January 2008, 08:41 PM
One of the reasons I like belt drives especially for school, is that you can set the tension on the belt so it acts like a sort of slip clutch. If a too heavy a cut is tried to be taken the belt will just slip, instead of having a potential cutting tip shatter. Also they are quieter, which I prefer. However sometimes you can't get quite the same range of speeds as some gear drive, but I don't think that is a major problem.

malb
14th January 2008, 05:42 PM
Would depend on the size of machine and work. For a given work material, tool material and cutting method, there is an optimum cutting speed. For large diameter work pieces, this implies slower spindle speeds and vice versa.

Hobby priced belt drives may have trouble transmitting torque at low speed, and may lack decent low speed capacity. The are frequently limited to 6 speeds (3 direct belt drive to motor and via an idler gear). Beware of Asian units with a cog belt drive to the idler set and a V belt drive from the idler to the spindle, as the V belts seem to be sized for the torque of direct drive rather than the drive via they idler set, which has substantial torque multiplication from the idler reduction set. A positive belt tensioning arrangement is essential for regular speed changing. Make sure that the unit uses a standard belt section so that you can replace the belt with a quality one when it does start to slip.

On the other hand geared heads should not have torque problems, but often do not have a great range of high speeds for small work unless you are looking to a toolroom lathe.

As mentioned previously, belt drives tend to be quieter than gear heads, provided that the belt does not have wire joiners (flat belts) or slip (V belts).

hux
16th January 2008, 10:19 PM
It's heaps quicker to change speeds on a gear head. The gear head will undoubtably hold it value better and sell quicker.

Both will cut steel as accurately if they are built to the same standard.

Interestingly a mate has a 14x40 gearhead as does his son. One is a Taiwanese one is a mainland chinese. The taiwan build is heaps quieter.
My belt drive is quiet for a machine although my belt drive mill is quieter.