I have been using a nice green painted Asian CH-250A 1995 model 7x10
minilathe made in Taiwan for 4 years or so. No controller problems at
all so far. The controller uses SCR's (5 of them!) and the low speed
cannot be adjusted with the internal pots to less than 150 RPM and
remain constant under load. I took care of that with a 2.5 times
speed reduction between the motor and the lathe. It makes threading a
bit safer!
Some nice folks recently presented me with a neat blue Homier 7x12
which has a controller with a low speed of 0 RPM. I like that much
better. It uses the famous mosfets (we shall see). There are some
other differences though which are not obvious at first glance:
1. The compound slide (bottom slide)the one which rotates, on my
ch250 is aluminum as is the cross slide ( the part which moves in and
out) on the saddle. The Homier counterparts are both steel.
2.The height from the tool holder mounting surface to the spindle
center on the Homier lathe is 3/32" (as measured using a 6 inch steel
scale) less than the ch250 model. Can't swap tool holders without
readjusting!. The tool holder I use (Carlton) is similar to the Mert
one except for the supporting post and will not fit the Homier at
all. I made a center support to fit and can use the movable tool
holders on both designs now,( still a pia).
None of the above is critical but there may be more! Richard
