Re: anybody have info on laguna lathe?

Ralph E Lindberg wrote:

The use of a DC motor is enough to tell me I don't think I would be
interested. They have torque issues at low RPMs (Plus I think Laguna is
consistently over priced)


I'm not an EE but here goes

I used to make jewelry and a flex shaft with a range of handpieces.
I started out with an AC Foredom motor with a carbon pile foot pedal
for varying speed. At low speeds it had almost no torque. I
switched
the foot pedal speed control to a wire coil rheostat hoping to gain
low speed torque. Didn't work as far as I could tell. So when
Foredom came out with a DC motor and rectifier foot pedal I tried
again. That did the trick. Good torque at about 100 rpms, not
noticably different from full rpm torque.

Second anecdotal evidence - Fisher Paykel washing machine uses a
DC step motor attached directly to the wash tub - as opposed to
the old transmission system of the AC motor approach. The FP
unit has a variable spin speed. A full load of damp clothes requires
a fair amount of torque to start to spin that weight - and the FP
has no problem doing it - with no clunking tranny - and spinds up
to pushing 1000 rpms. Clothes come out nearly dry BTW.

Third anecdotal evidence - electric cars - their motors are DC.
Accelleration requires low end torque initially - and there's a
0-60 mph in under 6 seconds out there now.

So I'm not sure what DC speed control you've got experience
with but my experience hasn't been what you mentioned.

Re: Laguna Tools prices - their main income is from professional
production machines. Their hobbyist stuff is the low end of their
product line. BUT - when they put their name on a machine it's
one they spec'ed or an available one that meets their specs -
which are typically pretty high. They want to sell a machine
to a customer and only hear from the customer when they
want to buy additional machines or upgrade their machines.

charlie b
.

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