No, they are by no means primative, but the quality of SOME of the electronic componenets leaves a lot to be desired. The capacitors, especially, are NOT of the finest quality. The later models, while better, are still not packed with the finest quality. When I replace cap's I use Nichicon or Panasonic almost exclusively - just changing the caps in certain areas makes a drastic difference.
By changing out the output transistors with units that not only have a higher current rating, but a faster turn on time and lower turn on resistance, you can not only squeeze a bit more power out of them, the performance is improved. You can literally hear the difference in the motor.
In defense of the manufacturer, they build to spec - what ever the end seller requests, and they pay for, they get. That is why there are some with Chinese made controllers and some with American made - it's all in what the order requires - that includes fit and finish - you can buy anything from a rough castings set to a very finely tuned unit - don't blame SIEG, et al, they are merely filling the orders given them.
All in all, the Asisan lathes and mills are a bargain. That being said, depending on what the distributor ordered, you need to do a bit of fit and polish to ge the unit within your own specifications and what you're willing to live with. The factories can turn out any quality and quantity ordered - if there's a problem, it's generally due to what was ordered in the first place.
Having worked on so many of the boards, and seen th evolution of them, I have great admiration for SIEG, et al, and the products they poduce. Like any thing built - someone may find a way to make it just a little bit better. Hopefully soon, Uncle Rabid will be moving along to not only repair the boards, but produce our own, plus more addons to make our little machines just a little more useful.
Jim RabidWolf
Uncle Rabid ( )
We Repair Electronic Speed Controllers
For Asian Mini Lathes and Mini Mills
"Just Crazy Enough To Get the Job Done"
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----- Original Message ----- From: "gerry waclawiak" <gerrywac@...> To: <7x12minilathe@...> Sent: Friday, April 13, 2007 6:46 AM Subject: Re: [7x12minilathe] Re: circuit board diagram I think your right with your general assessment of the small lathes, they
are built down to a budget price that people are prepared to pay as a
semi-disposable item. The big demand is not from dedicated machinists who
demand a top quality product but for something that is workmanlike and
affordable. Many of the UK importers seem to provide US made boards as
standard which might say something about the standard ones Chinese ones as
bring a weak point. The Chinese may not be at the absolute cutting edge of
technology but they are nowhere near as primitive as some people make out.
Gerry
Leeds UK
From: Michael Taglieri <miket--nyc@...>
Reply-To: 7x12minilathe@...
To: 7x12minilathe@...
Subject: Re: [7x12minilathe] Re: circuit board diagram
Date: Fri, 13 Apr 2007 01:08:32 -0500
I didn't mean to put down Chinese in general. They can do anything they
put their minds to and have their own space program now. But this
particular factory designed and constructed these lathes to sell as cheap
as possible (which is why so many of us can afford them), and they have
many out-of-the-box flaws. I can understand and largely correct the
mechanical ones, but there are also well-documented areas of
corner-cutting, cheap components, bad solder joints, etc., in the
electronics, an area I don't know much about and (more important), have
no desire to learn more about. I'd rather pay to have this area fixed
right than try to fix it myself and possibly screw up.
Mike Taglieri miket--nyc@...
Everyone has his reasons.
- Jean Renoir "The Rules of the Game"
On Thu, 12 Apr 2007 11:49:59 +0100 "Hugh" <hughlss@...>
writes:
Mike,
Don't be offended, but I'm going to pick-up on what you said about
the Chinese. If there's one nation of people on this earth that will
give the customer what he wants, it's the Chinese. The average
worker lacks the skills maybe, and, of course, we want their
low-cost goods - but it's not the same thing as not caring about
what customers want. Tell them and they will fix it. I should know -
I import container loads of machine tools and they bend over
backwards to put things right whenever there's a problem.
Hugh
----- Original Message -----
From: Michael Taglieri
To: 7x12minilathe@...
Sent: Thursday, April 12, 2007 9:17 AM
Subject: Re: [7x12minilathe] Re: circuit board diagram
I'm beginning to think boosting Rabid's business isn't such a bad
idea.
Uncle Rabid, how much would you charge to take my controller, beef
up all
the crap circuit-board parts and tweak the pots for maximum safe
torque
and minimum safe speed, i.e, the way the Chinese would have done
if they
gave a shit? (And do you need just the controller box, or my
motor
also?)
I'm normally an extremely do-it-yourself kind of guy, but the more
I read
here about adjusting your controller at home, the less sure I am
of doing
it right without frying something. I'd rather let someone do it
who
knows how and stick to the machining that I'm good at.
Mike Taglieri miket--nyc@...
Everyone has his reasons.
- Jean Renoir "The Rules of the Game"
On Mon, 02 Apr 2007 12:26:17 -0000 "born4something"
<ajs@...> writes:
> Hi Ian,
>
> I'd be talking more to Uncle Rabid before looking to buy a new
> board. He's the local oracle and repairs them for a living. He's
> strangely generous with his advice around here given that he
could
> just play his cards close and boost his business. I think he
> actually likes being helpful! If he can't talk you through he'll
fix
>
> it for you for a pretty reasonable fee anyway.
>
> The other reason for running things past Uncle is that he deals
with
>
> most (all?) the variants on these controllers. Most of us only
> experience one or two of them. Some are FET based and others
SCR.
> Some use relays and others don't. Mine has no relays but those
5-pin
>
> blocks are sounding like 24V coil relays. Two for the coil and
three
>
> for the changeover contact set.
>
> John
>
>
> --- In 7x12minilathe@..., Ian Fletcher
> <ian.fletcher@...> wrote:
> >
> > Hi John, thanks for the warning. I was unable to get a reading
off
>
> the second resistor so have ordered two. Visually I cannot find
any
>
> damage to the board or components apart from what looks like
> mechanical damage to one of the two square yellow blocks marked
> HR54H-S-DC24V which seem to have 5 legs, which I take to be
voltage
>
> convertors? As you can see although capable of soldering and
> unsoldering small components I am not always able to identify
what
> they are!! If I do need to bite the bullet and buy a new board
are
> they all the same from different manufacturers? I know Clarke
lathes
>
> are more expensive that others and wondered if the circuit board
> would be cheaper from other makers. Thanks Ian
> > -----Original Message-----
> > >From: born4something <ajs@...>
> > >Date: Sun Apr 01 08:02:37 GMT 2007
> > >To: 7x12minilathe@...
> > >Subject: [7x12minilathe] Re: circuit board diagram
> >
> > > Hi Ian,
> > Just a thought. Might not be what you want to hear. If only
one
> > > resistor is burnt out and they are in parallel as a 0.33 ohm
for
>
> > > current sensing then the machine should run, but overload
sense
>
> at
> > > half load. So either BOTH resistors have failed or there is
> > > something else failed too.
> > > John
> > > --- In 7x12minilathe@..., Ian Fletcher
> > > <ian.fletcher@> wrote:
> > > >
> > > > Thanks for advice, resistors ordered at cost of ???,??1 so
if
> that is
> > > all that is wrong I shall have saved ???,??84 !! Thanks for
your
> > > interest and support. Ian
> > > > -----Original Message-----
> > > > >From: born4something <ajs@>
> > > > >Date: Fri Mar 30 08:07:03 GMT 2007
> > > > >To: 7x12minilathe@...
> > > > >Subject: [7x12minilathe] Re: circuit board diagram
> > > >
> > > > > Hi Ian,
> > > > > 66 ohms sounds a bit high. You may have tricked people
with
>
> that
> > > > > space between the R and 66. Electronics types often use
the
>
> > > prefix
> > > > > as a decimal point (like 1k2 means 1.2k-ohms) and when
there
>
> is
> > > no
> > > > > prefix they just insert the base symbol, R. So R66 is
likely
>
> > > 0.66
> > > > > ohms. It's a convenient notation and avoids using those
> little
> > > dots
> > > > > that don't print clearly and are often multiplied when
> > > photocopying
> > > > > stuff!
> > > > > Check the other resistor. If it is 0.66 ohms I'd expect
> quite a
> > > > > reasonable reading in circuit without even unsoldering
it as
>
> the
> > > > > surrounding components are unlikely to be anywhere near
as
> low
> > > as
> > > > > that. If they are, it's likely a failed FET or triac,
> depending
> > > on
> > > > > your model.
> > > > > John
> > > > > --- In 7x12minilathe@..., andrew franks
> <andyf1108@>
> > > > > wrote:
> > > > > >
> > > > > > Looks as though it might be: 5W = 5 watts, R66 = 66
ohm.
> Not
> > > sure
> > > > > about the J, though - could represent a tolerance (as in
> plus or
> > > > > minus a certain percentage from the marked resistance
> value).
> > > > > However, 66 ohms isn't a standard "preffered" value - 68
> ohms
> > > is,
> > > > > though. Can you unsolder its twin, if it has identical
> markings,
> > > and
> > > > > check it? If it is 66 ohms, you may have to use a couple
of
>
> 33
> > > ohm
> > > > > ones, and connect them in series (though if you use 68
ohms,
>
> > > it's
> > > > > probably close enough).
> > > > > > As to wattage, if you can't get 5 watts from Maplin or
> > > > > somewhere, get the next size up.
> > > > > > I wonder what made it burn out, though? Hopefully, it
> was
> > > > > something simple like a short circuit caused by swarf.
> > > > > > Andy
> > > > > > ftr1d <ian.fletcher@> wrote:
> > > > > > Hi, I have just purchased a 240 volt Clarke 300m
>
> > > with a
> > > > > dead circuit
> > > > > > board. A new board will cost ???,??85 so I am looking to
> repair
> > > it. The
> > > > > only
> > > > > > fault I can see is a blown ceramic block, one of a
pair,
> which
> > > is
> > > > > > marked 5WR 66J and is in R1 position on the board. I
> assume it
> > > is
> > > > > a
> > > > > > creamic resistor? Does anyone have a circuit diagram
or
> can
> > > give
> > > > > me the
> > > > > > specification of the part. Thanks Ian
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > ---------------------------------
> > > > > > New Yahoo! Mail is the ultimate force in competitive
> > > emailing.
> > > > > Find out more at the Yahoo! Mail Championships. Plus:
play
> games
> > > and
> > > > > win prizes.
> > > > > >
> > > > > >
> > > >
> > > >
> >
> >
>
>
>
>
> Be sure to check out for small
> mills and lathes.
> Yahoo! Groups Links
>
>
>
>
>
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11/04/2007 17:14
Be sure to check out for small
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