Re: [CAD_CAM_EDM_DRO] Re: Servos and Controller boards

Hi Ballendo, thank for the encouragement
ref .......I have no idea what Nick already knows about servos........
answer is very little of use :-) but willing to learn.

Nick

----- Original Message -----
From: "ballendo" <ballendo@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Tuesday, April 13, 2004 4:04 AM
Subject: [CAD_CAM_EDM_DRO] Re: Servos and Controller boards


> Caudlet,
>
> A good reply. Let's take up the points in snips and inserts below...
>
> >In CCED, "caudlet" <info@t...> wrote:
> >I did not make that post glibly. I would be the first one to
> >recommend that building vs buying is an indivdual choice. You
> >noticed I said "I would not attempt it". I have done closed loop
> >controls with servos and spent a good many years working with
>
> I think this is partly why you don't wish to "do" what
> you've "already" done. Sort of like having to "work" at your hobby.
>
> > The newer chips are all SMT and make a hobby level design a
> >challenge for anyone.
>
> DIY-CNC is not all about the "newest" chips. In fact many of our
> solutions use age-old techniques and circuits... But even when we DO
> use the newer SMD's and SMT's, we're just continuing an electronics
> tradition, which means we have to change our techniques to match
> what's happening now. Mariss recently mentioned on his geckodrive
> forum that the "death" of 4000 series cmos seems imminent. But that
> thread also reaffirmed that we will have other choices to replace
> them. (Perhaps not as good in some ways, but time does march on) I'm
> a member of a homebrew pcb and also desktop SMD oven group. So there
> are folks exploring how to bring the new chips under a hobbyist's
> control. (And it's not as hard as some would have you believe!)
>
> > If someone posted and asked about designing and winding their own
> > stepper or servo motors what would you advise?
>
> We both know the answer to this red herring, or straw dog... Making
> motors is not ANYWHERE near making circuits. (I'm not saying circuits
> are "easy", but a circuit/pcb is DEFINITELY much more accessible to
> the average person than making a motor.)
>
> >Each person has to evaluate their skill level and decide if the
> >effort (and probable failure) to build something that can be
> >purchased for 65 bucks is worth the "learning" experience.
>
> Yes. But as I said, saving money is not the sole reason for people to
> join this hobby.
>
> > If someone is looking to dive into the guts of doing a power servo
> > design they should slide over to the OSMC (Open Source Motor
> > Control). There you can rub shoulders with guys that have already
> > tackled the problem of DIY servo controllers, brushless DC (BLDC)
> > controllers and AC servo control.
>
> I'm a member of that group. But they don't seem to be CNC directed;
> more of a battlebot stance... (And those two "servos" are not very
> closely related, IMO.) IMO, they've taken the high road and gotten
> stalled, and the low road has product, but it's not suited to CNC
> needs. The hoped-for middle ground just hasn't happened yet...
>
> >One of our responsibilities (sounds noble huh!) is to help guide the
> >new persons through the maze. Part of that is to take our
> >experience and keep people from heading off down a rough road and
> >maybe loose them as part of our community.
>
> I think it's pretty noble to actually ANSWER the question ASKED!!!
> (Or admit that we don't have an answer; and offer support so the
> person doing the asking CAN try to find an answer that may help us
> ALL...
>
> When someone asks us, "Where can I learn <more> about servos?"; I
> don;t think we are noble (or helpful) to say, "Don't bother. It's a
> tough thing to do, and Vlad over here, or JR, has already done it, so
> just buy what they've got..."
>
> Certainly we should warn that it's a potentially tough road. But we
> need to temper that with encouragement that might lead someone (whose
> skill set we really have NO idea about!) to a NEW solution.
>
> As an example, the EMC project has benefitted GREATly from the
> efforts of many; but I'd say that Ray H has had a HUGE impact. He
> didn't HAVE the necessary skills when he started (according to posts
> he made at the time). But he DID have a desire. Because that desire
> was encouraged, and "helped", he pursued a somewhat singular goal, we
> now have many additions to the EMC code and GUI...
>
> Why don't we give that same encouragement to the poster who started
> this thread? I have no idea what Nick already knows about servos, but
> He has asked us to help him "know" more. Are we going to answer his
> question??? (What can YOU tell us about high current switching
> layouts, mosfet drivers, and such so that WE DON'T have to get a T0-
> 220 in OUR forehead?!?!?)
>
> <snip>I just get the drift that the electronics design skill set is
> >not possessed by the majority of the builders.
>
> We don't need "electronics skill set" to be possessed by the
> majority. ONE interested and therefore committed individual is
> enough. Like Ray H... Or Paul C... Or Mariss... Or Jeff... Or Vlad...
> Or Art F... (The list of INDIVIDUALS who have impaced our "hobby" in
> a MAJOR way is a long one. In a very polarised discussion on this
> list a few years ago, I said that by using the RDTSC pentium
> instruction, windows CNC should be possible. And asked for a 1-8K hz
> output. ONE person, Art F, took that as a challenge, and with MUCH
> effort, and MANY LONG HOURS (and the co-efforts of hundreds, who
> followed HIS lead), we now have Mach2...
>
> What if he had listened to the naysayers, who at the time
> said, "Windows CNC is just nort possible, or worthwhile. We have good
> DOS programs which work fine. Just use them."??? (You can read these
> messages in the archive.)
>
> >Maybe we need a "star" rating system like they do on DIY TV.
> >Building your own power supply is ** while designing a closed loop
> >servo for power control is *****.
>
> You know, that's not a bad idea. But ** to one person is ***** to
> another. Use yourself for an example. Nearly any high
> current "switching" electronics is gonna be a * for you. But don't
> you have areas which are ***** that others would find to be a *?
>
> Let's try and support the INTEREST of the poster, and not just throw
> our experience at 'em... And try to answer the question(s) they've
> asked.
>
> Food for thought,
>
> Ballendo
>
>
>
>
>
>
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