Actually, this statement below isn't entirely true. I
bought two DSI punches (one with a reader) on eBay for
$40.00 shipped for the punch in not very good
condition and about $100 for the punch/reader in
better condition. (see
sloboyko.home.mindspring.com/ptfun.htm). I think you
can get a bargain if you hold out for a less than
perfect one or find one that Western Numeric might not
find attractive (like a Remex). The practically unused
GE Decitek reader on my web page I found on eBay (in a
beautiful flight case, and this unit alone is still
sold NEW for >1700.00), I got for $20 probably because
the seller misclassified it not knowing what it was.
No docs and 24 DIP switches but I have it working well
enough. The manual is still available - for more than
3 times what I paid for the unit!
The data I/O reader on that page (~$50) took some
goofing around with to power, and figuring out mystery
serial speed/bits/parity, but it was very well worth
it! It's unusual in that it can read 5-8 level tape by
rotating a guide in the read head.
I also have dealt with Western Numeric and their
prices are high on parts and stuff, because they can
be. I needed belts for the unit I got in bad
condition. After some looking around on the Internet I
found super Kevlar belts for about 20% of what he
wanted for 'em. But, I'm a hobbyist, and if you needed
it for business, you can't guess or waste time. There
service is very good.
If you can do this kind of serious machining, great;
personally, I'd hold out for an "unknown" mechanism
with an "unknown" interface or a broken one on eBay. I
think coming up with the mech is 90% of the work, and
keep in mind, it's got to be pretty rugged (I think
the DSI is constructed mostly of tool steel). It's
mechanism is stepper controlled, but I had to goof
around with the belt tension quite a bit (cogged type
belts) to get the rows of holes spaced just right and
evenly feeding. The mech is powered by an AC
syncronous motor that doubles as a fan. Apparently, a
clutch helps to move the paper while the stepper does
the fine movement. It's got solenoids and levers that
actually do the punch pin movement. It is powered by a
big 24/5 volt linear power supply.
The DSI mechanism looks pretty rugged; the punch I
have in better condition has sharper dies than the
other, I think (count the number of holes, and then
consider that these punches can do mylar, and, well,
you can see why the dies need resharpening). I haven't
taken mine apart yet, and Western wants $50 just for
the manual. This is why you might think I'm a pig to
have TWO punches, but I'm afraid of how much one would
cost to fix if it broke because it's doubtful that I
could repair it simply because of lack of unique parts
no longer made. The DSI's have some kind of wacky
Intersil processor running them, and good luck finding
anything on the Internet about DSI.
--- Bill Richman <bill_r_at_inetnebr.com> wrote:
> On Fri, 8 Mar 2002 19:59:36 -0600 (CST), you wrote:
>
> >> Does regular paper tape normally come with the
> sprocket holes pre-punched,
> >> or does the device that punches the data holes
> also punch the sprocket
> >> holes?
> >
> >The paper tape punch also punches the sprocket
> holes.
> >
> >> I recently bought some "paper tape" from eBay,
> and it looks like
> >> the right stuff except it's totally without
> holes. I don't think I've
> >> ever seen "virgin" tape before, but I had the
> idea that the sprocket holes
> >> down the middle came with the tape. I'm kicking
> around trying to build my
> >> own tape punch, since I have been unsuccessful at
> scrounging or buying one
> >> so far.
> >
> >You have been unsuccessful for a very simple
> reason. Western Numerical
> >Controls sells new and refurbished tape readers and
> punches at absurdly
> >high prices. And because of this, they buy all the
> good punches that
> >appear on ebay. In fact, the guy who buys them, is
> the exact same guy
> >who sold you that paper tape.
> >
> >Its very difficult to compete with a bidder who
> plans to turn around and
> >resell (or attempt to resell) the paper tape
> punches for $2000.00 or
> >so that he buys for $200 - $600 on ebay.
> >
>
> Ouch. That would certainly explain it. I kept
> getting outbid by the
> same person, but I didn't put 2 and 2 together. I
> guess it's the free
> market economy at work, but it makes it tough if you
> can't justify
> paying a high price from something since it's just
> to play with.
> <sigh>
>
> >> I picked up some stainless steel flat and some
> rod of the
> >> appropriate diameter for the holes today, along
> with some solenoids for
> >> actuating said rods. I'm thinking of machining
> the stainless to make my
> >> own punch, but the lack of sprocket holes on the
> new tape has me confused.
> >> Do I need to add another solenoid and pin to
> punch a smaller hole for the
> >> sprocket, or did I just buy some odd-ball tape?
> >>
> >
> >Are you making some sort of manual paper tape
> punch?
> >
> Well, actually I was considering running it with a
> BASIC Stamp 2; then
> it could take either RS-232 serial input from a PC,
> or parallel TTL
> input from my Mark-8. I really have no idea how
> much force it will
> take to punch clean holes in the tape. I plan to
> machine the metal
> parts for my design and harden them, and then see
> how hard a solenoid
> has to whack the pins to get a clean cut. I picked
> up a box full of
> solenoids tonight at the Surplus Center, and I'm
> hoping they'll be
> strong enough. If so, I'll just need to put
> together some drivers so
> the BS-2 can energize them, and a stepper motor or
> something to pull
> the tape through. (If anyone can supply any details
> about how a
> commercial tape punch works, I'd be very interested
> to know. No sense
> reinventing the wheel...)
>
> -Bill Richman (bill_r_at_inetnebr.com)
> Web Page: http://incolor.inetnebr.com/bill_r
> Home of the COSMAC Elf Microcomputer
> Simulator, Fun with
> Molten Metal, Orphaned Robots, and
> Technological Oddities.
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Received on Sat Mar 09 2002 - 00:07:05 GMT