5 Jan
2006
5 Jan
'06
11:29 p.m.
OK, I have had terminals shipped to me in the past and they were fine,
but I experienced a bit of damage when having a Heath Z-19 terminal
shipped to me recently. Fortunately it can be repaired, but I think
its just that I came out somewhat lucky (even more lucky would for it
to not have been damaged at all).
If you were to ship a terminal/monitor, what would be your approach?
In the case of the Z-19, I think the root cause is that only 1 of the
4 mounting screws for the tube in the case had a support bracket.
This is the only mounting post that didn't shear from the rest of the
enclosure. The other 3 posts sheared off at their base to the
enclosure. Some superglue should be able to reattach the posts to the
enclosure so that the whole thing will be "like new". So this might
be something specific to this enclosure design.
However, I'm currently looking at a Tektronix 4115 that's in Illinois
and I'm in Utah. This is an item that would be "key" for my graphics
collection (and I've not seen one offered with any great frequency; a
local supplier has them but he charges $1200 minimum for these units
as costly replacements for mission critical systems). However, I'm
really leary of shipping it that far after my experience with the
Z-19.
Comments?
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6 Jan
6 Jan
12:22 a.m.
Richard wrote:
In the case of the Z-19, I think the root cause is
that only 1 of the
4 mounting screws for the tube in the case had a support bracket.
This is the only mounting post that didn't shear from the rest of the
enclosure. The other 3 posts sheared off at their base to the
enclosure. Some superglue should be able to reattach the posts to the
enclosure so that the whole thing will be "like new". So this might
be something specific to this enclosure design.
I wouldn't use superglue. Try JB Weld, or some other 2 part epoxy, if
you can't find the JB Weld. I successfully repaired one of the mounting
posts for the power supply of an IBM PS/2 Model 80 using JB Weld.
However, I'm currently looking at a Tektronix 4115 that's in Illinois
and I'm in Utah. This is an item that would be "key" for my graphics
collection (and I've not seen one offered with any great frequency; a
local supplier has them but he charges $1200 minimum for these units
as costly replacements for mission critical systems). However, I'm
really leary of shipping it that far after my experience with the
Z-19.
Well, if the tube is only mounted on it's face then the mass of the tube
and gravity are creating a torque on the mounting posts. I have no idea
what a Textronix 4115 looks like, but could it be packed tube down?
That way the force due to gravity would be directly in line with the
mounts and wouldn't create a torque that would break them. Of course
all this is pointless if the packer can't pack worth beans. Even
further, if the box ended up being tall, it may get tipped over in
shipping therefore defeating the face down packing arrangement.
Chad Fernandez
Michigan, USA
1:17 a.m.
Disclaimer: I don't ship monitors (well, maybe one or two).
Claim: I do ship a lot of very delicate musical instruments, like tubas.
What I've learned:
Double-walled cardboard is a must. If you're shipping by truck and the
size of the item warrants it, it's even better is to build a crate (from
wood) and strap it to a pallet.
Bracing--the object must not be able to shift within its box. If an object
can shift, it will develop sufficient momentum to cause damage. Styrofoam
"peanuts" do not prevent shifting. It's far better to purchase some sheet
styrofoam insulation from a home improvement store and cut it to fit around
the object, within the box. Peanuts can be used to fill voids, but your
customer will love you if you first put them in a bag, so they don't
migrate all over the place.
If you have a particularly fragile surface, such as the bell of a tuba or
the faceplate of a monitor, invest in a cheap toy beach ball. Partially
inflate it and use it as a shock absorber--it will distribute forces far
better than anything else.
If anything can get loose (access panels, cords, etc), tape them down.
If it's a large package and you have access to passenger rail service,
consider Amtrak Express. Their rates and service can sometimes beat most
of the other common carriers--and your package will ride in a baggage car,
not be tossed off some conveyor belt used to load a plane.
---
Super glue may not be the best answer to reattaching those bosses. Try a
few drops of MEK or methyene chloride--the action on most styrene or
acrylic plastics will be that of a solvent. The cured join will be nearly
as strong as the surrounding material. Do NOT do this with transparent
plastics--it will fog them.
For whatever it's worth.
Cheers,
Chuck
7:46 p.m.
In the case of the Z-19, I think the root cause is
that only 1 of the
4 mounting screws for the tube in the case had a support bracket.
This is the only mounting post that didn't shear from the rest of the
enclosure. The other 3 posts sheared off at their base to the
enclosure. Some superglue should be able to reattach the posts to the
enclosure so that the whole thing will be "like new". So this might
be something specific to this enclosure design.
I would not use isocyano acryllic hydro-copolymerising adhesive. I've
never found it that good on plastics. The best way I've found to repair
most thermoplastiss is to get a suitable solvent (dichloromethane is
often suitable, it's sold by good model shops under the name 'Plastic
Weld'). Put the pieces together dry, then run a brush dipped in the
solvent along the joins.
Then, as I mentioned once before, strenghen it further by takening a
piece of cotton cloth, cutting it to fit over the repaired area on the
back, puting it on, brushing it over with solvent, and forcing it into
the softened plastic.
However, for something like a CRT mounting, I'd not trust that. I'd cut
off the original pillars, and smooth the inside of the case flat. Then
make new metal pillars, drill and tap them along the axis, and fix them
in place with screws from the outside. Conenct them to mains earth (or
similar), just in case something breaks down and makes the screwheads live.
No, it's not original, but then a CRT coming loose is not particularly
pleasant.
-tony
7 Jan
7 Jan
4:57 p.m.
In article <m1Ev2Dl-000Iy9C at p850ug1>,
ard at p850ug1.demon.co.uk (Tony Duell) writes:
However, for something like a CRT mounting, I'd
not trust that. I'd cut
off the original pillars, and smooth the inside of the case flat. Then
make new metal pillars, drill and tap them along the axis, and fix them
in place with screws from the outside. Conenct them to mains earth (or
similar), just in case something breaks down and makes the screwheads live.
Umm... NO WAY would I do that as it would completely destroy the
original look of the unit, making it rather pointless to collect.
--
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<http://www.xmission.com/~legalize/book/>
Pilgrimage: Utah's annual demoparty
<http://pilgrimage.scene.org>
5:38 p.m.
In article <m1Ev2Dl-000Iy9C at p850ug1>,
ard at p850ug1.demon.co.uk (Tony Duell) writes:
Come again? The only change to the outside appearance is 4 screwheads on
the CRT bezel. Hardly a big change. A CRT breaking loose and then
breaking would do a lot more damage to the appearance and originallity
of the unit.
And I am wondering why it's pointless to collect stuff which doesn't
_look_ origianl. Who cares what it looks like? These are computers and
peripherals, not fine art. What's important to me is what it does, and
how it does it. Something that's not changed by re-mounting a CRT.
-tony
However, for something like a CRT mounting,
I'd not trust that. I'd cut
off the original pillars, and smooth the inside of the case flat. Then
make new metal pillars, drill and tap them along the axis, and fix them
in place with screws from the outside. Conenct them to mains earth (or
similar), just in case something breaks down and makes the screwheads live.
Umm... NO WAY would I do that as it would completely destroy the
original look of the unit, making it rather pointless to collect.
6:15 p.m.
There's a different between a repair and a mangling. Repairs I'm
willing to do. If I was going to mangle the equipment, I wouldn't
bother buying it.
--
"The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ:
<http://www.xmission.com/~legalize/book/>
Pilgrimage: Utah's annual demoparty
<http://pilgrimage.scene.org>
7:42 p.m.
There's a different between a repair and a mangling. Repairs I'm
willing to do. If I was going to mangle the equipment, I wouldn't
bother buying it.
So epoxy on the inside (to attempt to fix the old posts back in place) is
OK, but 4 screwheads on the outside is not? Neither are 'original'. I
suppose what you should do is to pay megabux to have a mould made up and
make a complet3e new front panel. Alas few, if any, can afford that :-).
To me 'mangling' would be ripping out the insides and replacing them
with, say, a PC + VGA monitor or something.
What would you do if an IC failed and you couldn't get the exact same
replacement? Would you be happy to dead-bug an IC in place? What about if
some external part, like a switch, broke? Would you use one of a
different styling that was electrically equivalent?
And I know I've bought stuff with the express purpose of modifying it, or
even using it for spares (old ISA cards with useful chips in sockets, for
example)
-tony
10:42 p.m.
I'm simply saying something akin to "I don't like pistachio ice cream."
and you seem to be replying as if you're going to convince me that I *must*
like pistachio ice cream.
You can do whatever you want with stuff you acquire.
That doesn't compel me to do what you want with stuff that I acquire.
--
"The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ:
<http://www.xmission.com/~legalize/book/>
Pilgrimage: Utah's annual demoparty
<http://pilgrimage.scene.org>
8 Jan
8 Jan
12:31 a.m.
Tony Duell wrote:
However, for something like a CRT mounting, I'd
not trust that. I'd cut
off the original pillars, and smooth the inside of the case flat. Then
make new metal pillars, drill and tap them along the axis, and fix them
in place with screws from the outside. Conenct them to mains earth (or
similar), just in case something breaks down and makes the screwheads live.
I think I'd go with fixing the original mounts before I tried the above
suggestion. The above would require pretty good machine work, and after
is all said and done would probably be more delicate. Metal pillars
would transmit all shock directly to the outside plastic of the case,
potentially cracking it or punching a hole through it. The plastic
pillar would likely be tapered, so they could be wider at the base, and
if they break again, it would likely still be an internal break again,
not an external one.
Chad Fernandez
Michigan, USA
1:23 a.m.
If this is made of lthe usual ABS or acrylic plastics, it's going to get
weak and brittle with age. On the other hand, if you're dealing with
high-density structural foam, you're somewhat better off, as the stuff is
pretty stable, but harder to repair.
Bottom line, is that if there's a volatile component to the plastic, it's
far weaker now than it was when it was new. Any repair that you make runs
the risk of failure in another part of the structure. While many repairs
will be fine for stationary operation, they may not be robust enough to
survive the rigors of shipping.
You may want to consider removing the heavier parts of the unit and
packaging them separately for reassembly at the destination.
Another option that hasn't been mentioned is fiberglass cloth and acrylic
resin as reinforcement.
Cheers,
Chuck
2:20 p.m.
Chuck Guzis wrote:
If this is made of lthe usual ABS or acrylic plastics,
it's going to get
weak and brittle with age. On the other hand, if you're dealing with
high-density structural foam, you're somewhat better off, as the stuff is
pretty stable, but harder to repair.
Any idea what IBM used in the IBM PS/2 Model 80, and many of the older
RS/6000's? It's some kind of plastic, but not ABS. It's quite fibrous
looking on the inside. It seems to be very strong.
Chad Fernandez
Michigan, USA
5:35 p.m.
On 1/8/2006 at 2:20 PM C Fernandez wrote:
Any idea what IBM used in the IBM PS/2 Model 80, and
many of the older
RS/6000's? It's some kind of plastic, but not ABS. It's quite fibrous
looking on the inside. It seems to be very strong.
Well, I don't have a PS/2 model 80, but various materials can be added as
filler to most plastics to improve strength.
Cheers,
Chuck
9 Jan
9 Jan
8:26 a.m.
Chuck Guzis wrote:
On 1/8/2006 at 2:20 PM C Fernandez wrote:
I'm fond of saying that IBM's plastic is stronger (and heavier) than steel.
Peace... Sridhar
Any idea what IBM used in the IBM PS/2 Model 80,
and many of the older
RS/6000's? It's some kind of plastic, but not ABS. It's quite fibrous
looking on the inside. It seems to be very strong.
Well, I don't have a PS/2 model 80, but various materials can be added as
filler to most plastics to improve strength. 
3:27 p.m.
Any idea what IBM used in the IBM PS/2 Model 80, and
many of the older
RS/6000's? It's some kind of plastic, but not ABS. It's quite fibrous
looking on the inside. It seems to be very strong.
My guess is epoxy resin, based on talking with a (fairly highly
educated) plastics recycler. It appeared that this type material
does not melt as easily as what we call regular plastic.
John A.
10:48 a.m.
New subject: Copying Heathkit manuals
I was wondering about this. Some vendors, like
tektronix say explicitly that this is OK if it
is for a product no longer supported. I'm asking
because I offered to make a copy for a friend (Sine
Square Wave Audio Generator) manual, but I'm not sure
I should. Yes, I know there are gobs of people selling
copies on the net. Ideas?
Jim
__________________________________________
Yahoo! DSL ? Something to write home about.
Just $16.99/mo. or less.
dsl.yahoo.com
8 Jan
8 Jan
1:56 p.m.
Tony Duell wrote:
I have never had a glued repair that is as strong as the original, and
since the mounts cracked ones, they could easily crack again. And a CRT
coming loose is not pleasant!
However, for something like a CRT mounting,
I'd not trust that. I'd cut
off the original pillars, and smooth the inside of the case flat. Then
make new metal pillars, drill and tap them along the axis, and fix them
in place with screws from the outside. Conenct them to mains earth (or
similar), just in case something breaks down and makes the screwheads live.
I think I'd go with fixing the original mounts before I tried the above suggestion. The above would require pretty good
machine work, and after
Is it really that hard to drill a hole along the axis of a cylinder? I
would have thought a 3-jaw self-centring chuck would have been accurate
enough for this sort of thing (I wouldn't bother trying to centre the
work in an indepenedant chuck). And drill with a twist drill in the
tailstock chuck.
is all said and done would probably be more delicate.
Metal pillars
would transmit all shock directly to the outside plastic of the case,
potentially cracking it or punching a hole through it. The plastic
pillar would likely be tapered, so they could be wider at the base, and
So make tapered matal pilars. Make the base as wide as posible (maybe even
wider than the original plastic pillars), and put a decent-sized washer
under the screw head on the otehr side. That should spread the load quite
well.
-tony
9:24 p.m.
Tony Duell wrote:
I have never had a glued repair that is as strong as
the original, and
since the mounts cracked ones, they could easily crack again. And a CRT
coming loose is not pleasant!
I suppose that would depends on what's being glued, and what the glue
is. I've had a pretty good expereince with JB Weld, which is a brand of
two-part epoxy. I haven't used other two-part epoxies, so I don't know
if JB Weld is unique.
Is it really that hard to drill a hole along the axis
of a cylinder? I
would have thought a 3-jaw self-centring chuck would have been accurate
enough for this sort of thing (I wouldn't bother trying to centre the
work in an indepenedant chuck). And drill with a twist drill in the
tailstock chuck.
Owning a lathe certainly opens up greater possibilities, However, I
don't own one, and I suspect most here don't either. I had some sort of
premade standoff in mind, and was thinking the problem would be getting
the old mount ground down flat enough.
So make tapered matal pilars. Make the base as wide as
posible (maybe even
wider than the original plastic pillars), and put a decent-sized washer
under the screw head on the otehr side. That should spread the load quite
well.
Tapered mounts will still require a lathe. Washers on the outside
change the look of the machine even further, and may not even fit
readily on the outside. Tapered mounts may not even fit well on the
inside. Remember the base of many mounts is molded into the sides of
the case via webbed supports. This saves space and strengthens the
mounts. I'm not saying a metal mount definitely won't work, but I am
saying the amount of work to overcome its potentially many short comings
is great. Especially since repairing the original won't change the look
of the machine, and should be a good repair if done right. I did like
your idea of putting a reinforcing cloth around the break.
Chad Fernandez
Michigan, USA
9 Jan
9 Jan
5:26 p.m.
Tony Duell wrote:
In the UK, the most common/first Epozy is called 'Araldite'. Actually,
there are _many_ types of Araldite, but the common one is a 2-part epoxy
that is pretty strong _if it keys to the material you're joining_. My
experience is that Epoxy-type adhesives are not that good on plastics,
disolving and thus welding being stronger most of the time.
I have never had a glued repair that is as strong
as the original, and
since the mounts cracked ones, they could easily crack again. And a CRT
coming loose is not pleasant!
I suppose that would depends on what's being glued, and what the glue
is. I've had a pretty good expereince with JB Weld, which is a brand of
two-part epoxy. I haven't used other two-part epoxies, so I don't know
if JB Weld is unique. Is it really that hard to drill a hole along the
axis of a cylinder? I
would have thought a 3-jaw self-centring chuck would have been accurate
enough for this sort of thing (I wouldn't bother trying to centre the
work in an indepenedant chuck). And drill with a twist drill in the
tailstock chuck.
Owning a lathe certainly opens up greater possibilities, However, I
don't own one, and I suspect most here don't either. I had some sort of premade standoff in mind, and was thinking the problem
would be getting
the old mount ground down flat enough.
A CRT inploding also alters the appearance :-). And possibly the
appearance of other machines and people near it.
Again, as I've said before, I don't care what my machines _look_ like.
They are not pieces of fine art. The beauty is in the design, and
possibly the contruction (but that's not changes by adding a few screws
to the front).
So make tapered matal pilars. Make the base as
wide as posible (maybe even
wider than the original plastic pillars), and put a decent-sized washer
under the screw head on the otehr side. That should spread the load quite
well.
Tapered mounts will still require a lathe. Washers on the outside
change the look of the machine even further, and may not even fit readily on the outside. Tapered mounts may not even
fit well on the
inside. Remember the base of many mounts is molded into the sides of
the case via webbed supports. This saves space and strengthens the
Given a lathe and milling facilities, I am sure you could make something
that would fit. No, I am not suggesting you need a milling machine as
well, most small lathes have milling attachments, such as a vertical
slide. That is perfectly adequate for this sort of job.
mounts. I'm not saying a metal mount definitely
won't work, but I am
saying the amount of work to overcome its potentially many short comings
is great. Especially since repairing the original won't change the look
of the machine, and should be a good repair if done right. I did like
I have never managed to glue a pillar back in place with sufficient
strengly to hold anything (and I know others who have had similar
problems, e.g. in radio restoration/repair). It is generally agreed you
need to put a screw through it.
your idea of putting a reinforcing cloth around the
break.
That works well. I used it to hold an HP9830 keyboard bezel together
(this plastic goes very brittle with age, and the bezels are almost
always shatteresd). I still wouldn't trust it for a stuctural part, though.
-tony
6771
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18 comments
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