How do people pack delicate instruments properly?

[tggzzz]

This is inspired by https://www.eevblog.com/forum/chat/why-can_t-people-pack-items-properly!/msg847263/#msg847263. This thread could go in either the "for sale" or "repair" sections, but I've put it here since people might have a better personal experience of seeing packing done well.

Let's start with a spectrum analyser or oscilloscope with a CRT, for example a familiar Tek 4x5 or something equivalent, because problems/solutions will be common to many types of equipment.

It has controls and connectors protruding all over the fascia. How do you protect

• any/all of them from crushing forces, if the scope is dropped directly onto the fascia or due to the weight of a different package in the transit van. Ideally there would be a strong cage over the fascia which would transmit the force directly to the case (completely avoiding the controls) - but that isn't trivial since the controls are very near the edge
• those at the corners from bending forces, if the scope is dropped on a corner

Possibilities:

• I doubt bubble-wrap would be sufficient in either case. Packing peanuts would be disastrous, since they might end up in a good or bad position
• presumably a custom collar/cage could be made from laser-cut wood, but is there an easier way?
• what about expanding foam? Presumably that is quite rigid once set, but that means if it bends then any external force will be directly transmitted to the controls.
• should the handle be placed against the case away from the fascia, or out in front of the fascia to protect the fascia at the expense of exposing the handle's hinges?

CRTs are inherently vulnerable to shocks. How can shocks be minimised?

• energy-absorbing foam such as Confor would certainly work - but that is excessively expensive.
• multiple layers of bubble wrap would help, provided it doesn't interfere with the fascia problems mention above
• multiple layers of cardboard could act as a crumple zone, but only once
• packing peanuts might be an infill between other parts which keep the peanuts in place
• which compositions of foam work and don't work?

In the end there will probably be at least two layers involving foam, cardboard, packing peanuts and bubble wrap. But what should go in each layer?

So, what are the general principles and techniques that have been successfully used?

[BradC]

I bought a Tek 2440 from the states. It was packed in a big cardboard box with a pair of plastic bags full of pour in expanding foam. I was well impressed as the box had been beaten to death and the CRO (and foam) was pristine. A 2440 is not a light machine but this foam was perfectly moulded around all the delicate bits.

The expanding foam was the perfect balance between firm and flexible. Not like any I've seen or used before.

[HighVoltage]

If you don't have an original box and foam, I think lots and lots of bubble wrap is the best protection.
Use smaller bubbles at the beginning and switch to bigger bubbles to the outside.
I never had a complaint, when shipping expensive instruments like this and always got great comments on packing.

[Ian.M]

Bubble wrap or open cell soft foam padding of sensitive areas that cant take much pressure, then expanding foam into bin bags in a box to make a form-fitted two (or more) part 'nest' for it.   You then put as much extra reinforcement and padding round the outside as you can afford, bearing in mind the likely delivery method.  Hardboard and fiberglass reinforced packing tape are your friends!  If you anticipate it being air-dropped out the back of a C130 Hercules, you obviously have to do a better job than if it is to be handled end-to-end by specialist fragile equipment movers.

It *MAY* be necessary to disconnect and pad the CRT base board and protect the pins with a cardboard tube if its a large/heavy board and isn't otherwise supported, or for valve equipment, remove and pack the valves individually.


 

[tggzzz]

Thanks for some quick and helpful replies.

By "expanding foam", is the

• DIY filling/fixing polyurethane foam such as http://www.polycell.co.uk/product/polycell-expanding-foam-polyfilla/ , or
• easier to use but more expansive http://www.sealedairprotects.com/eu/en/products/foam_packaging/foam_protection_bag_works.aspx

suitable?

If not, then is there an example of something better?

[wraper]

Thanks for some quick and helpful replies.

By "expanding foam", is the

• DIY filling/fixing polyurethane foam such as http://www.polycell.co.uk/product/polycell-expanding-foam-polyfilla/ , or

[/b]

• easier to use but more expansive http://www.sealedairprotects.com/eu/en/products/foam_packaging/foam_protection_bag_works.aspx

suitable?

If not, then is there an example of something better?

That is construction foam. You could use it in theory, but I'd like to watch the circus how it will happen in reality. Also it unlikely to be cheaper, there in not much volume in there.

[bitslice]

Hah,
I've just looked up that Instapak foam stuff on eBay, it's like 40p a bag! 

That's a no-brainer if I needed to ship anything that weighed a few kg to someone,
in fact next time I buy something I'm going to suggest they use it and I'll cover the cost. I'm just so sick of functional retards on eBay sending me a box of bits all the time.


edit: actually it looks like someone is just offloading a few, so I bought some, normally it's way too expensive.
I'm going to pack up some of my unused equipment for storage.

[tggzzz]

That is construction foam.

Just so.

The video is of "sealedairproducts" instapack; is that your suggestion? If so, when you used it or received it, were there any particular techniques you liked?

[Cerebus]

CRTs are inherently vulnerable to shocks. How can shocks be minimised?

• energy-absorbing foam such as Confor would certainly work - but that is excessively expensive.
• multiple layers of bubble wrap would help, provided it doesn't interfere with the fascia problems mention above
• multiple layers of cardboard could act as a crumple zone, but only once
• packing peanuts might be an infill between other parts which keep the peanuts in place
• which compositions of foam work and don't work?

There's a neat technique I've seen using two elastic membranes that works well for lighter items up to a few Kg. I haven't any old packaging that uses this technique to photograph so I'll just have to try and describe it.

Imagine the outer cardboard box. Now imagine two more cardboard boxes that just fit inside the outer box, each box is half the height of the outer so that they meet at a surface that forms halfway through the outer box. There's a circular or oval hole cut in the inner boxes where this interior surface is and two pieces of elastic polyurethane sheet are stretched across that hole, each one firmly attached to its respective box. The item to be transported is held in place between the two stretched membranes so that they form a suspending elastic cradle around it.

In practice this doesn't use two boxes, but a sheet of cardboard that is folded so as to make a cradle with most of the surfaces of those boxes but without the very top and very bottom surfaces and that is hinged on one of the long edges of the interior surface. Make the membranes strong enough and elastic enough and there would really be no limit on how big or heavy an item you could pack like this. An added advantage is that the whole contraption is very light and the outer edges of the cradle strengthen the outer box too.

[tggzzz]

There's a neat technique I've seen using two elastic membranes that works well for lighter items up to a few Kg. I haven't any old packaging that uses this technique to photograph so I'll just have to try and describe it.

Yes, I've recently seen that technique when browsing for packaging. As you imply, it isn't really applicable to a 20kg instrument!

If I was being truly picky I'd question whether it is good w.r.t. shocks in all three axes. No problems with the axis perpendicular to the membrane, but not so good for the two axes in the plane of the membrane. Perhaps in extreme cases a nested "gimbal" mount would be necessary - but if that's the case (ho ho), then maybe springs would be better.

[TopLoser]

I use duvets whenever I ship large heavy things without original packaging. Tesco or Morrisons have nice thick double or kingsize ones on sale for £8 every now and then, worth it for expensive equipment. Plus they can be used at the other end.

[Jwalling]

Hi density foam rubber foam salvaged from discarded sofas works great, and it's free! 

Jay

[Cubdriver]

I think the key is a combination of shock absorption and immobilization.  You want something that 'gives' a bit to reduce the acceleration spikes as the package is bounced about, but at the same time you want to keep it cradled firmly so that it doesn't wind up bouncing around inside the package.

I haven't taken any pictures (will try to remember to on my next go-round), but when I ship the typically heavy HP stuff I get on my trips to CA back home, I generally use plastic film and foil backed Styrofoam insulation sheets cut to line the box and immobilize the equipment.  I get it in 4' x 8' sheets, in 1" and 2" thicknesses at Home Deport.  It's not cheap, but then again neither is what I'm shipping (to me, at least).  The plastic film/metallized plastic foil backing helps a great deal to keep the Styrofoam from shedding little bits everywhere; the only places the raw foam is exposed is along the cut edges.  One box packed this way contained an 8565A spec an, a 3490A DMM and I forget what else I stuffed in there and weighed in at over 100 lbs; it arrived unscathed.

I try to come up with a box that's at least 4" larger on all inside dimensions (to allow 2" minimum clearance between the instrument and the box on all sides) and start by lining it with 2" thick foam cut to fit to within an eighth of an inch of the inside of the box; usually doing the sides first with pieces cut to fit the inside height of the box, then cutting bottom & top pieces to fit snugly within these walls.  The foam box-within-the-box seems to greatly strengthen the outer cardboard box and reduce the likelihood of it being crushed enroute. 

If an instrument has feet and they're removable, I take them off and pack them separately - this lets the broad surface of the cabinet bottom sit on the foam thereby spreading the load out over a large area rather than concentrating it at the feet, which would then poke into the Styrofoam.  The instrument is put into its foam cocoon and wedged in place as needed with smaller pieces of Styrofoam, ethafoam or sponge foam, depending on what's handy at the time.  Folded bubble wrap may also occasionally be used as a gap filler, and lighter things (less than perhaps 20 lbs or so) may also be wrapped in it before going into the foam.  Styrofoam strips are inserted as needed between the instrument's front panel and the inner wall of the foam 'box'; I cut them to size and position them to bridge the gap between the panel and the wall and fit between buttons, knobs or display faces - the relatively delicate things are kept free in a small air space, but the strips keep the panel separated from the wall. 

I cut the larger pieces with a razor knife and drywall square or other metal straightedge, and sometimes zing through smaller pieces on the band saw when able as it's quick and sort of heat seals the cut edge a bit too.

It takes a good bit of effort and on the fly planning as things are boxed up, but so far I've had good success getting things across the country after packing them like this.  I'll try to remember to take some photos next time.

-Pat

[tggzzz]

Thanks for your detailed thoughts.

I think the key is a combination of shock absorption and immobilization.  You want something that 'gives' a bit to reduce the acceleration spikes as the package is bounced about, but at the same time you want to keep it cradled firmly so that it doesn't wind up bouncing around inside the package.

Agreed. I mentioned Confor since it halves the transmitted energy because it doesn't bounce back. For that reason it is used in ejection sets and glider seat cushions.

I haven't taken any pictures (will try to remember to on my next go-round), but when I ship the typically heavy HP stuff I get on my trips to CA back home, I generally use plastic film and foil backed Styrofoam insulation sheets cut to line the box and immobilize the equipment.  I get it in 4' x 8' sheets, in 1" and 2" thicknesses at Home Deport.  It's not cheap, but then again neither is what I'm shipping (to me, at least).  The plastic film/metallized plastic foil backing helps a great deal to keep the Styrofoam from shedding little bits everywhere; the only places the raw foam is exposed is along the cut edges.  One box packed this way contained an 8565A spec an, a 3490A DMM and I forget what else I stuffed in there and weighed in at over 100 lbs; it arrived unscathed.

Useful. The benefits of the film/foil are a good idea.

I try to come up with a box that's at least 4" larger on all inside dimensions (to allow 2" minimum clearance between the instrument and the box on all sides) and start by lining it with 2" thick foam cut to fit to within an eighth of an inch of the inside of the box; usually doing the sides first with pieces cut to fit the inside height of the box, then cutting bottom & top pieces to fit snugly within these walls.  The foam box-within-the-box seems to greatly strengthen the outer cardboard box and reduce the likelihood of it being crushed enroute.

So the cross section from the outside is cardboard, foam, styrofoam, instrument.

If an instrument has feet and they're removable, I take them off and pack them separately - this lets the broad surface of the cabinet bottom sit on the foam thereby spreading the load out over a large area rather than concentrating it at the feet, which would then poke into the Styrofoam.  The instrument is put into its foam cocoon and wedged in place as needed with smaller pieces of Styrofoam, ethafoam or sponge foam, depending on what's handy at the time.  Folded bubble wrap may also occasionally be used as a gap filler, and lighter things (less than perhaps 20 lbs or so) may also be wrapped in it before going into the foam. Styrofoam strips are inserted as needed between the instrument's front panel and the inner wall of the foam 'box'; I cut them to size and position them to bridge the gap between the panel and the wall and fit between buttons, knobs or display faces - the relatively delicate things are kept free in a small air space, but the strips keep the panel separated from the wall. 

I'd wondered about styrofoam-between-buttons, but on some instruments with many protruding controls I'm concerned there wouldn't be much there!

I cut the larger pieces with a razor knife and drywall square or other metal straightedge, and sometimes zing through smaller pieces on the band saw when able as it's quick and sort of heat seals the cut edge a bit too.

As a kid I remember cutting the newfangled styrofoam with a hot knife (couldn't afford a hot wire!).

[edpalmer42]

I've seen lots of equipment packed with pieces of expanded polyethlene foam (I think that's what it is) molded to fit around the corners or edges of the unit.  The foam is tough but still spongy.  It won't break like styrofoam and is strong enough to absorb multiple impacts and still provide protection.  I've also seen it in sheets.

Ed

[bitseeker]

Anything with a CRT worries me because even if the exterior is well-protected, the neck is potentially quite vulnerable. Variacs may be similarly vulnerable depending on how they're assembled. One that I purchased was mounted inside a metal box enclosure with a nice analog panel meter. I asked the seller to open it and stuff around the toroid. When it arrived, I found old rags stuffed inside. Nothing bent.

Below is some general info on how I pack stuff for shipping when I don't have an original shipping container and/or inserts for it.

Inspecting the item thoroughly is critical to know what you're up against, especially for bits that stick out.

The primary inner layer of protection is lots of bubble wrap. If there are knobs to protect such as on a front panel, I'll cut the bubble wrap wider than needed and bundle it up for several inches of extra protection. Even if it gets a direct strike, the force will be distributed around the controls. If there is a significant amount of disparity in spacing and knob/post heights, I may apply separate bubble wrap in between to even things out before closing the main layers of bubble wrap over it.

The outer layer is the box, which is selected to allow enough space for the item, all its bubble wrap, and the intermediate protection layer. The amount of space allowance is larger for heavier or more delicate items.

The intermediate layer depends on the weight of the item. If it's not too heavy, I'll fill the space with air pillows. Amazon uses these, except they usually don't use them properly. Amazon will place the item directly on the bottom of the box and throw some pillows on top just to say they did something. When I use them, the result is that the item is suspended on all six sides and immobilized.

For heavier items, I use packing bits. They come in all kinds of shapes (peanuts, cylinders, balls, etc.) and sizes. The important things are not to skimp on them and to settle the material as the item is being packed. Just throwing it in and closing the box because it looks full is about as useful as whipped cream.

Before finalizing the box with tape, I tack the box top closed with a few short pieces of tape and shake it in various orientations to listen and feel for any movement. It should feel like a solid block. There should be no indication that any object is inside. If necessary, add more stuffing.

When I head out to the shipper the next day, I'll shake the package again, just in case.

The biggest/heaviest item I've shipped was an HP 8591E spectrum analyzer (CRT display) without the protective front cover and the rear posts/feet attached. What a beast that was. It went cross-country unscathed.

[tggzzz]

I've seen lots of equipment packed with pieces of expanded polyethlene foam (I think that's what it is) molded to fit around the corners or edges of the unit.  The foam is tough but still spongy.  It won't break like styrofoam and is strong enough to absorb multiple impacts and still provide protection.  I've also seen it in sheets.

It might be ethafoam https://www.efoam.co.uk/ethafoam-packaging-foam.php or conceivably https://www.efoam.co.uk/zotefoam-plastazote.php

A question is whether it is possible for an amateur to mould it around the corners or, if not, how to deal with them, e.g. cutting with a knife or gluing multiple layers together

[tggzzz]

Anything with a CRT worries me because even if the exterior is well-protected, the neck is potentially quite vulnerable.

Yes indeed! Fortunately Tek 4x5 scopes aren't too bad in that respect. They were designed to fit under the aircraft seats. I even took one on two flights to a war zone (Belfast) as hold baggage, with zero wrapping. Perhaps people were more careful then, perhaps it was the "unwrapped glass aquarium" effect.

The primary inner layer of protection is lots of bubble wrap. If there are knobs to protect such as on a front panel, I'll cut the bubble wrap wider than needed and bundle it up for several inches of extra protection. Even if it gets a direct strike, the force will be distributed around the controls. If there is a significant amount of disparity in spacing and knob/post heights, I may apply separate bubble wrap in between to even things out before closing the main layers of bubble wrap over it.

I would definitely want to have good support between/around the controls. They are a notorious problem area.

For heavier items, I use packing bits. They come in all kinds of shapes (peanuts, cylinders, balls, etc.) and sizes. The important things are not to skimp on them and to settle the material as the item is being packed. Just throwing it in and closing the box because it looks full is about as useful as whipped cream.

Just so. In order to keep them in place and/or evenly distributed, I'm wondering if it is sensible to have a "skeleton" made from foam, and to have peanuts between the skeleton.

Before finalizing the box with tape, I tack the box top closed with a few short pieces of tape and shake it in various orientations to listen and feel for any movement. It should feel like a solid block. There should be no indication that any object is inside. If necessary, add more stuffing.
When I head out to the shipper the next day, I'll shake the package again, just in case.

Yes indeed

[Cubdriver]

My experience with insta-pack type foams has been mixed.  For things that are not terribly heavy and/or that have a large surface area to distribute the loads, it's fine, but heavy/dense things will crush it and get loose.

A company I previously worked for sold and distributed RF generators that were made in Germany.  They were fairly heavy (usually 30 or more pounds, IIRC), and were in rack mount enclosures, a few inches longer than they were wide.  The most popular ones were 2 RU tall (about 3-1/2").  Initially, they were shipped in double wall boxes with foam rubber corner blocks (picture a cube with a smaller cube cut out of one corner); one was placed in each corner of the shipping carton with the cutouts facing in; the unit was then placed in with its corners sitting in the cutouts and four more corner blocks placed on its the top corners.  When the box was closed up, the chassis was then suspended in the center, with the corners held in place by the blocks.  Generators shipped this way arrived in fine condition.

Then at some point they got a foam-in-place packing system.  Line the box, squirt in foam, cover it with the plastic membrane, put the generator in, cover it with membrane, foam the top, cover that and shut the box.  Generator mummified in nice soft foam, cradled on every surface.  Sounds great, right?  Not so much.  I got really good at doing body & fender work, and straightening bent rack mounting ears. 

The generators were held wonderfully in the vertical direction, where their 30+ lb weight was distributed over several square feet of area, but the sides/corners were another matter entirely.  The joint between the foam sections, where the foaming would be incomplete and leave at least small gaps lay right on the narrowest dimension of the enclosure - the height.  As the boxes were bounced around in shipment, the large forces concentrated on the sides combined with the sharp edges of the rack mounting ears would begin to crush the expanded foam surrounding the edges of the generators, permitting them to slide a bit in the horizontal direction.  Once they began sliding, they would build up inertia and hit the foam harder, pulverizing it and permitting even more movement.  Before long, the ears were hitting the inside of the box and getting bent.  I would guess that 3 out of 5 had some damage, with some being buggered to the point that they needed new front panel sheet metal (the rack ears were extensions of the panel itself). 

The problem could easily have been alleviated with some 'L' shaped ethafoam blocks in the corners to resist the greater force on horizontal plane further compromised by the seam where the top and bottom foam halves met, but alas they never did it.

TL, DR - foam in place is a great packing material in many cases, but not well suited to small, dense objects.  They will crush the foam, get loose and hurt themselves or others.

-Pat

[helius]

The original packaging from the manufacturer is always the reference for this kind of job.
The Tektronix 465/475/485, for instance, came with front covers that contain a custom polystyrene foam insert to protect the switches. This has nearly always been separated from the instrument over the years.

[Cubdriver]

Thanks for your detailed thoughts.

My pleasure.  I also have direct experience with this method as I'm shipping things to myself.   

Useful. The benefits of the film/foil are a good idea.

Unfortunately all I can attribute that to is a happy accident - it's the only type of foam the HD near the California office sells in big sheets, so it's basically Hobson's choice.

So the cross section from the outside is cardboard, foam, styrofoam, instrument.

Close - it's the cardboard box, 2" styrofoam lining, then the instrument with any additional padding I might need or decide to add - may be nothing more, might be small pieces of the insulation foam cut to fit, bubble wrap, etc.  It depends on the instrument and how tightly it fits in the space.

I'd wondered about styrofoam-between-buttons, but on some instruments with many protruding controls I'm concerned there wouldn't be much there!

That can sometimes be challenging, but luckily for me in most cases so far it's been more supplemental, used with HP instruments that have the built in rack handles extending forward.  The faces of the handles are butted up against the Styrofoam wall providing the main opposition to movement in that direction, and I add some bits and pieces of foam were possible to provide additional bearing surface and spread the forces out more.

As a kid I remember cutting the newfangled styrofoam with a hot knife (couldn't afford a hot wire!).

I've never really tried a hot knife or wire.  I don't know how well it would work on this kind of foam due to the plastic membrane covering the faces.

I'll take some photos of the next one I do.  There's still about 200# of stuff out there to come home (the 2401C voltmeter, 2410B ac/ohms converter, a 5360A computing counter and a 2402A DMM off the top of my head...)  Those should be great fun to package up as they're in the neighborhood of 50 lbs each.  Fun, fun!!

-Pat

[bitseeker]

Just so. In order to keep them in place and/or evenly distributed, I'm wondering if it is sensible to have a "skeleton" made from foam, and to have peanuts between the skeleton.

Compartmentalizing is also helpful if the box is compromised. The extent to which one goes to package an item depends on many factors such as value, insurance coverage, scarcity, carrier reputation, distance, and destination location, etc.

[bitseeker]

There's a neat technique I've seen using two elastic membranes that works well for lighter items up to a few Kg. I haven't any old packaging that uses this technique to photograph so I'll just have to try and describe it.

I've seen that suspension system several times including for shipping a laptop back to the factory for warranty repair. It's pretty neat, but seems a bit unnerving. If the membrane failed, the device would be mostly free inside the box (much like Amazon's default packaging method).

[tggzzz]

My experience with insta-pack type foams has been mixed.  For things that are not terribly heavy and/or that have a large surface area to distribute the loads, it's fine, but heavy/dense things will crush it and get loose.

A company I previously worked for sold and distributed RF generators that were made in Germany.  They were fairly heavy (usually 30 or more pounds, IIRC), and were in rack mount enclosures, a few inches longer than they were wide.  The most popular ones were 2 RU tall (about 3-1/2").  Initially, they were shipped in double wall boxes with foam rubber corner blocks (picture a cube with a smaller cube cut out of one corner); one was placed in each corner of the shipping carton with the cutouts facing in; the unit was then placed in with its corners sitting in the cutouts and four more corner blocks placed on its the top corners.  When the box was closed up, the chassis was then suspended in the center, with the corners held in place by the blocks.  Generators shipped this way arrived in fine condition.

Then at some point they got a foam-in-place packing system.  Line the box, squirt in foam, cover it with the plastic membrane, put the generator in, cover it with membrane, foam the top, cover that and shut the box.  Generator mummified in nice soft foam, cradled on every surface.  Sounds great, right?  Not so much.  I got really good at doing body & fender work, and straightening bent rack mounting ears. 

The generators were held wonderfully in the vertical direction, where their 30+ lb weight was distributed over several square feet of area, but the sides/corners were another matter entirely.  The joint between the foam sections, where the foaming would be incomplete and leave at least small gaps lay right on the narrowest dimension of the enclosure - the height.  As the boxes were bounced around in shipment, the large forces concentrated on the sides combined with the sharp edges of the rack mounting ears would begin to crush the expanded foam surrounding the edges of the generators, permitting them to slide a bit in the horizontal direction.  Once they began sliding, they would build up inertia and hit the foam harder, pulverizing it and permitting even more movement.  Before long, the ears were hitting the inside of the box and getting bent.  I would guess that 3 out of 5 had some damage, with some being buggered to the point that they needed new front panel sheet metal (the rack ears were extensions of the panel itself). 

The problem could easily have been alleviated with some 'L' shaped ethafoam blocks in the corners to resist the greater force on horizontal plane further compromised by the seam where the top and bottom foam halves met, but alas they never did it.

TL, DR - foam in place is a great packing material in many cases, but not well suited to small, dense objects.  They will crush the foam, get loose and hurt themselves or others.

That makes a great deal of sense. Thanks.

[tggzzz]

The original packaging from the manufacturer is always the reference for this kind of job.
The Tektronix 465/475/485, for instance, came with front covers that contain a custom polystyrene foam insert to protect the switches. This has nearly always been separated from the instrument over the years.

Very true, especially w.r.t. the front covers. They can be bought on ebay for ~£35 (and rising).

Some Tek manuals give hints and diagrams for packing, but the details are missing - and techniques may have improved in half a century.