November 19, 2011:  How to pack a mirror properly (my way)

This is how I usually pack mirrors up to and including 24" in diameter.  A 26" would probably be OK, too.  Larger mirrors use similar methods, but are packed in wood crates and shipped via freight.

The keys are - use a strong box, tape it securely, and make sure there is at least 2" of foam on all sides of the mirror.  It's nice to have 3" on the sides if possible.  For small mirrors, 1.5" might be enough.  
Sometimes other high-quality, flexible foam is used (the white crumbly stuff is weak, annoying junk), and occasionally cardboard is stacked on top to help fill up a box if there is empty space at the top.

Some shippers might promote the "squishy box" theory - that is, cushion the blow.  However, I'd say that I promote the "foam brick" theory.  The blow may not be cushioned, but a truck could run over the box and the mirror would probably survive.  The harder foam also resists penetrations a bit better than softer stuff.  Admit it - you've received a package with a nasty-looking hole poked in it at some point, so think of that when packing your mirror.

In this example, a 24" x 1.5" mirror is packed into a 30" x 30" x 6" (inner dimension) heavy-duty Uline box.  The box was cut down in height from its original 30".

Uncoated mirrors are easier to clean and less delicate than coated mirrors, because the coating is more easily scratched.  In either case, the mirror should be cleaned before shipping so that dust or dirt do not harm the surface during the vibration and shocks/drops of shipping.

First, the mirror is cleaned.  Then a few layers of acid-free paper is taped over the clean mirror's surface (below).  The paper should not be able to move around.  Acid-free paper will not react with the mirror's surface if the mirror is not unpacked or shipped promptly.  If you don't have it, try to find soft tissue paper free of dyes, lotions, or other chemicals, and try to minimize the time that the paper is agains the mirror's surface.

Acid-free paper on mirror

Next, a cardboard disk is cut and taped securely over the paper, preventing anything from getting in between, holding the paper stationary, and protecting the surface.  A coater once told me that regular masking tape was leaving a residue and was making his job harder, so I immediately switched to the blue painters-type tape.

Cardboard on top of acid-free paper

The mirror is placed in a box with foam cut to fit snugly around it (below).  I use a small, cheap bandsaw to cut out the circular hole for the mirror.  A knife will do a messier job, but will work.  A hot-wire cutter would be nice.

The mirror should not be able to move around, and cardboard can be wedged in around the edges of the mirror or box, or on top of the mirror to take up extra wiggle-room.  In this case, a few pieces of loose cardboard were placed on top to keep the mirror from moving vertically.

Mirror surrounded with foam, bottom and sides

Finally, the box is filled the rest of the way with foam.

Last layer of foam

The flaps are securely taped where they meet, the edges of the box/flaps are taped, and I also run tape around the box to further strengthen it.  Any corners that appear weak are also taped.  Don't forget to check the bottom of the box, where flaps are often not taped.  Use wide, good quality packing tape.  It's worth it.

The goal is to make the box as rigid as possible - any flexure of the box is bad, and will allow the contents to move or shift.  It will also stress the tape, corners, and other weak points of box.

In short, it is my goal to ship a foam "brick" that can only be opened with a knife.

You can also see why I charge for a new packing box.  The foam and box are not free, and it takes me some time to get everything to fit properly.  It is also incentive for the shipper to pack it properly in the first place!

Shipping insurance is an option, but with this type of packing your mirror should withstand rough handling and make it to its destination OK unless the truck goes up in flames or the plane crashes.  That is quite unlikely, and in terms of statistics, the mirror is far more likely to be lost than damaged like that.

To reduce the chance of loss, I print my shipping labels ahead of time and drop the boxes off at a staffed location (usually FedEx/Kinkos) when I am in town.  They don't add additional charges like the UPS Store.  Having a label helps reduce address errors and time spent waiting for a clerk to do it.  I would use UPS if there were a more convenient drop-off location near me that didn't up-charge.

So far the only problem I have experienced was with a small mirror shipped by the USPS, as I was instructed to do by the client.  The post office managed to get the box wet, damaging the coating because it was not immediately dried out.

Here are some more thoughts on packing:

I have to buy 30"x30"x30" boxes in a quantity of 10 each, shipped freight from Uline.  I buy many sizes at a time, and they all show up in flattened form on a pallet.  I have forks for my tractor so I can load and unload crates, pallets, etc.  Most new boxes are too large to ship UPS or FedEx.  Then I have to custom-cut the 30" boxes down to the right height, typically ending up about 7" tall including the thickness of the top and bottom of the box.

I ship up through 24" and 25" mirrors in cardboard boxes.  For these large sizes, the boxes are triple wall and are taped with high strength professional tape, such as 3" Kraft paper tape with strands of reinforcing fibers imbedded in it, and 3" wide clear packing tape.  For lighter, smaller mirrors, double wall works fine.  I take great care in taping up the boxes inside and out to strengthen them, and I tape the corner of the box where the seam is.  Taping properly is very important to the structural integrity of the box.

I like to have a minimum of 2" of foam on all sides of the mirror, and 3" if possible.  For example, I ship a 22" mirror in a 28"x28" box.  I use 1.5" and 2" thick hard foam (typically blue or pink, sold in 4'x8' sheets at home improvement stores) cut as accurately as possible so that the mirror does not have room to bounce around in the box.  The less the mirror can move, the less it will beat up the foam internally.  I have also experimented with hot-gluing the layers of foam together, and reinforcing the sides of the box with thin plywood to help make the box more durable.  Still, shipping large mirrors in a box will lead to the box and packing eventually getting a bit beat up.

When cutting the foam, cut a place where whomever is packing/unpacking the mirror can get their hand under the mirror to lift it out of the foam.  I typically do this closest to the corner of the box, cutting a ~4"x1" piece out of the layer that goes around the mirror, and making a depression in the layer underneath so one can get their fingers under it.  This will encourage nicer handling of the mirror and the box and foam, and this is good all around.

Shipping freight is a pain and can be expensive if you don't regularly work with a freight company like I do, and don't have a machine capable of picking things off trucks.  Avoid it when you can.

It has been my experience that UPS and FedEx see wooden crates as a CHALLENGE, not something that is protecting something inside!  It's like they try to find ways to break them.  They also hate handling them because they are hard to handle and because of splinters. So, if sending a wooden box via these shippers, be nice wrap it in a layer of cardboard or put the wooden box in a cardboard box.  This will help it to be treated more kindly by everyone, in my experience.

If you can find sheets of heavy cardboard (it is sold for packing purposes), you can MAKE YOUR OWN BOX.  Use a roller (dull pizza cutter) to "score" a line along which the cardboard can be folded.  Buy a roll or two of high-quality, 3" wide tape and make TWO boxes, one nested inside the other.  Then put foam inside of that.  That should get your mirror there safely, and it will be re-usable.

Lastly, insurance purchased through UPS and FedEx is expensive.  Also, you may have problems getting a claim simply because the item is glass.  So, you may be paying this money for nothing.  I typically don't insure mirrors of this size - I pack them properly.  (My business insurance covers some of this now.)   If packed properly, the primary risk of shipping is LOSS or THEFT.  So, sign up for a UPS or FedEx account and print the label yourself.  You can get better rates this way, too.

Put tape over it to protect the label.  Also, put another copy of the label inside the box, just in case.  Make quite sure the address you are shipping to is correct, and that someone will be there to sign for it when it is received.  Checking the "signature required" option is a good idea.  Likewise, ask that you be informed when the mirror ships back to you, and get a tracking number.  If you sign up for a free service like "UPS My Choice", you will get an email when something is shipped to you, and you have options to have it held if you are not going to be home, etc.  The best way is simply to be there personally to receive the mirror when it comes back.  All of this greatly reduces the chance of loss.

After you ship or receive your well-packed mirror, please check back for future installements of "In the Shop".

Mike Lockwood
Lockwood Custom Optics

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