Can your time capsules be engraved?

Yes! You can order any time capsule lid to be engraved via the laser engraved marking method. This is a high quality indelible marking that lasts hundreds of years. Lids of the cylindrical time capsules can be laser engraved, but you also can choose a very simple character engraving (no logos or images). Due to equipment limitations, we cannot do simple engraving on the box time capsules.

Note for 2023: Until our company store is completely moved from our current location, we cannot do personalizing of time capsules (engraving on the lid) or custom metal plaques. This is temporary.

Can you bury your time capsules in the ground and be sure it will keep all moisture and corrosion out?

Yes. All of our time capsules, unless otherwise noted on the product (e.g. the Indoor Sally 3x12 Time Capsule #35121) can be buried in the ground safely. Each of the time capsules comes with easy to follow instructions for extending the life of the seal.

Are your time capsules inner or outer dimensions?

All of our Box Time Capsules go by inner dimensions, so the 12 x 12 x 16” Gemini, for instance, measures exactly that on the inside. Cylinders are best assumed to be outer dimensions. Our cylinder time capsules measure, in outer dimensions: 6 x 24”, 5.5 x 22”, 7.75” x 9”, and 3.5” x 11-3/4”. Please call our office with any questions.

What material and what grade are your time capsules made of?

Both the Box Time Capsules and Cylinder Time Capsules are made of 304 Stainless Steel.

What is the difference between the two Box Time Capsule designs you have?

Both are made of 304 stainless steel. The simple capped Box Time Capsule, our Model 4200, is essentially a lid and a body that fit together snugly with just enough clearance for the sealant to be applied. The bolted Box Time Capsule, our Model 3000, is a more complicated design that includes a 1/2” flange that is machined for bolts to be inserted blindly – no moisture or air can seep through it. This flange has a machined groove and our formed silicone o-ring fits exactly to properly seal the lid when all 12 bolts are applied. For up to 75 years storage, you should consider the simpler design; for 100 or more years, you should consider the bolted design.

About how many sheets of letter sized paper will fit into a 12x12x24” Time Capsule?

If no other enclosures are used, you can fit 5,335 sheets of a 20 lb paper (we used Permalife® for this test), into our 12x12x24 Neptune Time Capsule Box.

Our city has several 10" x 13" x 3" archive boxes that we want to place inside one of your bolted time capsules. I would like know the exact diameter of the circle opening, and know if this size archive box will fit through the opening.

The first part of your question is easy. Our 12" x 12” bolted capsules have an opening whose diameter is 9.25"; 14" x 14” ones have an opening diameter of 11.25"; and 16" x 16” time capsules have an opening of 13.25" in diameter.For the second part – as to whether your box will fit through the opening – you would need at least the 14x14 size Bolted Time Capsule. Here’s how we figured this answer. Work with your smaller two dimensions. The 12" bolted TC (diameter of 9.25”) would accommodate up to a 8.75" box of 3" thickness; the 14" TC up to a 10.8" x 3" box; and the 16" TC up to a 12.9" x 3" box. In your case, for the 10” x 3”, the archives box will fit into the 14" bolted capsule opening of 11.25” diameter.

 Is a vault necessary if we need to bury our time capsule?

No, although there are sometimes reasons for doing so, such as for physical and mechanical protection from earthmoving equipment, as well as some protection from earth movement. If you construct a vault, or use a pre-fabricated one, pay attention to how it drains. As for placement, the time capsule should not receive more water than usual, such as would placement in a garden setting. In the same vein, never wrap our time capsules in plastic. The plastic will hold moisture to the metal, and instead of protecting it, it would hasten corrosion over time.

Why aren’t your stainless steel time capsules as thick as the aluminum ones sold by other companies?

Stainless steel is a stronger material than either aluminum or copper, and this, in addition to its superior corrosion resistance, makes it a preferable material for time capsule fabrication. Simply put, you don’t need as thick of a wall with stainless as you do with aluminum. Less of it is eaten away over time.In 1998, we had a professional assessment of our time capsules. He offered the following additional technical information as it applies to the 14x14x24" bolted size time capsule, but the information also applies to our other sizes. In answer to why we make our side wall thicknesses .075" and not .25" thickness of 304 stainless steel:"A time capsule buried in dry soil will not experience an even pressure distribution, as it would if it were suspended in a liquid or a gas. With the capsule oriented vertically, the primary loads would be exerted on the top and bottom. Side loads would be insignificant, unless the soil were to become saturated with water and unstable. I assume you are not putting it in that kind of an environment. Our 14x14x24" bolted time capsule can withstand loads in excess of 200 lbs distributed over each of the 14x24" sides without significant deflection. In addition, it can sustain a vertical load well in excess of 10,000 lbs distributed over the top surface.

"Can you get more items into a box than you can a cylinder?

Yes! Let’s compare the area of each shape. It’s just a little more than ¾ in the example below. You figure a cylinder’s area using the formula pr2h, where pi is 3.14159, r is the radius (half the diameter) and h is the height of the cylinder.You figure the area of a box by taking Length times Width times Height (LWH), where L is the length of one side, W is the measurement or width of another side, and H is the height of the box.Taking an example, a 12”x12”x24” cylinder has an area of 3.14159 times 6” times 6” times 24”, which equals 2714 cubic inches. The same size box has an area of 12” times 12” times 24” or 3456 cubic inches. And practically speaking, archives materials such as documents and books fit better into boxes. You will have less wasted space, in most cases.

How do I figure the amount of oxygen absorbers I need for a time capsule?

First, you need to calculate the amount of air that will remain in the capsule after you've filled it. Let's say your capsule is 8"x10"x18". You see it is rather full except for 1" along one side and 2" on top. Take 1"x18"x10" and add the cubic amount you get from the top, 2"x8"x10" (180 cu. in + 160 cu. in. = 340 cu. in of air remaining in your capsule).Now, you need to convert it into milliliters (ml). Use a chart, or conversion table, (or most online search engines) or figure it out directly. To calculate manually, multiply the 340 times 29.6 (ml), which equals 10,064. Divide that by 1.8 cu in to get the volume of air in terms of ml--that leaves 5,591. The calculator gives you 5572 cc, which = 5572 ml. Don’t worry about the differences, just round up to be safe. We’ll use 5600 in this example.Next, not all air is made up of oxygen. To estimate the amount of oxygen in this air, take 1/5 of 5600 (oxygen content in air is about 20%) and that leaves you 1,120 ml of oxygen to treat.Next, consider the packet size. Let's say you use the 1000 cc size (1 cc= 1 ml) so you simply divide the 1,120 by 1000 to see how many of that size packet you'll need. Take the whole number and round up to the next whole number. 1120 divided by 1000 leaves 1.12, so just order 2 packets of 1000. It just happens that we provide 2 packets of 1,000 cc oxygen absorber for the 10x8x18 Earth Time Capsule. We figure the amount to give you based on the capsule being ¾ full. Then we round up.Having more absorbers than you technically need is okay, and better than not having enough. Just place the amount of absorbers provided into the time capsule before you seal it up.

Do you include anything in the Box Time Capsules that you don’t in the Family Time Capsule Cylinders?

All time capsules (except the indoor Sally 3x12) come with a sealant kit and desiccant, but we do not provide Oxygen Absorbers for the Family Time Capsules unless you get that option. The reason is that many families do not bury their time capsules, and many will add to it over the years. Most Box Time Capsule users do bury or place their boxes for lengthy periods, however, so we do include the Oxygen Absorbers for those. 

Which makes a better Plaque, Aluminum or Bronze?

Since our plaques have a lifetime guarantee, our answer is, “Whichever one you prefer.” Many people prefer Bronze for their memorial plaques, due to its excellent aging properties and its patina color that it develops over time. With bronze, the coloring of your letters would be a gold or yellow coloring. Aluminum Plaques are also popular, however. The color of your letters with aluminum would be a silver or gray color. We recommend a coating on the plaque. For harsh environments, you can specify the coating be applied to both the front and back of the plaque.

Why does the artwork for a plaque or engraving need to be a certain format? What do you mean by ‘vector’? Why can’t I use a web picture, a Word file, or a *.jpg file?

Pictures for the web and those embedded into a Word file are not of good quality, but even a high quality *.jpg or *.tif is still not vector art.Vector art, or "vector-based art," is a technique that creates paths and points in a program such as Adobe Illustrator, Freehand, or CorelDraw. It is often the original program that created your logo or art. Such a program keeps track of the relationships between these points and paths. Vectors are any scalable objects that keep their proportions and quality when sized up or down. They're defined as solid objects, and can be moved around in full, or grouped together with other objects. You create vector art by using a vector illustration program.

 When you submit artwork to us, it must be:
  • Black-and-white, and 
  • In a vector-based file, and
  • Have no grayscale and no screens
Acceptable file formats include:
  • Adobe Illustrator - up to Illustrator 15 (CS5) *.ai (preferred), 
  • orCorel Draw – X5 or below *.cdr, or
  • Certain *.eps and *.pdf files are acceptable, but only if they were made in vector format 

Fonts: Unless we can find a similar font or unless it is a standard one, any special fonts should be converted to curves or outlines.

Of course, we can do modifications or touchup using our program in many cases, but if it requires time (and it usually does), it must be charged separately. We can also recreate a logo or artwork for an additional charge. When in doubt, send the file to us and ask.

What about polyethylene zip bags for protecting items?

They are better than nothing, but don’t expect them to do much. While the uncoated polyethylene isn’t harmful to your items when properly stored, all polyethylene is limited in its protection abilities. People expect too much from its protection. People hear stories about plastics lasting forever, hurting our landfills and so forth. Naturally, they think their items will last inside of them forever. Not so. Be prudent in your use of plastics. We have decreased the amount of plastic bags in our preservation kits recently. You can still use them (and use any that are in our kits or packaging) for segregating things inside the container that you might not have better enclosures for, or for an outer enclosure for the good paper envelopes, for instance.

How long will your time capsules last? I have seen companies claim their plastic capsules will last hundreds of years.

Well, plastic may last hundreds of years but this does not mean the items inside will fare well over time in them. Plastics crack, and they change molecularly over time. If you decide on a plastic time capsule, limit the time of storage and limit any adverse environmental limitations placed on them. We would recommend against burial of those time capsules.

Our time capsules are made from 304 stainless steel, which is low in carbon. Our welders are skilled and certified, and our quality inspector looks for seam problems and fabrication errors before we ship any of them. Even our irregular cylinder time capsules are inspected as to function, so any irregularity in them will be in slight cosmetic appearance only. 

How long your time capsule will last really does depend on the conditions the container must withstand over the number of years in storage. The following estimates for our buried time capsules are far less than if they were stored indoors or in a cornerstone, as we are conservative in our estimates. We provide the sealant & optional wax to extend the potential successful storage time.

  • Cylinder Time Capsules “Future Line” 6x24” & 5.5x22” – 50 to 75 years or more when buried according to instructions and recommendations
  • Cylinder Time Capsules “Future Line” 7.75x9” (77590sd) and 3.5x12” (35120sd) - 50 to 60 years or more when buried according to instructions and recommendations
  • Box Time Capsules 4200 Capped Style: 50 to 75 years or more when buried according to instructions and recommendations
  • Box Time Capsules 3000 Bolted Style Special Order: 75 to 100 years or more when buried according to instructions and recommendations.

I have a few questions about the Sally 3x12" (35120sd) time capsule. I am considering it as a buriable (but later recoverable) container for pet (cat) cremains. Would this container be suitable for that?

Yes, it would be fine for that purpose. I would recommend some additional desiccant (maybe 2 packs of ½ unit size) or silica gel packs (2 of the 10 gram). It comes with a wax/sealant kit, which you will need, and when applied properly, the sealant can be cut away when the time comes to open the container.

Are the time capsules shipped with the label attached?

No, the Time Capsule Label is provided blank and is not applied. You can fill it out with a Sharpie pen or omit it entirely. 

Can you tell me what the benefits of buying a time capsule from you, over using a stainless steel flask? We have a vacuum stainless steel flask which is designed to be air tight, but we're not sure if we need to purchase something specifically designed for time capsule use. We want it to last 50 years. It seals with a heavy duty plastic screw cap with a stainless steel cover.

No, it would not be comparable. The capsules we sell have a threaded cap, and they are 100% stainless steel. Your flask is only partially stainless steel, and the stainless steel cap is designed to be used as a cup or cover – it is not a real lid. The plastic screw cap is not good enough on its own. If you insist on using it, I would recommend against burial, certainly. If you still wish to bury it, you should consider at least sealing the cover part where it meets the bottom, with a sealant such as our Silicone Sealant/Wax Kit. IF you are sealing stainless steel to stainless steel, this type of container would be most similar to our older style Sally, which has a friction fit lid that just pops open. We do not recommend that container be buried. In addition, the most common stainless is grade 302, an inferior stainless grade to the 304 which we use. There is more chance of corrosion over the 50 years you want it to last (and not leak).In short, the flask container you wish to use was not designed to be a time capsule container.

How can we preserve newspapers?

For just one or two newspapers, consider our Newspaper File Kits. The 12x15 size fits most newspapers folded once, the 14x24 fits many modern sized city newspapers, and the 16x24 fits many older ones. What’s nice about these is that they are easy to use, and go far to protect newspapers better than you probably are already. The zip plastic pouches should be stored in the dark to keep the light away. As an important insert to these kits is the special Alpha Rag™ absorber paper and a 2-gram packet of silica gel. Now, with these kits you get one free leaflet on how to preserve newspapers.

 My sorority is having a 100 year celebration and are considering burying a time capsule in the garden at the ceremony. Could you suggest a product for us to use?

 It would contain photos, newspapers and other items. We’d like it to last 50 years.Most popular for many customers is the 6” x 24" Mr. Future Time Capsule. It does need to be placed in an upright position (think post hole digger) and do not place in an area that is watered regularly (place large rock or paved area above it (with plaque) for security). We recommend that you make it a bundle with the matching preservation kit and oxygen absorbers. Or, consider the package version that also includes an 8” x 10” plaque. 

I'm interested in ordering 100 of the personal 3x12 Indoor Sally Time Capsule Set, but need more information first. Do you have that many in stock? Do I get any discount?

Yes, we do have that many in stock currently. Customers interested in bulk orders for any of our items should contact us by phone (1.626.966.1955) for a special quotation and delivery information.

Do you make custom size boxes? If so, can you tell me how much a capped stainless steel time capsule box 32" L x 20" W x 12" D would be?

Yes, in some cases we do make custom boxes, especially to fit cornerstones. However, that size for stainless steel is very heavy and unwieldy to work with. We recommend ordering two of our 12x12x20” Uranus time capsules (, or even two of the 14x14x20” Pluto time capsules ( However, I’m not sure of the size constraints you have to work with. Give us a call.

I went to Mercy Cross high school Nd graduated in 1987. We buried a time capsule I believe in the mid 80s. It could have been purchased by the Catholic Diocese of Biloxi or the school it’s self. We’re in Biloxi Ms. 39530. Does your company have records from that time ? 

We formed the company in 1986. In 1987 we did quite a few time capsules for places near us, in Southern California. Sorry, but we did not do yours.

I would normally recommend contacting the International Time Capsule Society in Oglethorpe, Georgia, but they did not form until 1990.

May I suggest reaching out to those who were janitors and food service workers (as well as teachers and secretaries) for the school, at the time? Best of luck!

We are celebrating the 150th anniversary of our community and considering the possible placement of a buried time capsule with the thought that it would not be opened for another 150 years. Are there boxes that can last that long or is it totally unreasonable to think that the contents would still be intact in any kind of container after 150 years? Thanks for your input on this. It will help us in our decision making. We don't want our descendants to find a "muddy mess."

We recommend the Bolted Time Capsule 3000 series. It has the best chance of surviving that long! It’s heavy duty, and designed to withstand quite a lot. The design also features a special sealing flange that will not permit moisture or air to penetrate through to the contents. Take care to prepare the ground correctly (not put it in a vault that holds water to the capsule) and seal the area above well, such as with a boulder or cemented area.

Please confirm what is length, width and height when your box measurement is 12x12x14”. Is the box lid 12x12 or is the box lid 12x14?

 For a Capped Time Capsule Box that is 12 x 12 x 14" of the 4200 series, the inner dimensions of the box are 12” Long x 12” Wide x 14” High. The dimensions are L x W x H with the last measurement being the height, so the inner box height would be 14".

Can you engrave the front (rather than the top) of the 12x12x14 Mars box? This will make it visible when placing the box into a wall recess. Look forward to hearing from you. 

No, sorry - our equipment prohibits this. We recommend it be placed on its side in this instance.

Looking to install a cylinder time capsule in the ground. What sizes are available?

 We have 4 sizes: 3.5" diam. x 11.75" H, 7.75" diam x 9" H, 5.5” diam x 22” H, and 6” diam x 24” H. Please see:

I am the Senior Class Advisor at a high school. As the students' class gift, they are raising money to purchase a time capsule to bury in one of the courtyards

.I have a few questions in regards to sizing and pricing. The Neptune box holds up to 525 items, what does that include? Envelopes, small objects, etc. Is there a way to lock in the current sale pricing? We are still in the process of raising funds and are unable to purchase the item at this time. Are there any additional available discounts for schools? That box may hold even more than that number of items if those items are small or skinny like papers and such. If you put uniforms in, that takes up more space (but is popular) or a stuffed toy (also popular). That one has plenty of space for you. Many schools have ordered that size with great success. But yes it does depend on what you put into it.As for the pricing, as long as that is in stock you are probably good for 30 days. If you'd like us to make an estimate for you, please send an email to us with your name, your school name and address and phone.

I have an interest in a time capsule plaque and viewed your website on the various ones available. How long from time order is placed to when it is ready to ship? Since it appears I need to place an order prior to getting the plaque designed, are there any charges associated with this design work? And please walk through this entire process. How many characters can fit on your 14 x 10 plaque? Cost to add our city logo?

If you only need the plaque, you should go straight to the plaques area. Here are the two areas.

If you know the text or writing you want on the plaque, you can just type it in the box provided on the order. If you have a logo for the plaque, you can upload the file there, too. We’ll help you with fitting it, or let you know if you need a larger size. When in doubt, before you order, we can take a look at your artwork if you email us with the question. We provide you with a black and white layout proof and a specifications sheet to approve, too. We also send along a pamphlet 

( . 

Any artwork should conform to the art requirements set forth by the foundry

 ( If it does not and you need further work done, we charge artwork by the hour, generally $75 minimum.

Other pages to see that may be of interest are: