<p>The boxes from USPS are of consistently flat and relatively thin material, while the adhesive strip is also quite thin. As such, this material would not work well on coarser surfaces such as corrugated cardboard, especially as that material is not particularly flat.</p>

<p>Hot melt glue is thicker in general, certainly more fluid and able to spread and fill any surface irregularities. Using hot glue, you can get away with a relatively thin stripe that will flatten upon closure and provide substantial bonding.</p>

<p>You can purchase double sided tape of many types, from thin, paper-only bonding up to heavy duty carpet bonding tape. The latter would work quite well in the cardboard arena, as it is designed to bond irregular, not-particularly-flat surfaces, but it's also going to be more expensive.</p>

CC BY-SA 3.0
2018-04-11T03:20:40.347Z
+1. Is USPS flap’s adhesive material sufficient for frankenboxing 2 Priority Mailing Boxes with flat surfaces? Can I buy that in a bottle? USPS’s partial curing time until ready-to-ship for the folded-onto flap appears instant, though I guess it gets stronger over time in-transit. But is there a non-instant curing time at factory to anchor the adhesive to the pre-applied flap first so that the curing time for the folded-onto flap will be effectively instant? On flat-surface boxes, will USPS flap adhesive be stronger than hot glue?
CodeBricks
CC BY-SA 3.0
2018-04-11T09:31:28.350Z
If you're using USPS adhesive strips to bond one USPS box to another, you're likely to have good results on clean surfaces. It's tape, not liquid, however. It's a slightly resilient type of tape, that is somewhat "foamy" and does take more than an instant to bond, as you've noted. I believe that no selection of tape will be stronger than hot glue, based on experience.
fred_dot_u
CC BY-SA 3.0
2018-04-11T09:50:48.203Z
What is this tape or the closest thing on the market called?
CodeBricks
CC BY-SA 3.0
2018-04-11T15:44:43.217Z
Most of the double sided tape will be either thin and insufficient or extremely strong and expensive, typically for outdoor use. Curiously, there's a great middle ground: https://www.homedepot.com/p/hyStik-2-in-x-11-yds-Carpet-Paper-Double-Sided-Tape-890-2/204388994 which is 7 mil thick but designed to hold carpet which means it's also strong enough for your application. 48 mm width!
fred_dot_u
CC BY-SA 3.0
2018-04-11T00:37:40.797Z
2018-04-11T00:37:40.797Z
fred_dot_u
<p>I want to splice two cardboard shipping boxes to make a bigger shipping box. Is using hot-melt glue a fast, strong-holding, and cheap way? Which type should I use?</p>

<p>The pre-applied adhesive under the peel-able strip in USPS-produced Priority Mail boxes can be left unused at room temperature for years and still be effective. What is this material and is it better at splicing than hot glue?</p>

CC BY-SA 3.0
2018-04-11T13:03:28.903Z
While we do have expertise in adhesives, "a bigger shipping box" isn't really a traditional handicraft.
Erica
<adhesives><material-selection><material-identification><cardboard>
Effective adhesive material to splice cardboard shipping boxes?
CodeBricks
# Effective adhesive material to splice cardboard shipping boxes?

(Asked by: username_0 on 2018-04-10)

I want to splice two cardboard shipping boxes to make a bigger shipping box. Is using hot-melt glue a fast, strong-holding, and cheap way? Which type should I use?

The pre-applied adhesive under the peel-able strip in USPS-produced Priority Mail boxes can be left unused at room temperature for years and still be effective. What is this material and is it better at splicing than hot glue?

**Tags:** adhesives, material-selection, material-identification, cardboard

> **Comments:**
> **username_1**: While we do have expertise in adhesives, "a bigger shipping box" isn't really a traditional handicraft.  

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## 1 answers

### Answer by username_2 on 2018-04-11. Score: 1 | Accepted answer

The boxes from USPS are of consistently flat and relatively thin material, while the adhesive strip is also quite thin. As such, this material would not work well on coarser surfaces such as corrugated cardboard, especially as that material is not particularly flat.

Hot melt glue is thicker in general, certainly more fluid and able to spread and fill any surface irregularities. Using hot glue, you can get away with a relatively thin stripe that will flatten upon closure and provide substantial bonding.

You can purchase double sided tape of many types, from thin, paper-only bonding up to heavy duty carpet bonding tape. The latter would work quite well in the cardboard arena, as it is designed to bond irregular, not-particularly-flat surfaces, but it's also going to be more expensive.

> **Comments:**
> **username_0**: +1. Is USPS flap’s adhesive material sufficient for frankenboxing 2 Priority Mailing Boxes with flat surfaces? Can I buy that in a bottle? USPS’s partial curing time until ready-to-ship for the folded-onto flap appears instant, though I guess it gets stronger over time in-transit. But is there a non-instant curing time at factory to anchor the adhesive to the pre-applied flap first so that the curing time for the folded-onto flap will be effectively instant? On flat-surface boxes, will USPS flap adhesive be stronger than hot glue?  
> **username_2**: If you're using USPS adhesive strips to bond one USPS box to another, you're likely to have good results on clean surfaces. It's tape, not liquid, however. It's a slightly resilient type of tape, that is somewhat "foamy" and does take more than an instant to bond, as you've noted. I believe that no selection of tape will be stronger than hot glue, based on experience.  
> **username_0**: What is this tape or the closest thing on the market called?  
> **username_2**: Most of the double sided tape will be either thin and insufficient or extremely strong and expensive, typically for outdoor use. Curiously, there's a great middle ground: https://www.homedepot.com/p/hyStik-2-in-x-11-yds-Carpet-Paper-Double-Sided-Tape-890-2/204388994 which is 7 mil thick but designed to hold carpet which means it's also strong enough for your application. 48 mm width!  

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