Choosing the Right Glue

The glue you choose to use on your model bridge (or model airplane) can make or break your structure. I’d venture to say that glue choice is just as important as your wood choice, which makes it pretty important. If you build your bridge with a weak glue, then no matter how good the design is your bridge will not perform well. This article compares and contrasts different types of glues, showing the strengths and weaknesses of each so that you can make an informed choice for what glue to use on your bridge.

What you want to look for in glue:

  • Drying time
  • Price
  • Weight
  • Strength
  • Ease of Use

CA Glue
This is a very common glue used for a variety of projects. It dries in seconds, like super glue. It is also widely available. Numbers of hobby stores and online companies sell it. However, it is not cheap. CA glue can be bought in three types: thin, medium, and thick. The thin stuff is very light, but not especially strong. The thicker stuff is heavier, but stronger. I have known people to build extremely efficient bridges using CA glue. I do know that I will never use regular super glue after seeing how much better CA glue is. Purchase Pro CA Glue 1/2 oz Thin

Elmer’s Carpenter Wood Glue
This wood glue is very well known and well used. Elmer’s makes a solid glue, although I see it as on the heavy side. If you want to go with a good glue, then this is a good choice. Remember that with wood glue, you can actually get a stronger joint by adding a little bit of water to the glue. This allows the glue to seep into the wood, creating a stronger joint. Buy Carpenters Wood Glue by Elmers from Amazon

White Elmer’s glue
This glue can be bought anywhere, and is relatively cheap. It usually dries in 30 minutes, which is somewhat long for building bridges. Also, it is not very light or strong. I have come to the conclusion that white Elmer’s glue is not a good choice for model bridge building. Buy Elmer’s White Glue

Titebond Wood Glue
This glue bonds balsa wood very well. It also can be found in most hardware stores. However, it is fairly heavy. Many people mix water with the glue to cut down on weight. It dries fairly quickly, less than 10 minutes in small amounts. Elmer’s wood glue also provides a strong joint. The reason I don’t use this glue is because I don’t think that it is the best. But it is still pretty good. Titebond III Ultimate Wood Glue, 8-Ounces

Epoxy. The first glue I ever used in building model bridges was 30-minute epoxy. I liked it because it was very strong and could be bought at many stores. Epoxy comes in several different “setting times”. You can get 90 second, 5 minute, 15 minute, 30 minute, and up to 4 hour epoxy. The bad thing about epoxy is that you have to mix it. I had trouble mixing it correctly in small amounts. I ended up wasting a lot of glue mixing a lot of it at once. Also, epoxy is not very light. An interesting feature about epoxy, it heats up when curing. Sometimes it can get quite hot. Purchase PermaPoxy 5 Minute General Purpose Epoxy

Special Glues:

This is polyurethane based glue and is super strong. It is a cousin of Gorilla glue. It is not light, but you don’t have to use very much of it. However, the only place I know of that sells it is a local Ace Hardware store. It is also very expensive, which is why I don’t use it much anymore. It takes at least 4 hours to set, which is a really long time to wait. I still keep a bottle of it on hand, because it works for about anything. Elmer’s Probond Wood Glue 16-Ounce

This is the glue I have switched to, after seeing it at good ol’ Ace. It is lighter than Probond, almost as strong, and a whole lot cheaper. It looks a lot like white Elmer’s glue, but dries completely clear. It sets in no more than 30 minutes, but often in less than 10. Weldbond Universal Glue 4 oz Bottle

If the type of glue you use is not listed, shoot me a message.

Chart Comparing Glues

  Wood Glues CA Glue Probond Weldbond Epoxy White Elmer’s
Strength 3/5 4/5 5/5 4/5 4/5 2/5
Price 3/5 2/5 2/5 5/5 3/5 5/5
Weight 3/5 5/5 2/5 4/5 2/5 3/5
Drying Time 3/5 5/5 2/5 4/5 2/5 3/5
Ease of Use 4/5 3/5 3/5 4/5 2/5 5/5
Average 3.2/5 3.8/5 2.8/5 4.2/5 2.6/5 3.6/5

Obviously this chart is biased to my own experience with these glues. Please share your thoughts and experiences by leaving a comment.

Additional Resources:

54 thoughts on “Choosing the Right Glue”

    • Shawn, I haven’t used Gorilla glue much, especially not the variations of it. My initial impressions were that it seemed very similar to Probond, which is mentioned here.

  1. Garrett,

    I have an upcoming balsa bridge competition that has a time limit and is judged on efficiency according to its maximum load. From this page I would assume CA glue is my best bet. What is your opinion?

  2. I have seen some people use hot glue on their pop-sickle stick bridges online. In my experience, it snaps really easy. What sound appealing is drying time and cost. If everyone in the class is required to use hot glue would it still be a good learning experience or the lack of bond would make the project a bit of a waste of time?

  3. I am repairing my grandmothers 50 yr old popsicle stick lamp. Your information has helped me. I wish i knew the glue she used because it is so stronge. Just a few areas have come loose and the rest are still very tight. I plan to try some of these. I started off using the carpenters wood glue. if this doesn’t work I’ll try one of these others. Thank you

  4. Hello,

    I was searching for glues in my area but I wanted to find weldbond but when i was searching the staff suggested me to use JB weld I searched for it but there are many types which should I use?

    Thank you

    • I am Geometry teacher. Each year my students build bridges and we have used many different types of glue. I have found that Locktite professional super glue works the fastest and best. It drys within seconds and the sticks will break before the glue joint. Students have tried Gorilla glue and its OK but not as good as Locktite.

  5. Garret,

    I am doing a project where we are trying to do the most efficent maximum load/weight of bridge. Out of the glues that you listed above, which one do you think would be best for strength/weight of glue?

    Thanks in advance for your help!!


  6. Garrett,
    I’m planning a Pratt pin-truss bridge for an S-scale model railroad module for our club layout. It wil be 30″ long and approx. 6″ x 6″ cross section with 6 5″ bridge segments. It has to support as much as 50 lb. Assuming one heavy articulated locomotive on each of the two tracks. These locomotive cost over $1000 each, so my bridge has to be strong enough. My plan is to hide 4 ea. 30″ by 1/2″ x 1/8″ steel strips in the horizontal stringers under the rails and use 1/8″ marine plywood for the main uprights at the ends and first vertical sections. All of my diagonal and lower center horizontal tension members will be 1/16″ x 1/4″ aluminum strips. My pins will be steel 1/8″ diameter. Can I get away with basswood and plastic for the rest of the compression members? I really like the light weight appearance of the pin-truss design but I’m not an engineer and i don’t want to risk a failure. Fortunately the load will be distributed, but also dynamic. Thanks in advance for your advice. Steve

    • Steve,

      This sounds like a really fun project.

      I think I get the picture of most of your design, except for the “first vertical sections” being 1/8″ plywood.

      Are you going with a Pony truss (open top)? What about your top chords, what material/dimensions are they?

      Why not just use aluminum strips for all the compression members? I am a little concerned if you had a 1/4″ square basswood strip for the compression member, but drilled a 1/8″ pin through it.

      Have you tried plugging your design into the Johns Hopkins designer? I’d be curious exactly what the load on your compression truss members is based on your max load. 50lbs isn’t all that much over a 30″ span, so you are probably going to be safe with Basswood. As far as using plastic, I don’t have experience with it, and it probably depends on the type of plastic.

      When you’re done, send in some photos!

  7. i have to do an outline for science about making wooden bridges. this really helped and will help making the glue decision easier! thanks


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