1. Humidity affects the weight of your bridge. Keep your bridge in a closed container with a few grains of rice.
2. Go easy with the glue bottle. As a general rule of thumb, if you can see it than you are using too much.
3. Keep your hands clean! Oils and grease from your skin [...]
Now you can download the 5 Steps to Building a Model Bridge PDF ebook. The ebook contains the expanded version of the outline below, plus a lot of helpful pictures. The ebook also contains 25 bonus tips.
#1: Know the rules!
Be able to define in your own words what the bridge must accomplish
#2: Design the bridge
“Center” [...]
The concept of stiffness is one I have been delving into this year. The stiffness of the wood you use directly translates into the strength of your bridge. Density no longer matters much, and is almost not worth calculating unless you can find a relationship between density and stiffness. I have not been able to [...]
Balsa wood is unique from all other woods. Its properties make it valuable to bridge builders, wood carvers, surfers, and many others.
To learn more about the physical properties Balsa, see these articles:
Characteristics of Balsa Wood
What Is Balsa Wood
Balsa wood Grain
My favorite article about Balsa wood was taken down, but I found a copy of it [...]
I am very excited to show off this new digital gram scale I ordered off Ebay.
This digital scale measures to 0.01 grams, which is a major improvement over the team scale, which only measures to 0.1 grams.
The best part is that it only cost $20, shipping included. A hot deal if you ask me.
It seems [...]
The type of joint you use on your bridge can drastically change its strength.
Lap Joint:
The lap joint is one of the strongest, and you should use it whenever you can. It strengthens compression members because it adds stiffness. The lap joint has one drawback, however. The joint is only as strong as the face of [...]
What you want to look for in glue:
Drying time
Price
Weight
Strength
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 [...]
There are several reasons you should cut your own strips of wood:
It saves money
It saves time
Helps you get familiar with the wood
Increases your skills as a builder
Video Tutorial
Video is about 4 minutes long.
DISCLAIMER:
I am not responsible for any injury caused by someone using this technique. I recommend that students cut strips of wood [...]
I was looking at my logs this morning, and noticed someone found my website by clicking a link from a Yahoo answers page.
Curious, I went to the page. Someone was asking how to build a Popsicle Bridge. Two people had answered the question. The first person mentioned my website along with a complimentary description about [...]
An L-beam is more efficient than a square the same width. It is not going to hold as much, but it is going to be more efficient. An L-beam is also more efficient than a square with the same mass of wood. Of course, you have to count in the glue weight for an L-beam.
Balsa, [...]
I think it is time for me to build a popsicle stick house. I have built plenty of popsicle bridges, and even a popsicle boat. This collection would not be complete without a popsicle house.
I think I am going to stay simple with the design of the house. No fancy roofs or windows. Perhaps I [...]
I have built three different models of popsicle bridges. You can check out each one:
Popsicle Bridge #1
Popsicle Bridge #2
Popsicle Bridge #3
Popsicle bridges provide a unique challenge because of the limited length of the popsicle sticks. This hurts the inherent strength especially in tension. Ideally, a member of the bridge in tension would be one [...]
Not all popsicle sticks are equal
If you have been given a project of building a popsicle stick bridge, there is something you should know. Probably one half of the popsicle sticks that come from Wal-Mart or other store are bent, twisted, or otherwise deformed. And obviously deformed popsicle sticks won’t be as strong as straight [...]
Objective: To build a boomilever with the greatest efficiency.
Basic Design:
There are two basic types of boomilevers. First is the tension boomilever, where the tension chord is longer than the compression chord.
Second there is the compression boomilever, which is the opposite of the tension.
It is generally accepted that the tension boomilever is inherently better than the [...]
My first event was Circuit Lab, which I don’t know much about. My partner ended up doing most of the work, I helped connecting wires when I could.
Rocks and Minerals went okay, or so I thought. Ended up with 7th.
My tower broke too soon, weighing 6.5 and only holding 6.8kg. At least I worried McIntosh [...]
I have developed a system for bending wood for my arch bridges, and though I do not claim it is the best way, it works well for me.
I have a pot, or basin rather, that is about 18″ long and 12″ deep. I fill it with about two cups of water (I have found that [...]
There are several ways to test model bridges:
With a machine
By pouring sand
Textbooks
Pushing down on your bridge
Using a machine
Obviously, if a machine is being used to test your bridge, there isn’t a lot you can do. You can stand watching the destruction of your bridge. Or turn away and cover your eyes with your hands. I [...]
I am constantly asked whether balsa is better than basswood. Here are some of my notes comparing the two woods.
Balsa is cheaper and more available than basswood.
This means you can buy more wood, and build more bridges for the same amount of money. By building more, you will gain valuable experience and improve your skills. [...]