In Loving Memory of Simone Gauthier,
August 26th, 1915 - February 18th, 2008

Thursday, April 16, 2009

Match Stick Trestle, a test of strength

Since I intend to someday start building trestles in G scale (and maybe O if there is a call for it) I wanted some hint of how sturdy trestles are.

The one in the photos is built out of match-sticks and white all-purpose Elmer's glue. The trestle was not built to any specific scale, but does loosely follow plans found on the internet. It was built solely for the purpose of piling measurable weight on it until it was crushed.

I don't have pictures of construction, I didn't think of it. I also don't have pictures of many of the small tests that I did.

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Pictured with an U.S. Quarter (round circular blur laying on top).

I started out thinking that it wouldn't take much to crush it, figuring that the glued joints would fail quickly. I put the section on my mother-in-law's diet scale, which was capable of 2 pounds. Being only interested at the weight at which the trestle gave out, I did not keep any results as I added circular steel scraps that I got from my Dad. I do not know how much each weighed. I was able to pile all of them on without affecting the trestle.

I got ballsy and decided to skip ahead (bad practice, I know) and placed the section on the flat kitchen counter and used a cutting board on top of it for a flat surface on which to balance a 3 litre bottle of soda-pop. Based on water weighing 8 pounds per gallon, 3 liters = .792 gallons , therefor 3 liters of water = 6.6 pounds. This amount of weight also had no affect on the trestle.

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Close up of 6.6 pound, 3-litre bottle on trestle.

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Mid-length shot of soda bottle on trestle.

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Long Shot of bottle on trestle, showing the weight being taken ONLY by the trestle. Getting this to balance was a task in itself!

Once I had proven at least 6 pounds, I skipped ahead even farther, and took the section outside to the front porch. I placed the section on the railing and balanced a 26.5 pound cement block atop of it. Unbelievably, this also did not seem to affect the trestle. I snapped a picture or two but my arms were not long enough for me to show that the entire weight of the block was being supported by the trestle and that I was only providing balance.

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The only useful shot I was able to get of the cement block.

When I tried to maneuver myself to show that nothing other than the trestle section was supporting the entire weight of the block, I inadvertently produced a small amount of lateral twist which resulted in a catastrophic failure of the structure. In layman's terms, I squished it. NO, you sadistic pest, I do NOT have pictures of the aftermath!

I can't wait to build a trestle in G or O scale out of Western Red Cedar. The timbers will be 1/2" square and significantly stronger than the matches..

I eventually intend to build one out of bamboo skewers too, for the sake of crushing in another strength test.. When the time comes, I will post photos.

Till then, I hope you enjoy this batch!

Mike.

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