For a science project I have to build a bridge made with popsicle sticks. The requirments are that the max number of popsicles is 200 and I can't modify any popsicle stick and I can only use elmers regular ol' school glue. I was considering a River Kwai Bridge design, but I want to see whay you guys can come up with (knowing railroad bridges are the best kind of bridge) - Peter
Modeling the Bellefonte Central Railroad
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Peter: A Kwai bridge will run a couple thousand sticks. How about a modified Bailey design? Give me an hour or so and I can give you a quick sketch.
I can sketch up some working plans for you to work from if you are interested.
Tom Trigg
Build the upper and lower "corbels". Start with 5 Popsicle sticks end to end. Take 4 more and stager them over the joints and glue. (see pic 1) Build three more of these. In my pictures I have dry stacked the sticks just to give you the idea.
After glue dries assemble the side panels. Two corbels spaced about 2/3 a stick apart. Start in the middle with a vertical "post" and then a diagonal brace, and work to each end. (pic 2). Play with the spacing between the corbels until you end up with a vertical post at each end.
After the side panels are dry add the "transoms". Glue them to the vertical posts of the panel. (pic 3) The transoms should extend beyond the edge of the panels by about an inch or so.
Once the glue dries for the transoms, then take the rest of your sticks and fill in from transom to transom for the "treadway" (deck of the bridge).Since I dry stacked everything for the pics, mine is not going to hold together but from the photo in my first response, I’m sure you get the idea.
From the "Bailey" design you can build either a "through truss" or a "deck truss". In pic 3 I am holding the transom in the lower position for a through truss, just move it up to the topside and you have a deck truss.
If your teacher asks about your design, you have based your bridge upon the "Bailey Bridge" used during World War 2 by the Allies. It was designed by a Brit. with the last name of Bailey. Do a google search for "Bailey Bridge" to gather some "sidebar" information to gather a few more "extra credit" points. The U.S. Army still has this bridge in its inventory and they are still painted "Royal Grey". When the Brits allowed us to manufacture their bridge they stipulated that it must be painted "Royal Grey" and we have kept our word. Now you have a "Science Project" with a "History Lesson". Good luck my friend.
It is always nice when You get someone else to do your homework.
ttrigg Build the upper and lower "corbels". Start with 5 Popsicle sticks end to end. Take 4 more and stager them over the joints and glue. (see pic 1) Build three more of these. In my pictures I have dry stacked the sticks just to give you the idea. After glue dries assemble the side panels. Two corbels spaced about 2/3 a stick apart. Start in the middle with a vertical "post" and then a diagonal brace, and work to each end. (pic 2). Play with the spacing between the corbels until you end up with a vertical post at each end. After the side panels are dry add the "transoms". Glue them to the vertical posts of the panel. (pic 3) The transoms should extend beyond the edge of the panels by about an inch or so. Once the glue dries for the transoms, then take the rest of your sticks and fill in from transom to transom for the "treadway" (deck of the bridge).Since I dry stacked everything for the pics, mine is not going to hold together but from the photo in my first response, I’m sure you get the idea. From the "Bailey" design you can build either a "through truss" or a "deck truss". In pic 3 I am holding the transom in the lower position for a through truss, just move it up to the topside and you have a deck truss. If your teacher asks about your design, you have based your bridge upon the "Bailey Bridge" used during World War 2 by the Allies. It was designed by a Brit. with the last name of Bailey. Do a google search for "Bailey Bridge" to gather some "sidebar" information to gather a few more "extra credit" points. The U.S. Army still has this bridge in its inventory and they are still painted "Royal Grey". When the Brits allowed us to manufacture their bridge they stipulated that it must be painted "Royal Grey" and we have kept our word. Now you have a "Science Project" with a "History Lesson". Good luck my friend.
Hey, do you mind if I could use your building methoods for a 1/6 scale bridge? I have always been a big fan of military hardware, perferring 1/6 scale because of the level of detail I can obtain.
What a minute, I am not asking anyone to do my homework, infact this is all in class work and I was looking for help with designs and I already have a basic design I made myself. - Peter
the North East Rail Modeler Hey, do you mind if I could use your building methods for a 1/6 scale bridge? I have always been a big fan of military hardware, preferring 1/6 scale because of the level of detail I can obtain.
Hey, do you mind if I could use your building methods for a 1/6 scale bridge? I have always been a big fan of military hardware, preferring 1/6 scale because of the level of detail I can obtain.
Don’t ask me, ask our British friends, after all, it is their bridge we’ve been using for the last 70+ years. It all goes to show the old axiom: build a better mousetrap and …………….. I doubt is they will object too much.
Peter: Just for the record, I had a young student several years ago build this bridge using craft sticks. He built the upper and lower beams of 5 laminations, "X" bracing instead of diagonal braces, and double posts. About 10 times the material you are allowed. His bridge spanned a 32-inch gap, and supported a 16-pound bowling ball for almost six hours before it failed.
Concrete canoes! You must be a civil engineer....yes?
I see the concrete canoes every tuesday as I go to my drafting class.
http://www.haworthengineering.com/
~Excellency in the Details ~
Concrete canoes! It’s been about 45 years since I played with one of those! We also played with "Resin Hard Cloth", I think you youngsters now call it "Fiberglass". I built my bridge from 75 pounds of toothpicks, and it held 60 pounds.
Concrete canoes! I'm only in 8th grade! And ttrigg, I want my bridge to beat the record holder for my team which is 189lbs. My science teacher said 100lbs is average. Any ideas on how to beat 189? I think with interlocking popsicles sticks on their sides like if you put your fingers together, like this:
,but with a solid bridge deck. I must leave a little hole in the middle of the deck so that the weight holder can be secured to my bridge. Also I think I might put some kind of truss since we are required to have a "gaurd rail." I think my minimum length is 52" and maximum is 56" my mininum width is 11"
You are in eight grade and you think the measurements are 52" x 56"x 11".
Who did you talk into reading the instructions.
Peter: Just a few hints, 1) you will get maximum strength from your "lumber" when is used widest dimension in the vertical (on edge). 2) You will want to put a slight arch upward on the roadbed so that when you run a string from one end to the other, your deck will be about half inch higher (pre-stressing the deck). 3) Your bridge substructure will be designed to provide tension pulling the two ends closer and shoving the middle up. 4) In the photo you posted (I take it that that is the record holder?) the substructure has two points where it shoves up to a single point of the bridge deck. I would rearrange so that the substructure push from a single point to two points on the bridge. This will increase the "tension" on the substructure and cause it to press upwards on the deck at two points. (In other words, "turn the "V" right side up, remove the "flat" of the lower trusses so that you end up with a very wide "V" pushing up on a more narrow "V" pushing up on the bridge deck. The wider "V" should/must be "interlocked" with the end of the bridge and itself at the very bottom. The narrower of the "V’s" should be braced in place with other "lumber" and not interlocked with either the deck or lower support.
Ttrigg-That is no the winner, but a very good bridge. I started my designing process yesterday and I am going to use a roadbed like the one above and now with your idea of a slight arch. I am going to have a truss with four cross frames near the center and possibly a few popsicle sticks layed across the road deck.
Spike- I am only know from what has been told. I missed a day of designing since I had a track meet. If your only going to criticize me then don't respond to this post anymore. I am only seeking the helpful advice of garden railroaders who have tons of expirence. I not letting them do my homework, I'm looking for helpful tips.
PJM20, my daughter was in high school and had to do a science project. I was flabbergasted when she built a rolling Schertzer bridge from a picture in one of my model railroad books. Good Luck on your bridge.
Heard a little saying about those that criticize, and I notice the resident criticizer in 'on' your case. His posts don't add much to other forums either.
Those that do, do.
Those that can't, teach.
Those that can neither do nor teach, criticize.
I expect you will do just fine if you pay more heed to those that can do or can teach and ignore the others
Art.
Peter: Knowledge is acquired from those with experience. It is up to you to put the experiences of others into practice and learn new and better ways of doing the same old tasks. It is up to you to pass on the new knowledge to those who follow along. I expect to see a few construction photographs as well as a photo of your bridge supporting the winning record weight.
Art,
Sage advice and well put.
Walt
To the North East Rail Modeler: Thank you so much for expressing so well my sentiments on this. My daughter wisely sought references at the library and near at hand and proceded from there. I think the same can be said of the OP.
This forum is a good place to research opinions, options, and methods. Taking the easier path or discovering what has been been done is not to be sneered at. Doing things the hard way instead of using near at hand references or procedures that have been tested and proved is, in my opinion, just plain dumb.
Art
I'd like to add just a little to this thread regarding the purpose of forums. The classic definition of a forum is a place for like-minded people to gather to openly discuss ideas and exchange information. I come to this and other forums for many reasons ..... to compare notes about some idea or project, to see what others are doing in order to get new ideas, to ask very direct questions about how to do something, to present my work or ideas and ask for constructive criticism, to offer my input if I happen to know the answer to someone's question, to name just a few.
What this young man has done is to attempt to use this forum for one or all of it's purposes as I have just listed, nothing more. Admittedly he could have posed his request for information a little more tactfully so that it seemed more a call for aid and less as a request for us to do the work for him. But he's young (I think he said he's in the eighth grade), he'll learn.
It's a shame that Mr. Spikejones 52002 feels that helping out this kid somehow takes something away from him, it doesn't, it's just all about passing on the knowledge. Perhaps he should consider not attending this or any other forum because sharing is what it's all about.
OK folks, let's all play nicely.
Well, my design has been approved by my teacher and I have started the building phase today. I have half of 2 sections for the road bed done. My road bed is the interlocking sticks I mentioned earlier. Each section has 23 sticks so far, but I need 35, so the building will go on. - Peter
My bridge is done, a little messy, but nice (I have too many track meets!) The bridge used a split road bed like in my photo and then I kind of reversed the supports and put more bracings. I will test on Wednesday, hopefully I get to a load of 200lbs before breaking. - Peter
Good luck on the test, but I sure don't like destructive testing. Keep your fingers crossed!
I don't like the destruction either, because I could use that bridge for my garden railway I am building this summer. - Peter
PJM20 My bridge is done,
I don't see no pix???????????
I'm sorry, but I don't have a cellphone to take a picture (yes, you heard me, a 14 year old with out a cellphone, I personanly think there are pointless) and I couldn't use a laptop to take a picture either since I barely finish with my alloted time. I'll try to get one on testing day! A warning now:not the prettist bridge, but I had track, but I hate rushing on projects like these, so ugly, but gets the job done. - Peter
PJM20I'm sorry, but I don't have a cellphone to take a picture (yes, you heard me, a 14 year old with out a cellphone, I personanly think there are pointless)
Well, PJM20 , you are not the only one. I don't have a cell phone that's officially "mine" and I won't have one untill I drive. I currently share one with my sister, but it is so rarely used, it's covered in at least 1/2-inch of dust.
Mabe I can build my own cell phone out of a CB radio After all, I have always wanted one for my truck
Don't fret about the cell phone. I didn't get one until I turned 74!
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