The angle from the cables to the new frame.
In the last post about the crane, “Using CAD in initial design – More work on the Popsicle Crane“, we determined all of the angles necessary to calculate the forces on all the beams and cables. In this post I will calculate all those forces
Continue reading Calculating the “Hinge Boom” on the crane.
The Base Drawing of the Crane.
People normally think of CAD drawings being used to produce finished plans. While that is probably the main use for drawings, CAD is very useful in all stages of design including conception and analysis. I have decided that I will do more work on the Popsicle Crane and
Continue reading Using CAD in initial design – More work on the Popsicle Crane
The crane boom.
Last night I tested the crane boom and the video has been published. The boom did a great job. The cables did not. I used paracord for the most stressed cables and it turns out that paracord is very elastic and I was not able to maintain the angle of the
Continue reading Test 2 of the Popsicle Crane Boom.
The Crane Boom is almost complete.
The crane boom is almost complete! I put off doing the most difficult part, the head or nose of it until last. The reason this part is the most difficult is it narrows in both directions. The base or butt assembly did not get any narrower across the
Continue reading Putting the Head on the Crane Boom.
The Plan for the Crane Butt.
Last night’s post, Popsicle Crane Update 3 was almost completely about construction of the crane boom hinge end (the “butt” end – a real term used by the crane industry.) I realized on the way to work today I did not talk about why I did what I
Continue reading Why I built the Crane Boom Hinge the way I did.
The Plan for the Butt of the Crane Boom
Much progress has been made on the construction of the popsicle stick crane. At the last crane update I had built built the major part of the boom and some pulleys. Since that time I have figured out how to make the pulleys spin fairly
Continue reading Popsicle Crane Update No. 3
A side view of the boom.
It has been a little bit since I have talked about the popsicle stick crane. Work is still proceeding but there is not a lot to show yet other than a few work in progress pictures.
I have built the main part of the boom and this time
Continue reading Popsicle Crane Update no 2
Rubber Columns just don’t get it done.
It this post I am going to try to tie together all of the recent posts about the forces on beams, moment of inertia, and the stress-strain curve. This is an overview and not number crunching like the last post. Since we are dealing with unknowns with
Continue reading Column Buckling – Length, Radius of Gyration, & Elasticity
Rubber Band simulation of a beam subjected to bending.
In the post “Stress, Strain and finding center“, I talked about simple compression and tension and how beam or column elongates under tension and shrinks under compression. In the elastic portion of the stress strain curve the beam is acting like a very very strong
Continue reading How a beam resists bending. (Moment of Inertia)
Several posts ago I talked about finding the center of mass of an object. That procedure when applied to a flat surface (a plane) is used to locate the point called the centroid. The the plane is a flat plate made completely from a uniform material, the centroid is where a pin could be
Continue reading The centroid (center) of a beam.