Category Archives: Construction

I regularly encounter interesting math, particularly geometry, in my woodworking and remodeling projects.

Screwed Wood Joint That is Totally Concealed

Posted on 12-November-2015 by mathscinotes

This is the first woodworking tool that I have seen that uses a two-part electric motor. I have encountered this type of two-part electric motor before in situations where some mechanical object needed to be rotated while contained in a completely sealed environment. In this case, the electric motor's armature has a screw thread that pulls the joint tight. See this web page for more details. I certainly can see several applications for this type of connection. Continue reading →

Posted in Construction | 2 Comments

Circular Saw Depth-Of-Cut Formula

Posted on 15-September-2015 by mathscinotes

I recently bought a battery powered, 6.5-inch diameter, circular saw from Milwaukee. I REALLY like this saw. I have been using it at my cabin in Northern Minnesota, a place where dragging around electrical cords is painful. This saw has quickly become one of my workhouse tools. Continue reading →

Posted in Construction, Geometry | 16 Comments

Lignum Vitae is a Remarkable Wood

Posted on 24-June-2015 by mathscinotes

I enjoy woodworking very much and I am now in the process of making a solid walnut countertop by gluing small walnut pieces together. While choosing the wood species for my countertop, I did consider a number of tropical species like teak and ipe. During this search, I heard a person mention that Lignum Vitae was the world's densest wood and is known for being so oily as to be considered self-lubricating. It is also a rare and potentially endangered species. Continue reading →

Posted in Construction | 1 Comment

Good Example of the Economy of Scale

Posted on 28-April-2015 by mathscinotes

Yesterday, I saw an interesting article in the Journal of Light Construction (JLC) that does an excellent job of showing how the per-square foot cost of a deck construction drops as the total area of the deck increases (Figure 1). I found this interesting because I am going to have a structure built on my lake property in northern Minnesota. I thought this data would provide a good illustration of how I use Mathcad generate product cost models. Continue reading →

Posted in Construction, Management | Comments Off on Good Example of the Economy of Scale

Candidate for the Dumbest Idea I Have Heard

Posted on 16-April-2015 by mathscinotes

My coworkers and I often discuss our home remodeling/repair adventures. This morning, a coworker described how a neighbor in his home town used a rifle to solve a common plumbing problem. I do not condone this approach and I am appalled at every possible level that someone would even try it. Continue reading →

Posted in Construction, Humor | 2 Comments

Geometric Table

Posted on 14-April-2015 by mathscinotes

I am always looking for interesting construction projects. I don't necessarily plan to build them for myself, but I do often turn to these project for inspiration. I usually store them on Pinterest. Continue reading →

Posted in Construction | Comments Off on Geometric Table

A Little Geometry for Laying Out a Drawer Pull

Posted on 3-March-2015 by mathscinotes

I finished building a cabinet a couple of months ago just as the extreme cold arrived, which made my garage shop uninhabitable.. The ten-day forecast is now showing rising temperatures, so I am starting to think about my next cabinet construction effort. Continue reading →

Posted in Construction | 2 Comments

Fan Airflow Versus Static Pressure Diagram

Posted on 19-February-2015 by mathscinotes

I was so happy with my previous fan installation that I am considering replacing some old fans with new, higher throughput, and quieter fans. The installations will be similar to that shown in Figure 1.

I have been using a nomograph (Figure 2) for my home HVAC calculations (example). I have decided that I am now living in the 21st century and I should figure out the formula that this graph represents. In this post, I will generate part of this nomograph to verify that I have put together the correct formula. Continue reading →

Posted in Construction, General Science | 3 Comments

Bathroom Fan Selection

Posted on 1-February-2015 by mathscinotes

I recently began remodeling a small bathroom on the second floor of my home. I have never been happy with the ventilation in that bathroom, particularly during showers when it seems more like a steam room than a bathroom. I decided to upgrade the ventilation fan in this room and I have been very happy with the improved performance. Figure 1 shows how the fan looks on my ceiling − yes, I am experimenting with a wood ceiling . In this post, I will go through my fan selection process and my ultimate choice. Continue reading →

Posted in Construction | 4 Comments

PVC Expansion and How to Deal with it

Posted on 27-January-2015 by mathscinotes

I have written a post about the problems that I encounter with the improper use of PVC pipes and accessories in outdoor Fiber-To-The-Home (FTTH) deployments. During my normal reading about codes and regulations, I found an example of a bad installation and an example of how to properly deal with PVC expansion by installing an expansion joint. Both of these items deserve some coverage here. Continue reading →

Posted in Construction | Comments Off on PVC Expansion and How to Deal with it