Tuesday, April 10, 2018

Two Tables And Two Chairs

From "The Workbench Treasury Of Woodworking Projects" here are plans for two tables and two chairs. The first is a table inspired by Wendell Castles laminated work.

Below is an example of Mr. Castles work. Sadly Mr. Castle passed away in January. His design genius and beautiful workmanship will continue to inspire many for a very long time.

This one is quick and easy but has a lot of very solid appeal.

I find American Windsor chairs very appealing designs. Here are two originals with a write up and fully measured drawings. Nice examples of a classic.

Monday, April 9, 2018

10 Rules Of Pattern Design

Here is an article from another great mechanical design book "Mechanical Details For Product Design". This article deals with 10 basic rules of pattern design including shrink tables. Published in 1964, this is another book I would like to do some more future posts from.

Click image to expand, click again for best view.

Sunday, April 8, 2018

A Couple Of Teaser Puzzlers

So it looks like spring has passed us by, it's been snow or flurries and cold for a week now. I may have stepped through the wardrobe into permanent winter, (somebody kill the witch, the Turkish delight is a con, ha,ha lol).

So as mentioned in the previous post one of my favorite volumes on mechanical movements is "The How And Why Of Mechanical Movements". It was published by Popular Science in 1968 and written by Harry Walton. It is full of clear illustrations, but this is not just a book of pictures of mechanical movements. The book focuses on the science behind mechanical movements with clear explanations without getting overly technical. The illustrations focus on the concepts being communicated.

The book covers everything in mechanical development from the cave man to rocket development and how guidance systems work. I will upload the complete book in a series of posts sometime in the future. In the meantime here are some pictures and a couple of puzzlers to think about.

Click to expand, click again for best view.

Wow now I know why rocket science is "Rocket Science". Whats amazing is that they don't all blow up. Even the coolant used is fuel or 1000* gases. I guess my sometimes "good enough" attitude wouldn't hold mustard here, ha ha lol.

Here's a couple of little teasers that might get some thinking about how things work.

Tune in next week for the answers. Not really ha ha.

On The Subject Of Horse Power

Horse power is a subject often discussed and rarely agreed upon because of manufacturers different methods of rating their machinery. Here is an article from Amateur Work on the origins of the term and the basics of how the numbers were determined.

So continuing into the physics of power and horse power, here is an excellent write up from an excellent book "The How And Why Of Mechanical Movements" (see above post). Don't be scared away by the technical insinuation here, this book is another one of those great books I wish I would have discovered at a younger age. The explanations are clear without a lot of tech speak and lots of illustrations to help clear up the tech speak that there is, lol.

So why bother with a pony brake, why not just determine HP based on the stated current requirements. Because motors are not, and probably never will be 100% efficient. Friction, power factor, and the big one, wire resistance all contribute to lower available power at the shaft output. A 100% efficient 1.5 hp motor would draw 1119 watts, at 115 volts that equals 9.73 amps. However in real life a sealed 1.5 hp motor will draw + or - 15 amps depending on the manufacturer. At 115 volts this equals 1725 watts and an efficiency of 65%. Some open motors will draw as low as 13 amps indicating efficiencies of around 80% but for shop use, if you can, stick with sealed motors. Dusty conditions such as in the base of a bandsaw or other such application can produce enough fine dust to produce a dust explosion.

If superconductivity at room temperature can ever be developed in materials that can be used to build motors with, then 100% efficiency will be close. It certainly would be world changing, in everything from the electrical grid to the cellphone in your hand.

Friday, April 6, 2018

Amateur Work - Pattern Making

In 1904 and 1905 Amateur Work Magazine published a series of articles on pattern making for the amateur home hobbyist. The well illustrated articles cover the subject very well without getting too technical (industrial). The articles provide good instruction for the home hobbyist looking to cast his own creations.

To fill up the empty spaces, I inserted machine (I like lots of shiny handles, lol) and casting pictures from Canadian Machinery and Amateur Work volumes. I took some time to compile and clean up this 49 page file, I think it turned out nice. If you don't plan on doing any casting, but enjoy this type of subject matter, you will like this cleaned up file.

To download this file click Amateur Work - Pattern Making. 12 MB - pdf 

Busy Bee Pro-Staff Tips

So since Busy Bee's machines and logo are all over this article, it may look promotional, but beyond that, the information is informative and applies to shop machines of any brand.

I found this info on their site years ago, it may still be there but I have not seen it lately. The article does not focus on machines but rather on tips and techniques in there operation. I like the easy and accurate plan for making a 0 clearance table saw insert, and the machine mortise and tenons and dovetail jig operation are well documented.

Most hobby woodworkers will find something useful here, click Busy Bee Pro-Staff Tips to download the 36 page file. 651 KB - pdf

Thermit Welding

Most have probably heard of thermit, it was invented in 1893 and patented by Dr. Hans Goldschmidt in 1895. When the mixture is ignited the reaction will reach some very high temps, 4500* F is easy. So here is an interesting article from Amateur Work, published shortly after it came into commercial use, mainly for in place welding of rails and other heavy work, which at the time could not be done any other way.

Click to expand for best view.

Here are some pictures from the Wikipedia site. First a picture of an iron oxide mix. There are other mixes possible with other metals but a mix of iron oxide (rust) and aluminum powder will produce the highest temps. and most volatile reaction.

An iron oxide mix being ignited. It is often compared to black gun powder (but hotter I think).

Here, a rail joint is being welded. The pot assembly is clamped to the rail joint and the mix ignited, It quickly burns its way down to the joint depositing molten metal and welding the joint together. The pot is lined with a high temperature ceramic to withstand the heat. There is a good write up on the process in a Lindsay reprint, that I can't find right now.

A welded joint. Looks rough but when cleaned up is as strong as the rest of the rail.

Wednesday, April 4, 2018

Amateur Work - Projects 1

Amateur Work magazine was published early in the last century. It was published with the home hobbyist in mind and covered a wide variety of topics from electricity to mechanical engineering, woodwork and even boat building.

I found 5 volumes on the Internet Archive, vol. 1 to 6, # 2 is missing. There are 3 or 4 compilations that I want to make from them. I completed the first today, a compilation of the best projects in the first 2 volumes. I will make another with the other 3 volumes and there is a very nice series on pattern making and molding that I want to make a file with.

Took a little work but it cleaned up nice, click Amateur Work - Projects 1 to download. 9 MB - pdf

Thickness Sanders

So here is a small file I had (one of many) on thickness sanders. There are two larger units, one a larger version of the the one built by Shop Notes magazine and the other from an old Mother Earth magazine. The remaining ideas and information were from a model ship building site, that I am not sure exists anymore. There is lots of good information there on wood and sanding.

I have always looked at thickness sanders without a powered feed belt or feed rollers as a bit unsafe. If your not hanging on to the wood or slip your grip, the result could be rough. There is a good safety write up at the end of this file for limiting the chance of injury or damage when operating a thickness sander.

To download this file click Thickness Sanders. 1 MB - pdf

Tuesday, April 3, 2018

Small Project Collection

So here is a small project collection from one of my files. They come from various sources Model Engineer mag., Popular Science, a college site and others. Relatively easy to build and very useful in most small shops, wood or metal working.

The first is a knurling tool. Most of us have probably made an aluminum or other material, knob or handle, and would have liked to have knurled it for grip and decoration. This tool will let you do that with out the expense of owning a metal turning lathe.

Click images to expand.

This is probably the most difficult project in this little collection. This only because of the need to shape and bore the heavy 1" plate steel frame. The result is still one of the easier and better punch plans I have seen out there.

This little pin vise was on a school model engine building site. A very useful little tool for the model building hobbyist.

Can't remember if this was a Popular Mechanics or Popular Science plan, ha ha. In any case I have always found it interesting. In ash it will handle aluminum and light steel sheet, but I have always wondered how much more durable it would be in welded heavy steel.

So this is another drill press vise. You can build this one without castings and with care produce a vise that is more accurate than most.

Hope there is some appeal for these, I will share more in the future.