Author: Aaron

Restocking my grandfathers tool chest

Post author By Aaron
Post date February 19, 2010
No Comments on Restocking my grandfathers tool chest

So one of the projects that has gotten starved for time lately is working on my grandfathers tool box. My father was, among other things, a carpenter. He worked pretty much right up until he went into the hospital and unfortunately the tools he had at his last job site were “lost”. So when my father recently gave me all of my grandfathers tools that he had it was an interesting collection. The centerpiece of which was two of my grandfathers old toolboxes – including his large carpenters tool box.

Largely empty of tools – the toolbox still had the original wooden dividers my grandfather had made and was filled with an odd assortment of tools (e.g. braces, bits, a crow bar). Now that my dad is retired he also gave me some of his tools and I decided to make new dividers combined with the tools I had gotten from my father re-stock the toolbox.

After taking the dividers in and out of the tool box a dozen times to confirm fit after each modification I decided to make a scale cardboard version of the sides of the toolbox so I could work on the toolbox like one of the sides was removed. Below you can see the tools lid out for test fitting.

In case you are wondering why it is so much work to just stuff a tool box – maybe it would help to understand the requirements. The toolbox is 32 inches by 9 inches and eleven inches tall at its peak. The top is angled so it is not quite as large as that would make it sound. My goal is to be able to pick the toolbox up and comfortably carry it with one hand. So I am putting an absolute limit of 50lbs on its weight when full of tools. I would also like to be able to get at commonly used items without having to move another tool, or at worst having only to move one other tool.

Here is what I have in the toolbox so far…

2 pannel saws – one cross cut and one rip
Backsaw – dovetail saw filed crosscut
A hacksaw
A coping saw
A pad saw
Crowbar
Cats paw (small pyrbar)
Tiny cats paw
Try square
Speed square
Adjustable square
Framing square (leg of which sticks up out of box)
Large razor blade knife (with extra blades)
Several small razorblade pen knives (with extra blades)
Marking knife (for dovetails)
Carpenters pencils
Folding carpenters ruler
Tape measure
12 inch steel – cork backed ruler
Zippo lighter
Pencils
Notepad
Calculator
Plum-bob
Needle files
Level
Wallet for extra plane blades and extra blades for the different planes
2 1” chisels and 1 1/4 inch “beater” chisel
Angled marking gauge
Combination spoke-shave (round and flat)
Sharpening honing stone
Small bottle of honing oil
Hand scrapers in leather envelope
Small bull nose plane

That sounds like a lot but the crowbar and cats paws go in the small saw till at the back of the box, and the right front half of the box forms an open tool well that got filled with specialty holders. So things can get packed fairly tight and yet be easy to get out without tools banging together.

I still need to finish holders but I know where the following tools will go in the box

Diamond needle files
Collection of dentil picks
Assortment of small sandpaper squares
Telescoping mirror
Telescoping magnet
String level
Plastic impact mallet (for chisels, and “persuading” things)
Hammer
Low angle Jack plane
Skew block plane
Small Rabbet plane
Screwdriver for plane adjustment
Tiny brass hammer for blade adjustment
A Stanley 60 1/2 adjustable mouth block plane
Needle nose pliers
Lineman’s “dikes”
Small wire cutters
Locking pliers
Chalk snap-line

Even with all that there is still some room to work with. My problem is that I still need to pack in the rest of these tools / items.

Torpedo level
Small hand mirror
Several neodymium magnets
Several 1 and 3 inch C clamps
String for line level and plumb bob.
Several bevel edge socket chisels for dovetails
Extra blades for coping saw and hack saw
Glass cutter
Push drill and bits
Set of good screwdrivers
Earplugs
Eye protection
Rag
Leather work gloves
Small thing of super glue
Needles and thread
Simple first aid – band aids, antiseptic cream, ibuprofen packet

My main problem, I think, will be figuring out how to get the screwdrivers in the right side tool well – and easily accessible – without making it hard to access they other tools.

Below you can see me laying out my planes. They will sit in a small wooden pull out drawer. The pulls out portions are going to be made from cherry – while inside the box I am using mostly poplar and a decent grade of plywood.

The planes above are a Lie-Nielsen sckew block plane, low angled jack plane, and rabbet plane. The jack is amazing in that it can be set for rough or finishing work. I have a spare blade for it and also got a 90 degree scraper blade to be able to use it for finishing. The skew block plane is useful for both a block plane or for use in dadoes. I have a set of side rabbet planes and a place reserved for them – but I am still on the fence about adding them.

Here you can see the left side of the box. There is a small well area on the bottom of the box. That is where the oil-stone and plumb bob will live. This is where I am thinking the chalk snap line will go. Along the side of the space is a pocket for the scrapers and a bin for pencils and pens. The reason there is about a quarter inch of dead space along the side of the toolbox is that is where one leg of the large framing square sits when in the box. It is a bit of a hack but I plan on sewing an envelope to hold an assortment of pieces of sand paper. That envelope will sit on top of the carpenters square in this dead space.

The drawer with the plane box sits atop the left side storage well. I should also be able to have another box atop that and then room for a smaller pull out tool drawer at the top of the box. The layout was bugging me so I went and made a cardboard mockup of that top drawer. That way I can build it and the plane drawer and then make the center box to fit. Not quite optimal but I am fairly sure I will be able to fit the chisels I want – as well as the sewing kid and some other tools in those center boxes.

Cardboard prototype of left side top lift out tool drawer

Here is what the right side tool well looks like – if the back of the toolbox were removed. This has proved the most useful attribute of the cardboard mockups of the box’s sides – being able to visualize the insides as if I had x-ray vision. It is kind of like making simple test cases when developing software.

So I am currently laying out a small set of holders to go next to the chisels, but on the other side of the coping saw. Should look something like the picture below. I am still trying to figure out if I want to have dividers between the tools. On the one hand it would keep the tools from rattling around but it would mean I would have to have *those* tools and could not swap tools in and out as needed. Still on the fence about how to do this.

Planning layout for new tool well in right side tool well

Logic

Word elimination problems

Post author By Aaron
Post date February 11, 2010
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I am a moron. Yup. I sat down and worked a 4×4 problem this morning only to prove it was impossible to solve. It helps if you copy the problem down correctly. Normally I am fairly anal about this type of error but I was writing out a detailed description of how to solve the problem and it spilled onto a second page. When copying over the current part of the problem… whoops. So I worked the next problem in the book, this simpler 3×3 of the same type, and will only post one today. After all I need to get to work from the morning coffee break!

Ok, so while I like the reasoning this type of problem encourages – I don’t like it when the longer ones assume a thorough knowledge of English. Mostly, I don’t like relying on the English vocabulary because English has a loosely defined vocabulary that borrows words from all sorts of other languages. Working one of these problems I found several alternate answers with words I considered English but which were borrowed from other languages. I think I will also avoid them as students who do not have English as their first language would be discouraged from solving the problems.

The problem says you are looking for a 3 letter word. You are given four words. The first, HAS, has zero letters in the same location as the word you are looking for, the second and third words, CON and CAB, each have one match and finally the last word SON has two matches. What is the word you are looking for?

I think I will work the problems I find like this as they are – but then change the letters to combinations of symbols and colors when making new problems along these lines.

Logic

“Added Corners”

This is another problem that is really simple to introduce but I could quickly make much harder providing problems that reward the reader / student for being clever – punishing brute force attacks.

Right off the bat I am thinking this problem going from a square to a cube – or other three dimensional shapes – so the user has to be doing both reasoning and mapping to spatial objects.

The problem is:

Logic

“Segments”

This type of problem might be good to reward the reader / student for clever and not brute force attacks. This problem is simple enough to brute force through it but add in a few extra digits and more rules would stop that. So I can use one like this as an example then grow the string to make the problems harder. I also think this problem would be better with crossed patterns – sort of like numeric scrabble. I think I have seen math puzzle books in the airports with patterns like this. Probably something like what they are doing.

Any way – the problems it:

Algrebra

“Twin statistics”

Ok, this is another problem that was kind of lame as worded but could be turned into a useful example

Problem as stated: Suppose that 3% of births give rise to twins. What percentage of the population is a twin 3%, less than 3%, or more that 3%.

So the problem is obviously trying to get the reader to realize the birth of twins increases the population by two people as opposed to “normal” births increasing the population by a single person. Then intuit what that means to the percentage of twins in the population.

No reason that the reader should not be able work out the exact percentage given the problem as stated and the assumption that triplets, quintuplets, and all other multiple births are a negligibly small percentage of the population.

Stated this way I can use this problem to introduce readers to the idea of taking two equations dependent on some third and unknown variable that cancels out later.

Logic

Which twin am I talking to?

Post author By Aaron
Post date February 9, 2010
No Comments on Which twin am I talking to?

Ok, super simple problem, but it would be good as an example for introducing people to truth tables at the start of a section with a bunch of the “liar” problems.

Problem #1 page 6 of hard-to-solve brainteasers

Problem: Peter and Paul are twins. One of them, we don’t know which, always lies. The other always tells the truth. I ask one of them “Is Paul the one that lies?” and he answers “Yes”. Was I speaking to Peter or Paul?

Logic

“Prohibited Connection”

Bought a copy of “Hart-to-solve brainteasers over the weekend. So far that title has been a disappointment – most of the problems assume that the reader has not had any formal training in problem solving – so the hard parts of finding a solution seem to be reinventing the tools needed to tackle the problems. Especially, annoying since the answers section just list answers without telling the reader how to solve the problems. Defiantly something I am going to have to keep in mind if I go through with writing a puzzle book.

This was problem #19 on page 12 of that book:

Using numbers 1,2,3,4,5, and 6 put each of the numbers in a circle with the constraint that no circles connected by a line can contain adjacent numbers. For example the circle with a three in it cannot be connected to either a circle with a two or a four.

Projects Woodworking

My “new” leg vise!

I was having a crappy day yesterday and the best prescription for that is always to check something off of my to-do list. My leg vise had been sitting half finished on the corner of my workbench bugging me so it seemed the job. I drilled the vise jaws and attached the screw from a cheap grizzly workbench.

I was looking forward to having the vise but it is a huge improvement over the other vise on my bench. Kind of odd since it is the same screw mechanism. I might have mounted the screw a little too low but I am very happy with it. I really should take some time and clean up the look of the leg. As this was my first leg vise I was just shooting for functional – but since I get the feeling I will be using it a lot I should probably go back and clean up how it looks.

Puzzles Tiling

Simple tiling problem

This makes for a nice problem in tiling. At first glance it looks hard to solve – but you the solution is obvious seconds after you start formally trying to solve the problem. Put this as an example early in the chapter on tiling and segmentation problems to help motivate readers.

Book Notes

Deduction problems….

So some nut jobs out there on the web have published a puzzle they claim Einstein authored. They also claim only 2% of people who try the problem will solve it.

Since it is a fairly straightforward problem to solve if you have any training I very much doubt both claims. I know for a fact that anyone who has passed a college level freshman chemistry course or digital circuit design course would have the tools to solve this type of problem.

They are an enjoyable type of problem though. I will be posting my write-up with solution to the problem in the next day or so. I have been thinking of how to make this type of problem for a book and that got me to thinking about making one that is harder and easier.

The idea: Noah’s Ark.

Problem One: Noah has to get the last N animal pairs packed into the remaining N cages on the ark so he can close up before the flood hits. He knows things about the animals such as

Types A can not be next to type B or they will eat eachother

Problem is fairly simple to make it harder add

Constraints where there are M cages and N animals pairs with M<N so Noah has to pack some animals together.

Problem is fairly simple to make it harder add

Size information on animal size so a small and a medium animal can be in the same cage, or three small animals can fit in one cage. This combined with predator problems can be set to make the problems more complex to tackle, but still solvable with the same tools.

Problem to make it harder add

Size information known about some of the types, and position of some of the

Cages e.g. large tall cage is next to two short cages.

Adds another dimension of constraint variables making the problem potentially much harder. Also makes the graphing tools used to solve it a little less intuitive.

Figure I can give 3-4 variations on the Ark problem to teach different approaches to solving deduction problems.