Saturday, October 25, 2008

Tool Kit to Go

I've been going through the digital pictures on our computer, trying to figure out just what all is in there, and I came across some pictures of a kit of tools. I had taken the shots so I would remember what was included in the kit, and then promptly forgot about the pictures and the kit. I guess this would qualify as a "Desert Island tool kit", only in this case it was "Alaskan Wilderness tool kit."

Two summers ago, my brothers and I were planning a raft trip down the Nelchina River, onto Tazlina Lake, and down the Tazlina River.

Here’s a Google Map of the area:

View Larger Map

Part of our plan involved building some kind of mast from driftwood or downed timber, and rigging a sail (blue tarp) to take advantage of the prevailing wind on the lake. To this end, I put together a tool kit that would be as versatile and as small as possible.

Unfortunately, events conspired to keep me from going on the trip, but the tool kit went without me.

Here’s the kit I put together for the trip:

Utility Knife
Sharpening Stone
Auger Bits (5)
¼” hex driver for brace
Flat and Phillips hex bits (3)
Various Screws
Vise Grips
Adjustable Wrench
Sven Saw (not pictured)
Rope (not pictured)
Ubiquitous Blue Tarp (not pictured)
Dry Bag (not pictured)

It all conveniently fit in the shop apron that I no longer wore...

...which then folded up into a perfect package to fit snugly into a small dry bag for the trip.

It was a fun challenge to put the kit together - trying to keep it as simple as possible tool wise, but as complex as possible capability wise. And of course, it would have been better if I had actually gotten to use it...maybe next time.

A few random notes:

The blue thing on the drawknife is part of a plastic document binder - it snaps on to the blade and protects fingers that wander through the gap in the folded handles.

The film canisters (hey - remember film?) contain an assortment of screws and nails.

The Vise Grips and wrench were specifically taken for working on the raft frame.

The mast was designed to be lashed together.

Sunday, October 19, 2008

Removing Rust With Electrolysis

**NOTE: While my shop is pretty much electron free woodworking, this post is all about using electrons directly. Ironic, no?**

I was telling a friend and co-worker about my experiences using electrolysis to remove rust from tools and thought it might be time for a post on this subject.

But before I get started let's just clarify a few things:

1. I am NOT claiming to be an expert on this, but I have had quite a bit of success with this method. Most of this I learned on the Internet - but as far as I know, the "CAT Scan" set-up is my own idea.

2. Be careful - this does involve electricity and water and it gives off hydrogen and oxygen gas. I recommend doing this outside. (Which in Alaska, makes it a summertime only activity, so obviously these pictures are not current - actually, judging from the shop in the background, they are even older than I remembered!)

Okay, let's get started. For this example we will be using a Stanley #65 low angle block plane. Here's the before and after shot:

I probably should have taken pictures of a more dramatic de-rusting. This tool was not too bad to start, and I could have simply went at it with some steel wool or sandpaper. But, the difference is that with electrolysis, you don't hurt the tool at all. No abrasion, no lost of metal (pitting will still be there however). It is a little like magic when you wipe it off after its bath.

You'll need:

Rusty tool
Sacrificial iron or steel
Car battery charger with ammeter
Assortment of alligator clips/leads
Non-metallic tub
Washing Soda (Baking Soda works too, just not as well)

Here's how it works in a very general way. The tool and the sacrificial metal are attached to the UNPLUGGED battery charger (Important! tool = negative, sacrificial metal = positive) and placed in a tub of water that has an electrolyte (washing soda) added. When the charger is plugged in and turned on, the electric current flows between the tool and the sacrificial metal and a lot of cool scientific stuff happens! Basically, some rust on the tool is physically blasted off by the bubbles of gas coming off the surface and the rest of the rust on the tool is converted back into another form of iron. While this is happening, the sacrificial metal is, well, sacrificed in a slow and painful (okay, not really...) way as it somehow erodes into the water. Also at the same time, oxygen and hydrogen bubbles are, well, bubbling up.

Now you know why I don't teach science! If you are interested in the exact science of it all there are a ton of sites on this that explain it much better than I do - just google "electrolysis rust removal" and start reading. But seriously, whether you understand it or not, it still works!

On a more pragmatic note, here are some things to keep in mind:

1. Keep an eye on the ammeter - not enough current and the process will take forever - too much current (red zone on meter) and you might fry something.

To increase current either add more washing soda or move the tool and metal closer together (Unplug First!)

To decrease current either add more water or move the tool and metal farther apart (Unplug First!)

2. If the bubbles slow down, but the tool is still rusty, take it out (Unplug First!), wipe it off, and restart.

3. The process is "line of sight", which means you will either have to be patient and rotate things around, or be impatient (like me) and get creative...

4. If the water turns green and foamy, RUN! Just kidding, it's normal.

5. When you take the tool out it will start to rust again. Fast. No really, FAST! Be ready to dry and oil/wax it.

To help deal with my impatience I created a "CAT Scan" rig that placed the tool inside a tunnel of the sacrificial metal.

Here's the carrier board that holds the tool parts. It has holes drilled into it to allow zip ties to be used to secure the parts (you do not want them coming into direct contact with the other metal). These holes also allow the current to get to the bottom of the parts.

Now the carrier board and attached parts is placed into The Fully Adjustable Tunnel of Rusty Doom!TM The vertical "tail" on the tunnel allows the battery charger jaws to be clear of the water (so as not to participate in the sacrifice below the surface).

Each part is wired up to a short jumper bar which will be connected to the battery charger (again, out of the water).

And here is a shot of the rig up and running on the back deck.

A last couple of before and after shots.

Monday, October 13, 2008

Oxford Frame for Robin

Last week while my class of 7th graders was in the school library, one of the library chairs broke. All by itself - "I swear!"

Later, I spotted the chair pitched in the dumpster behind the loading dock. As if it wasn't enough that the chair was a middle school casualty, now the wood it was made of was going to be wasted. Finding this unacceptable I did what any good scrounge/woodworker would do - I climbed into the dumpster after school and shoved the carcass into the back of my truck.

Here's what was left of the chair when it arrived at the shop:

Now Robin, our school librarian, is amazing. She is always doing great things for our kids and school, so I wanted to use this salvaged wood to make some kind of thank you gift for her.

I took the chair apart to see exactly what I had to work with.

After picking two pieces with interesting grain, I cut of the ends to remove the dowels left over from the original joints.

I had been thinking about making some kind of box, but at this point I changed plans. The long, relatively slender pieces just didn't lend themselves to the kind of box I had in mind, so I decide to make a picture frame instead. I sketched up a rough plan for what I call an Oxford frame. I have no idea where I came up with that name, or why it is (maybe) called that.

Next I resawed the two pieces into four, and ganged them together for thicknessing with a scub (just for the few odd high spots) followed by a fore plane with a cambered iron and then a jack with an uncambered iron. (One of the screw hole cross-sections seen in the second picture is still visible on the back of the finished frame - a neat clue to the salvaged nature of this wood.)

After deciding which faces would show, I used a square, a marking gauge, and a marking knife to lay out the half-lap joints. I used a chisel, held by the blade (sort of an icepick grip) to cut vee shaped grooves for the saw to follow. The outside of each groove is the vertical knife cut, while the inside (waste) is the angled cut from the chisel. This really helps me make clean, square crosscuts by hand.

After that, it was just a matter of cross cutting (done with a LN dovetail saw filed for ripping...hey, it works!) and then using a mallet and chisel to pop out the waste, followed by paring it clean. I haven't gotten around to making a bench hook yet, so I am always just using two dogs to cut against. It has been working so well that I may never get around to making that hook.

A quick test fit, then it is off to the stopped rabbets for the glass, mat, picture and backer.

On the shorter pieces, rails in this case, the half-laps are cut in the back the same as the rabbets. This gave me enough room to drop a router plane into the gap created by the lap and then it was easy enough to plane the rabbet using the fence on the plane and lowering the blade after each pass.

On the stiles however, the laps are in the face so this technique wouldn't work. There may well be a way to cut stopped rabbets with a router plane, but I couldn't figure it out. So I reverted to the craftmanship of risk and did it with a chisel freehand. So much easier! Next time I am leaving the 71 on the shelf and just doing it with the chisel and marking gauge.

About this time I needed a break, and Teague came to my rescue!

Here's what the bench looked like at the end of the day. Times like this I am always glad I made the bench as big as I did.

A quick coat of Tried and True and it's done! I hope Robin enjoys it - and I'll try to keep my 7th graders away from it!

Sunday, October 5, 2008