Sunday, May 16, 2010

Sharpening sticks - an alternative to stones for razor edges

A recent email ad from Amazon about sharpening gear jogged my memory about documenting my own sharpening systems.

I have a number of sharpening systems I use, and use them based on what I'm sharpening, and how much shaping of the edge is required.
The systems I use for aggressive removal of material from the edge, centre around the typical stones used in most workshops and homes. A friend from wayback taught me to use babyoil on the standard carborundum stones favoured by butchers and handymen. The lighter oil carried away the metal flakes, and did not clog up the stone as it dried. I have a few "inherited" stones which are sticky and almost tar-ry in feeling with old oil soaked into them.
I also have some water stones such as this, which I use from time to time. My first water stones were actual carborundum stones, but instead of using oil on them, I used water as the lubricant. I eventually purchased a few proper water stones, but only use them occasionally.

I also have some diamond plates. I don't like calling them stones since they resemble plastic backed plates of metal, with the diamond material bonded to the metal. I occasionally use them for aggressive removal of metal, but find they can be too aggressive, and leave deep scratches. Admittedly the plates I have aren't as good as the ones in the link above, but they look similar. I think mine were some cheap chinese knockoffs, so the "fine" is more of a "medium", etc. They have their use, but I don't use them for honing an edge.

I used to be heavily involved in model rocketry, and would still be if it weren't for the firebans in this area. One of the tricks I learnt in model rocketry was the concept of mounting disposal scalpel blades into permanent holders, and then resharpening them as required. I cannot recall the webpage which introduced this concept, but from memory it was one of the HO scale sites.
The sharpening method the site used was perfect for such small blades, and I used it every since for all size blades.
The main premise of the system presumes the blade shape is already correct, and all that is required is to refine the cutting edge whilst preserving the angles. A selection of "wet and dry" carborundum paper is obtained in a number of grits - I used 400, 600, 800, 1000, and 1200.
I obtained some timber of size 35x12 (1 1/2" x 1/2") DAR (Dressed All Round) and cut it into lengths of about 350mm (14"). I cut strips from the wet and dry paper, and glued them to the wood strips using rubber cement. The photo below shows a number of these sticks with the size written on them with a permanent marker, and a 3/8" hole drilled through the top for hanging.

The other side of the stick has another size glued and labeled to it... except the stick on the right. An observant reader will notice 2 sticks with 400, and  1200 grit paper attached. Part of this was due to the even number of sides, and the odd number of papers (including the RHS one), but the main reason for the duplication is the heavy work 400 grit gets early in edge refinement, and the regular use 1200 gets for touchups. These two grit sizes get more work than the intermediate sizes, so they are duplicated. I still use the intermediate sizes, so will not give them up.

The right hand stick has a strip of leather glued to it (again with rubber cement). The leather was cut from a discarded belt, and has then had rouge rubbed into it. The rouge was standard cheap Tripoli, nothing fancy. The leather strip becomes a strop to polish away any fine scratches in the sharpened edge, and to remove any burrs or "wires" I recharge the Tripoli every now and then, but the amount is uses is almost negligible.

So how is this system used?...  The tool to be sharpened will need to have it's edge geometry already formed by some other means. I use stones if minor rework is required, if major rework, then it's power tools to the rescue (grinder)
Once the edge geometry is correct, and all deep scratches are removed by use of a stone (or extra fine diamond plate), I will use the 400 grit stick to start sharpening the edge. I usually choose to hold the stick stationary, and move the tool, but sometimes it's easier to move the stick over an edge.

As the appearance of the edge improves, I will switch the sticks to the next grit up, working from 400, through 600, then 800, and to 1000, and then 1200 grit. By the time I've gotten to 1200 grit, the edge is not changing in shape, but merely becoming smoother, and almost "frosted" in appearance.

The photo above shows a cheap garage sale knife on the 1200 grit stick. Lubricants can be used with these sticks since the paper is designed to withstand moisture, and the rubber cement was chosen for the same reason. Eventually the sticks may warp, but since I dry them after use if I wet them, I've never observed any significant warping - these sticks were made over 10 years ago. The only lubricant I've used on these sticks is water.

The photo below shows the mirror finish on the edge of a knife after using the leather strop.

The above knife was one I found laying on the road when walking to the train station several years ago. The tip had been broken away, and the edge bellied out in that area. (I suspect it had been used to twist something open, and the tip broken off as a result.) I reshaped the point using a grinder, and put a tanto style chisel point on the blade. After some work on the stones, the point, and edge of the blade had a useful blade geometry, and fairly pleasing lines. After using the sharpening sticks on it, the cutting edge (with it's mirror finish) extends from point to ricasso in a width of around 2mm (~1/16") As a knife, it's a rough cheapie which suffered a hard life, but now resides in my workshop as a general utility knife and can cut most things I point it at.

I keep mentioning blade and edge geometry. I've got a couple of books I've read which discuss how to sharpen tools, knives, etc. Both books shown below have their strengths and flavour.

The Razor Edge Book of Sharpening by John Juranitch
This book is good at explaining what to do, how to sharpen common tools, and has some good pictures covering methods, and testing an edge. John is quite vocal about how simple sharpening should be, and illustrates the gaining, and protection of edge geometry well.

The Complete Guide to Sharpening by Leonard Lee
Leonard Lee is a name most woodworkers know from the company "Lee Valley Tools". This book covers the finer detail left out of the preceding book (John Juranitch), and discusses some metallurgy, and the effects of edge geometry on certain tasks, and the effects it has on finish, effort etc. The other main appeal of this book is the demonstration of sharpening methods for common, and some "not so common" tools.

To some up, John's book is good for homeowners looking for some skills in sharpening, Leonard's book is for workshop folks looking to understand and maximise the ability of their tools. I cannot recommend one book over the other, and instead took advantage of the bundling deals amazon seems to run when buying both books together.

Everyday First-Aid kit - gloves and portability

Personal protection during emergency response is the first priority of all responders. After all, it's no good responding to an incident, and becoming a casualty as a result.
Training, exercises, shared experiences all help prepare a person for protecting themselves... and there are also procedures to help (S.O.Ps cover things such as equipment, PPE, and biological protection)

I've attended a few incidents where my first responsibilities have been more of a firstaid/ medical response, as opposed to rescue, or fire. All of these incidents have been motor vehicle accidents (MVA), and the ambulance service has not arrived prior to fire and rescue personelle. The first MVA I worked at, I forgot to wear nitrile gloves under my leather gloves due to the tunnel vision of responding. The discussion with leadership afterwords brought the training home hard. Since then I've prepared some disposable gloves and store them in my helmet for protection.
I purchased some strong disposable gloves (shown in photo below) and sorted the gloves out into pairs.

I then rolled (from the fingers to the wrist) the gloves to exclude as much air as possible, and placed the rolls in some ziplock bags. The photo below shows two pairs of gloves, in the bag - one pair on the left, the other on the right.

The gloves do settle down over time, and the bags never seem to seal 100% against air, but dust, sweat and water don't seem to get in the bag,  so that's what's important.

I got to thinking about those incidents, and came to the conclusion that I would be wise to make up a small firstaid kit. The professionals I work with use the large "Thomas packs", but for my duties and daily roles, this would represent overkill, and would be beyond my current experience and training. My criteria for the kit would be:

1 - small enough to sit on the front seat of my car, and not be in the way of passengers, or work activities.

2 - able to be placed either on my shoulder, or around my waist , thereby keeping my hands free for scaling stairs, ladders, or other paths to an injured person.

3 - contain the essentials to maintain life for the time needed for a fully equipped ambulance to arrive (estimated at 20 mins - worst case)

The intention was to be able to provide resuscitation, observations, and rudimentary bleeding control for a casualty until the ambulance arrives, or until I expect to "run out of steam".. and based on my previous experience, I'd been totally worn out after 20 mins of providing full CPR.

I purchased a "bum bag" off one of the airsoft sellers on Ebay (Note to US readers... "Fanny pack" isn't the term in Oz.. means something totally different here). I wasn't too worried about colours, but went with the typical OD green so dirt stains wouldn't be as noticable. This particular bag had a strap which could be moved from a waist strap, to a shoulder strap, which added appeal for what I was trying to accomplish.

I added a "hard shell" security case I bought from another seller, and filled it with bagged gloves (3 packs, each containing 2 or 3 pairs of gloves). The security case simply clipped on to the strap/belt.
Since the photos were taken, I've added a smaller "pouch" on the side of the bag between the bag and the glove case. This pouch holds a pair of 7" shears for cutting clothing, etc.

The bag as purchased from the airsoft guy has a number of pockets (one on the front, plus one on each end, and the main big section in the middle). I basically put a resuscitation mask, and my observations notebook (with a pencil) in the front pocket (as shown below).

Some standard bandages (not a huge selection, I'll prioritise their use on assessment of the scene), and a selection of bandaids were placed in the middle pouch with a mylar sheet (Space blanket)

A number of safety pins were pinned on the straps dotted around the bag, and some pens were clipped in convenient locations (The aforementioned pencil is my backup).

The downloadable pupil chart mentioned in the previous post has been laminated, and a copy is taped inside the obs notebook, and a strip version is loose in the front pocket.
There's still some room inside the kit, but I won't fill those spots until I have some more experience, or insight on suitable items.

Most of the time I carry my torch, and a Leatherman with me. Between those, and this kit, I'd like to think I'm more able to help others than I was previously.

I've used the Leatherman a few times at incidents and been very impressed with how well it's worked. I ended up procuring a second Leatherman after the loss of my first, and deliberately choose the Charge model for the hook blade, and the intent of using it to cut seatbelts.

I'll do up another post someday about Leathermans (and other multitools), but simply put...

I've owned several pocketknives over the years, some I've sorely missed, others I'd rather forget. I've yet to use a Leatherman I didn't trust, but certain models seem to suit my needs better than others. My previous favorite was the heavy Core model, and upon it's loss, it was replaced with the Charge ALX. I've tested the Charge TTi, Wave,Surge, Fuse, and SuperTool300. They all have their features and purpose, and none has failed to impress me. I've also evaluated a few other multitools for use... I won't mention names, but one particular unit was so bad to hold and use, I couldn't even give it away at the end. My current everyday Leatherman is the Charge ALX, carried in the old nylon pouch from the Core on my belt beside the Fenix LD2 torch. I have a backup Charge TTi in my turnout gear, with a LD20 torch.

Bladesmithing is one of my interests, and once I get the forge finished (yes another project to document) I'll get more into the forging of blades (instead of my previous "stock removal" projects), but I'll still carry the Leatherman.

Tuesday, May 11, 2010

ERT/ EMS/ EMT torch and pupil gauge

I use the Fenix LD2 as my current "every day" torch - it's no longer available and has been replaced with the better LD20 (click here for the amazon listing). The torch has multiple power levels, and can be switched between them quite easily (some via the push button at the rear, others through turning the bezel)
The main appeals of the LD2 series is that the battery life is great compared to the brightness, and the torch is nearly indestructible.(These comments are compared to the 4 other LED, and 3 bulb torches I used in the hunt to find a torch which fulfilled my needs at work) The battery life (in the lower power modes) is amazing, the only problem I've found is stopping other people from "borrowing" it.

I was trying to find a torch for my first-aid kit, and was looking hard at this type of torch. (image taken from a medical supply mob in UK) to clip on my kit, but most I could find contained sealed battery setups, and would be treated as disposable. Not an issue, but in my case the torch might only be needed a few times and the last thing I need is to find the heat has deteriorated the battery.

The main difference between the torch I carry everyday (in lowest power mode), and the medical torch is the pupil gauge printed on the side.
So my solution (for now) is to make up a pupil chart, and have it sitting in my observations notebook, and a strip copy laminated and carried in the pack.
Googling for a printable pupil chart was interesting... millions of  hits, but the only one I found I could download was a PDF Neurological diagnosis flowchart. To make the chart more useable to my needs, I captured the chart from the PDF, and then pasted it into a BMP (Bitmap). Then it was a simple case of copying parts of the image and pasting the pieces in the arrangement that suits my needs.

The BMP file is shown above, and you can download the bitmap chart here

I copied the BMP into a word document so I could print it out at 100%. Download the printable chart here as a word document, should anyone else need this file for similar purposes.

I'll be posting some details on my first aid kit soon, I've built the kit to reflect the incidents I've attended, and what I think I need for responding when I arrive at those incidents. The kit is built from parts purchased on Ebay, and taken from my supplies of kits at home.

Saturday, May 8, 2010

Customised Meter Case - & musings

Before I get into this little project, I just want to say how happy I am Daria is finally coming out on DVD. I've bough the various box sets issued over the years by various companies, but all of them were simply DVDs cut from the "Sarcast-a-thon" showing, complete with the original music, and various station markers, and glitches.. but still Waaayyy better than nothing. But come 11th of May 2010, MTV is releasing the Daria DVD box set - still no news on the music, but again - better than nothing. I'll be buying my copy from Amazon due to the price - Here

The other musing was trying to pick a suitable photo for my profile. There was no way on earth I was going to put a photo of myself up there (It's offend the internet spirits for sure) so I was thinking about suitable "archetypes" I could use... some of the candidates included "Q" (Desmond Llewellyn) - from the James Bond franchise, "Tobermory" from the Wombles, Macgyver, Eeyore, and Alastair Cookie, and I even considered Erik (the Phantom of the Opera), but then I kept coming back to this one choice.... This man displays all the qualities and attributes I'd associate with - quick witted, intelligent, inventive, and a great many other characteristics I wouldn't dare include on a resume such as devious, megalomaniacal, and unassuming dress sense. He's Graeme Garden from the Goodies - if you missed out growing up with the Goodies in your life, take the time to get some episodes and see what the fuss was about. If you know the Goodies, you'll know and love "Graybags", even if you associate more with Bill or Tim.

On to the project...

I use a Fluke 179 DMM (Digital Multi Meter) as part of my work, and carry a number of leads, clips, and spares for the meter. One of my co-workers had a case which had the meter on one side, and the spare leads on the other, but I could not find anyone offering the case, and he'd had it for years. I got sick of carrying two cases to jobs, and so decided to make my own case.

I started with a CD wallet for the local Kmart store (big variety chain store - viz Target, or WalMart). The wallet had a zipper around three sides, and a "clam shell" design based around a firm material covered rubber. All up the case was about 50mm (2") thick when stuffed with cardboard.
The CD wallet is shown below...

I removed the CD sleeves, and salvaged the velcro strips used to hold the sleeves in place. I purchased two "cheap and nasty" pencil cases ($1 each) just to get cheap zips, and purchased a cheap roll-up cutting board for the plastic ($3 for 4 boards). The fabric is from some old work shirts that had become too ratty to wear in the shed.
I sewed up a "pouch" to sit above the meter which holds the spares for the meter (fuses, battery, holding clip)

The divider which holds the meter to the LHS (Left Hand Side) of the case is a piece of the roll-up cutting board sewn into a sleeve of cotton fabric. The salvaged velcro is used to secure the meter into the case. The spare space on the RHS of the meter is used to roll the connected leads in for easy use.

The contents of the top pouch are shown below... the brown wire is the K thermocouple used by the Fluke meters for measuring temperature.

The RHS of the CD wallet was separated from the meter section by a panel made from more cutting board plastic encased in another cotton sleeve. The panel is retained by a fabric hinge stitched in the middle of the wallet (White lines of stitching in photo above), and held in place with a velcro closure on the RHS edge. With the velcro closure opened, the panel can swing over the meter to reveal...

The spare leads are vecro'd in pairs to the top section of the panel. The thin black velcro was the last of the velcro salvaged from the original CD wallet.
The pouch sewn into the lower half of the RHS shell contains the spare tips, and probes. The pouch is a simple sewn pouch with another "pencil case" zipper for a closure.

The entire meter case took about 2-3 hours to make including the cutting, sewing, and hand stitching the pouches in place. I've now been using the case in the field for about 6 months and had no complaints about how well it's met my expectations.

A few sewing notes...
threads were typical 100% polyester threads used for normal sewing.
Sewing needle was a normal Smetz universal needle (#15 from memory) and it handled the three layers of cotton, plus the 1mm of cutting board plastic fine.
I used my Toyota sewing machine for this job since it is my current "work horse" machine. I have an old Elna "Air electric", and a Husky 4 thread overlocker, but those only get used when needed.. the Toyota is my "day to day" machine.

I'll post a review on Daria once I have it my hands!!! - Come on Amazon...

Sunday, May 2, 2010

"free" pegboard - shed tip #1, and magnets

A useful shed tip which saved me some money when I first set up my shed here. I know many people who adore the look of pegboards, with all their tools neatly silhouetted on the board, easy to see what you have, and if anything is missing.
Personally I'm not too fussed on having my tools on display (seems hypocritical after posting about tooling - bear with me), but I do like having commonly used tools in a location that is easy to get to quickly.
When I set up my shed, I considered pegboard, but it's not cheap. I then came across the idea of using an old hollow core door.
These doors get tossed out all the time around here as homes are refurbished. I grabbed some for use as trestle tops, and I took one of these and screwed it to the shed wall, effectively cladding that section of the wall with the door. The door is screwed on horizontally, and flush with the wall top.

Peg board works by having a 6mm (1/4") masonite board, pre-drilled with holes, mounted with a 1" (25mm) gap behind it for hooks to pass through.
A hollow core door is a sheet of 5-6mm masonite, with a 1" gap filled with a light honeycomb of cardboard, and then finished with another 5-6mm sheet of masonite. The whole assembly is edged with a solid wood frame which is around 35-50 (1 1/2 - 2") wide... other than the pre-drilled holes, the hollowcore door would pass for pegboard on a frame.

The photo above shows the door, with holes drilled anywhere I want them, things screwed to the door, things hanging off it... lots of options.
Once the door is mounted on the wall, I simply started screwing things to it, corner brackets for heavy duty hooks, blocks of wood for holding squares or saws. I can drill holes where ever I want for hooks, the tail of the hook simply crushes the internal cardboard if it's in the way.

Another thing which is good about the doors is that I could screw hard drive magnets to it where ever I want. I dismantled a number of harddrives over the years - mostly for collecting material for the furnace, but I also salvage useful components such as platters, magnets, and bearings.

The magnets get used for all sorts of things, but one common use is for holding things up. The photo below shows magnets screwed to the door and labelled for the hammers they hold.

I've yet to find a hook I'd trust for holding up my sledge hammers, but is easy to remove, or replace the hammers on. The photo below shows my club hammer attached to the wall via the magnet.

I'd show a better picture of some of the other things hanging on the wall, but it's hard to get a decent photograph through all the mess in the shed.

The magnets also get used for holding charts to the roof of the shed. I ran out of wall space in my shed pretty quick. Between shelving, door, tool storage, and a bench, the walls seemed to disappear pretty quick, so I stored my thread/ drilling charts on the roof. I simply covered the charts in contact, and then used some magnets to attach the corners to the roof.

So shed tip #1 - free pegboard by using hollowcore doors, and drilling your own holes where you want them, (as you need them, etc)

Bonus tip - save hard drive magnets for use for holding tools to walls, etc. I use one magnet for a 35lb sledge hammer - they are dynamite for holding, clamping, etc - and free for minimal labour.

Saturday, May 1, 2010

Indicator stand - magnetic - disassembly

I obtained a very damaged indicator stand (magnetic) which was to be thrown out. The damage includes the lack of the main post, all clamps, and the magnetic base is damaged by the loss of the front plate, switch lever, and some dings.
Below is a picture of what a complete stand should look like, with an indicator on it (picture taken from the Amazon listing for the Grizzly indicator/ stand set). I will rebuild the damaged one back to this level of usefulness, and use it with my existing indicator.

Before I can repair the damaged unit, I need to disassemble it, determine what needs fixing/repair, and then proceed from there. This page will cover the disassembly, another page will be written up to cover the rebuild once I've done it.

Since the front panel was already missing, I simply removed a brass lock screw from the side, and tried to remove the magnetic core from the internals of the base. I found the only way to achieve this was to tap the corner of the base on a block of wood, with the open end downwards, and use momentum of the core to pull it out (similar to a kinetic puller if you're into reloading) Once out, the pieces were laid out as shown below...

The pieces are: (from left to right) remains of actuating lever, magnetic core, spacer ring, base.

The base is a metal component, a singled piece, but it's made of four sections. All of these sections are visible in the photo below. The two sides (bulk of the base) are made of a cast iron, separated by a brass section about 5mm (3/16") thick. The final section is a zinc/epoxy shield which covers the hole at the back.

The brass separates the two iron halves, and effectively "breaks" the magnetic circuit between the two halves.

The magnetic core resides in the hole in the middle. The core comprises a strong magnet, with some pole pieces to direct the magnetic flux across the axis of the core. Some bonded plastic flanges are located at each end, and these plastic end pieces have a square hole molded in for turning the core.

The above photo shows the core with it's endpieces (the one on the right has a spacer ring fitted), whereas the photo below shows the square hole in the end for turning the core...

The spacer ring is to prevent the magnetic core actually contacting the interior of the base during normal operation. The diameter of the core is measured at 0.8mm less than the diameter of the hole it rotates in. The spacer ring is measured to centre the core in this hole, and this gives a rotating clearance of less than 0.5mm between the magnetic pole pieces, and the base.
The small gap is designed to offer minimal attenuation to the magnetic flux, but still permit rotation of the core. The base is designed (with the brass strip) to offer two flux paths from one side of the core to the other...
One path is through the iron side, through the magnetic material contacting the base, and then back through the other half - this path is the path which "grabs" whatever the base is sitting on.

The other path is where the flux flows within the same iron half - the flux path is vertical, and splits, with half of the flux circulating in the left hand iron side, the remaining flux in the right hand side.

That pretty much covers the internals of a magnetic base, and roughly how it works.
To repair this stand I'll be doing the following:

a - Machine a front spacer ring
b - Build a new actuating lever
c - Build a face plate to hold the lever
d - Build a post including mounting threads, washer, locknut, etc
e - Build the clamps, bars, etc to connect the indicator to the post.
f - Paint/ finish the components

As always I'll photograph as I go, and document after it's done with comments and findings.