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Bill Harsey
03-25-2011, 06:22
There are times when scissors are the correct tool or even the only tool for a job.
Scissors get dull too and then the correct tool for the job isn't.

I'm thinking about the medics here.
Do your scissors always work like you want?

We can get them sharp again with hand stones and a couple critical steps.

If any interest, will continue.

Constant
03-25-2011, 07:05
We can get them sharp again with hand stones and a couple critical steps.

If any interest, will continue.

Mr. Harsey, please do. Usually I'll just carry three trauma sheers and as one goes dull just toss it. Easy to resupply here in the states but at a FOB I'm not so sure.

Tatonka316
03-25-2011, 08:53
"SEND IT!" Brother Bill! :D

molon labe:lifter

craigepo
03-25-2011, 09:40
I would also like to see something on this, not for medic's shears, but for game/poultry shears. Cutting through pheasants dulls the crap out of those things. I took some fairly high-dollar shears to bass pro shops to get sharpened---I think they did more harm than good.

Bill Harsey
03-25-2011, 14:22
Looks like we have a project. :lifter

Have some deadlines to meet, be back.

Kit Carson
03-25-2011, 21:41
Bill, my wife is a quilter and seamstress and I sharpen her scissors quite often. I'm lazy and just do them on the Burr King..:)

Lets add sharpening loppers, pruning shears, and all those whatever they are called...things you cut limbs off trees..

Team Sergeant
03-25-2011, 22:14
Cool I'd like to know too. And while you're at it how the hell do you sharpen one of these?

CA_TacMedic
03-25-2011, 22:37
I am also interested...no deadline necessary sir, I will be patient. I also carry more than one pair of EMS shears as they go dull pretty quick in addition to the pivot point wearing out and allowing the blades to gap or spread around whatever item is being cut. This typically comes down to a quality issue as there are some poorly manufactured shears on the market.

I also make a lot of tactical gear and cut nylon and webbing regularly and would love to have a sharpening lesson for those. After wasting $$ on cheap ***insert cheap chain store name here** scissors I have recently invested in some quality shears, scissors and thread nippers. Any information that would prolong the use of that investment would be appreciated.

Thanks in advance for your time.

Bill Harsey
03-28-2011, 11:04
Kit,
I have done that too but with the small fine scissors I get better results with fine hand stones. Scissors first but I have sharpened everything you mention. My favorite pruning tool has a pull rope.

Craigepo,
sorry.

Constant,
this thread is for what you guys do.

CA TacMedic,
As you have observed, manufacturing issues. You should be able to break the blades in half before the pivot gives up.
Your fine scissors and thread nippers are in the class of fly tying scissors of which I have about 6 pair.
One of these is a surgical scissors with curved blades and please do not work on those until your confident of the results on your straight bladed scissors.

Team Sergeant,
we will work on that later.

Bill Harsey
03-28-2011, 11:23
Scissors are two blades that pass each other.

Take a careful look at your scissors.

Please observe how flat the inside of each scissor blade is.

This may be a flat surface or slightly "hollow".

No matter what we do, we will not put any bevel on the inside of the scissors blade.

When I say 'inside" I mean the surfaces that touch and by pass each other as the scissors are closed.

First you need to gather some some medium and fine stones,

For the critical step, you are going to need to make or get a leather strop and find a way to load it with fine green (chrome oxide) buffing compound.
Here I just use a strip of 9-10 ounce leather about two inches wide by twenty something inches long but for scissors you could cut those dimensions in half or smaller.
Thinner leather can be glued on a flat board. Leather must by one of the tanned but not oil tanned (soft) types. Hard leather like Oak tanned works best.

To load the green buffing compound I use WD-40 and soak the end of the green buffing stick in it, soak the leather with WD-40 and just rub it in. There is a lot of latitude in this process and is difficult to do wrong. Let dry overnight and it's good to use.

This strop will work on every knife you sharpen and is for both scissors and knives the critical last step to full sharpness.

Reason for the green colored chrome oxide buffing compound is that it's usually a fine abrasive that works well on hard steels.

Bill Harsey
03-28-2011, 12:22
Open and close the scissors as you find them.

If there is any bumping or snagging as the blades pass each other this means you have nicks or burrs on one or both edges.
A burr on one side of scissors dulls a spot on the other.

There are scissors so trashed that hand sharpening is going to be very time consuming and may not be worth it but they are valuable for practice.

Like a knife, look at the scissors edges to see what your starting with. What I look for, using good light, are flat spots or dings on the edge. See what these look like before starting. Repeating myself? yep. read this again. ;)

So if there are nicks on the scissors edges we need to start there first.

I said no bevel on the inside of the edges. That is an exact statement.

That said, we need to carefully and lightly re-flat the inside edge of the scissors to at least straighten out the burrs or nicks. I like to do this before starting any work on the main sharpening bevels.

Open your scissors as far as they will go. Figure out how to grasp them firmly with one hand (and the holding hand can rest on bench/table or knee) DO NOT CLOSE SCISSORS UNTIL LAST STEP OF STROPPING. Please.

To clean up inside burrs place the stone on the back of the blade then rotate it to the edge until contact is just made. This is the only angle for cleanup of inside edges on scissors.
Get a feel for this.
Do not roll the stone off the end of the tip when doing this lapping.
Go slow and careful. Do not over do this, as soon as a good flat is perceived, quit. By flat, I mean hairline width flat along the edge of blades if hollow ground and flat ground blades do not need material removed from surface, only enough stone work to make burrs as flat as the blade...
Hope this makes sense.

*Hand sharpening scissors is a bit tricky in the handling and care needs to be taken as you go to minimize the draw down of the band-aid supply.*

Reason scissors remain open for duration of all sharpening steps is because we do not want any burr at the edges from sharpening process to collide with the burr on the other side and make little flat spots as the edges rub past each other and break off.

I prefer small flat ceramic stones for this work. medium and fine grades are good. If you use diamond it had better be very fine grit.

We have not started sharpening yet, get your strops figured out first if you can.
This is how we remove the sharpening burr and make the scissors full sharp.

Bill Harsey
03-29-2011, 10:39
Sharpening scissors is the same process as sharpening one side of a knife...

...except we have to deal with the other side of the scissors being attached.

Keeping scissors intact actually helps because in the recent past I've taken apart some scissors to try and sharpen holding each half and the first problem encountered is there isn't as much to grasp for control when doing all hand held steps.

Just searched for my favorite ceramic stones by Spyderco, they are listed as "discontinued". Was going to show ya what they look like.

Edited to add: Often a pair of scissors have a different bevel angle on each side. This is part of why I say "look carefully".
In my own shop terms I call this type of scissor "edge and anvil" for how they are set up to cut.
I'm sure there is a proper term somewhere.

CA_TacMedic
03-31-2011, 22:42
I just purchased some scrap leather...it is thinner and I am going to glue it to a 1/2" x 2" board (20" long) and then load it with the rubbing compound (on the rough side) and finish as you stated. I used my google-fu and found a lot of articles on various designs and assembly ideas. I am using a few tips from the various sites. With your permission I can post some of the links to help others out if needed unless you have one that is better suited.

The reason is I want the strop to be done correctly and spent some time searching is I was not completely clear :confused: :confused:on the assembly parts and I wanted to avoid doing any damage to the finishing steps in sharpening.

Dusty
04-01-2011, 02:29
I just purchased some scrap leather...it is thinner and I am going to glue it to a 1/2" x 2" board (20" long) and then load it with the rubbing compound (on the rough side) and finish as you stated. I used my google-fu and found a lot of articles on various designs and assembly ideas. I am using a few tips from the various sites. With your permission I can post some of the links to help others out if needed unless you have one that is better suited.

The reason is I want the strop to be done correctly and spent some time searching is I was not completely clear :confused: :confused:on the assembly parts and I wanted to avoid doing any damage to the finishing steps in sharpening.

Would it be dumb to spend 70 or 80 bucks on an Illinois or similar quality strop?

Bill Harsey
04-01-2011, 04:58
Would it be dumb to spend 70 or 80 bucks on an Illinois or similar quality strop?

No, as long as one can afford it.

I've found it handy to use the strop lying on the edge of the bench for support.
Most of the razor strops are built to be suspended from one end.

A while back I was talking with an old knife making friend, Master Bladesmith Wayne Goddard, and we both agreed that using leather with the green chrome oxide buffing compound rubbed into it is resulting in the sharpest knives either of us has done.

This works the same on scissors.

Next up, actual sharpening.

Bill Harsey
04-01-2011, 05:05
I just purchased some scrap leather...it is thinner and I am going to glue it to a 1/2" x 2" board (20" long) and then load it with the rubbing compound (on the rough side) and finish as you stated. I used my google-fu and found a lot of articles on various designs and assembly ideas. I am using a few tips from the various sites. With your permission I can post some of the links to help others out if needed unless you have one that is better suited.

The reason is I want the strop to be done correctly and spent some time searching is I was not completely clear :confused: :confused:on the assembly parts and I wanted to avoid doing any damage to the finishing steps in sharpening.

Load the compound into the smooth side of the leather.
This is why I use the WD-40, to get the buffing compound to start to work in.
The first moment you start this it will seem like it isn't going to work. Just rub it in then keep going and after the base starts to stick and dries once, then rub more on without any WD-40.

Here the strop is just two pieces of Oak tanned leather glued together for stiffness, smooth sides out.

Bill Harsey
04-01-2011, 17:08
First step, hold scissors with stable grip.
These are fly tying scissors my fishing guide and professional fly tying friend had been using in the boat. His words not mine, "they are trashed".

Bill Harsey
04-01-2011, 17:13
Next step, with flat side of stone is to knock down the burrs on inside of blade flats.
Be very careful to keep stone as flat as possible on each blade.

Bill Harsey
04-01-2011, 17:18
Sharpening the bevels with fine diamond stone.

Bill Harsey
04-01-2011, 17:32
Checking for burr on the backside of blade with fingernail.
If no burr is perceived or felt this means not enough sharpening of the bevel has been done.

Do not change the angle of sharpening, just do some more of it and re-check until fine burr is felt.

What is not shown is visual check of any flat spots out to the point....
and there was so a bit more sharpening of the bevel needed to get done.

Bill Harsey
04-01-2011, 17:40
Before this last step I final sharpened the bevels with the dark colored ceramic stone (after the fine diamond) and then did this which is the stropping of the edges by pulling the bevel backwards over the strop. I use some pressure in this step, note where the line of the scissors can be seen as first placed on the strop.

About 3 to 4 short passes each side are all I did. Then I oiled the blades and carefully closed them for the first time since sharpening began.
I do this slowly in case any burr stops the smooth closing of the scissors.
If this happens, re-strop then try again.
If this doesn't do it go back to gently re-flatting the inside of the blade, re-strop and see how they feel.

I handed the scissors back to the owner and photographer of this sequence, Barrett, to see if they passed inspection. Barret using just the tips cut a single elk hair on the long bias.
The scissors passed inspection.

x SF med
04-02-2011, 12:01
I just purchased some scrap leather...it is thinner and I am going to glue it to a 1/2" x 2" board (20" long) and then load it with the rubbing compound (on the rough side) and finish as you stated. I used my google-fu and found a lot of articles on various designs and assembly ideas. I am using a few tips from the various sites. With your permission I can post some of the links to help others out if needed unless you have one that is better suited.

The reason is I want the strop to be done correctly and spent some time searching is I was not completely clear :confused: :confused:on the assembly parts and I wanted to avoid doing any damage to the finishing steps in sharpening.

Rockler and The Woodworker's store both have very nice pre made bench strops for about $20. The cost is about the same as making one yourself - less if you think about the time involved in making your own. they also have 'small' sleeves of green polishing compound... they'll last a normal guy (Not Bill) at least 3 years. Melting the compound with a lighter works for charging the strop too.

If you get a chance - go to a knife show where Wayne Goddard is giving a sharpening seminar, I try to make at least one a year and learn something new every time. Bill has been an invaluable resource in teaching me how to properly sharpen knives. I knew I was learning when he tested some turning knives I had re-faced/ re-edged/sharpened for my FiL... a smile and "I'll wrap those for you".

Bill Harsey
04-02-2011, 19:27
x SF med,
You do great because you tried and paid attention.
Many don't take the first step which is just trying.

If one just tries we can sort out the details and small problems as ya go.

Bill Harsey
04-04-2011, 12:43
If one has, as previously described, a pair of scissors or EMT type shears that have a loosened pivot and are worthless because of the loose pivot you can try this:

If there is no pivot screw to tighten and it's a machine swaged or press fit pivot one can try re-hammering the pivot pin.
First get some oil in the joint then try a couple taps with a flat hammer and see if it's tighter.
Place the other side of the pivot down on a solid surface preferably a flat chunk of steel then take two taps and then check, repeat and try again until the fit seems right.
Start with very light hammer taps.

It's easy to make the scissors completely not movable too.

If ya do that, the fix goes like this, drill out pivot, take measurement of pivot bore then turn a piece of 303 stainless steel on the lathe with head of correct diameter of head, cut to correct length, place in scissors with pre-greased pivot bore and joint then peen over the head.
A washer under the peened side helps with contact area. Be sure to allow for this in the pivot length.
Or just throw out the scissors.
This is why I say go carefully when hammering.

CA_TacMedic
04-05-2011, 01:00
If there is no pivot screw to tighten and it's a machine swaged or press fit pivot one can try re-hammering the pivot pin.
First get some oil in the joint then try a couple taps with a flat hammer and see if it's tighter.
Place the other side of the pivot down on a solid surface preferably a flat chunk of steel then take two taps and then check, repeat and try again until the fit seems right.
Start with very light hammer taps.

That is how I do most of mine.

As for the sharpening lesson, I just finished my first pair of scissors. Wow, I cannot believe how many burrs were hitting upon closing. I fixed them and sharpened the bevels as in your lesson with ultra fine diamond. Once I could feel a burr I stropped both blades. And checked for burrs...still had a couple, so I re stropped.
I am not sure if I over-sharpened and created too much burring, but I had to strop quite a bit to get the burrs down. After that the scissors are better than new. Cutting at the tips of ^" shears I cut some medium mil-spec webbing without a stumble. Thanks Bill! Worked great. One down and about 20 to go.....20 more opportunities to jack up or learn! I 'll go with learning.:)

Thanks Again.

DDD
12-05-2011, 14:44
I just reread this thread, then immediately modified the method because I don't have access to a strop. Anyway I used the ceramic sticks from a Spyderco Triangle Sharpmaker, they seem sharper to me, but we'll see what the owner has to say...:munchin

Bill Harsey
01-30-2012, 11:06
I just reread this thread, then immediately modified the method because I don't have access to a strop. Anyway I used the ceramic sticks from a Spyderco Triangle Sharpmaker, they seem sharper to me, but we'll see what the owner has to say...:munchin

Removing that final burr from sharpening is critical with scissors because the two edges have to sweep by each other under pressure.

If the edges are slightly ragged or rough on first closing, it flat spots the scissors blades and they are not as sharp as they could be.