building a folder

Sorry to hear about Gene, I think this has happened to him before, there are some REAL ARSEHOLES about.

OK gents here's the next installment, plenty of pictures so I hope that you all can follow me. First let me say that this is the way I fit the bar because it works for me, some guys fit the bar from the front, (I've done that too) but I find this easier.
Cut out, from your photocopies, a bar and a spacer and glue them to the appropriate pieces of 416 (spacer .1235" and bar .1215"). Figure 9 shows this and notice that I've left plenty of meat around the drawing.


Figure 9

Clamp the spacer to the template and use it to drill the 2 holes, remove and cut the spring slot on the bandsaw. Put this aside for now.

Place the the bar in the filing blocks and file and polish to 1200 grit, the front of the bar. Remove and reposition the bar so as to file and polish the bottom of the lock-bar tab. Figure 10 shows how I position the bar in the blocks.


Figure 10

Remove the bar from the blocks and radius, with wet and dry, the corner of the bar at the front and bottom. Scrape the drawing from the front 3/4" of the bar, clean with wet & dry and paint with marking fluid. When dry put the front of the bar against the front of the lock notch, twist the bar 90 degrees and using the rear of the notch scribe a line across the bar. Then with a steel scribe mark a line a couple of degrees from the bottom to the top. Figure 11 explains this a little better, you should be able to see the 2 lines that meet at the bottom of the bar.


Figure 11

Put the bar front first into the filing blocks and line up on the tapered line (ie the line that was scribed on after marking with the rear of the notch). Using the edge of a file cut the back of the tab to about .100". What I am doing is filing a taper at the back and once we get the bottom corner of the back of the bar almost in I will straight the bar up until the bar wedges in. Figure 12 shows the bar in the filing blocks.


Figure12

At this early stage I don't polish the back of the tab, I finish with a worn mill file. Remove from the blocks and radius the bottom rear corner. Place the front of the bar against the front of the notch and hold up to the light, this will give you an indication of the amount of metel that still has to be removed. I now lightly rub some of the blue marking fluid off, just enough so I can still see my scribed lines. After you have used your filing blocks for some time they become highly polished (almost like a mirror) so when you repeat this process you'll find that you can actually see .001". Repeat this process taking off very small amounts, and slightly straighten the bar in the blocks. When I get close where the bar is starting to go in I polish the back with 600 grit.
This is the most crical stage so don't be in a rush, because if you take too much off you can't put it back. Normally it takes me about an hour to fit the bar and when I'm finished, the bar and the blade are one unit, I can hold the assembly by the rear of the bar and not see any light around the tab and the notch.
Figure 13 shows the bar fitted to the blade.


Figure 13

Next step is to drill the bar pivot pin hole. On the template insert the blade pivot pin, bearing, blade and bar (as a unit), and rotate the bar/blade until the top and bottom profiles look OK (the top line on your drawing will give you a starting point). At this stage it should be obvious why I leave plenty of metal around the drawing, any small angular deviation from the linr of the front of the bar will raise or lower the rear of the bar. Once you are happy with the profiles clamp the blade/bar unit to the template across the notch (Figures 14 and 15 show this). I use a piece of pigskin to protect the blade/bar unit, then drill the bar pivot hole and drop in a try pin. Unclamp and raise the bar out of the blade. With your finger acting as a spring lock the bar to the blade, there should be no movement between the 2 pivot pins and the lock.


Figure 14


Figure 15

Notice on figure 14 that the top of the bar is below the line of the drawing, so I now grind down to this line (it still leaves me metal to remove) and I also grind the bottom of the bar to a line from the top of the rear of the tab toa pint about 1/16" below the bottom of the drawing. Figure 16 explains this better. Rotate the blade into the closed position, if you havent ground enough off the bottom of the bar the blade will hit the bar. With the blade in the closed position the top of the bar should be below the position it was when in the open position. If not you will have to make a new blade and bar. Remember when I profiled the blade I left extra meat at the bottom of the tang, well this is the spot that determines where the bar is in the closed position.
Figure 16 shows the tip of the blade well below the bottom of the handle yet the top of the bar is well below the position it was in the open position. By removing metal at point 1 it raises the tip of the blade, removing metal at point 2 drops it in. In this case I've got plenty to play with.


Figure 16

In the next installment I will fit the spacer, spring and hopefully the blade to it's almost finished position. Don't forget, If you have any questions don't hesitate to ask.
Man this is tiring work, I have to plan my approach very carefully.

Regards from Australia

Neil,
This is by far the best tutorial I have ever seen! It is exactly like being in your shop. I can't wait to see how it turns out and then go out and make my own.

I'm glad to hear that you'll be quitting smoking. My entire family and all of my friends smoke and I'll tell you that I've really come to admire people who are able to quit. It's one of the most socially acceptable addictions I know of. Hope you feel better.

Reuben

Neil and men ...

These are looking like CKD "hall of fame" posts here. What do you think?

With your permission, I would like to setup the actual technical posts by Neil in their own read-only thread and we can open a discussion thread below them, so we can have them organized for future reference.



:
Alex

No problem Alex, makes sense to have them all together. Reuben, you wouldn't like to be in my shop mate, there's that much junk and @#%$ in there my wife is absolutely amazed that I can actually produce knives in there.

Regards from Australia

Neil,

I guess I should quit using the little smoking man icon on your forum. :

I'm sure it doesn't help you forget any quicker!

Sorry man!

Alex

Alex,

Until you mentioned it I never even noticed.

Neil,
I actually keep my shop in complete and utter dissaray but I recently found a friend who is semi interested in knife making. Now that I have him in my shop doing work on his knives I find that it's neccesary to clean things up. It's hard to yell at him for not leaving something where I can find it because in reality everything is just sitting around in a big pile near my work benches. Once something has a place I can complain that he didn't put it back there. If I ever go to Australia I will be sure to look you up.
For someone such as myself who doesn't own a surface grinder would you say it is safe to simply belt sand my blade and parts until things seem parallel and are the correct width or are the fractions of an inch the difference between a knife that moves with the correct amount of friction and a knife which is either too slopy or too rough in its action? Would you recomend looking for a local machine shop that would be willing to do some grinding for me?


Reuben

Reuben,

Trying to "surface grind" using a belt grinder ain't easy, I have used a disc, it used to take me all day to get the stuff parallel. You need to be accurate to within .0005" otherwise you run the risk of things going wrong and you'll only find out at the end. If you have access via a machine shop, for a reasonable price, you're better off going down that track. In fact this is what I used to do before I bought my machine, I had a mate who worked in a machine shop as a tool-maker.
I would shop around and see if you can pick up a cheap second hand machine. I don't only use my machine for folders, I use it to make jigs and tools and also I surface grind my steel for fixed blades.

OK, here's the next installment where I fit the spacer and spring and fit the internals up almost to finish stage.

Figure 17 shows the spacer drawing glued to the 416 (I did this earlier remember), I now cut it almost to the line on the drawing, remove the drawing and lightly countersink the holes and I also remove the drawing from the bar and lightly countersink the bar pivot hole.


Figure 17

I now put the spacer and blade between the 2 sides of the folder and grind the spacer flush (I put the blade in to keep the sides parallel), remove the spacer and de-burr. I had cut the spring slot on my bandsaw previously however my spring material (which I buy from Texas Knifemakers) is 1/8" wide and 1/16" thick so I need to open up the cut. I do this using a 1.5mm "gaping file", which is a file with teeth only along the edge (see picture). 1.5mm is only .004" thinner than 1/16" so I can remove the excess on my belt grinder satisfactorily and I also redus\ce the width to less than .1235". The following is a not very good picture of my file.


Gaping File

I then place the spacer on one of the folder sides, put the blade in and rotate it to the closed position and mark the bottom of the spacer with the shape of the cutting edge.
With a pair of dividers I measure, from the drawing, the distance from the bar pivot to the front of the spacer and using that distance I put one leg of the dividers in the bar pivot hole in the folder frame and scribe a line on the spacer (after marking it with fluid), I do the same with the bar. I then grind to the line (Figure 18 shows all my marks)


Figure 18

Before I go any further I want to stress that all of the curves are set up to suit my machines. The distance from the bar pivot hole to the front of the spacer is approx. 1 3/4" as I have a 3.5" contact wheel and the curve from the bottom of the tang to the kick is ground on my 1.5" contact wheel. Figure 19 shows the spacer and bar ground to fit and the bottom of the spacer ground to accomodate the blade in the closed position. The red mark you can see is where the spring comes to and I now cut the spring and fit it in the spacer. To keep the spring out of the way of the blade (in the closed position) I grind a step in the bottom of the bar. I also bend the spring to increase the tension.
Figure 20 shows the spacer, spring and bar all fitted together.


Figure 19


Figure 20

Notice the mark that I have numbered "3", with the blade in this is the position of the bar in the open position, depress the bar and swing the blade to the closed position. If there is enough tension on the spring the blade should spring closed, if not just bend the spring some more. With the blade in the closed position "3" should be below the top of the spacer. With this particular piece I've left enough meat at point "1" to ensure this. On my 1.5" contact wheel I CAREFULLY grind some of this metal away which raises the bar in the closed position and also raises the tip of the blade out of the frame (I grind on a 240 grit 3M trisac belt). As the bar starts to raise up to go to a 600 grit belt, which is slower to remove metal. When the bar is close to the mark I stop, at this stage. Figures 21 and 22 show the folder fitted up and functioning properly.


Figure 21


Figure 22

I now assemble the whole knife and in the OPEN position I grind the bar flush with the frame. I dis-assemble, remove the burrs and reassemble and put a single drop of oil in the mechanism. With a brass push rod I depress the lock-bar and close the blade, yes the bar is still below the level of the frame (at the spacer) and has a nice action. Hot dog.
Figures 23 and 24 show the knife finished to this stage. The red line is end of my grind.


Figure 23



I will now grind, polish and heat treat the blade.
Before I heat treat the blade I will relieve the frame (to prevent scratching of the tang). This will be the next installment and as I'm a slow grinder and polisher it will probably take a couple of days, besides it's my Birthday on Sunday the 7th and I'm DEFINITELY not doing any thing that day.

Regards from Australia

I've surprized myself and actually got the next installment done. Grinding the blade and relieving the frame (liners).

I marked out and hollow ground the blade on a 10" wheel, first with a 60 grit belt and then a 240 grit belt, and being impatient I did a trial etch with a cotton tip on the blade to see what it will look like. Doesn't look too bad. Figure 25 shows the result.


Figure 25

Having ground the blade I can now relieve the frame (liners). First off I put the bar on the frame and mark the bottom, then mark where the plunge cuts on my grind come to on the frame and extend this to the line marking the bottom of the frame. I then put the blade pin, bearing and blade on the frame and mark the front of the notch and the circle subscribed by the tang, I then repeat the process for the other frame half. Figure 26 shows my marks.


Figure 26

I relieve the frame halves (liners) on my mill-drill using a 1/8" bottom cutting solid carbide burr running at 2100 rpm on a rotary table on which I've mount a milling plate. The frame rotates around the pivot pin and is a lot easier than manually scraping the frame and the end result is much better. The milling plate is centred over the centre of the rotary table and all I do is drop the frame on, set my downfeed counter to zero and mill off .004". Figure 27 shows the frame set up on the table and it has been milled out.


Figure 27

I repeat the process for the other frame half then go round the milled edges and remove the burrs.

Figures 28 and 29 show the finished result. By putting the 2 halves together you can get a better appreciation of the effect of .004" off each side. This will eliminate the possibility of the tang being marred with ugly scratches in the end result.


Figure 28


Figure 29

Well tomorrow's the 7th and I'm going to have a bludge (that's aussie for doing sweet bugger all).
My next step (after polishing the blade and heat treating it) will be to mill out the frame halves and put in the release notch, so Ill catch you all then.

Regards from Australia.

Neil,
This is some good stuff. I'm glad to see it is for lockbacks too. I don't make liner locks any more, only lockback designs. You explain it very well and the pics are great. Very good job.
We are very priveleged to have you here.
BTW Bob Warner mentioned the knives stolen. Those are the same ones stolen back in July while I was at ABS school. It only happened once. People have been so good to pass the word around. We haven't heard a word about them otherwise.

Wow. Incredible!!! I have read the Clay, Lake and Centofante book, but your tutorial is so much clearer and easier to follow!

This is great stuff Neil. I may never make a folder like this but I'm learning a lot just from looking at your posts.

More than that, I'm always going to appreciate hw much precision work goes into making one of these works of art.

Roger

Thanks gents for the kind comments, this project should be seen as an adjunct to the book "How to make Folding Knives" not as a replacement. I still refer to the book from time to time as a reference.

I wasn't going to do anything today but things got the better of me, so what this is about, for those who are interested, is my milling plate for relieving the frames.

My rotary table has a 6" table with the centre having a #3 morse taper. This plate is made from 3/8" mild steel plate measuring 4" x 6" and a plug that has a 1/4" hole drilled in the centre and has been turned on my lathe to a #3 morse taper. Into the 1/4" hole I've pressed a folder bearing with a 1/8" centre hole. Figure 30 shows the parts of the milling plate and Figure 31 shows the plate on the roary table. The other holes have been drilled and tapped for clamps to hold the folder frames flat.


Figure 30


Figure 31

Regards from Australia.

Happy Birthday, Neil!!