run out

[Ray Rogers]

Wow Dennis! You sure know how to raise the bar. After reading your post I think it is easier to understand why so few makers choose to make balisongs. I've never made one, but I'll throw out a few ideas and hope you find something useful.

My primary interest is simply learning how to end up with accurately drilled holes.

Whar are 'accurately drilled' holes? Answer1: holes of the correct size (drill undersized holes and ream to finished size).
Answer2: Holes that are perpendicular to the surface being drilled. My way of accomplishing this is to use my drill press to mill the brass jaws in the drill press vise. After that, anything clamped in the vise is always guaranteed to be perpendicular to the running chuck.
Answer3: The holes are located in the desired position. There are many ways to do this, some highly technical requiring precise measurement and some empirical. The bottom line is you have to know where you want the holes to be and mark that spot. Use a spotting drill to start the hole (this is with the drill press running of course so run out is already taken into account), then switch to the required drill.

It required 4 holes drilled in a diamond pattern

Really? Are you sure? Most balisongs that I've seen only have 3. The tension and positioning for the closed handle is controlled by the tang area of the blade working on a portion of the handle. Aside from that though, what if the closed stop pin were further out, even by an eight of an inch? As long as the handles clamp on it, it should still do it's job. The point I'm trying to make is that the way you define a problem pretty much dictates the solutions for that problem. Rigid definitions require rigid answers. Maybe there really is a reason why these 4 holes have to be perfectly positioned, and then again, maybe there isn't. Perhaps it wouldn't really hurt anything if they were 2 thou or 5 thou out of position (not enough to be easily seen with the naked eye) and then accomodate that by adjusting the mating suface on the handle - much like adjusting the lock work on any other folder.

The stop pins prevent the closed handles from moving side-to-side on the pivots.

Shouldn't there be some washers in there reducing that movement? I know how a balisong is expected to be used but the high dollar ones I have seen have washers.

The slightest deviation in the stop pins will cause the blade to "tilt" too far to one side or another

The diviation in question is a variation from the perpendicular? Refer back to Answer2 above.

and ruining a piece of damascus with improperly drilled holes (one was off by a few thousandths)

Maybe. If it was out of position by a few thou there was possibly somewhere else in the system that could could have been adjusted for that - a little extra meat on the handle or a few more thou on the diameter of the stop pin. If the hole was not perpendicular, it could be plugged and redrilled, redrilled slightly oversized for a larger pin, or a bushing pressed in a drilled to the correct size. Or, a bushing pressed in and drilled slightly off center so that the center of the hole is in the correct position.

lighly spot anneal the tang so that I can knock in the stop pins without splitting the hardened steel

Nothing wrong with that but it's not absolutely necessary. You said 'knock' indicating (to me) hammering. An arbor press could press a hardened pin, oversized by 2 to 4 thou, into that hole without annealing and with little risk to the blade. Even a hardened pin is usually considerably softer than a blade and the harder blade can shear off some of the pin's surface. Just something to consider if you are concerned about heating the blade.

I realize I may not understand all the issues with which you are dealing in making a balisong since I haven't made one. Hopefully, some of the things I said here may help with the actual construction. Most important though, is what I said about how you define a problem. Don't make it more complicated than it has to be........

[Osprey Guy]

Ray-

As always thanks for the quick response.

Thanks for the drilling tips.

My short answer to all of your balisong questions is the same one we gave another fellow not too long ago in reference to liner locks...

"Get a kit!"

With one of Darrel Ralph's Typhoon kits you would understand within seconds why there are two stop pins...and why they must be dead-on accurate.

I don't have time now...I'll try and post a pic or drawing later on to help explain.

Dennis Greenbaum

Yeah Baby!

[Osprey Guy]

Rather than go through the hassle of shooting pics and/or drawing an illustration of a balisong, I thought I would just "borrow" this thread from the Balisong Forum. These pics were just posted and clearly show the diamond pattern I was discussing.

http://ckdforums.com/showthread.php?s=&threadid=20772

See how the pivots are "side-by-side", and the stop pins are "top and bottom?" Now imagine trying to close the knife handles without being able to clamp down on any stop pins...Whether with the blade open or closed, the handles would be "floating" all over the place....with the blade in tow.

Now imagine the knife in the open position and the stop pin ever-so-slightly off by let's say, a few thousandths...Even that slight deviation will cause the blade to shift significantly to the left or the right of center alignment with the closed handles, depending on which direction the error favored. The open blade tends to look mighty funny if it's not properly lined up with the handles when they're fully closed.

Hope that's clear and you can now understand why the need for precise critical drilling for those stop pins.


Dennis Greenbaum

Yeah Baby!


PS. Ray- I do hope you took my previous "By a kit" as the good natured jest for which it was intended...

[titaniumdoctor]

Dennis,

I am a toolmaker, and when we need a particular set of holes drilled on something that needs the utmost of persicion we drill our holes before we cut the part. In other words, before you cut out your blade blank to shape, mill all four edges square, and establish a "0" corner. You will be working of this "0" corner for all four holes.Figure out where you need your four holes and the distance between all four. Using your digital read out on your mill (if you have one, If not you'll have to use the increments on the mill hand cranks) move to your four spots where the holes are to be drilled measuring off of your zero corner. This will bring you within tenths of a thousanth between all four holes. And the runout on the mill won't matter because it will be affecting all four holes equally. Now you can cut out your blade shape and be assured that all of your holes are on location. Digital readout makes this process 100 times easier and really is worth the couple hundred bucks. Also a good test indicator to tram the head of your mill and indicate your workpiece to the table is a must as you know. I live by my interapid indicator.

Good luck!

[Kevin Wilkins]

I've found ebay to be the best place to buy digital and analog dial indicators.

[Don Robinson]

Dennis, here are the steps to get your holes in alignment.

1. Make the blade. The shape and profile must be finished, but not yet heat treated.

2. Center drill, drill, and ream the two pivot pins for the seperate handle scales. (4 pieces) Stack them all up on top of each other, clamp, center drill, drill, and ream. The pivot must be centered on the scales from side to side, because they must close from opposite sides when the blade is opened and closed.

3. Assemble the blade, handles and two pivots.

4. Turn the handles until the blade is inside the handles and line the blade up straight between the handles carefully.

5. Clamp the assembly together.

6. Using a small center drill, line the drill up centered on the seam between the handles at the location you want the stop pin.

7. Spot the hole with the center drill.

8. Drill and ream the hole with a 1/8 or 3/16" reamer.

NOTE: The hole MUST go all the way thru the handles and the blade at the same time, with the blade aligned exactly between and inside the handles.

10. Open the blade and center it between the handles.

11. Clamp the assembly together with the handles closed to gether again.

12. repeat steps 6,7, and 8.

Now you've got 4 holes in the blade, a pivot hole in the handle scales, AND a notch in both sides of each handle that closes on the stop pin, all correctly aligned witheach other.

When open, the stop pin is captured between the handle scales on one side.

When closed, the second stop pin is captured by the notches on the opposite side of the handle scales.

The pins in the blade must be press fitted or peened slightly to keep them in place.

Next, close the assembly, and make the holes for the end swivel clamp.

I know you can take it from there, and finish everything up with your great detail work.

Last of all, publish a picture here, and send me a photograph in the mail. I'll tell everybody I made it.

I'm about finished with my book on making button lock folders. Guess the next will be how to make a butterfly knife.

[Ray Rogers]

I understand about the kit reference, you're turning my own advice back at me. Thing is, I did get a kit but it wasn't the same kit you have. I have also handled some Benchmade balisongs and so now, in this case, my advice would have to be 'get more than one kit' . The point I was trying to make is based on

you can now understand why the need for precise critical drilling for those stop pins

That's only true if you use that design. The terms you use to define a problem determine the direction the solution to the problem will take.. Darrel Ralph is a mchinist of considerable skill and he has a well equipped shop. He described the design of his kit in terms of precise geometry. If you choose to duplicate that design you will need tools and techniques similar to his. That's fine if you have all that but I know you don't. There are other ways to make a tight balisong - ask anyone who owns one of the high end Benchmade models. That doesn't really help you now because you are already committed to Darrel's design but I'm trying to get you - and anyone else reading this in the future - to recognize that the way you define a problem has a lot to do with the solution to the problem.

Look at titaniumdoctor's solution to this issue. It's exactly right from a tool maker's point of view. Right away, he starts talking about using DRO's and other tools that most of us will never own. It is still a correct answer but his definition of the problem relies on being able to make precise measaurements and that forces you to use tools and techniques you don't have.

Now look at Don's answer. Don is a machinist with extensive experience and he could have defined the problem in terms of precise measurement also, but he didn't. Instead, he defined the problem from a mechanical point of view and is able to achieve the same result with very little measuring or precision required.

I'd like to have something to say that would really help with the problem you are currently experienceing but I don't think I can. The other answers given here are probably going to be of more use right now. But, if I can get you and others who read this to look at these problems a little differently in the first place, it will be easier for you to find solutions in the future. Most of the 'mystery' surrounding common folding knives comes from allowing our view point to become fixated on one small part of the problem when we should be considering the system as a whole, or looking for an alternate design that is within our ability to implement.........

[Don Robinson]

Well, golly gee, Ray!

Thanks.

But I'm also a tool maker, and a tool maker can build most anything without expensive electronics using all manual machines.

[Osprey Guy]

Thanks to everyone!


Jeremy-

A mill is high on my wish list...

Ray and Don-

As always your advice is sage.

I guess I didn't make it very clear that I've already drilled the holes for the blade...but not without considerable trial and error...and lost steel.

I've checked and rechecked the holes and they appear to be very accurate. Ultimately, I wound up drilling the holes prior to profiling the blade...pretty much as Jeremy suggested (making the blade first and then drilling the holes, caused nothing but aggravation...and frustration).

When I first jumped into this thread, I was looking for anything that would further help in my quest for undertanding how to drill an accurate hole. I do believe that my $195 variable speed Delta has one or two inherent problems...not the least of which is the cheap chuck (I do intend on replacing that in the near future). But that aside, most of my problems still stem from extreme lack of any machine shop experience...but I'll get there.

With very little exception, everything I know concerning the shop, my tools, and any and all aspects pertaining to knifemaking, I learned right here in these forums!

Thanks again fellows.


Dennis Greenbaum

Yeah Baby!


PS. Now if I can just work up the courage to finally grind that blade...I do not wish to go through that all over again...at least not on this knife (I'm finally getting anxious to move on to sole authorship).

[Don Robinson]

Dennis, as I said before, the holes should be drilled in the blade and liners at the same time. It's probably too late to salvage that blade.

I don't know how I could make my suggestions more clear to you

Please acknowledge that you understand now how to use a center drill.

[Osprey Guy]

Don-

Remember, this was a kit. The liners were pre-drilled.

I don't know if you're being sarcastic, or if I'm still not making myself clear. I finally do have a profiled, damascus blade with holes that are accurately drilled!

Here's what I said when I first talked about this blade on page 1:

"I finally got the holes drilled accurately, but not after numerous "practice" blades, and ruining a piece of damascus with improperly drilled holes (one was off by a few thousandths). I'll still have to ream the holes after heat treat. (and lighly spot anneal the tang so that I can knock in the stop pins without splitting the hardened steel, all the while using heat sink to protect the blade from the heat)."



It just took me some time to get to this point and I want to save all that aggravation when trying to drill accurately for all future blades.

I do understand about the center drill. Since reading that recommendation I have since purchased one and have already tried using it on some practice blades.


Dennis Greenbaum

Yeah Baby!

[Don Robinson]

OK, try one made from scratch now.

[Ray Rogers]

I'm not surprised you are a tool maker Don. What I want to illustrate is that I know you could have used a machinist - or a tool makers - approach on that question but you didn't. Your answer was appropriate to the skill level, background, and available tools of the person asking the question. That's something we need to keep in mind when answering questions on these forums ........

[Osprey Guy]

When I first decided to make my own blade for this balisong kit, Darrel Ralph suggested I use the existing, hardened blade as a template. Taking his advice I was able to determine where to drill the holes...but I still had some problems.

First, was the orientation of those holes to the blade, which was of my design. With my first attempt, I ended up with the blade somewhat cockeyed to the handles...and worse still, the holes were still not perfect. (My original design called for a dagger...Several blades later, including an expensive piece of damascus, and with the holes off by only a couple of thousandths, the point tilted significantly to one side...I eventually opted for the current design, which just happens to be a little more user friendly).

The crux of all my difficulties has been my drilling technique...and my naivite in blade design...particularly a blade for a balisong with all of it's inherent, subtle issues that revolve around the location of the 4 holes...And further exacerbated by my (challenging) embellishment ideas for the blade.

The good news is that it's forced me into putting in a lot of practice time in both drilling and grinding...lots and lots of practice.

Since yesterday, it's already become clear to me that just that one bit of advice to start using a center drill, will go far to help increase my accuracy. What a difference it made with my practice drilling last night!

Thanks again...


Dennis Greenbaum

Yeah Baby!

[Osprey Guy]

Hey Bob Cannon/Webster-


Oooops! This all started out with your question concerning runnout.

I apologize if I "hijacked" your thread. It was of course, quite unintentional.

I sure hope you got a satisfactory answer to your question...


Dennis Greenbaum

Yeah Baby!