question on the button lock

[SVanderkolff]

Don
I am once again attempting to build the button lock. I am doing it as an auto but that should not change the problem. The button itself keeps popping through the liner and blade. It will not stay in. There seems to be just enough room for the bottom of the button to move around and come loose and pop through the top bolster. There is no extra clearance around the button on the top bolster, the button is the exact measurements on your diagram. The only thing different is that my liners are .064 as opposed to the .090 that you recommend. Could that make the difference? What is the solution? I have thought of makin ghte bottom of the button wider so .250 for th etop of the button and .30 for the bottom and then adjust the liner and bolster spaces to fit. Could that be a solution?
Any help would be greatly apprciated.
Thanks
Steve

[Don Robinson]

Your button is moving into the blade notch more than the depth of your liner, so it all comes loose. This design requires the thicker liners just to prevent what is happening.

When you put the bevel on one side of the 1/4" dia. at the groove, you made the bevel enter the blade notch far enough that the button can come all the way out of the right side liner.

Solution? Either a new button with a shorter bevel, a longer 1/4" dia. as you suggest, or a new liner.

[SVanderkolff]

Don
I tried making a new button, in fact I have made three new buttons but cannot get the problem to go away. I think the problem lies in trying to get the tolerances exact between the liners, the buttons and the blade. So I am starting all over. This time I am going to try a .250 bottom to the button and a .1875 top button with the drill thru onthe blade and the top liner being the .1875. I am using a taig lathe for the buttons so can get quite accurate on the button demensions where as both my drill presses and my mill seem to generate a fair bit of wobble when drilling. Is there any reason this can't work?
Thanks again for the help.
Steve

[Don Robinson]

Let's be sure you and I are on the same page, Steve. On your page 2 of the design, does it say in the box "Rev.06/09" If so, you have the latest revision.

Now, properly made, it's impossible for the button to slip into the blade notch when both liners are in place because the notch is smaller than the button.

The button is .250 dia. the notch is supposed to be a reamed .242 diameter. Therefore, with both the liners and the blade in place and if everything is right what you describe isn't possible unless something is out of alignment or you have sloppy fits.

Are you using a center drill to spot each hole before drilling? If not, then your drills are walking out of location. A reamer will simply follow the drilled hole.

Are you stacking the liners and blade up on a flat plate while you locate, drill and ream all the holes? The liners must be drilled and reamed while they are stacked together in order for the holes to match at assembly. Nothing else will work properly.

Did you leave enough material on the heel of the blade in order to have material for a full hole when you drill and ream the button notches in the blade? You can't drill or ream a partial hole.

Do you have the Construction Notes on page 7?

This design is the most difficult of all my designs for people who don't have a machine shop background to understand and do successfully.

Each step must be done properly, fitting matching parts as you go.

You must have a properly aligned spindle to succeed. You mentioned drills wobbling. That is simply unacceptable. Makes me wonder if you're using a center drill.

By the way, people today are calling a center drill a "combination drill/countersink". That just shows the ignorance of the person writing the description. So if you look for one in a catalog you'll have to look for the "combination drill/countersink". You need a small one for knifemaking.

I hope this helps you diagnose your problem. You need to replace that liner with a thicker one.

Let me know if I can help you further.

[Don Robinson]

Originally Posted by SVanderkolff

So I am starting all over. This time I am going to try a .250 bottom to the button and a .1875 top button with the drill thru onthe blade and the top liner being the .1875.
Steve

This is a major problem. The notch in the blade must be smaller than the button diameter on each end.

[SVanderkolff]

Don
The drawings I have are labelled as Rev .6 05/28/06. There are no construction notes, it only has 6 pages.
What is a center drill or combination drill/countersink. I use a center punch to mark the holes but it sounds like you are describing something different.
Here is the sequence of events that I am using, please correct where necessary.
Stack the two liners together, drill a 3/32 hole for the pivot.
Mark the blade and drill a 3/32 pivot hole.
Mark one liner with center punch for position of the button hole.
Insert pivot and stack all three together. Liner, blade then liner with the blade in the closed position. AT this point the liners are rough shaped and the blade is a large oversized chunk of steel.
Clamp together with vice grip.
Drill undersized hole for .242 hole blade is in closed position.
Rotate the blade to the open position, clamp blade in place between liners. (hold it, how will this keep the two liners lined up?)
Drill undersized hole for the .242 hole in blade in open position
Unclamp
ream undersized .242 hole in blade to .242
ream liner holes to .250

Does that sound right?

Don, thank you for all your patience.
Steve

[SVanderkolff]

Don
I just figured out that a center drill for use in starting a hole is the same piece that I have for use on my lathe. I have centre drills. I think if I set it up properly on my mill then it should make this whole process much simpler although I am not sure how I will line everything up exactly for the drilling of the blade in the open position.
Steve

[Don Robinson]

Originally Posted by SVanderkolff

Don
The drawings I have are labelled as Rev .6 05/28/06. There are no construction notes, it only has 6 pages.


I'll send you a newer revision if you'll give me your mailing address. But you'll have to start all over and use the instructions provided.


What is a center drill or combination drill/countersink. I use a center punch to mark the holes but it sounds like you are describing something different.


Never ever use a center punch for anything.



Here is the sequence of events that I am using, please correct where necessary.
Stack the two liners together, drill a 3/32 hole for the pivot.
Mark the blade and drill a 3/32 pivot hole.
Mark one liner with center punch for position of the button hole.
Insert pivot and stack all three together. Liner, blade then liner with the blade in the closed position. AT this point the liners are rough shaped and the blade is a large oversized chunk of steel.
Clamp together with vice grip.
Drill undersized hole for .242 hole blade is in closed position.
Rotate the blade to the open position, clamp blade in place between liners. (hold it, how will this keep the two liners lined up?)
Drill undersized hole for the .242 hole in blade in open position
Unclamp
ream undersized .242 hole in blade to .242
ream liner holes to .250

Does that sound right?


No, wait for the new design. You can't make one or two parts separately. All the pieces must be stacked up together on a tooling plate. Each hole must be drilled and reamed thru all the pieces together including the tooling plate. The two liners are on the bottom of the stack, then the blade and backspring.


Don, thank you for all your patience.
Steve

You're wecome, Steve. Be patient, now.

[SVanderkolff]

Don
My mailing address is:
Steve Vanderkolff
5 Jonathan Crescent
P O Box 472
Mildmay, Ontario
N0G 2J0

Is there any way you can scan them and email them?

By the Way, what is a tooling plate? Dumb Question?

Thanks
Steve

[Don Robinson]

Check your email. I've sent them.

A "tooling plate" is a sacrificial plate used to build something on. Any piece of flat steel at least 1/8" thick that can be used under the stack on your milling machine.

A piece of flat ground 01 about 1/4" x 3" x 10" would be ideal, but any flat piece of steel will work.