Milling stop pin holes

Peter Atwood

Peter Atwood

Joined
Oct 26, 2000
Messages
2,468
OK, here's a question that got lost in the folder problems sound off thread...

How do you go about getting those pesky square bottomed stop pin holes to line up from side to side. I understand that they should be started with a drill bit and finished with an endmill, but how to get them from one side to the other without being out of alignment. I'm guessing that measuring would be one way but would making a thin paper template that you transfer to the other side work better?

Of course you can always take the Mad Max approach and use the thumbstud for a stop pin but that probably presents its own set of problems...right Darrel?
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Peter Atwood

email: fountainman@hotmail.com
 
OK, I'll take a crack at this question. If you have a mill you can create a index plate that references off the pivot and one other point further back on the handle scale; use dowel pins and a holddown clamp. Set your mill to the stop pin hole location, and you're set to go. You can do two or two thousand as long as you don't change the head location.
 
SOunds good Andrew, but what about if you don't have a mill and are just using a drill press. I know it's tough to get accuracy with a middle of the road Delta drill press, but that's what I've got.

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Peter Atwood

email: fountainman@hotmail.com
 
Peter:

I realize every maker has his own methods, but here's how I approach machining stop pin holes:

1. Make sure your drill press table (or work surface) is absolutely square to the spindle by inerting a precision rod into the chuck and checking for gaps with a precision square. (A drill blank or reamer blank will work well as a "precision rod.")

2. Centerpunch the locations and drill the holes for the pivot, stop pin, and frame screws in one liner only.

3. Clamp the two liners together and match drill the pivot hole. (Ream as necessary.*) Install the pivot through both liners.

4. Clamp both liners together and match drill the frame screw holes, using the proper tap drill size. Tap the frame screw holes in one liner, and open the holes up to the fastener body diameter in the other liner. Assemble the frame screws through both liners.

5. With the pivot and frame screws installed, drill the stop pin hole. (Ream as necessary.*)

*Depending on what type of hardware you're using, you will follow the drilling sequence with a reaming sequence for both the pivot and the stop pin. - That is, if you are press fitting the pivot and stop pin into the lock side liner.

Another tip is to leave extra material on the blade where the stop pin will contact the blade in the open and closed positions. You can then grind these areas to finish fitting the blade to your frame.

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Tom Anderson
Hand Crafted Knives


www.andersoncustomknives.com

[This message has been edited by Tom Anderson (edited 05-11-2001).]
 
On my first folders I'm making shouldered stop pins using my little lathe. This allows me to just ream the hole in the frame and thats that. I can also adjust the lenght of the pin between the shoulders to the exact thickness of the blade and bushings. Also, I can either tap the pins for screws or leave them plain depending on the design.

Neil

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Talonite......Stellite
Hand Made Knives..High Tech Materials
blackwoodknives.com
 
I use a drilling template made out of fully hardened D2 steel. This template allows me to drill all of my holes in the right place every time. I can drill all of the holes for one liner or frame side and they will match the holes in the other liner or frame side. All you have to do is clamp the template to the liner and drill with the appropriate drill.

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Barry
Jones Knives
"NEW Knives"
http://albums.photopoint.com/j/AlbumIndex?u=126319&a=5922856&f=0
"For DUTY and HUMANITY!"
Curly, Moe, & Larry
 
Peter, I can relate to using a middle of the road Delta drill press. I'm including a picture to show my cross vise with a drilling platform that I made from precision ground stock. I dialed the table in and was able to get very good accuracy. With a set up like this you can drill, ream, or tap holes in the drilling platform to meet the requirements of whatever project you are working on.

View


[This message has been edited by Andrew McLurkin (edited 05-11-2001).]
 
It is interesting to see the different ways people approach this problem. I like the precision required to do the press fit method that Tom describes, but the shouldered pin method of Dr. Lathe sounds equally intriguing. Thank you Andrew for posting the Delta setup, makes me feel a little better. I do own a crossvise so just need a little help figuring out how to use it properly. This business of precision machining does not come easily to those of us who are used to down and dirty freewheeling approaches to projects!

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Peter Atwood

email: fountainman@hotmail.com
 
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