Looking for ideas for an action testing jig

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BCRider

BCRider

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I'm wondering if there's anything out there for holding pins in position that match the relationship of the pins in various actions.

The idea is to simulate the pin positions in the frame but outside where I can see any issues and gauge things and monitor progress.

I know of the trick of putting the pins through on the outside of the frame but this often results in stuff being in the way such as on a Colt style single action revolver or the pins are sloppy in the holes so the parts simply do not fit the same as they do in the gun when the pins are supported on both sides.

So I'm looking at making something that will allow me to measure and position pins of suitable size accurately centered and held rigidly vertical as they would be in the trigger group so I can work on the parts and gauge my progress more accurately.

Or do most of you that do such things simply make up a custom block for each style of gun you work with for when you need this sort of tool?
 
That's the idea that I'm after but those are very specific to each style.

My collection is a trifle varied and while the custom extended pins for the 1911 would be good for that gun (I've got four 1911's) it's still only for 1911's.

For example the latest job is tuning up the trigger/sear and hammer notches on my Hopkins & Allen underhammer repro done by Numerich. So I'm looking for a jig to replicate the hole spacing for those two shafts. And needless to say there's nothing like this around so I'm considering the idea of a jig which is a little more universal so it'll apply to a range of my guns when I tinker with them.
 
Try Power Custom, he has adapters to a master jig for trigger actions as well as a universal stoning fixture from actions. Look under gunsmith tools. http://powercustom.com

Brownells also has similar products and may carry Ron Power's stuff as well.
 
Can you not just get longer pins or tool steel drill rod in the correct diameter and make your own pins, any length you want?
 
There was once a universal hammer/sear alignment jig.
It was a plate with one fixed hole and a block with another hole sliding in a groove.
Pins with one end to fit the holes in the jig and the other end to fit a specific gun part were available.
Plug in the appropriate pins for your gun, set the movable block for the correct spacing, and study the engagement.
I haven't seen it listed in Brownells for a long time, though.
 
There are bench blocks made with various hole positions, but the major use is for the 1911. I don't know of any blocks made for newer or less common pistols like the Glock, H&K, Beretta, etc.

Jim
 
Boomboom, it appears that he's not offering that specific jig any longer. Found some other neat ideas though. Thanks for the link!

Jmorris, yeah, I'll be making my own pins to suit. But while it would work in THIS case in others, such as SAA's, parts of the gun such as the recoil shield get in the way. So I need some way of duplicating a specific gun's pin locations. The sizes of pins isn't an issue. I can turn whatever I need if I don't have round stock of the right diameter. It's the jig to hold the pins that I need to make or buy.

Jim Watson, that's exactly the sort of thing I'm considering. But something where I can position a few separate pins on some sort of slotted arms and then insert the pin ends into the holes in the frame or receivers and then lock things in place.

Looks like I'll have to fire up the metal working shop and make something up. I'll post what I build for the amusement of all.... :D An idea of what I'm going to do is gelling as I type.
 
Good luck!

You are biting off a big chunk there my friend!!

So many unusual lock-work configurations, with various internal supports in different actions, I wouldn't even know where to start for a 'universal jig' fixture.

The Ron Power sear jig was as close to anything like that I ever seen in 50+ years of gun fixing.

And it was far from universal.

rc
 
If I needed two parallel rods I would like just take some thing and drill two holes in it the diameter I needed and insert the rods. I could do that faster than I could find a previously made fixture likely.

If I just had to have something that could hold various diameter pins parallel at different distances apart, I guess I would use two chucks and have one in a slotted hole so I could change CL distance.

IMG_20151120_093222_929_zpsaxq1wqju.jpg
 
Looking forward to seeing it. You may have a new business on your hands from people wanting copies.
 
That is it, although I would only make the slot wided enough for the bolt holding the chuck in place.

That was just the first humk of metal I picked up that had a slot in it.
 
Oh trust me, I know that there's no such thing as a truly "Universal" jig. Something will always be found that is different. And something like the sliding fit of a 1911 disconnector is always going to mess up the works. Two pins will at least allow me to work on the lion's share of a sear and hammer setups. And a holder that handles three pins will allow me to duplicate all three pins in a SAA and early Colt and Remington cap and ball revolvers. So that's the standard I want to achieve.

It'll be a slight variation on jmorris' sliding chuck idea that allows me to hold THREE pins in place at one time. It'll also be the sort of jig that any hobbyist or gunsmith can make really easily.... it'll have to be since I'm that exact same sort of hobbyist.... :D

I think I'm going with something other than the drill chucks simply because those would greatly limit how close I can locate the pins. Even that slick little Dremel accessory chuck would impose too much of a spacing limit when two of them need to butt up against each other.

The weekend is already booked but I need to make SOMETHING for this present tuning project. So I think I have my first few days of next week planned for making this jig.
 
Thanks jmorris (pix did not come up on my tablet when I made the comment) and looking forward to seeing yours bcrider. jmorris, what size chuck did you use if you do not mind me asking and where did you buy it?
 
They are just the first chucks I could get my hands on 2 are for a burgmaster turret drill the other for a dremel tool.
 
The chucks seems like a great idea at first until we stop to realize how big they are. The chucks would simply not work for the pin spacing to replicate that of a 1911 for example. And they won't allow for the pin spacing on a SAA revolver either. So while it served the purpose of demonstrating the concept it's a non starter of an idea for many situations.

All I can say is wait for it. If my design idea works out I'll be able to hold the little teensy pins from a Ruger Mk III by their last 1/8" of length firmly enough that I can work with them.

If I can manage this so I actually use the pins from the specific gun then I know it's holding the parts in the same way as the gun instead of wondering if the better or worse fit of some replacement pins for the jig is causing an issue.

All I can say for now in my best imitation of a British drill sergeant's voice is "WAIT FER IT YOU MAGGOTS! ! ! " :D
 
So while it served the purpose of demonstrating the concept it's a non starter of an idea for many situations.
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That was kind of my point at the beginning of #10. I can grab a hunk of steel, aluminum or plastic and drill two holes in it for any diameter pin almost as fast as I posted this post and a lot faster than it took to take and upload the photo of the chuck concept.

You could drill out socket head cap screws for the diameter pins you wanted and still use the slot idea but when it takes more effort to build an adjustable fixture that it would to build individual fixtures for all of your needs, I don't see the point.
 
Teaser time :D

I noodled around in my CAD program last night for a while and came up with a bunch of really hard and fussy to machine methods for making a shallow angle "V" and microscopic finger clamps to hold the pins.

Then I had a "EUREKA" moment and realized that if I make up a 90° "V" single point broaching cutter I can drill a simple round hole then extend it on one side to a "V". A small set screw with a rounded and polished nose pushes the pin into the apex of the "V" and VOILIN! or VOILA! or whatever it is that they say..... :D

Making a little V cutter from some drill rod isn't a big deal for me. And I've already done this when I made up a similar 120° broaching cutter for another job. I found that shaving off up to .005 at a time early on and around .002 for the wider cuts didn't result in all that much of a cutting load.

If I set the nose clearance angle just right the cutter will wedge into the work as much as the work tries to push it back away from the cut. I'll set up and use my little test guage on the back spine on a trial cut or two to adjust the front rake so these two loads cancel and the result should be a nice "V" that is truly vertical to within a very small angle.
 
but when it takes more effort to build an adjustable fixture that it would to build individual fixtures for all of your needs, I don't see the point.
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You are 110% right. But I've got enough guns that I want to tune or otherwise examine that I feel I'll save time in the long run.

If nothing else I'd need to make up something for measuring the hole spacing. And yes, I know of the methods that only require a set of calipers and you measure the inside and outside dimensions and then average them. But if there's three pins in a specific placement then I need to do a lot more measuring and laying out. But if I can put the right size pins into holders and then set the frame down over the pins to locate them and then snug the holders down that last little bit that's a lot less time than trying to match up and drill custom jigs for each and every gun.

At least that's my theory.... :D I may need to take a sober second look at this. But then if I proceed I'd have something new and shiny for the shop!

Oh the pain and confusion.... :D
 
IF one had detailed engineering drawings of each gun, and precision machinery to drill accurately, and drill bits and pins in the right (metric and English) sizes, and blocks of steel that can be hardened without warping, and .... You get the picture.

You really can't even depend on using a gun or its parts as the masters, as one particular gun might be out of spec.

Jim
 
I noodled around in my CAD program last night for a while and came up with a bunch of really hard and fussy to machine methods for making a shallow angle "V" and microscopic finger clamps to hold the pins.

Then I had a "EUREKA" moment and realized that if I make up a 90° "V" single point broaching cutter I can drill a simple round hole then extend it on one side to a "V". A small set screw with a rounded and polished nose pushes the pin into the apex of the "V" and VOILIN! or VOILA! or whatever it is that they say.....

Making a little V cutter from some drill rod isn't a big deal for me. And I've already done this when I made up a similar 120° broaching cutter for another job. I found that shaving off up to .005 at a time early on and around .002 for the wider cuts didn't result in all that much of a cutting load.

If I set the nose clearance angle just right the cutter will wedge into the work as much as the work tries to push it back away from the cut. I'll set up and use my little test guage on the back spine on a trial cut or two to adjust the front rake so these two loads cancel and the result should be a nice "V" that is truly vertical to within a very small angle.
Click to expand...

I might be missing something but that just gets you something that will hold different diameter pin, on different center line BTW. Thought you needed something that would hold different diameter pins different distances from one another.
 
For measuring hole spacing I use pointed edge finders or indicators (depending on exactly how close I need to be in conjunction with my mill/DRO.

I suppose the center gauge conversions would work too but I would make a "Standard" for them myself.

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Z17-s0fo5oy.jpg
 
You really can't even depend on using a gun or its parts as the masters, as one particular gun might be out of spec.

Jim
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Unless you are trying to return a gun to spec or take a spec gun and bring it to center of spec, seems like it would be good to use the particular gun being worked on as the master.
 
I would be using the frame of the specific gun I'm working on at the time to locate the pins in any event. I'm in this as a hobby so I only have a limited number of guns I'd be doing. And in the case of multiples such as my four 1911's I'd check the jig from one against another frame before I'd trust it. Like was said there's tolerances in everything and if I'm trying to be specific then I need to base the work off the frame in question if I'm doing something fussy like honing the angles of sear and hammer for a tighter and lighter break.

I decided to just go with a bit of scrap and a couple of pins in this case. The H&A underhammer action only needs two holes in a flat plate.

First time I've used my transfer punch set in anger too ! ! ! ! :D

The idea of a jig that I can use to position up to three pins is still something I'd like to do. But for now there's more pressing items on the agenda. But winter and a lot of rainy days are ahead so it might just happen soon. I'll update this thread when it happens.
 
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