Uni-loc pin installation
- Thread starter Kim Bye
- Start date
The main thing with the Uni-Loc is to get it in straight and concentric. I have found the following method to be the easiest for me to achieve that.
Center drill and drill a 1/4" hole and tap for the pin. Then use the miniature boring bar and bore for a snug fit to the alignment shoulder. Then bore a little more for a snug fit to the insert pilot. That takes care of the butt and pin installation machining.
For the insert just drill an undersized hole and bore to the correct drill hole size for the tap. Then tap for the insert. Then use the miniature boring bar to bore for snug fit to the alignment shoulder.
It goes without saying that you should use an indicator and make sure the butt and shaft are running true before starting the above process.
Center drill and drill a 1/4" hole and tap for the pin. Then use the miniature boring bar and bore for a snug fit to the alignment shoulder. Then bore a little more for a snug fit to the insert pilot. That takes care of the butt and pin installation machining.
For the insert just drill an undersized hole and bore to the correct drill hole size for the tap. Then tap for the insert. Then use the miniature boring bar to bore for snug fit to the alignment shoulder.
It goes without saying that you should use an indicator and make sure the butt and shaft are running true before starting the above process.
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RBC
Deceased
I like what Chris has already mentioned, but I would add one thing.
The insert has a smaller than normal 7/16-20 thread to attach it into the shaft. If you bore and tap normal sizes for 7/16-20, the thread engagement will be pretty thin. I've seen many pull out because of this.
If you bore slightly smaller, then use a taper tap and don't go all the way to the full threads, you will get a slightly smaller tapped hole and a much better thread engagement. This is how we used to do it when we used a tap. Nowadays we are live threading it on a CNC lathe so we can just program it to the size we want.
The only other thing I would mention is to pay attention to the depth of the pin. Install it per the instructions and you won't run into a shaft fitment issue later on. I've seen them too shallow and a normal shaft won't go all the way down. I've also seen them too deep and only get 1/2 to 1 thread engagement. I suspect that these will either pull the threads out of the insert at some time, or will constantly loosen up during play.
Royce Bunnell
www.obcues.com
The insert has a smaller than normal 7/16-20 thread to attach it into the shaft. If you bore and tap normal sizes for 7/16-20, the thread engagement will be pretty thin. I've seen many pull out because of this.
If you bore slightly smaller, then use a taper tap and don't go all the way to the full threads, you will get a slightly smaller tapped hole and a much better thread engagement. This is how we used to do it when we used a tap. Nowadays we are live threading it on a CNC lathe so we can just program it to the size we want.
The only other thing I would mention is to pay attention to the depth of the pin. Install it per the instructions and you won't run into a shaft fitment issue later on. I've seen them too shallow and a normal shaft won't go all the way down. I've also seen them too deep and only get 1/2 to 1 thread engagement. I suspect that these will either pull the threads out of the insert at some time, or will constantly loosen up during play.
Royce Bunnell
www.obcues.com
RBC
Deceased
Yes, the normal 5/16-14 threads will work.
Actually, you want it more loose than tight.
The easiest thing that can go wrong with the pin install is drill wander. The bottom of that hole, where it's tapped, must be straight. If no, it will push the pin off center and cause it to be crooked.
Royce
The 5/16x14 works. The thread on the bottom of the screw is actually a .276x14. Not really logical but it is what it is. Drill bore drill. Perfect
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Thanks Royce. I drilled the hole a bit tight and had trouble seating the pin, I'll try widening the hole by a fraction and tap again.
I must say that this experience has just increased my contempt for the Uni-Loc design! Overly complicated install and not a very good product in itself.
I'll stick with 3/8-10M and good ol' 5/16-14 for my cues...
The install is pretty easy. Standard 5/16's hole. What are you missing? I know it's not for everyone but certainly not complicated.
Just trying to help.
I should say 5/16 for the shank and 1/4 or F drill for the thread. The shank being snug is more important as the thread is very undersized.
Thanks
I made a few dumies from canvas phenolic just to get the feel for it.I think I got it now
Thanks
I think I got it now
Nice. On the shafts. Do a phenolic plug first. That insert is no good going directly into wood. Snug fit on your bore for them also. Face after you bore, they go in dead nuts straight.
RBC
Deceased
Kim
Actually, you don't want a tight fit for the threaded portion of the screw.
The threads are undersized to give it room. If the hole wanders any at all, the threads will hit on one side, pushing the pin off center. Yes, it will push it off even with the alignment barrel.
By the way, I don't much care for it either, but it is a very well engineered and made product.
Royce
Thanks guys
Awesome. Congrats. Knowing and doing it increases your versatility, as well as your business.