What's the best way to secure a slipfit 1/8" steel gage pin into blind-hole steel?

[cazclocker]

I'm making a very small fixture for use with my watchmaker's lathe.
What would be the best way to permanently secure a steel 1/8" gage pin, inserted into a blind hole drilled/reamed into a piece of 1144 stressproof?
The gage pin is a Vermont Gage, I don't know what kind of steel it is.
The blind hole is only 3/8" deep; the pin is fully inserted and the fit is a nice slip fit.

At first I was thinking about dropping a little bit of Tix solder (chopped up into little bits) into the blind hole, and pushing the pin inside the hole. Then heating up the steel piece until the Tix melts.

Then I thought Loctite might do it. But which forumua? Most Loctite products depend on a little bit of clearance so there's somewhere for the Loctite to solidify. In my case, the only clearance would be at the very bottom where the 135-degree point of the #31 pilot drill left a tiny cone-shaped void.

I'm looking for strength of bond & permanence. I suppose I could cross-drill for a tiny taper pin.

 

[ChazzC]

I'm making a very small fixture for use with my watchmaker's lathe.
What would be the best way to permanently secure a steel 1/8" gage pin, inserted into a blind hole drilled/reamed into a piece of 1144 stressproof?
The gage pin is a Vermont Gage, I don't know what kind of steel it is.
The blind hole is only 3/8" deep; the pin is fully inserted and the fit is a nice slip fit.

At first I was thinking about dropping a little bit of Tix solder (chopped up into little bits) into the blind hole, and pushing the pin inside the hole. Then heating up the steel piece until the Tix melts.

Then I thought Loctite might do it. But which forumua? Most Loctite products depend on a little bit of clearance so there's somewhere for the Loctite to solidify. In my case, the only clearance would be at the very bottom where the 135-degree point of the #31 pilot drill left a tiny cone-shaped void.

I'm looking for strength of bond & permanence. I suppose I could cross-drill for a tiny taper pin.

Loctite Retainer series:

 

[WobblyHand]

A drop of super glue? I'm sure you can get some fancy Loctite that's perfect, but super glue works pretty well too. I super glued a 1/4" shaft into a cast iron flywheel, to allow machining the flywheel. The glue is still holding fast in my completed gyro. I used a slip fit, plus a drop of super glue.

 

[dbb-the-bruce]

Loctite or even superglue if you don't have loctite and are in a hurry.
You say strength of bond and permanence - but it's also a question of what type of forces it needs to resist.

Depending on what the use case is, I'd even consider a very slight mechanical deformation like a dimple very close to the hole after the pin is in place and hone the surface around the pin after if needed.

 

[WobblyHand]

You can accelerate the curing of super glue by lightly dusting with baking soda. Literally the tiniest amount will start the cure. On the order of milligrams. I take a tiny pinch of baking soda and let a tiny bit fall on to the liquid. Bam, it hardens.

 

[Nutfarmer]

Locating dowel pins in a blind hole are normally press fit with a threaded hole in the center of the dowel pin. The threaded hole is so the pin can be removed if needed. If you have ever had a dowel pin stuck in a blind hole you will understand. If the hole is already a slip fit and lock tight is used heat will cause the lock tight to release.

 

[cazclocker]

Loctite Retainer series:

That's a good reference. There are so many kinds of Loctite it makes my head spin. At first I thought 635 or 680 was the ticket, because they both say they're for slip fits. But then I looked at the category labels to the left of the product numbers - they say Loose Fitting Parts. I don't get it.

A drop of super glue? I'm sure you can get some fancy Loctite that's perfect, but super glue works pretty well too. I super glued a 1/4" shaft into a cast iron flywheel, to allow machining the flywheel. The glue is still holding fast in my completed gyro. I used a slip fit, plus a drop of super glue.

Yeah, I was wondering about maybe a drop of a good quality superglue. There's a YouTube channel called Project Farm. The guy finds all these various products and tests various brands of the same product to see which one is the "best". He did a super glue video about a year ago. I can't remember which one he said is the best.

Loctite or even superglue if you don't have loctite and are in a hurry.
You say strength of bond and permanence - but it's also a question of what type of forces it needs to resist.

Depending on what the use case is, I'd even consider a very slight mechanical deformation like a dimple very close to the hole after the pin is in place and hone the surface around the pin after if needed.

That's a fair observation - actually, the forces I'm intending to subject it to are parallel to the blind hole & gage pin. That is to say, the force will be as if I was trying to push the pin even harder into the steel piece's blind hole. It won't be rotational at all. It's a goofy idea, but I'm making a miniature tap follower for my watchmaker's lathe. I made an alternate tailstock runner that has a 1"-deep blind hole with 3 locking grub screws. It's used for my carbide PCB drill bits, which all have 0.125" shanks. I intend to use my newfangled gizmo to hold a given tap's butt end in a 90-degree divot on the side opposite the gage pin, which will be locked into my tailstock.

I like the idea of making a slight dimple around the face of my steel piece (which is just a 0.300"-OD cylinder, 0.4375" long) that receives the gage pin. I used to use that technique to reduce the diameter of pivot holes in clock plates. I only did it a handful of times, and I actually made a series of six dimples around the perimeter of the pivot hole. Each dimple was made so lightly it was hardly visible. A light buff with some 1500-grit emery paper and bingo - perfect hole and nobody could tell!

You can accelerate the curing of super glue by lightly dusting with baking soda. Literally the tiniest amount will start the cure. On the order of milligrams. I take a tiny pinch of baking soda and let a tiny bit fall on to the liquid. Bam, it hardens.

Yeah, that's a neat trick. I learned about that some years ago. I don't use it often, but it sure is amazingly effective.

Locating dowel pins in a blind hole are normally press fit with a threaded hole in the center of the dowel pin. The threaded hole is so the pin can be removed if needed. If you have ever had a dowel pin stuck in a blind hole you will understand. If the hole is already a slip fit and lock tight is used heat will cause the lock tight to release.

I forgot about the tendency of superglue to release under heat - my intended usage shouldn't create any heat, but I guess anything can happen.

 

[Asm109]

If you don't need a press to install the gage pin, it IS a slip fit. Use the Loctitie.

 

[Deleted member 69715]

I've used Loctite 609 for things I want to stay secured. Good stuff. It seems to "wick" into the joining.
Whatever you wind up using good luck!

 

[RJSakowski]

I have used cyanoacrylate to secure a drill bit to an extension shank. I neck down the drill and drill a mating hole in the extension. A few drops of cyanoacrylate in the hole and a rapid assembly and it's secure, able to withstand the drilling torque.