Drilling clearance hole in tang for cross pin. Am I missing something??

[groy87]

I've recently been installing a 1/8" cross pins in into my hidden tang handles where I would drill the hole in the wood block, clamp the blade into the handle, and would use the pre-existing hole in the block as a guide for a stub end mill to cut through the hardened steel tang. This would yield a good results (alignment wise) where the pin would pull the blade into the handle. That catch is that the process would always open up the hole in the handle leading to gaps between the wood and the pin.

To combat this I decided to drill an oversized hole (5/32) in the tang and will use that to mark where I will drill the 1/8" hole in the block to install the pin. I figured that I can avoid accidentally opening up the hole and clearance in the tang can be accounting for by clamping the handle in the glue up and the epoxy would fill the gaps between the pin and the tang. Yielding a strong joint.

Is this a viable option or am I missing something that will come back to bite me later??

 

[Rick Marchand]

Why not anneal the area of the tang where the pin would be and drill it through after it's glued and cured? That is how I have always done it. No gaps.

or...

Drill your 1/8" hole through the wood block and use then insert your tang, spot the hole location, remove, drill the tang, then install the pin on glue up.

or...

Do what you said you were going to do. That'll work, too.

 

[Natlek]

I drill hole in handle and tang for pin before hardening . Is that not the best solution ?

 

[Rick Marchand]

I drill hole in handle and tang for pin before hardening . Is that not the best solution ?

That wouldn't work for me. I etch and sand a bit after HT. So do you fit your bolsters, guards, spacers, etc... prior to HT?

 

[groy87]

I drill hole in handle and tang for pin before hardening . Is that not the best solution ?

I agree that drilling the hole while the steel is soft would be ideal but I am not set up to make my own blades. I buy them premade from smiths such as Michael Eklund and Paul Strande and make a handle and sheath for the blade. Most of the time the tang along with the blade come in hardened and I have to mill or drill through the hardened metal with a carbide bit. I have yet to try my hand at annealing the metal to soften it but even then my original question still applies . I have been trying different methods recently to see what works best for me but this week hasn't been the best for me in the shop (messed up a sheath, bolster, and final finish ) so I wanted to try and mitigate the risk of adding another screw up to the list lol.

On another note how much material do you usually leave between the hole and the edge of the tang? I usually try to leave at least an 1/8" of material for strength. Most of the blades I've worked with so far are smaller and not designed for chopping so I'm not too concerned but I have been wrong in the past.

 

[Stacy E. Apelt - Bladesmith]

In the scenario you have:

I drill that handle initially with a bit half the size of the pin (eg., 1/16" for a 1/8" pin). Mark the tang with the drill bit guided by this hole. Drill out the tang hole 50% larger than the pin if the tang allows it (3/16" for an 1/8" pin). The excess room in the tang is not as big as it sounds, and prevents alignment problems in glue-up. Check that all aligns well with a 1/16" pin, and if it does, glue up the handle. Once the resin has cured for 24 hours, re-drill the handle with the correct size bit for the rivet, and epoxy in the rivet.

If you want really precise fitting holes with no tear-out, use a bit a little smaller than the pin, followed by a reamer about .005" larger than the pin. This will leave a perfectly round and smooth hole for the pin.