Our Famous "Pin Kit"
Our Famous "Pin Kit"
Nails Made of Mild Steel that Grip Like a Rivet
These extra durable and easy to strike and set nails can be placed on adjoining lug socket (crisscrossed) and still be struck and set.
Tapered Square Nails and two Correct # Number drills make Tight Pre-Pinning a cinch will grip even if the hole is uneven or enlarged.
Used by Frame Makers for over a hundred years throughout the World.
1/2 pound of Tapered Square Nails
2 Cobalt Short Flute Drill Bits
The Fine Old Art of Pinning
The group of frame builders from my father's generation used to brag that their frames were fit together so well they only needed to be pinned and you could get on one and take it for a ride. That was many years ago, but the fact is: frames have been pinned since the beginning. Many builders are known for never using a frame fixture, they just used a straight edge, a hook to hang the frame from and high quality PINS.
To begin the pinning process properly you must start before most of the construction of the frame has begun. This is often overlooked, but it is very important is to determine where you are going to pin before you even start cutting your lugs. This is even more crucial on intricately cut lugs, attempting to drill them after preparation can be difficult and might cause damage.
Pin locations can dramatically influence the ability to maintain frame alignment during heat-up. Rule of thumb, each socket should have at least two opposing pins if possible. If the socket itself is fairly loose on the tube, more pins may be needed. Some lugs may fit very tight, or have angles that are very close to your final plan. These types of lugs, as well as some seat lugs, may only need a single nail top-center in the back (near the crotch) to hold the top tube.
Locate the positions where you will place your pins.
Use the drill bit provided (the one with the slanted bevel cut into the chuck end of the drill bit) to drill the lug.
De-burr the holes inside and out.
Proceed with the frame pre-construction.
After the joining preparations are completed, you should then flux the joint like you are ready to braze.
Use the second drill bit provided (the smaller one without the bevel cut into it) to drill through the first holes while holding the joint in alignment. Be extremely careful to just penetrate the tubing and not go all the way through both sides of the tube.
If you’ve chosen to use opposing nails, which is my preference, insert a nail in each hole and very gently tap them with a small hammer. Do not set one side all the way first.
Once you are satisfied that the nail is beginning to grip, tap them in firmly. Knowing when the pin is fully set takes a little practice. The pin should not wiggle, be quite rigid and twang when you tweak it.
Don’t forget this step. Liberally reflux the pin and the area around it.
Braze the joint and allow it to cool completely.
Make sure you don’t get hasty and start cutting the pins before cool down.
Cut the pins as close to the lug as you can. Make sure you don’t twist or bend the pins.
File and sand the pins flush with the surface of the lug.
At this time you want to verify that the joining material has fully surrounded the pin. If there are any voids, you didn’t flow your joint properly during joining. To fix this, you can flow a little of the rod to the pin. Be careful to never direct your torch directly to the pin or overheat it. That will cause the pin to char and not become part of the structure.
Inside Finishing with a rotary tool
I use a Dremel with two 409 wheels piggy backed on the arbor. Most sanding drums on most rotary tools will work.
Insert a rotary tool into the head or seat tube.
Sand the pin until it is flush with the inside of the tube.
Inside Finishing with a cold chisel
An alternate method of getting started on the inside removal requires a bit more skill, and could cause damage if done improperly. The procedure involves removing most of the pin tip protruding through the tube with a small and very sharp cold chisel. I curved mine so that it hugs the inner wall of the tube.
Use a cold chisel to remove the majority of the pin.
Sand or file the remainder of the pin until it is flush with the inside of the tube.
The lugs used in the illustrations are "Newvex" by Richard Sachs.