For future birch bark grip builds, I am working out a system in which the rings are all centered and drilled with the correct diameter for the blank before I glue them all up. Tired of enlarging/reaming the glued up grip and having it separate so I have to glue again. That is just wasted time. Want to be able to maximize efficiency in all my builds.

So I need smooth mandrels in sizes not available commercially, like 3/4, 9/16. etc.

I found an old old tap set among my Dad's stuff (passed in 1989).
Never tapped before.
Any advice?
Also, just how difficult is it to turn the tap.
Using steel rods for the mandrels,
I want to be able to screw nuts on to create the clamping pressure.
Also thought of using the old-style wooden clamps and drill holes in the clamp for the mandrel,
Want to be able to just slip the glued and set grip off the mandrel, not twist like you have to with a threaded rod.

Harry T. Bell

Harry,
As long as the rod that you you are tapping is not hardened or tempered steel, it is pretty straight forward to tap a rod.

Just have the tap and rod of the correct matching size. Use a vice to clamp the rod in place. Place the tap onto the end of the rod with tapered end of the tap on the rod first. Use cutting oil of the right kind for the material being tapped. For steel, just common oil will work fine. Start the tap straight and keep it straight. I like to do about 1 turn on the tap and then back it off and clean the threads. This helps to keep the threads running straight and clean. Sometimes you can to several turns before cleaning the thread. When you back up the tap, just to a portion of the turn backing up as you clean out the threads. The object of backing the tap up is to clean out the threads without changing the angle of the tap on the rod.

For larger sizes as you are entertaining, it may make a lot more sense to take your rods to a machine shop and have a good shop turn the threads onto your rod while the rod is in a lathe. This will insure that the threads are true and straight.

It is pretty easy, with a hand held tap to get the threads on the end of the rod crooked.

Another option is to simply use continuous threaded rod. Or, to use long bolts with one end of the bolt threaded. Then, simply chop off the head of the bolt in a metal cutting chop saw.

By the way, you are asking for smooth mandrels for your builds. Threaded rods work just as well. Then, after gluing, just unscrew the rod from the glued up grip.

It is pretty easy to turn threads on small rods, but as the size of the rod goes up in size, the threading of these rods become increasingly difficult.

Also, if you do have some larger taps from your father, be sure that these taps are not pipe taps. Pipe taps use a very tapered thread which will NOT work to put a nut on a rod.

Certainly if I were doing it, I would not be attempting to thread the rod, I would just use the correct sized continuous threaded rod, or a bolt of the appropriate length with threads already in place.

Be safe

Harry,
Another very simple thing to do, is to take a piece of 1/2 inch threaded rod. Use masking tape on the threaded rod, to build it up as needed for a nice fit on the inside of any grip that you are making.

Glue up the grip, put a nut and washer on each end of the threaded rod to compress the glue joints and let dry. When dry, take the nut off one end of the rod, and use a 1/2 inch drill in reverse to remove the mandrel from the glued up grip. Very easy, very simple and very inexpensive.

A 1/2 inch piece of threaded rod is stiff enough for minimal bending and with the threads already in place, you can have your all of your wishes met.

The use of the masking tape does a nice job of covering the threads and to also size the rod as needed for your use. I have used this system for years and it works very well.

I just take the threaded rod and place it next to the blank that I am building. Then, I start putting arbors on the rod, using a caliper to insure that the arbor matches the same spot on the blank. Ream or drill out the grip pieces, coat the pieces with glue and clamp up and let dry.

Be safe

i have a question

Why are they coming apart when reaming them to fit the blank
Glue no good Wrong glue ???
Have not done any yet But if they don't stay together when glued Why bother ???

Bill - willierods.com

A birch bark grip will break unless there is a mandrel, dowel, or a rod blank going through it. Doesn't really "break". The layers of bark separate. I've never had a section come loose where it was glued.
I just love these grips, what can I say?

Roger, you are right. Not only that, but the taps setup for diameters greater than 1/2" will run close to $50-75, as I learned at Lowes this morning.

Thanks for the input. I thought about wrapping the threaded rod with tape, but thought it might make a mess in the bore during removal. I'll use that trick as well. I made a 3/4" steel smooth mandrel today and am using it for a center pin float blank.
I think it's ST1355-MHX. The butt is .67"

I use the threaded rod for and rings to glue I also use rod bond -- Thin coat don't need to load it on
Then I snug them up and kind of roll the unit over say newspaper on a hard surface to line up the rings Saves on shapping Tighten the wing nuts let it sit overnight

When I take it off I just take one wing nut off and tighten the other If you did not load too much glue it should just pop off - with a little turning also

Bill - willierods.com

Harry,
Another way to make the grips is to use a piece of threaded rod that is the size of the smallest ring that you need to have on the grip.
Then, go ahead and bore the rest of the rings or grip pieces to the size of the blank at the station where the ring will be installed.
Then, use a thin layer of glue to adhere the pieces, as Bill suggests. Put a washer on the end of the threaded rod and a nut to secure the pieces. Now, with the nut just starting to get tight, adjust each of the rings so that they are aligned with each other on the outside of each of the rings. This will mean that the bulk of the rings will also be aligned fairly well on the inside.

Let the grip dry. Remove the grip from the threaded rod. If you are using a wood glue, then let the grip dry for another day to insure that the glue on the inside of the grip is dry as well.

Now, go ahead and ream or drill as required for the grip to fit the blank. Finally, now go ahead and use tape as required to size up the threaded rod, to match the bored / drilled out interior of the grip.

Put the grip back on the built up threaded rod and put the nut and washer back on to secure it in place. Put the threaded rod on your lathe and turn the grip as required.

The reason that I am suggesting this order, is that because in the past, I tried using the tape on the rod before gluing and ended up with the grip, glue etc. sticking to each other and causing a mess that was not easily resolved.

But, with the grip glued up, and the grip reamed out - then putting it back on a built up arbor does not cause any grip or tape stuck issues.

I should have pointed this out in my original reply that I do the tape on the arbor = only after reaming out the glued up grip. However, the reaming and or drilling is very minimal since each piece has been reamed to match the blank and only a thin layer of glue was placed on each piece so that there is very little glue that protrudes from the interior of the grip that has to be removed.

Be safe