Military mount mortise

[notow1]

I was thinking of grinding one of those stepped unibits to use as the mortise bit on a military mount stem. Has Anyone done this? This may be one of My stupid ideas but I would appreciate any feedback, thanks, Norm. I know Premal will say TIAFO and I will but I would like to know if it has been tried before.

[Ratimus]

I'm guessing it would be less work to just grind one from rod stock. Chuck the bar, spin it, go at it with an angle grinder ala Kurt Huhn to get the taper you want, then use said angle grinder to remove 49% of the material from one side.

[sandahlpipe]

The stepped bits won't work for a military mount. You want around 3° taper or it won't stay put. You can either buy one from Steve Norse or maybe make your own if you have a metal lathe.

[Sasquatch]

I would say 3 degrees is maybe pushing the limits, I'm not sure where the exact "drop off" point is, but if you can see the slope on a military bit, it's pushing into the "might fall out" territory. The infamous "Peterson Drop" occurs.

I'd buy a bit if I was making 100 pipes for a club. To do one or two military mounts, it's enough to sand the mortise by hand - you'll fan it out plenty with a rolled up sandpaper. Cut a stem with a tenon that fits the outer part of the mortise, and then knock a little off the front of the tenon. If it's wedge shaped by a few thousandths, it'll lock up.

[LatakiaLover]

Two degrees, not three.

I guarantee you'll be glad you did.

[notow1]

I like Sasquatch's answer so I will try that first. Thanks , Norm.

[caskwith]

My homemade military mount bit is 1.5deg.

[LatakiaLover]

My homemade military mount bit is 1.5deg.

That's actually my personal preference, but being a fixer and not a maker forces me to deal with other people's stuff.

My "two degrees not three" comment was meant as the upper limit for reliability-of-hold, not what I considered ideal.

[PremalChheda]

Another option is to use a tapered reamer. 1.5 to 2 degrees is ideal but 3 degrees will work as well.

[LatakiaLover]

Another option is to use a tapered reamer. 1.5 to 2 degrees is ideal but 3 degrees will work as well.

Depends how you define "work."

Three degrees requires the stem to be inserted with heavier pressure to be secure, which creates a step-ring as the wood in contact with the stem settles and compresses over time and prevents the stem from being seated farther in. The connection can't be tightened with more pressure. Then, as the wood and stem material continue to compress and wear with use the connection finally becomes loose.

I'm sure that individual wood hardness varies enough from specimen to specimen that such a situation doesn't always develop, but I've seen it fair amount over the years. Enough that if I made pipes I'd go with a shallower angle that was secure with less insertion pressure as a design choice from the start. (It isn't as though one angle is more work to cut than another).

[caskwith]

Also when making stems it is better to cut a shallower taper and then sand/file to fit. I made my mortice cutting bit to be 1.5 deg but stayed on the side of caution so it might actually be close to 2deg. When I cut the stem I set the topslide to 1.5 deg or slightly less and then use the sanding stage to not only take out the scratches but also increase the taper ever so slightly until the fit feels nice.

[oklahoma red]

The semantics here is half angle or included angle? Jeremiah's statement of 3 degrees is perfect if talking included angle.

[caskwith]

The semantics here is half angle or included angle? Jeremiah's statement of 3 degrees is perfect if talking included angle.

Very good point!

[sandahlpipe]

My point here is more that the stepped bits you see in the hardware store are more like a 30° angle and I was just meaning to give an outer limit. So 1-2° is probably better. For my mortises, I set the compound to follow the angle of the J. Alan bits and turn the tenons. On my crappy little mini lathe, it looks like 3° but it's not anywhere close to precise.

[andrew]

A mt1 reamer is about 1.43 deg. The total included angle is about 2.86 deg.

[andrew]

The mt0 is also a good choice.

[mightysmurf8201]

I think George should make a military mount pipe for this year's PITH and show us whippersnappers how it's done.

[Oakbear]

I think George should make a military mount pipe for this year's PITH and show us whippersnappers how it's done.

IAWMS.