This is my very first question on this forum, and furthermore I'm french and not very used to write in english!
I'd like to taper the tenon in order to reduce the condensation. So I'd like to know what is the best shape I have to give to the tenon. For instance, what is the best slope i have to give when i dig the tenon ?
I imagined that the best was a deep tapered tenon, but i 've seen some on handmade pipes that wasn't so.
:dunno:
Your exact answer is unknowable. The perfect slope for your pipe is the one that matches the end of your mortise bit. That way the slope allows the tenon to fit flush with the mortise end. The moisture is probably caused by a gap in the mortise/tenon area or a diameter change between the tobacco chamber and your mouth. If you're getting a lot of moisture my bet is on the first option. Which means that you could slope the end of the tenon to meet the shape of the end of your mortise. But I would also bet that your tenon is not long enough to begin with, in which case the problem is different still.
So, the short answer is that the slope of the tenon should be the same as the slope of the mortise end because the two should join in order to avoid a gap between the mortise and tenon airways.
I think that you are asking about funnelling the INLET of the tenon, rather than tapering the tenon (outside) itself.
If I am correct, then the easiest way to do this is just to take some sandpaper, maybe 220 grit, cut off a square that is 3"x3" or so, and fold it like you would a letter -- two folds dividing the paper into thirds. Make it so the sanding surface is outside so that you have a 1"x3" strip that is rough on both sides. Then roll the sand paper so that it makes a cone. You can stick this cone into the end of the tenon and twist. Keep twisting until you have a nice smooth taper INSIDE the tenon. You can step up to higher grits to smooth out the surface further.
Sure, it helps me : I want to funnel the inlet of the tenon, (my english is a bit poor), and I'm going to try with sandpaper.
But do I need to go very deep (as deep as i can) in my funnelling or do I have to roll on just a few mm inside the tenon ? In fact my question is : if there exist a gap in the mortise/tenon area, what can i do to reduce the moisture ?
Thank you so much Tyler, I think I'm gonna spend my nights on this forum !
You can always go just a few mm, and if that does not work, then taper the inlet some more. I have some pipes I bought that have large gaps between the end of the tenon and the end of the mortise, and I put a very small taper, or chamfer, at the end of the tenon. I do not notice that these pipes smoke particularly wet. Hopefully, this will work for you.
Thank you Marks, I'll try to add a chamfer at the end of my tenons.
Do I need epoxy to glue it ? It doesn't seem to be easy, but I've never thought about it.
Thank you again, some of my pipes will be saved !
:thumb:
You should not need epoxy for this. Go with the sand paper cone. I can't imagine you'd need to go that deep. Hopefully, this will do the trick. If not, you could always buy a premolded stem and shape it to fit your pipe. It'd be good proctice.
BTW, it is not uncommon that the button end of the stem needs a bit of work to prevent wet smoking. small needle file in the opening on the button end can increase the flow through that area and help.
So, aerodynamic is quite important : we need a tenon which doesn't resist to the air flow and this air flow has to be constant. The button must be filed too. To me, this means that we have to taper the tenon so that its very extremity has no thick.
Does anyone has ever "studied" the air flow in a pipe, as we can do around an airplane wing. It seems very interesting in order to optimize the drill for exemple. But maybe this is quite hard.
I was wondering if it's possible to "build" with epoxy, for instance, the part of the tenon which lacks, and so, eliminate the gap ?
Thanks,
Rip (who is very sorry for his poor english... )
Rip, a chamfer is a woodworking term that describes what we are talking about. No need to glue anything. By making a taper, or chamfer, on the end of the tenon on the inside, it should help with the airflow, and help reduce moisture. I would try that before adding a tenon extension, or anything like that. Sort of like below (hope it looks in the post like I typed it)
_____
____/
____
____\
Also, what Tyler suggested regarding opening the airway near the button of the stem should help as well. There should be several posts in this forum regarding airway and stem construction, etc that you could find either by looking through old posts or doing a search. These should help you greatly.
Shame on me, i made a bad translation of "putting a chamfer" in french, but this mistake gave me the idea to extend the tenon, which is not good at all.
So I have to dig a kind of V inside the tenon, as you pictured it (that's what i had in mind first). There is something I don't catch : to me the V has to go very deep inside the tenon, so that the air flow doesn't meet any resistance : the more the V is deep, the less we have resistance. Also, the very extremity of the tenon must be very thin, that is to say that the V begins at the exterior circle of the tenon. Like this, there is no discontinuity between the mortise and the hole in the tenon.
Do you agree with this ? Moreover, do you think I have to smooth the V ?
First, I would try to make the chamfer not too deep. Then I would sand it smooth. Next I would work on the button with the needle file. I'll bet that these small changes/improvements will help a lot. Smoke it for a while & see if it performs better. Half the fun of these smoking tools, to me, is the easy going attitude & slow pace they engender.
Your idea of tapering deep into the stem at a very shallow angle is right, if you want to try and reduce causes of condensation to an absolute minimum, but, as you noted, the end result will have its problems, too.
One doesn't have to go to such an extreme. Todd Johnson helped me out with just such a question in an earlier forum titled "scalloped tenon". That is a term, which comes from carpentry, that is used for what you are discussing.
Todd put a link up that shows a picture of a tenon he "scalloped". By scalloping as Todd did/does you can greatly reduce condensation without running into the problems you described. follow this link and look at the second to last pic!
The other thing you can try Rip is using a tapered drill dit to open up the airway. You could even use the chamfered tenon and tapered airway together.
If you're ineterested I put together a spreadsheet that can approximate the airflow in a pipe. It has some flaws, but all in all I was pretty pleased with it. PM me if you want a copy.
I've just finished to eat my scalloped tenon ! Very goog recipe...
I'll buy some of the tools I need today and I'll try to make those changes these days.
I've worked on one of my old pipe who smoked very wet and the result is already nice, even if my tools are really home-made !
So thank you all
I must repeat it one more time, but this forum is more then great !
You could always drill out the stem with a larger diameter bit. This solves most folks' problem with wet smokers. If you use a tapered drill bit, you'll get the gentle and deep slope you're looking for.
)
Some of my pipes have such a gap !)
