pipemakersforum.com

Hey guys, I did a brief search on this and didn't find any concise answer. I've made my first few pipes with delrin tenons, but I've noticed that you pros seem to prefer integral tenons. From my background delrin would seem to be superior... It's stronger than acrylic, has a natural lubricity, and is somewhat elastic. It also tends to straiten itself over time, so improper storage of the pipe would not effect the stem fit. (Providing the tenon was made strait in the first place.)

But this knowledge is from a non-pipemaking background... so what's the deal?

Oh, ye have stumbled into troubled waters....

andrew

Delrin tenons are more accessible to beginners, which has had the effect of stigmatizing them to some degree. As in a, "Real pipe makers don't need a crutch!" sort of way.

It's nonsense, of course---a PROPERLY installed Delrin tenon is just as good as an integral one---but there's no arguing with Humans Who Believe Things, regardless of subject.

They are also "newfangled" in a tradition-conscious, codger-heavy hobby.

In another 5-10 years, no one will remember what all the fuss was about.

There's no right answer.

You can't make a beautiful clear/amber acrylic stem with a block of delrin glued in, it shows.

But yes, on all grounds of function over form, delrin or teflon is better, particularly better than snappy old acrylic.

On rubber stem material I'm fine with integral.

No one cares in the real world as long as it's not ugly.

IF you have a lathe it is actually easier and less work to cut a tennon, I have never used a tenon cutting tool so I can't say for that, also when using delrin you have to allow for a certain amount of ebonite or acrylic to accept the end of the delrin you glue in, so if you wanted to make a shallow type of saddle you would have less stem to drill and mount your delrin into, also the diameter of the stem you make at the shank junction would be determined by the size of the delrin so you don't accidently sand into it, use what ever you like, and you'll make a decision all of your own after you do enough of them

Short answer: yes, delrin is fantastic in many ways... however...
*inhale for wind-bag-ish answer*
Delrin doesn't polish, the tenon/mortise joint introduces an additional failure point, it's ugly, ugly, ugly, you have to wait a whole 5 minutes for epoxy to dry, it's an extra design constraint, and depending on who you ask an integral tenon is an additional mark of craftsmanship.
Lots of carvers use delrin, sometimes there is no choice but to use it. Generally integral tenons are confined to ebonite.
Just about anything else (except a couple acrylics) will use a delrin tenon.

andrew

Both are reasonable solutions. Delrin will force your saddles to be further away from the shank than an integral tenon would. Also, stems are more easily replaceable than shanks. Delrin is strong enough that the shank will sooner break than the tenon. It does, however take a nice polish and lets you make a mortise without a chamfer.

I typically turn tenons because that lets me keep working instead of waiting for the epoxy to dry. Both are good solutions. Just be sure that the fit is right and won't come out. I don't think it's a big deal either way. Some collectors have preferences for one or the other.

andrew wrote:Delrin doesn't polish, the tenon/mortise joint introduces an additional failure point, it's ugly, ugly, ugly, you have to wait a whole 5 minutes for epoxy to dry

Depending upon your epoxy, you can wait up to an hour. I have been. =/

Delrin is great because:
1. You're guaranteed the same fit every time.
2. Replacing a delrin tenon is fairly easy.
3. Arguably less easily damaged.
4. It's cheap as dirt

Delrin sucks because:
1. Epoxy.
2. It restricts the design of your stems.
3. Visual issues with acrylic.
4. Did I mention epoxy?

Integral tenons are great because:
1. Unrestricted stem design potential.
2. No visual issues when using acrylic.
3. Quickly made with practice.

Integral tenons suck because:
1. For a while, your fit will not be the same every time. (I'm guessing due to the learning curve).
2. They're harder to repair if they break.
3. Arguably easier to damage.
4. You consume extra, more expensive materials.

I think that's a fair comparison of the pros and cons. If I missed anything, please chime in.

George, I'd be interested to hear about your experience with the longevity of delrin and integral tenons, specifically the types of damage that can and do occur.

d.huber wrote:

andrew wrote:Delrin doesn't polish, the tenon/mortise joint introduces an additional failure point, it's ugly, ugly, ugly, you have to wait a whole 5 minutes for epoxy to dry

Depending upon your epoxy, you can wait up to an hour. I have been. =/

Delrin is great because:
1. You're guaranteed the same fit every time.
2. Replacing a delrin tenon is fairly easy.
3. Arguably less easily damaged.
4. It's cheap as dirt

Delrin sucks because:
1. Epoxy.
2. It restricts the design of your stems.
3. Visual issues with acrylic.
4. Did I mention epoxy?

Integral tenons are great because:
1. Unrestricted stem design potential.
2. No visual issues when using acrylic.
3. Quickly made with practice.

Integral tenons suck because:
1. For a while, your fit will not be the same every time. (I'm guessing due to the learning curve).
2. They're harder to repair if they break.
3. Arguably easier to damage.
4. You consume extra, more expensive materials.

I think that's a fair comparison of the pros and cons. If I missed anything, please chime in.

George, I'd be interested to hear about your experience with the longevity of delrin and integral tenons, specifically the types of damage that can and do occur.

That's a good list.

One thing that should be added is that since Delrin is so slippery tenons made from it must be slightly larger in diameter for the same mortise to get a secure fit. I've seen this cause problems with thin-walled shanks. Some pencil shanks, but mostly those where the wall thickness varies dramatically like squares and thinly flattened ovals. The additional outward pressure caused by the larger diameter tenon will cause them to spontaneously crack after a while at the thinnest point. (Meaning not just from dropping. Heat and humidity cycling is apparently enough to do it.)

The solution would seem to be a pre-emptive decorative band, of course, but square ones are a pig bitch to fit, and oval ones aren't particularly attractive. Also, by then you've more than given back the labor and materials cost advantage of using Delrin for the tenon.

andrew wrote:Delrin doesn't polish, the tenon/mortise joint introduces an additional failure point, it's ugly, ugly, ugly, you have to wait a whole 5 minutes for epoxy to dry

Delrin does polish very easily. I do it on almost all of the pipes I make. It is very possible to make the joint look good, and if done with a very good mechanical fit there will never be a failure. I usually take a 5+ minute break after each of the 100+ steps to make a pipe so the wait is no issue for me. I think that is why it takes me so long to make a pipe

d.huber wrote:
Depending upon your epoxy, you can wait up to an hour. I have been. =/

Delrin is great because:
1. You're guaranteed the same fit every time.
2. Replacing a delrin tenon is fairly easy.
3. Arguably less easily damaged.
4. It's cheap as dirt

Delrin sucks because:
1. Epoxy.
2. It restricts the design of your stems.
3. Visual issues with acrylic.
4. Did I mention epoxy?

Integral tenons are great because:
1. Unrestricted stem design potential.
2. No visual issues when using acrylic.
3. Quickly made with practice.

Integral tenons suck because:
1. For a while, your fit will not be the same every time. (I'm guessing due to the learning curve).
2. They're harder to repair if they break.
3. Arguably easier to damage.
4. You consume extra, more expensive materials.

I think that's a fair comparison of the pros and cons. If I missed anything, please chime in.

George, I'd be interested to hear about your experience with the longevity of delrin and integral tenons, specifically the types of damage that can and do occur.

Integral tenons suck because:
1. For a while, your fit will not be the same every time. (I'm guessing due to the learning curve).
Integral tenons can be stabilized very well so there is much less of a chance for the sizing to change. The mortise also must be stabilized. Learning curves in turning tenons usually lies with experience using a metal lathe or turning by hand tool on wood lathe, and stabilization for both tenon and mortise.

2. They're harder to repair if they break.
Yes, but better the tenon breaks than the shank.

3. Arguably easier to damage.
See above

4. You consume extra, more expensive materials.
Material cost of 3/4" of vulcanite or acrylic is not much.

Delrin sucks because:
1. Epoxy.
Epoxy ain't so bad. Just don't get it on your d#*k.

2. It restricts the design of your stems.
There is no restriction in design if you make a very good mechanical fit, but yes, it is much easier to do an integral when the going gets tough on the design.

3. Visual issues with acrylic.
The visual issues can be remedied with different colored delrin or application.

4. Did I mention epoxy?
Yes

There is almost always a solution with either integral or delrin, and they each have their uses. Be able to do both and you will not have any restrictions.

PremalChheda wrote: Delrin sucks because:
1. Epoxy.
Epoxy ain't so bad. Just don't get it on your d#*k.

This was sooo funny I spit my coffee! IAWP

Ocelot55 wrote:

PremalChheda wrote: Delrin sucks because:
1. Epoxy.
Epoxy ain't so bad. Just don't get it on your d#*k.

This was sooo funny I spit my coffee! IAWP

Premal, do you have A story you would like to share with the class?

Premal does have a good point in that it is good to be able to do both.

And although I have no personal experience with getting epoxy anywhere near my nethers, my finely honed intuition and Premal's wisdom both tell me that situation would have dire consequences....

andrew

Ocelot55 wrote:

PremalChheda wrote: Delrin sucks because:
1. Epoxy.
Epoxy ain't so bad. Just don't get it on your d#*k.

This was sooo funny I spit my coffee! IAWP

I read the label carefully, and couldn't find a single reference against this application.
It keeps stiff a long time and its a lot cheaper than Viagra. Whats the problem ??

Alden wrote:

Ocelot55 wrote:

PremalChheda wrote: Delrin sucks because:
1. Epoxy.
Epoxy ain't so bad. Just don't get it on your d#*k.

This was sooo funny I spit my coffee! IAWP

I read the label carefully, and couldn't find a single reference against this application.
It keeps stiff a long time and its a lot cheaper than Viagra. Whats the problem ??

'Not a male form of birth control'.