changes after completion

[Tano]

Hello Everyone,

Is there anyway I can go back to a finished pipe, and say, add a stem inlay? I'm having a hech of a time centering it on the jaws,so that I can face the shank again, in order to glue on a stem inlay.
It seem that the various steps of facing, drilling mortise and draft hole, and adding inlays, have to be followed in a certain order, but once completed there is no going back.
If I feel that an addition after completion would be an improvement, how do I do it?
Any suggestions?

Best to all,
Tano

[KurtHuhn]

A wise machinist once told me that you should center on the holes, not the outside diameter.

If you're trying to face a shank on a stummel, use a pin gauge or a drill bit that has a tight fit. Mount that in your chuck, then slide the pipe onto the drill bit or pin gauge. If it's tight enough, you won't have to do anything else. Spin slowly, and cut carefully with a cutoff tool.

A stem can be done the same way, but you can usually get by with using the drill bit you used to drill the airway.

For either operation, you're going to need to use a very steady hand if you don't have a metal lathe. It can be done, though, as I've done it many, many times.

[Tano]

Hi Kurt,

Thank you for your suggestion. That is precisely what I did before posting the question. The problem is that the tower jaws have very litle contact with the shape, not because they are too short, but rather they only grab with the outermost part of the axis. If I may exagerate a litle, think of two chopsticks holding onto a finished pipe, and no matter how slow I turn It looses the grip.

I will repeat what I think you are suggesting. Secure a tight fitting drill bit in the mortise hole, and chuck the bit in the tailstock. Bring the tailstock over to the lathe chuck, and clamp the stummel securely with the jaws, now back off the tail stock, correct?
If this is correct? The stummel shape doesn't give the jaws much to grab on to.

All the best
TANO

[KurtHuhn]

Nonononono....

Chuck the drill bit in the *headstock*. You don't need the tailstock at this point. And you should be using either a good Jacobs chuck in your headstock, or some spigot jaws on your scroll chuck. You want a decently tight fit in the mortis so that the stummel will rotate on it and not fly off while spinning.

Sounds dangerous, yes. Looks dangerous, yes. But it works really, REALLY well.

[Tano]

Thanks Kurt,
I understand now. I'll give it a try soon.

Tano

[Tano]

Kurt, one more thing ,

After glueing the stem inlay, how do you redrill the mortice and air hole? Doesn't that require chucking the stummell? Remember that this pipe was so called complete, and attempting to improve it's appearance.
I wish I knew how to repost a picture of the pipe in question, so that it would be more clear. It was the red pipe with the fancy stem, on page three of the gallery posting under Tano.

All the best,
Tano

[Butch_Y]

.

If you're trying to face a shank on a stummel, use a pin gauge or a drill bit that has a tight fit.

Basically, it's called a mandril. Pen turners use them for sure. I use Kurt's idea on almost every pipe that I can from the very beginning to turn the shank round and square it off.

If the mortise is too large for the mandril, you can use a strip of cellophane as a shim. Beware!! You do take the chance of cracking your shank, if you use too much shim.

[KurtHuhn]

After glueing the stem inlay, how do you redrill the mortice and air hole? Doesn't that require chucking the stummell? Remember that this pipe was so called complete, and attempting to improve it's appearance.

What I would do it use a piece of delrin the same size as your tenon as a guide for gluing. Put the delrin in the mortis, apply some epoxy (you won't need much here) and slide the shank end-cap onto the delrin and press it against the face of the shank. After a the epoxy has set, remove the delrin. The delrin will resist the grip of the epoxy, and should slide out easily.

I've used a similar procedure before with great success.

[RadDavis]

Hi Tano,

If the pipe is complete, I would call it done, and try my ideas on the next pipe.

Re-working a completed pipe is a recipe for disaster, IMO.

Especially if re-drilling anything at all is involved.

Rad

[mahaffy]

. . . or, if not a disaster, at least a mild nightmare of sorts. But perhaps it's something we can chalk up as "a good learning experience"; it makes you think. And sometimes use bad words.

[Tano]

Hi All

What you are saying then its like altering a suit off the rack. It will never fit the same? Time better spent on the next one? I hear ya, but you know what? Kurt has a lot of good tips, doesn't he?

Tano