Learning to lathe [things]

[Anglepoise]

yclo.

Looks great.
Having the two knurls not exactly in line is a function of the holder and you might be able to tune things a bit with washer/spacer or a bit of machining.

The reason that you could not move the saddle was the fact that you had the full pressure on the knurls.

What you did was correct. Turned by hand and got both knurls tracking.

Once they are tracking correctly then you can back off the pressure and then traverse the saddle to lengthen the knurl. You have to loosen things a bit as the
knurls are embedded and to move them requires allot of horse power.

[PhotonFanatic]

Another day with the lathe. Another day wasted.

Today I wanted to try for a couple of things: 1) Do my first internal threading; 2) Use my new Tripan boring tool holder that works with collets; 3) Use my four-jaw adjustable chuck and adjust it properly; and 4) Practice my drilling and boring.

The goal was to fit a Kroll switch into the end of battery tube, so that the Kroll would be flush with the outer surface when screwed in place.

First I set-up the four-jaw with the round bar, roughly 22 mm in diameter to start with. It had been used before for threading practice, so it did have a smooth section near the jaws of the chuck that I could use for indicating.

One the chuck was adjusted and everything was fine, then I brought the stock down to 18.60mm and faced the end.

Next up, drill a hole deep enough to clear the Kroll Switch, including the spring. Then I tried boring that out to my minor diameter for the 5/8-28 threads. Unfortunately, I overdid it just a tad, not enough to ruin the job, but not spec on, either.

Then I bored out a 1.75mm deep recess to accommodate the rubber boot that forms a fairly waterproof seal, if it is seated properly inside the battery tube.

Finally, a chance to use my new tool, a Tripan boring/threading bar holder that has a 27mm bore in it, into which is inserted a stainless steel sleeve that is designed to accept the W20 collets that Schaublin and my Wahli use. This is really sweet because the collet set that I have ranges from .5mm to 20mm, in half-millimeter increments. That means that regardless of the shank size of the boring tool, or threading tool, I will most likely have a collet to fit it.

Dug out the threading bar that I planned to use, put it in the right collet and tightened down everything before starting the threads.

Thanks to Anglepoise's tip on covering the area to be threaded with black ink, it was fairly easy to do the internal threading. And, of course, a Groovy provided the light to peer into the end of the battery tube.

Once the threading was done, decided to throw a few grooves into the battery tube to break up the visual monotony.

Here's what the piece looked like before inserting the Kroll switch:


And with the switch inserted:


What I didn't do that I need to work on: Bevel the area where the threads start and place a slight bevel on the bore where the rubber boot contacts the battery tube.

Sadly, all this work doesn't even come close to resulting in a usable piece. Unless someone wants a Desktop Phallic Paperweight.

[PhotonFanatic]

.

[yclo]

Thanks Anglepoise, will try that when I attempt my next knurl.

PhotonFanatic - engrave something on the bottom and you have a nice stamp!

I read somewhere that you shouldn't apply too much pressure on a thin walled part, now I know why...



-YC

[EricMack]

Another day with the lathe. Another day wasted.

Sadly, all this work doesn't even come close to resulting in a usable piece. Unless someone wants a Desktop Phallic Paperweight.

Fred - I don't think that's wasted time at all, just the dang learning curve!

Looks great man, but hmmmm, not quite sure that shape grabs me. Guess its OK if you like it...





Looks good man!

[TranquillityBase]

Show us the Tripan boring/threading bar holder...Please...

TB

[PhotonFanatic]

Fred - I don't think that's wasted time at all, just the dang learning curve!

Looks great man, but hmmmm, not quite sure that shape grabs me. Guess its OK if you like it...


Looks good man!

But, but -- it's ribbed! That should make it more valuable in the eyes of some, no?

[PhotonFanatic]

TB,

As you requested.

First photo shows the holder on the compound slide. In the lower left is the stainless steel sleeve with the locator pin showing. Behind that is the locking nut that will pull the collet into the toolholder and tighten the collet around the bar. The collet is to the right of the sleeve, obviously.




Next we have the pieces in place, but before the collet is closed:


And now, it is ready to go:


As I mentioned before, with a wide range of sizes available for selection from the collet set (came with the machine), I can handle boring bars with varying shank diameters:



OK, last boring picture (pun intended):

[wquiles]

Awesome! Thanks for the pictures

Will

[will]

What I didn't do that I need to work on: Bevel the area where the threads start and place a slight bevel on the bore where the rubber boot contacts the battery tube.

I use the same threading tool to put the bevel on the front and back of the thread. I generally put a relief, a cut a few thousanths deeper than the bottom of the thread. This eliminates the burr you sometimes get. It also makes it easier to screw the parts together.

[PhotonFanatic]

will,

Sometimes the simplest solution can be the hardest to find.

That's a great idea, I have no idea why I couldn't figure that out myself.

[Anglepoise]

Thanks Anglepoise, will try that when I attempt my next knurl.

PhotonFanatic - engrave something on the bottom and you have a nice stamp!

I read somewhere that you shouldn't apply too much pressure on a thin walled part, now I know why...



-YC

We have all done it. Lots of time spend boring out , only to have it all collapse.
Get all the knurling done before boring. Also any deep grooving or anything that might catch an edge. You would be amazed how lightly it is possible to grip a thin wall part, as long as the cut is oh so very light and keep the speed up.

[Anglepoise]

Fred,
Looks like things are progressing very well.
Enjoy,

[TranquillityBase]

That's what I'm talking about...AWESOME!!!

I gotta make one of those, I think it can be accomplished with a 5C collet block set...

Nice lay-down threading tool holder...looks to be a carbide shank.

TB

[PhotonFanatic]

That's what I'm talking about...AWESOME!!!

I gotta make one of those, I think it can be accomplished with a 5C collet block set...

Nice lay-down threading tool holder...looks to be a carbide shank.

TB

A lesson to the wise: Never order a part without knowing the price beforehand.

Yes, it is a beautiful solid carbide bar--and it only cost me $250!

Of course it is as solid as a rock, so I can't complain, just whimper about the price.

[TranquillityBase]

You won't regret it...

TB

[will]

A lesson to the wise: Never order a part without knowing the price beforehand.

Yes, it is a beautiful solid carbide bar--and it only cost me $250!

Of course it is as solid as a rock, so I can't complain, just whimper about the price.

just don't drop it ...

[Anglepoise]

Very nice to be able to revolve the tooling within the collect to adjust rake.

[PhotonFanatic]

Another day, another chance to play with the lathe.

I had agreed to thread some cut-down Mag D tubes for cy, but of course I had no clue how difficult it could be to work with tubes of such large diameter, well they are large compared to what I had been working on, i.e., 1" or less diameter.

Well, while doing the job, I screwed up one of the cut-down pieces, so just for fun I wanted to see how easy it might be to bore out the Mag D. Here is the original wall thickness:





Then I just took a bunch off until it looked as thin as I'd want it to go (without regard to threading, mind you):




OK, what did I learn today? That these cut-down tubes are easier to work with if you use internal chucking instead of trying to hold them on their exteriors:


Still a pain to work with, especially if you are trying to thread the tailcap threads, i.e., you can't use a center to support the piece. Still, the results are tolerable:

[Mirage_Man]

OK, what did I learn today? That these cut-down tubes are easier to work with if you use internal chucking instead of trying to hold them on their exteriors:


Still a pain to work with, especially if you are trying to thread the tailcap threads, i.e., you can't use a center to support the piece. Still, the results are tolerable:

It's even easier if you make a set of soft jaws that allow you to hold on the outside and have the end just out side the jaws. Like this...



Oh and don't forget the little bevel right on the inside edge of the tail cap end. It helps guide the O-ring in.

Same thread job as above hit with a gray Scotch Brite for a few seconds.



MM

[PhotonFanatic]

It's even easier if you make a set of soft jaws that allow you to hold on the outside and have the end just out side the jaws. Like this...



. . .

MM

Brian,

That's fine, if you have a big lathe and a big chuck, both with bores large enough to accommodate the diameter of the Mag. Unfortunately, the bore on my lathe is 20mm max.

Good reminder on the bevel for the O-ring, thanks.

[TranquillityBase]

Fred, I know you're having fun, and I also know how exciting it is to try new methods and different new tooling etc., but that method of chucking a long part is very dangerous...If you need to chuck a long part using that same method, because the I.D. size limit of you chuck, use a steady rest to support the end you're working on.

Even at a low spindle speed, if that part lets loose...look out!

This is 'been there, done that' talking...Two four foot fluorescent tubes smashed just above my head, from a wild part...Safety glasses are only marginal protection from hundreds of thin, and tiny shards of flying glass. And it all happens in a split second.

Scott

[will]

Fred, I know you're having fun, and I also know how exciting it is to try new methods and different new tooling etc., but that method of chucking a long part is very dangerous...If you need to chuck a long part using that same method, because the I.D. size limit of you chuck, use a steady rest to support the end you're working on.

Even at a low spindle speed, if that part lets loose...look out!

This is 'been there, done that' talking...Two four foot fluorescent tubes smashed just above my head, from a wild part...Safety glasses are only marginal protection from hundreds of thin, and tiny shards of flying glass. And it all happens in a split second.

Scott

I have to second this. when something comes off the lathe - it tends to snap very quickly, no time to react and get out of the way. I do my work standing to the side, not directly in line with the work being cut. I worked as a machinist for a few years, (I still have all my fingers)

I have a mini-lathe here at home. I was able to bore out the chuck about 1/8 inch so I could fit the barrel of a mini-mag inside. You might be able to the same. I only bored out the chuck, not the tube that goes through the headstock. This worked very nicely for me, it might not on the lathe you have.

[PhotonFanatic]

I'd like to thank TB and will for pointing out how dangerous a lathe can be, especially when you are learning on your own, or through books only.

Needless to say, I have had mishaps, almost all of them resulting from either misusing a tool, or taking too deep a cut on an unstable piece.

I do try to be real careful, double or triple checking the chucking tightness, runout, clearance, etc., etc., and most importantly, I try to keep my hands away from any spinning part.

So far, so good.

OK and now today's lesson.

Wanted to try an idea that I had for a head which would involve cutting on an angle and then feeding a tool into the tapered part to create a pattern. Worked pretty good until it came time to part it off, when I decided to try a new parting tool. Mistake! I should have practiced with the new tool on just a plain bar first, not on my almost complete part. Another day, another lesson learned. :-(

Still I managed to salvage enough to say that I do want to try this as a production idea:



And from a different angle:


Sorry about the focus! And finally, my last chance to bore you to tears.


In case you were wondering, no, the head was not designed for a CR2 light, something much bigger really. I just used the CR2 battery since the proto fit so well on it.

[Anglepoise]

I have been caught out a number of times in turning an external groove, only to 'part' the item. This can be a very time consuming error if one has done extensive machining on the part all ready.

Lately I have been designing my parts on paper first and my 'error rate' has dropped right down.
Also its nice to have a record of parts, particularly flashlight bits that one might need to duplicate at a later date,

Solid Works (Edit: sorry Solid Edge ) is now a free download and I found it relatively easy to learn.

[PEU]

Solid Works is now a free download

??????


Pablo

[Morelite]

??????


Pablo

I think he means that Solid Edge 2D is a free download.

[PhotonFanatic]

I think he means that Solid Edge 2D is a free download.

Right, and it is only 239MB! Be prepared to have that take a while.

[wquiles]

Right, and it is only 239MB! Be prepared to have that take a while.

That depends. I have Verizon FIOS at 15Mbit/s for downloads - it took about 2 minutes and 5 seconds for the complete download

BROADBAND RULES

Will

[kenster]

Fred, your "Learning to Lathe" thread has been killing me to follow along in the shadows and read! So ........ not as sweet as I wanted to get but..........


Kenster has a Lathe on it`s way!


My questions will be dumb of course, but I hope I can get guidance while learning from you and these other "Masters"

Ken