Machined pengun - Dimply

[jackssmirkingrevenge]

Aaargh, missed it!

And yes, it's a pretty big pen gun. The whole "serviceable" thing needs space y'know

[LeMaudit]

I never realized how big the pengun

It's because if it doesn't work, I'll stick some fins and send it to MrCrowley to fire the bitch on a beach.

Uploading again, should be completed in an hour or so

[Gun Freak]

Why does the brass lose the yellow color when you machine it?

[LeMaudit]

It's called oxidation I think
Brass tarnish to a dark golden color, but fresh cut it is light gold.

[jackssmirkingrevenge]

It's because if it doesn't work, I'll stick some fins and send it to MrCrowley to fire the [female doggy] on a beach.

A spudgun within a spudgun?

Why does the brass lose the yellow color when you machine it?

That's its natural colour, the yellow is the patina which builts up due to the air.

[LeMaudit]

A spudgun within a spudgun?

I'm working on a Matryoshka/Katyusha Rocket design

[LeMaudit]

Here we go again!
Step 7. The last external piece. Now I'll work on the internals

[youtube][/youtube]

[jackssmirkingrevenge]

*fa...er... can't wait to get home from work and burn through some brass!

[LeMaudit]

JSR, just to ease your pain about redoing work...

me too I had to redo this piece... look, there was a beump on the edge.

I first wanted to hold the piece only by the little rod onto the chuck... it was not long enough and the piece get loose and was stuck between the tool and the chuck.

Please also note that the fact that this mistake was not preventing the piece to work nor was visible inside the aluminum cap is completely irrelevant

[jackssmirkingrevenge]

me too I had to redo this piece... look, there was a beump on the edge.

I can just picture that

"Sacrebleu, une beump!"

*bins*

Please also note that the fact that this mistake was not preventing the piece to work nor was visible inside the aluminum cap is completely irrelevant

That clarification was far from necessary

Anyway, redid the nose part, this time I made the thread first, now much more crisp, and made everything else around it. Still not perfectly concentric but better than my previous effort, and the correct length too

[LeMaudit]

"Sacrebleu, une beump!"

Sacrebleu cannot come close... in fact if I remember well what I said was in Spanish and involving one's mother.
I'll never do direct TV show

Good job on the redoing!

Just to be sure, when you say it is not concentric, is it when you screw it in the brass piece? Or looking at the bottom? Because it is normal the bottom is off center, due to the thread. Also, hand made threads are never perfectly concentric, this is why my body's step turn everything down to the final diameter; nose, plug and body. That way the concentric errors are canceled

[jackssmirkingrevenge]

Sacrebleu cannot come close... in fact if I remember well what I said was in Spanish and involving one's mother

The thought of Jacques Clouseau uttering "Me cago en su puta madre!" is as amusing as it is disturbing

Good job on the redoing!

Thanks but still not happy with it. Do Sherline pump gaseous perfectionism into their packages before sealing them?

Just to be sure, when you say it is not concentric, is it when you screw it in the brass piece? Or looking at the bottom? Because it is normal the bottom is off center, due to the thread.

Screwed in the brass piece, the centre hole wasn't concentric. I tried to avoid it with the following cutting plan but it doesn't seem to have worked :-/ As far as I can tell the theory is sound, cut the thread, use it as the new centre reference in the brass part and turn down everything around it - I think I'm cutting the ali too deep/fast and it's knocking it off centre in the chuck.

[Fnord]

I think someone's social life may be afflicted by a version of "elder scrolls 4" syndrome over the next few months...

[Zeus]

Fnord, that's not fair, I'm sure JSR will clean up the swarf.

Also, thanks to LeMaudit, I've not seen live machining before. But isn't the leadscrew a bit awkward to use being out so far?

(I presume it's the leadscrew, the thinggamybobby that feeds the tool towards the headstock)

[jackssmirkingrevenge]

I think someone's social life may be afflicted by a version of "elder scrolls 4" syndrome over the next few months...

HAHAHA! Excellent! Isn't the the "someone is wrong on the internet" one

I actually had this conversation with LeMaudit, last night I had been planning on having a go at machining the pen gun body but my friends were having a drink nearby and I forced myself to join them, otherwise I am on the road to becoming the guy who sits on a bench shouting at passing busses before the age of 65

Fnord, that's not fair, I'm sure JSR will clean up the swarf.

No, that's pretty much what it looks like - I brush of the lathe frequently but not the floor - and the swivel chair and table is quite accurate too

isn't the leadscrew a bit awkward to use being out so far?

Not really, I've found it quite comfortable to work with so far. The only problem is that I sometimes reach for the tailstock handwheel instead

update: was going to start the body but since it is so dependent on the endcaps which I'm not too happy with, so I'm remaking those first.

Here's the endcap first stage, cutting the thread. Note that it's much better cut that the previous one, and that I added a 5mm extension (which will later be cut off) turned down to the thread minor diameter to help keep things centred and make the die bite more easily. Note also the marks where it was held in the vice and how tightly it was held in order to cut the thread without slipping.