FS: Wife, two cats... Erm...

Damn, I was just about to mention the brass matchbox holder I made at
school - I'm sure I was onto a winner with that one.

 

Well post a link to a photo and we'll have a vote on it.

 

Yeah. Whereas Mr gobshite super-machinist is talking about a mobile boring
jig he fastens onto a stern tube and skims little cuts out, I'm talking
about bloody great pump casings weighing several tonnes spinning round at
120 rpm while I rip 12mm depths of cut off at Metal Removal Rates which
would make his eyes water.

 

I love it when stuff like this happens.

 

You lead such a dull life

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, tallbloke

Which relates to the point you were trying to make about the small lathe
on the trailer being useless how, exactly?

Just out of interest, like.

--
Wicked Uncle Nigel - Manufacturer of the "Champion-105" range of rearsets
and Ducati Race Engineer.

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
SBS#39 Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
Suzuki TS250 "The Africa Single" Yamaha GTS1000

 

Pink, you mean? Sort of 'Gay Machinists do Africa'?

 

tallbloke says...

You obviously haven't seen the work they did where Andy served his time.
Clue: they built cruise ship engines for Rolls Royce.

 

Depends what tool he's using to rip, doesn't it?

 

Whoopsydoo, The firm I served my time at build bigger ships engines than
Rolls Royce ever have.[1] They also build the particle accelerator
chambers at CERN and the biggest nuclear boiler feed pumps in the world.

It makes me laugh when Bonners spouts about heavy chain blocks and then
says he's not getting into a pissing competition. Still, he had my respect
as an engineer until he became so condescending towards others.

[1]here's one of the smaller ones ;-)
http://www.shipsnostalgia.com/gallery/data/500/336sulzer_engine_port.jpg

 

That's the original BMW K100 engine, before they realised the scale on
the drawing was in millimetres and not feet.

 

As I said earlier, it's a matter of the ratio of the weight of the
component to the machine and it's damping. Obviously, the balance is a big
factor too. In the case of large pump casings there are large out of
balance forces, and the key to preventing vibration striations on the
machined surface lies in the correct pressure being applied between the
tool and the job. That the fucking great machine it's spinning round on
will be properly shimmed and bolted down goes without saying. This is
where finding the right tradeoffs in tool life, MRR and surface speed sort
the properly qualified machinist from the hobbyist. No offence intended to
you Nigel, but when you are making items at home, you aren't under the
same time=money and tool insert life constraints that you deal with in a
production environment.

A lathe mounted in a trailer will be fine for smallish components made
from bar stock and tube, but you may well get 'ringing' problems if you
try to skim brake discs for example, or small cuts along long shafts made
from harder materials. It all depends what resonant frequencies get set up
when machining, and in general, the heavier, and more solid, and better
damped the machine is, the less vibration problems you'll suffer, given
that the bearings in the machine and the cross slide shimming etc is all
good.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, tallbloke

Of course not. The speeds and feeds I use bear absolutely no resemblance
to those used in a commercial shop. I optimise mine for tool life and
reduction of strain on my ageing, unbolted-down machines.

Not if you spend the time to **** about to find the speeds where you
don't. Or set up a travelling steady. And that's what home shop
machinists do.

Agreed. So we now agree that the trailer mounted tools are in fact
useful, and we both want them. Right?

--
Wicked Uncle Nigel - Manufacturer of the "Champion-105" range of rearsets
and Ducati Race Engineer.

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
SBS#39 Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
Suzuki TS250 "The Africa Single" Yamaha GTS1000

 

Just to revisit this in the light of your subsequent comments.

How can they be fastened down with enourmous chain blocks if they aren't
secured to anything?

You seem to have undermined your contentions about your machines being
fastened to thin air and submarines hovering gently in the aether just
above their dry-dock moorings.

You were just being an argumentative twat for nothing as usual weren't
you? ;-)

 

ROFLMAO

Good old BMW, easy access as ever, although they seem to have ditched
the ladders on my K75.

 

To an extent yes. Factory shop machinists use travelling steadies and have
to **** about with speeds and feeds too you know. I'm just pointing out
that the better the machine is fastened to the rest of the world, the less
vibration problems you'll suffer.

Ok have it your way. bid on it. Make sure it ain't too wide for british
roads first though ;-)

You can always reduce the tyre pressures on the trailer to change the
vibration frequencies, but if you're machining on the move, make sure it
doesn't cause unusual wear patterns on your tyres.

 

So says you. I reckon you're the Walter Mitty of 'O' Level metalwork.

 

Heh, you're showing yourself up as more and more of a clueless ****
every time you post.

Do a search for NEI or APE Allen, you'll see the type of equipment I
worked on in both the heavy machine shops and the fitting shops.

I'm a long way from being a 'super-machinist' but I try to avoid
making sweeping statements that are so far away from being correct
it's almost painful. You managed to do that and then when challenged
on it you made another very brave statement about safety regs which I
notice you haven't been able to back up yet. Any proof will do, as
long as it's a regulation and as such legally binding.

 

snip>

The point I was trying to make about chain blocks is that 3 tonnes is
very small. You prattle on about 3 tonne castings as if they're big
lumps of kit but they're not. You also posted that equipment had to be
secured firmly when it doesn't. I've no doubt it'll be a long wait for
the proof about safety regs stating that machines have to be secured
onto concrete bases but that's not going to be such a shock.

Btw, posting links to marine engines is great but did you work where
the engine was manufactured and if so did you work on similar sized
engines? I might be way out here (if so I'll apologise now) but at a
guess you might have worked at Sulzer pumps in Leeds and I didn't
think they made marine units there.