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Colin KC
21-01-06, 05:39 PM
Anyone know about these things? Daaaannnnn;)

is this one on ebay any good?

item # 7583654480


Cheers

owen bush
21-01-06, 06:05 PM
murex are a verry good make .I have two of their welders and they are exelent and v robust. However plasma cutters are renound for dying and prone to verry expensive problems and can be ruined if not looked after by previous owners ie by not putting propper moisture traps in. I would want to try one before i buy .In general single phaze ones that Ive used have been verry wussy and will only cut 3mm clean and up to 6 mm verry rough and slow .what do you want to use one for?

owen bush
21-01-06, 06:19 PM
murex are a verry good make .I have two of their welders and they are exelent and v robust. However plasma cutters are renound for dying and prone to verry expensive problems and can be ruined if not looked after by previous owners ie by not putting propper moisture traps in. I would want to try one before i buy .In general single phaze ones that Ive used have been verry wussy and will only cut 3mm clean and up to 6 mm verry rough and slow .what do you want to use one for?

mikesknives
21-01-06, 06:21 PM
i've just bought a new one can't remember what make it is at mo Butters i think single phase cuts 12mm clean 15 mm severance new invertor technology i think its very good.

mike

owen bush
21-01-06, 06:39 PM
Ah the wonder of technology that sounds good .I think inverters have now grown up in to amazing things . A 12mm cut is verry handy .I wonder what the murex'll cut spec probably on side.

Colin KC
21-01-06, 06:59 PM
Thanks guys, it says 5mm on that one, looks like I'll have to go for a new(er/ish) one with inverter then:)

ZDP-189
21-01-06, 07:22 PM
Stop! Wait....

Before you buy, bear in mind that it is night impossible to get a good clean cut in 3-4mm steel and you'll more than likely cack the cut billet up with globs of molten steel, clean up time normally exceeds cutting time by several times. It is very difficult to see the scribe line with a plasma stream on too.

An angle grinder works much better.

A plasma cutter is called for if the plate is thin, say under 1mm (less globs of steel), where there are many inside curves that would be difficult to cut with a disc, where the steel is a particularly tough alloy, e.g. T16 HSS, or when you are doing fabrication with lots of rapid cutting, such as rough cutting angle iron or strap.

Colin KC
21-01-06, 08:18 PM
Aaaah, cheers Dan, so it's not at all a clean cut then?

narsil
21-01-06, 08:27 PM
For up to at least 2mm steel sheet (depending, I suppose on the specs of the machine) You can get a very clean cut as long as you move the torch at the right speed. BLobbyness comes from a) cutting too slowly b) the torch not being in contact with the metal. I know this because I haev been deliberatley creating blobbyness.

Ive got some plasma cut sheet ( about 1mm, 20 swg I think) right in front of me right now as it happnens, I try and scan it later so you can see. Going by the oxide colours the heat affected zone is about 1mm either side. The cut is very clean indeed, if you move the torch fairly quickly.

If it would be any help I'll take some O1 into college onmonday and try it out with the machine there.

imagedude
21-01-06, 09:42 PM
If you only intend cutting ferous metals I'd use oxy-gas. Storing the bottles in a domestic garage may be a deal killer though. Would a metal cutting bandsaw be a better bet?

Wayne D
21-01-06, 09:50 PM
If it would be any help I'll take some O1 into college onmonday and try it out with the machine there.


already done that at Uni mate, it's how I cut my 4 and 5mm O1 bars for my heavy knives !

you get a 'burn area' of about 3mm diameterand then a heated area of a further 4 - 6 mm diameter; I cut it about 4mm away from my scribe line and then grind it back the 1 or 2 mm to my pattern marks.

it's quite easy to screw up the steel and your pattern without practice, my first 3 or 4 attempts at 7" bowie patterns became 3" or 4" small blades because i totaly buggered up the O1 :rolleyes:

mikesknives
21-01-06, 10:52 PM
the shape of my torch allows me to run it on a template no scribe to follow just the speed to worry about. a clean cut comes from changing your consumables regularly.

best bet is take your material of choice to your nearest dealer and ask for a demo, any dealer worth dealing with will be fine with that i'm sure.

mike