invertec 275 or cst 280 for learning pipe welding

By broadhead0706 Date 10-21-2007 23:42

Hi everyone,let me start by stating this is not about bashing red or blue .Just looking for the best electric ,single phase machine, to learn to pipe weld ,and get my certification,for gas pipe welding 100 percent x ray etc. Can get a lincoln 200 d machine or 300 machine anytime from work, but to weld at home ,for 4 or 5 hrs at home in my development, people be shooting at me if you no what i mean with the noise of those babys.Here is what i need to burn 6010- 5/32 rods for root pass, and 7010- 3/16 for cap,been looking at the miller cst 280 or lincoln invert 275 ,i here you cant go wrong with either machine,but im learning, so which machine handles the 6010 rod better on root passes at single phase,lincoln claims there machine has no derating at single phase ,the miller does, but does that even matter for what im burning.Miller claims there machine you dont need to set any switch (crisp mode or hot start etc.on lincolns)because it does it automatic.One more thing, it dosent have to be either of these machine, if you feel there is a machine (electric) that can burn 6010 rod well ,but dont want to spend more then i have to ,because if i do get certified ,our truck are all big lincoln 200 or 300 machines.Any help here thank you ,and please it not about red or blue .

By DaveBoyer (*****)

Date 10-22-2007 04:58

I am probably not the best guy to give information on this as I don't weld pipe but... From the standpoint of economy I would try to find a used Lincoln Idealarc 250 or a Miller Dialarc 250. A mechanical contractor I my town had 3 of those old Idealarc 250's in the shop. I doubt any single phase transformer is going to handle the same as a Lincoln 200 or 300. I was talking to a guy near Me that has half a dozen SA 200s, He says no two of them handle the same.

By broadhead0706 Date 10-23-2007 13:37

thank you but those machines are a little big and dont really no if it will handle 6010 rods like those inverters

By DaveBoyer (*****)

Date 10-24-2007 05:08

I would like to here what some of the instructors have to say.

By aevald

Date 10-24-2007 06:47 Edited 10-24-2007 06:49

Hello Dave, I would start out by saying this: I don't believe that any of the inverters will run the rod like the SA200, 300D, or any other engine driven welder that is a generator or alternator style machine. Even the Lincoln, Miller, Hobart, General Electric, P&H, and others do not weld the same due to many subtle differences in circuitry and features. The Ranger 8's, 9's, Hobart Champion 16's, Miller Bobcat's, Thermal Arc Predator's, etc. all have differences. Inverters are in a class all by themselves and each one has features that may require a pipe welder to make some slight changes in how they weld a pipe joint. Some of the inverters in their early versions were very poor performers with E6010 and other rutile electrodes. I believe most of them have now made changes to accommodate these issues. Some of the features of the inverters will make them behave differently when a welder tries to accommodate fit-up issues on pipe grooves, when the welder goes to shorten the arc to drop the voltage to provide less heat in the puddle as a conventional engine driven welding machine would allow, the inverter might instead increase the usable heat to keep the arc from extinguishing. On the opposite end, when the traditional engine driven welding machine is being used and the operator goes to pull a long arc to increase the heat to open up a tight groove the same action on an inverter might give different results.
My suggestion is pretty simple, he should use the machine at work that will likely be the one that would be used when he is actually going to weld pipe, get a feeling for how it runs the two types of rod that will be used. Then make arrangements to weld with the various inverters that are available from welding suppliers in the area to make a comparison as to which one(s) weld in a similar fashion. They should be able to set something up for him to "test drive" these machines. Once he's done this it would probably be a matter of deciding on the price and any other relevant issues. My $.02. Best regards, aevald

By swsweld (****)

Date 10-25-2007 00:35

broadhead0706, I will try to get get back w/you tomorrow with the CST280. Just got one recently and will test it out Thursday with 1/8 6010. Our WPS is uphill you probably will be vert dh for gas line. We are using a Miller Dialars as Dave suggested and it does a great job. It is bigger though.

By broadhead0706 Date 10-25-2007 15:06

thank you all. i would love to use those 200 or 300 machines BUT not allowed in this development.I would believe all machine might feel or weld a little different,my friend who is welding now for 27 years welded a 12 inch joint, ( root pass 5/32 -6010 rod with he said would pass any x ray.)with and inverter 250 from lincoln.with no problem.again 27 years is a long time .And again , i seen some welding school,on line, for teaching pipe welding they had about 80 cst 280 miller machines.

By swsweld (****)

Date 10-26-2007 01:08

Made a few welds w/cst280 today and it did fine on 6010 and 7018. Wasn't the best machine I ever used but more than adequate to get dialed in for the certification test. I think it was $1100.00 -$1200.00 new.
AS Allan said the older inverters were not great for 6010. I had a Thermal Arc 300 GST that was great for everything except 6010. The arc control on the 280 did not change the arc drastically. Also I was using 1/8" rods uphill. Hope the training and test go well for you.

By broadhead0706 Date 10-26-2007 20:26

thank you , and yes it is down hand, and in n.y.c.,n.j. that cst280 is 1800.00the cheapest ive seen or on line