7018 rods will not strike an arc

[Jim mcgrath]

I purchased 7018 rods from Amazon but they are difficult to strike and cut out after a few seconds. I managed to run one short bead which looks bad (see photo). The welding machine is an old Clarke 180 air cooled machine. The rods are 3.2mm. The bead with the arrow pointing to it is the 7018 one. This was the only weld I was able to do with it, the other types of rods I use weld ok.
Does anyone know what might be wrong? Thanks.

 

[zzr1200]

If it's a buzz box you need 6013 rods not 7018.

A buzz box doesn't have the OCV required....Sorry

 

[Erie Fred]

Are you attempting to run these on A.C. ?
Also, when restarting usually you break off the flux that hardens
on the ends.

 

[BrokenBiker]

probably havent got a high enough OCV for 7018

 

[premmington]

Buzz box has open circuit voltage of 38-42volts depending on what input voltage you give it's internal transformer.

My workshop input voltage on an industrial estate is only 216.4volts AC.

Min you can have in the UK for a 230volt supply is 216.2Vac. Before the grid engineers will come out.


----------------


7018's light up ok on higher OCV - higher voltages - restarting them is the challange....

 

[Jim mcgrath]

I did the other welds in the photo with a rod called super optimal 312-17. I bought some, years ago but I can’t remember what they cost, although I think they may have been expensive. I have only welded with it a few times but It’s a lovely rod to use. Could anyone tell me what these rods are normally used for and why you don’t see them used more often?

 

[wyn]

312 is stainless steel

 

[Talk]

Your welder does not have high enough volts to easily start the ark and keep it going.
Also these rods could be any concoction coming from amazon, better to buy a know brand.
If you do not already know this, then avoid using these rods because a certain amount
of knowhow is required to lay a decent bead which will safely do the intended job.
Use a 6013, I welded low loaders with these and never had a break, much easier to
use on a cheapie welder.

 

[Jack Ryan]

Was there a particular reason for purchasing 7018?

As many have said, they are not the most cooperative of rods. You can use an AC welder but you'd likely need one with a high/low voltage range to give you an 80V OCV.

I's stick with the consensus here, use 6013 - preferably from a known brand.

Jack

 

[trigger3]

ideally you want 90-100 ocv for 7018 but they will still strike up at down to atleast 65 . although they wont strike nearly as well

 

[E T]

ideally you want 90-100 ocv for 7018 but they will still strike up at down to atleast 65 . although they wont strike nearly as well

No, 70V ocv will do nicely for 7018. Even 65V is doable.
90-100V is needed for cellulose rods like 6010 and you need a different VA-curve for those as well. That's why most inverters can't run 6010 rods unless if they have a specific 6010 setting.

 

[zzr1200]

Personally if I were you, I'd make my life a whole lot easier and invest in a 140 amp to 200 amp dc inverter, it will give you much easier arc starting, with an arc which is easier to maintain.

Plus most inverters will run all rods apart from 6010's, you could also have a scratch start tig welding setup in the future for not a lot of extra outlay.

 

[trigger3]

No, 70V ocv will do nicely for 7018. Even 65V is doable.
90-100V is needed for cellulose rods like 6010 and you need a different VA-curve for those as well. That's why most inverters can't run 6010 rods unless if they have a specific 6010 setting.

im well aware 65-70 will do. 90-100 is far better. the difference is nearly 0 stuck rods with 90-100 (even on restarts) , vs alot more stuck rods at 65-70 (especially at restart).
i have two machines . one with 90ocv .the other 65ocv. believe me theres a night and day difference

 

[premmington]

I did the other welds in the photo with a rod called super optimal 312-17. I bought some, years ago but I can’t remember what they cost, although I think they may have been expensive. I have only welded with it a few times but It’s a lovely rod to use. Could anyone tell me what these rods are normally used for and why you don’t see them used more often?

312's are dissimilar's - I use them allot here - they are the rod of choice for bolt extraction. Higher tensile strength than 7018 LoHy's - elongation tolerant - will not crack when cooling with differing metals - rods light up and restrike a treat. Only downside is they not cheap per 4/5kg box.

(just watch the self releasing slag - it will ping off and have you - when you least expecting it)

Dad got me into these - he told me they developed for welding armour plate in the Second World war - not sure if this is true?

 

[premmington]

No, 70V ocv will do nicely for 7018. Even 65V is doable.
90-100V is needed for cellulose rods like 6010 and you need a different VA-curve for those as well. That's why most inverters can't run 6010 rods unless if they have a specific 6010 setting.

"CEL" setting

 

[trigger3]

some machines (perhaps the higher qaulity ones) put out 90-100ocv even with no cel setting

 

[Jack Ryan]

"CEL" setting

I think that depends on the manufacturer.

Neither ESAB nor EWM use that terminology and Unimig don't have a setting - just select MMA.

Jack

 

[premmington]

I think that depends on the manufacturer.

Neither ESAB nor EWM use that terminology and Unimig don't have a setting - just select MMA.

Jack

True... (I actually don't own a welder now that has a cel setting)

My little Miller 160si does not have a cel setting and only a 85 ocv.

Also my Kemppi Miniarc 180 does not have a cel setting and has a 90 ocv

Both will light up 6010's - not that I use 6010s much.

But my Lincoln V205T does not have a cel setting its ocv is very low @ 54volts and it even struggles with 7018's

Voltage is everything if you want to run anything but rutile rods....