Welding, pumps, and solenoids ...

I bought my welding machine last week! I splashed out on an ESAB MIG unit (very reputable brand). The 3 options available were a normal stick/arc welder, a MIG unit, or a TIG unit.

For stainless welding TIG is generally considered the best, but this requires 2 hands coordinating the arc and feeding the electrode in. It is also generally considered the hardest to do well and since I am not even a welders a-hole, I figured to steer away from TIG. They can also be quite expensive machines.

The other end of the scale was a normal stick welder. You can get these units reasonably cheaply and you can get stainless Electrodes with flux on the outside, but it can be challenging to get a decent weld unless you have a heap of practice (welding is an art!). For stainless, stick welding doesn't necessarily provide great shielding gasses from the flux (compared to MIG and TIG) so there is a risk of corrosion creeping into the weld as well.

So the other option was MIG. MIG actually isn't the most recommended type of welding to use for stainless as it generally requires a specific blend of shielding gas (either very expensive tri-mix or a combination of argon and CO2 in roughly 98:2 ratio) and these gasses can be expensive. It also is said to be not the best on thin walled steel such as my kegs so that put me off a bit, but when all things were evaluated, I went with MIG. The main reasons I went with a MIG are that even a welders a-hole can generally get decent looking welds with a MIG unit, I can get reasonably cheap argon in disposable bottles from a shop nearby, you can use pure argon and get reasonable welds (even if they are higher than wider in general), the stainless qualities can be retained, and if you get a good unit, do plenty of practice, know your settings of wire speed vs voltage, weld in a special way for thin materials (focus the heat onto the coupling rather than the thin walled keg) then you should be able to do ok. It is also a good unit to use for general fabrication work down the track. From what I read, you generally get what you pay for with MIG units and the cheaper ones will give you a lot of grief with wire feeding, so I got a very reputable ESAB machine - Origo C141 to be precise!

So I got the welder, got some argon shielding gas with regulator, some stainless wire spools, welding helmet, and all the other necessary stuff and lay down some welds tonight for the first time. I didn't focus on anything critical or that will be on full view, and the welds were ok I guess, but I just welded up one of the brackets that will support one of the burners. I think for my first welds they weren't too bad and I think all the research I put into welding (wire speeds, gasses, push vs pull technique, whip vs weave, weld fit up, tip stick out distances, tip clearances, etc etc) will pay off.

I also picked up my awesome pumps for the system today as well as my gas solenoid valves! The pumps are the brewers standard March pump! These are the 809-HS pump and are a food grade, magnetic drive pump that will be responsible for transferring and recirculating various fluids from and between the different keggles. The solenoid valves will open when told to by the temperature controllers and let gas to the burners for heating the HLT and MLT. They are a NC (normally closed) valve so that they only need to be energized when gas is needed for burning.

So all in all, even though no major progress has been made on the brewing system, I feel as though there is really not much stopping me now from getting this beast on the road. Once I have done some more practice welds on less critical items, I might start tack welding the frame together and get that done before trying out some welds on the keg lids to ensure I have the wire speed and voltage correct to avoid any blow-outs on my precious kegs!

My ESAB MIG unit

The disposable argon gas bottles. Hopefully these will last a decent amount of welds.

My welding station ... with keg stool of course!

Not bad for my first welds.

The other side of the fillet.

My beautiful magnetic drive March pumps - the brewers standard!

My solenoid valves - clever things!