Re: Welding, what do you know?

Posted by sgtslag on
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Welding-what-do-you-know-tp3416351p3417736.html

I've been checking out books, and DVD's, on welding, from my local library.  I've learned a lot, but I don't have a welder, yet.  Hope to get one soon.

For arc welding, be aware that you will need either a 220 VAC/20+ Amp circuit, or a 110 VAC/30 Amp circuit wired into your garage, or shop, or wherever you plan to weld!  This is not something you can skimp on...  Make sure it is wired according to code, because otherwise you might burn your house down.


I've been looking at the different types of welders, and I agree, wire feed welders (with/without gas), are the easiest to learn on.  Stick welders are among the least expensive, and are extremely versatile.

For higher duty cycles, you will want to make sure your welder is an Inverter type:  this is a more efficient type of power conversion, from line AC current, to low voltage, high amperage, DC current, which forms the arc.  While it is possible to find plans on the Internet, to make an AC, Buzz-Box welder, using discarded, high voltage transformers harvested from microwave ovens, they are not the best.  Note, however, that these home-built units, are strictly AC arc welders, and they are very low efficiency, and low duty cycles.

On top of the welder, and the appropriate sticks/wire, you will need protection from the harsh UV (ultra-violet -- harmful out to 40 feet, according to one book), and IR (infra-red, will burn exposed skin, very quickly), as well as the gases, air-born particles (metal particulates -- very bad!), and the light (all of the light produced can burn your eyes...)!  Welding can be quite dangerous, so invest the time to research the potential hazards.  And be safe!


There are books aimed at beginners, which even suggest projects for beginners:  a welding table (metal, allows welder to put their grounding clamp on the table, rather than the work piece); welding blinds, or shields, to block the light, UV, and IR, from affecting anyone nearby; as well as other things such as shelving units. Your library is your friend -- it will save you a fortune on books that might be useful, or might be a complete waste of your cash supply.


The thing to remember about arc welding, is that your supply voltage is not nearly as important as your output current, for welding, and the arc.  The thicker the metal, the more amperage you need, not voltage, for the arc.  If you can get 100+ amps from a 110 VAC welder, it will handle near 1/4" steel, if I remember my tables and charts correctly.  The 100 amps in the arc, is only 60-90 VDC.  The efficiency of the welder refers to its ability to convert high, line AC voltage, to high amperage, low DC voltage, for the arc.  There is no doubt that 220 VAC circuits can supply more amperage, and power, overall, but it depends on what level of welding amperage you need, and how efficient your welder is at converting it.

The Inverter type of DC welders, run at 80%+ efficiency at converting the line AC to welding DC current.  The Inverter types are using very high amperage, solid-state electronics to convert 80%+ of the AC power to lower voltage DC amps to create the welding arc.  Non-inverter, DC welders are in the 50% range of efficiency, which means they can only put out around 60 amps, on a 110 VAC welder.

There are a lot of DC welders available on e-Bay, both 110 VAC, and 220 VAC units.  If you are very confident you will be using it frequently, then invest more money into your unit.  If, like me, you will be pursuing it more as a hobby, with uncertainty as to how much welding you will be doing, then perhaps an inexpensive, 110 VAC stick welder unit will be a better choice?  Much to consider.  Here is the model I am looking at:

http://www.ebay.com/itm/370274725414?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_594wt_952

Note that this unit does not have the leads needed to weld -- you will need to purchase them separately.  Also note that this unit will function on a 110 VAC/20 Amp circuit, but it won't push 110 Amps into the arc, without a 110 VAC/30 Amp supply circuit...  My garage has an anemic, 15 Amp/110 VAC circuit.  It needs to be upgraded, even without throwing an arc welder into the mix!  I really need to get an estimate from an electrician, before I do anything else.


Again, before buying any welder, find out what the power circuit upgrade will cost you...  Then factor in the cost of your desired welder, and that will give you a ballpark figure of cash needed.  Then add in leathers, gloves, respirator, welding mask, and miscellaneous supplies (don't forget about venting the fumes, and blocking the light (UV, IR, etc.).  Cheers!