Oxy/Acetylene torch kits-Harbor Freight?

[scottiniowa]

A note - when you tack weld the 4130 and the tack metal will normally become harder than original.  I found when coming up on the tacked area your are going to need more heat at the tack site.  So that is going to mean adjusting the gas or speed of weld at the tack site.  If you do not make an adjustment of some kind, you will find yourself welding up on and over the tack and having an unsightly area at the tack site.  Just a thought and would be something to practice on a couple times before hitting the final tube welding.  Yeah, you guessed it,,,, I found this out on my own took me a bit to figure out what was happening.  You will find this happening around the multiple tube points where your welds start coming together also.  After a while, and some practice at filling up burn holes, I found I preferred a bit more heat, kept the speed up on clean tubing, and I could just slow down a bit coming up on the weld... Just work the puddle and you will be fine.  The secret is work the puddle.  Try to keep the puddle a consistent size and most of the other stuff like speed, torch heat, rod feeding will fall into place.  Of course this actually works with most other types of welding also, so you may be familiar with it already.   Have Fun

NightEagle @ BlackHutOps

Some additions to above

• [font='Segoe UI', 'Helvetica Neue', 'Liberation Sans', 'Nimbus Sans L', Arial, sans-serif]A note - when you tack weld the 4130 and the tack metal will normally become harder than original.
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with the added words of tacking with MIG, then gas welding the MIG creates HAZ  Heat affected zone- which largely becomes mute with your follow up gas welding. but certainly true if you have wire that is not correct, a quick check of your wire make up will tell you.  Not very many wires are clear down in strength we can live with.  i.e.  45-70 tensile rating. 

•  I found when coming up on the tacked area your are going to need more heat at the tack site.  So that is going to mean adjusting the gas or speed of weld at the tack site.  If you do not make an adjustment of some kind, you will find yourself welding up on and over the tack and having an unsightly area at the tack site. 
  

All the more reason for the practice coupon explained earlier.  

•   You will find this happening around the multiple tube points where your welds start coming together also.  After a while, and some practice at filling up burn holes
  

by watching your puddle  (ZEN of welding) burn holes should be very very seldom. 

[Hugh Sistrunk]

I use what I think they call '70 pounders' or something like that.  The Oxy bottle is about 4 feet tall and the Act a bit shorter as you will use Oxy at a higher rate.  I had some in the tanks at the beginning, and seems like I refilled them twice during the build.  I have mine on a cart so they can be moved around with out them falling over... But, I can say, during my build, with standard gas hoses coming from the regulators and the smaller hoses on the Meca Micro Torch, it was never necessary to move the tanks from a position off to the side of the build table.  Just be sure the tanks are securely anchored to prevent them falling over.  A falling tank and broken valve with the pressure the gas is under will make for a VERY exciting day for you, your neighbors, your shop walls, passing cars, pedestrians in the area.  Secure the tanks - If you do not secure the tanks, be sure to get us some video of it for the rest of us to watch.  :-)

NightEagle