Snowmobile Tilt Trailer Build welding project – Day 4
I’ve learned from removing wear bars on Mining equipment that I can Air Arc Gouge happily for hours on end. Happily. Even with 3 other gougers going. But focusing while my infant son is crying? – near impossible. My brain really is chemically alterd to respond to him. Experiencing just how powerful that is, is incredible!
I used my little Mastercraft FCAW welder to tack the frame together and – I know, I know, – But it went surprisingly well! I just couldn’t help myself and used it to run all the 3″ verticals. My cuts were not exact which left a little gap on the inside of the mitered corners when I squared the frame – perfect for complete penetration and fusion of the weld and a perfect job for small FCAW.
The machine came with .030″ flux cored wire and .023″ solid (MIG) wire. In mining we usually call wire that small ‘micro wire’ with .045″ our ‘small’ sized wire. Running 1/16″ as ‘normal’ for days or weeks on end, these smaller wires really do feel ‘micro’. BUT the micro wires are great for at home (ie: exhausts) and beginners! So I’m giving them a chance.
Todays Welding Progress
The 14 verts where the 2″ x 3″ HSS frame members join.
Tacking went so well I cranked my little Mastercraft machine to ‘MAX’ Voltage and 7 1/2 ‘WIRE FEED’ (…SPEED I assume they mean.)
The speed at which the machine drives the wire out is directly related to Amps. This article from Miller Welds does a great job of explaining!
What 7 1/2 and MIN/MAX means in actual Amps/Volts I don’t know. Getting a good balance is why welding is a skilled trade because settings are a guideline and each welder has personal preferences within those guidelines. We are Human.
I understand why the manufacturer does this – to try and simplify the process – but I wish they wouldn’t. Unfortunately it does not help to relate anything to whats electrically and mechanically happening which only creates further confusion for people new to welding.
I ran the 2 front outside corner verticals and was worried for a minute. You can see below a spot of porosity at the top and what look like ‘worm holes’ at the bottom. Yikes
Luckily both turned out to be surface defects I removed when grinding that outside corner flush and prepping the top flat weld. The 2 front outside corners are the ONLY welds on the whole trailer I will grind flush.
My Mechanic Dad loves everything to be smooth and this is an ongoing argument between us, but a well done convex weld is always going to be stronger than a shitty ground down weld – even if it LOOKS better under paint.
Because I’m confident in my welding and have left all other welds whole, I’m willing to sacrifice these 2 for looks.
Welding today was dirty and spattery like all FCAW and, because of the small wire size and relatively low settings, it was slow. So slow the defects above didn’t surprise me and I am worried about cold lap.
Cold Lap or Overlap
A weld defect where the edge of the liquid weld folds over and does not completely fuse with the material or weld below. It can happen in all positions.
From CWB Weld Discontinuities and Causes, the definition of Overlap:
- “Overlap The protrusion of weld metal beyond the weld toe or weld root.”
- “Overlap is a condition where an excess of weld metal exists at the toe of a weld beyond the limits of fusion. This condition produces notches that are harmful due to a resultant stress concentration under load, and, in the case of a fillet weld, may actually reduce it’s effective size. overlap has the ability to mask incomplete fusion.”
I worried that the slight side to side movement as I progressed upwards would cool or solidifiy so fast that the next movement over is essentially a new weld. Each horizontal deposit could then be thought of as a separate weld pass and have more potential for Overlap.
Leaf Spring Spacers Installed
I installed the leaf spring spacers lining each up at centre marks just before tacking in place. This what the drawing calls for. I guess I just have to trust its not too ‘tall’ and far enough back to put weight on the ball joint.
I won’t get to weld them in today so I can think on this for a couple days.