Archive for June, 2019

 

Operation: RESTORING BROWN: Vivisection of the Beast – the Summer of vantruck Begins;

Jun 24, 2019 in vantruck

With all of Vantruck’s major build phases being named cheekily after American military operations in the Iraq and Afghanistan wars, (AMEEEEERICAAAAAAAAA), y’all knew this title was coming. ENDURING BROWN documented the struggle to get it back in running order after the Crash of Motorama 2017.  Later, RESOLUTE BROWN saw it become a staple of the Big Chuck’s Van Navy and move from “de-shittification” to “more-goodification” with addition of new fitments such as an overdrive, attending a few  (largely undocumented here) cAr ShOwS usually by just showing up and having everyone assume I belong, and even assuming the role of Company Truck™ in the critical pre-money months of yesteryear.

But, in all honesty, it was missing a lot. Cab rust issues were seriously affecting how I was viewing having it around – the roof became no longer rain-proof at the rusted weld seams (apparently a very Old Ford Truck Problem), making me wonder why I (at the time) had two non-waterproof vans. The paint was globally deteriorating to the point that every wash was turning my towels a light brown shade. And most shameful of all….. I never actually liked the brown-on-brown-on-BROWN paint job anyway. Sacrilege to my fans, I know.

And on top of that, the interior fittings were coming apart with increased use and mileage, reflecting their original cocaine-fueled construction pedigree. One fine day, I was minding my own business trying to get some tacos when the entire CB radio console fell onto my head in the middle of Route 16. I guess the last drywall screw holding the console to the 1/4″ plywood roof liner finally gave out. None of these are exaggerations. It only gets worse.

Yup, just like that, my decision was made. Big Chuck’s Auto Body Center was ready and waiting, and I was going to dive into the beast and cut it open, watching it bleed from every gash. And it’s gonna like it.

Perhaps the most insightful conclusion I’ve made in the past few months – really in the past year and a half after Season 3 of BattleBots …. which I only just now discovered I never actually did an event report for…. was just why a lot of people car as a hobby.

I do consider myself something like a creative person, and I thought that this creativity was generally bottomless and I’d generally be able to design and build things nonstop. It turns out this is more true if all of the things you build are on your terms – for me, that’s been robots, silly go-karts, scooters, and the like, up to and including the half dozen or so consulting jobs I had taken on in the area for friends’ startups and local companies.

When you pick and choose your battles, you tend to win them, creating the rush to fight more. It’s also why winning robot matches is a good thing! However, in the past (roughly) 2 years of the new company, it’s more been like all creativity, all the time, no matter if I think this is a good idea or not because it’s no longer my idea, only 35-45% mine depending on which paperwork we filed. That , like an artist who has to create boring but necessary marketing graphics all day, is what drains your WILL. TO. BE. 

When that happens, it’s difficult to open Autodesk Inventor again and work on Overhaul because I just spent 7 and a half hours trying to work on something else, and know that tomorrow is going to bring 9 hours of the same and 5 the next day with several meetings thrown in juuuust well spaced enough that I can think about something and get nothing actually completed. Then maybe I spent several hours more at home thinking, or late at night wrenching on the company products, metaphorically or literally, with nobody else around to bug me, which just makes me more tired and peeved at the #System.

Well, in that regime of operation, it’s nice to have a hobby where someone else already did all of that work and you have to exercise minimal thought. Just do. I’ve become more accepting recently of the “Guy who works on 1 motorcycle for 5 years”. Before, I always wondered how you can just sit there polishing one engine cover and not do anything else awesome to it. It’s because his day/entire career might be mind-numbingly repetitive or draining, not necessarily by choice, and all he wants to do is get the perfect polish on all of the chrome motorcycle parts I don’t know the word for before having to acknowledge the rest of the family he dubiously signed up for, that one night in his modified van. I hope I don’t keep this up – because at least unlike this hypothetical Gen-X career twilight strawman I’m talking about, I exercise a lot of control over the product and company direction….for better or worse.

(looks over at his modified vans)….. well shit

But I get it. I understand now. Some people car  because they enjoy the performance and tuning process (as I touched on in the bottom third of my accidental engine rebuild post, automobiles have basically every manufacturing process ever invented in them, often because of them) and exploring the often multivariate paths to their optimum solution. Or maybe they never find one and just go along for the ride. But other people car because it is an easy thing to pick up and put down in the limited time available between interpersonal obligations.

I have no interpersonal obligations to speak of, but I sure as damn have much less time to fiddle with finding the perfect hidden motor for my robots. So here I stand, with roughly the hours of 7-8PM to 11-midnight or thereabouts every night, and only about 50% of Saturdays – a.k.a the self-motivated postmodern Millennial with mutually induced career and success anxiety work schedule (what’s the Latin medical word for that?!). What can I get done in that kind of time? I never thought this would actually happen, but here I am with my first real “Project” “Car” so to speak, and another adventure into which I ran into headlong with just enough knowledge to get into trouble but likely not enough to get out of trouble. What will befall our incompletely Byronic Heroes in this episode!?

The events of the past few weeks will be the first in a few stages of this whole journey. It will include:

  • Stripping down the interior and discovering all of its dirty secrets, in preparation for
  • Recovering the rusted areas on the rolled/welded rain gutters and welding patches over them, then
  • Replacing or retromodding the interior fittings which I can’t (or won’t) save, and finally
  • Painting of the whole thing and addendum of dumb truck accessories

But first, let’s rewind a little to the closing days of Operation RESOLUTE BROWN.  Remember it was about making incremental improvements to make it less horrible? You know what’s horrible? Fuel filler necks that are held on by zip ties. Zip ties that break randomly with chassis-bed flexing and end up prolapsing the filler neck out the bottom of the fender.

I bought the interior fittings and (white, even!) doors from someone on Facebook last year, and never found the time to install them (remember self-motivated postmodern Millennial with mutually induced career and success anxiety – look, I ain’t saying it’s right or wrong, just giving the facts. We report, you decide.) until a few months ago. These things were…. let’s call them “Made to Print”. I get the impression the holes were just in-place drilled on the assembly line if it was vaguely aligned, because I could only get 3 of the 4 holes of the allegedly identical model-and-year filler neck fitting to line up – and one only after drilling out the embedded threaded insert nut completely and just using a loose nut on the back side.

Hey, whatever. It closes and doesn’t even look that bad!

The rear filler door and fitting were going to be a little more of a challenge, because…

To make the custom-length Centurion van-to-truck filler neck remotely reach the existing fuel door location, it had to bend and twist more than the hose could handle. This hose was already damaged when I got it, and rotating it upwards sure didn’t make it any better.  It would need to rotate even more to accommodate the fitting angle. I don’t know why Ford chose to put the fuel doors inside the dually fenders in those years.

With a lot of PB Blaster and some coercing with strap wrenches and prybars, I managed to “pre-compensate” for the twist needed to seat the filler neck such that the hose isn’t twist-kinked any more, just kinked. This should really be replaced for real some time – it hasn’t leaked, but I figure the reinforcement wires showing isn’t a good sign anyway.

The rear tank fitting aligned just as badly, again allowing me to use only three screws out of four.

And both fuel doors are now mounted. Instantly, looked at least a few percent better!  Man, the one-year anniversary of the Centurion RCR Episode (now approaching 400,000 views…. yikes) was coming up, and I really wish it could have been in a better state of De-Shittification back then.

If you’re detail oriented, you might have noticed a trivial change that magically appeared in the past few photos. Go ahead and look again at the past five photos!

Check these out. Around the time I signed on for Big Chuck’s Auto Body, I started more seriously shopping for truck accessories since I would have a less-frozen and less-seagull-dropping-covered place to install them. One of the issues that Vantruck has had, in my assessment, has been “Too Little Ass”.

What I mean is that the thing sits so high that it’s mostly tires looking at it from the back.  Just look at some of the drive-behind shots in the RCR episode.

The aftermarket step bumper I used to replaced the wrecked original is rather short in stature, and a conflict in its height versus having to access the existing van-frame trailer hitch for towing the company trailer meant I had to flip my mount and bring it up even higher. It just looked rather wrong, like not enough is going on, not truck shaped enough.

I plan to fix the bumper issue with a custom rear deep-drop step-and-tow style bumper (see: Stage 4 where I add horrible truck accessories that I haven’t gotten to), but in the mean time…

I am reminded of why I hate the idea of buying horrible truck accessories. Because they’re all overpriced and shitty for what they are. For the low ruble amount of $125 I got these rubber sheets that have the thinnest diamond-tread plate aluminum ever riveted to…. no, I HAD TO DO THE GOD DAMNED RIVETING. I could bend these sheets not just by hand, but between my fingers.

Dunno what I was expecting, really. If I still had 24/7 unfettered access to a “Milk my tuition back dollar by dollar” machine (also called an abrasive waterjet) I’d probably have made my own from 1/8″ or something. Nah, College Charles would have done 1/4″ for dramatic overkill.  But for now? Whatever, more money than time or sense.

Yeah, not to mention the braces were bare, uncoated steel. They’d melt away in one winter. So I did what I do best – paint them Miku Blue with leftover Overhaul paint.  Primer, base, and clear. These will last for a while yet!

Because it was actually still the middle of winter (what I call Winter begins in late September and runs until mid May), I had to give the paint some boost to dry and cure properly.

 

While snooping out the underside of the bed for where to drill the holes, I discovered a fun archeological fact about this bed I bought.

It had the exact model or a very similar model of mudflap.

The holes were already there. Both the underside and wheelwell one.  Well, now I understand what those holes were there for! I might start playing this game on purpose – try to “Guess the Accessory” based on the vestigial hole pattern!

The truck this bed was on definitely used to have a Gooseneck type hitch, because of the, you know, 4 inch diameter hole drilled right in the middle. On my long-term agenda is to re-add such a hitch, even if I have nothing worthwhile to tow, because truck cred.

The convenience was short-lived, as I quickly discovered that the rubber was cut assuming the F-series truck frame dimensions (33″ wide) which are a good 9″ narrower than the van frame (42″ wide). It just meant I had to move the thru-holes about an inch or so over for them to clear the leaf springs.

And…. not bad. The Ass Factor has substantially increased, and with it, the Truck-Shaped Coefficient. The higher your TSC, the more truck-like your truck is. Get it? Good, because I’m not going over this material again; you’ll have to work with your TA in recitation before the exam on Tuesday which will consist of one question only: What color is BROWN?

I finished all of the previous installation work before Motorama this year since I wanted to use that as an excuse to finally make the thing presentable. Externally-imposed but still artificial deadlines, you say!

We can now move on to the true beginning of Operation: RESTORING BROWN.  I spent a day or so after being beaned by the radio console to kind of outline the scope of the whole project and reaffirm my motivations. In short,

  • The radio console falling off will be the triggering event of pulling apart the interior
  • This has to happen because the rain gutter rust had, in my opinion, reached almost irreparable levels on the left side in three locations – the rear near the stitch seam, the center over the double windows, and over the driver side door
  • Repairing it will necessitate hotwork (welding, grinding) and I definitely don’t want to set the interior pieces on fire; I had to take the all off to investigate what will be nearby the weld site
  • While the interior is apart, perform upgrades and make changes; at least lay the foundation for changes I want to make so it can be closed back up
  • Repair or address all remaining rust sites on the cab in the interest of a full repaint; leave stuff in primer or some spraybombing
  • Shop around for a repaint quote or stop being scared and do it myself.

During this process, I had to minimize the amount of “immovable object” downtime so I had to plan my moves carefully – just taking everything apart with reckless abandon is how you end up with a Craigslist pile. I bought my vans as Craigslist piles, I should know this.

I decided a good brainless task to start on was going ahead and dismantling the interior, since at the time I was waiting on my welder and also needed to do research and think about how to attack the rain gutter rust. Learning more about the interior might also inform future changes.

First operation was to begin unscrewing all of the interior fittings, like the sun visors, trim pieces, and the cabin lights.

At this point I had no idea how anything was attached, so I carefully marked and retained all of the screws I removed. The answer: 1″ long self-drilling sheet metal screws. Just power zipped in there.

I sighed, and pressed forward.

I removed the passenger-side B-pillar upper trim to release another section of Centurion-special upholstery and….

 

Uh oh.

 

Literally duct tape has been found as a construction material. This wasn’t recent duct tape by my investigation – it was rigid and crispy, the kind of duct tape that only could have gone into it from day one.

I signed, and pressed forward. I see how this is going to go.

The stained wood roof….arches? are how the individual panels are retained. Under them are some more edge screws that hold the interior panels to the OEM steel roof beams, most of which are flat-head and were “driven through” the fabric so I couldn’t see them. I had to carefully examine the surface with a flashlight and catch reflections of the screws.

Alright, down comes the front portion of the interior roof liner, and…. I see duct tape from here. Oh no.

Oh no.

You know the canned movie/cartoon scene where the hero opens a door, chest, box, or some other cavity-laden plot McGuffin, makes a face, and then looks away back at his consortium of misfits and goes “It’s worse than I thought” or “Don’t look in here”, and closes it again?

That.

Right, also, do you see what I mean by 1/4″ plywood? It’s literally just stapled “Sagging Headliner” material on 1/4″ regular-ass 1980s plywood. Probably made from cocaine trees. I’m going to keep making “80s cocaine” jokes, despite having nothing to do with either subject matter.

 

Yep. Okay, moving on. I anchored everything back by 1 screw so it would stay in place; I wanted to see how bad the rest of it was.

To remove the rear panels, I had to first guess what order Centurion fit everything in. The answer is the worst possible order, a.k.a how I’d have done it too.

The driver’s side double-window panel went in last. You can tell since it overlapped the edges of all the other panels on that side. This meant to release the (what i now call) #2 and #3 roof panels, I had to remove it first. To do that, I had to release a significant portion of the driver’s side B pillar including the seat belt anchor bolt and both conversion van window frames.

These window frames were, let’s say, clearly not intended for the Ford van, as they had a different curvature than the outside of the body. This was hidden by the fact that the outer sheet metal to interior drivers’s side wall panel distance was about 3 inches filled with fiberglass batting. The curvature was then forced by elastic averaging beasting it with 17 1″ long self-drilling sheet metal screws each.

If any of this is able to go back in after I was done, I am starting a van restoration shop for real.

By the way, I went full long sleeve and respirator for this op – because the first time I popped the roof down, a cloud of orange decaying urethane foam dust and fiberglass particles rained down.

So how did your co-founder die? Miner’s lung. How did he get that? Working on his van. We don’t talk about it. What a conversation for your Series A funding round party.

 

Investigating some of the artifacts, such as the rear cabin light module, was a source of entertainment also. A lot of companies made RV accessories in the 1970s and 1980s, and most of these companies (Centurion included, in the end) are no longer around. Well, I found out why one of these lights always kept falling off: Because the HOT GLUE JOINT retaining it had given up.

You know what, maybe ya’ll fucking deserved to go out of business.

With the driver’s side wall panel pulled apart, and all of the roof panel screws released, it was time to unveil more of the Fiberglass Flabberglast. The silver foil tape isn’t OEM – I had to add it, very fittingly of course since it’s designed for insulation panels, because the two rear pieces kept trying to fall down on me.

I had known that Vantruck was insulated for a long time, but didn’t know how good of a job they tried to do until now. The side walls and rear endcap wall are very well filled, but the roof just had these cut rectangular chunks. Better than nothing I suppose, and it made me want to install the rest inside the gaps once I was finished in here.

Gee, thanks. Just pull naked wires against exposed steel edges. Yup, who cares about strain relief?  Who cares if your product is a fire hazard if the company will go under soon anyway!?

The condition of the roof underside wasn’t that concerning – not as bad as these photos make it look. It looks like rust caused by temperature cycling and condensation, and was entirely surface. Will it become an issue one day? Probably. Do I care enough right now to rip out all of the fiberglass and try to clean/remedy it? Nah, I had much larger, browner fish to fry first.

As a final step in this adventure, I decided to just rip the scab off and reveal the full Lovecraftian wirebomination that is the #1 roof panel.  I knew it was going to be bad, since all of the five “I am a large truck please thank you” DOT lights on the roof are wired in here, as well as two internal cabin lights and all of the CB radio and console buttons.

Up your nose, here we go…

 

Boy howdy did this get out of scope fast. I haven’t even touched any rust yet! In the coming days, I would switch mental gears and just grind and sand stuff while thinking of what I could possibly do to make this any worse.

 

Beyond Unboxing: Inside a Very Chinesium Mini MIG Welder

Jun 15, 2019 in Beyond Unboxing

Welcome to another episode of Beyond Unboxing, where Charles buys something almost solely for satisfying his morbid curiosity. Generally, it’s something made of pure Chinesium (except last time) that I’m trying to press into service for something completely unintended, and I’m more interested in a part inside rather than the thing itself.

This time, it’s a little different. What Big Chuck’s Auto Body Center has been missing for the work I want to do in it has been a welder so I can start doing some sheet metal repair on the van fleet in earnest. I began shopping around in earnest a few weeks ago for a MIG welder, which would pretty much handle everything I would typically weld. It would have to be at least somewhat shitty, since we paid top investors’ dollar for the company welders, but just not shitty enough such that it makes me want to “borrow” them periodically.

At first I was just considering a used Miller or Lincoln unit with dual voltage input since Big Chuck’s Auto doesn’t have any 240V or 3 phase – I only have 120. Hella butts 120 (several independent 50 amp circuits fed by what looks like a 200 amp breaker) but still only 120, and most welders will power limit automatically. Buying a giant step-up transformer was, of course, one workaround which I didn’t want to consider, and buying a dual-voltage one would also be expandable for any future shops I spider-hole in. Recent vintage ones will usually go for somewhere in the upper hundreds to low thousands, and usually quickly since they’re desirable. But wait….

Hold up, trap. This is me we are talking about here. I’m the king of spending more money and putting more effort into finding a suboptimal solution than just spending money on something that works. Just ask my van fleet and all my robots! Anyways, just buying a welder which actually works has no hack value. I came to this startling realization and decided I needed to do me: Go explore the horrible Chinesium product market and see what the bazaar of the world has to offer me for very low dollar. After all, I could just borrow the company MIG welder for a day and….

So! I spent an evening reading up and studying about Shitty Chinese MIG welders. Heaven forbid I put this much effort into actually studying something that’s useful for society, right? Here’s what I learned!

The Chinesium welder market is generally split up into 3 Gaussian bands for pricing. On the very bottom shelf, you have stuff like this…

 

These things are usually not even MIG, just flux-core only with no gas handling ability. They also don’t have discretely adjustable output power like a knob or setting keys, but just have 2 big switches which rearrange taps on an internal transformer to get you 4 vaguely different voltage and current settings. I’ve used the Harbor Freight Special of this kind before, and they do work with some getting used to, but this wasn’t even worth looking at for me honestly. No, not even the cheesy handheld welding screen was worth it.

Up around the $250 range, you start to get actual adjustability and gas handling, though some are still flux-core only……… but you have to read the description to find out! The torches are still usually hardwired in (this is where I learned the difference between the various welder output connector systems like Tweco style or “Euro” style torch fittings) – guess there’s not money in that product dev budget for a nice chunk of leaded brass.

For this price and less you begin to see the “inverter” based ones – cheaper ones if you just search Inverter Welder will be stick only or a combo stick/TIG machine. These are actually pretty cool in my mind, just I don’t have a use case for them. MIG needs a wire feed system so it’s usually pricier.

And getting close to the “Please buy a used brand-name machine” price range is when you’ll see the whole feature set of inverter machines with adjustable voltage/current/wire speed, gas handling, removable torch, and the like.

I decided to play a game and find the least expensive machine which had:

  • Knob- or button-dialed variable voltage and wire speed
  • Removable torch
  • Inverter-based
  • Dual voltage advertised, or at least I suspected could be dual voltage capable.

This last part is important, because I had a sneaking suspicion that these Chinese inverter welders were stupid enough that they would run on 120V even if advertised for 240V.  A lot of inverter machines were being advertised as 220/240V only – which was weird, since the way I know these things should be working, it doesn’t matter. Perhaps the Value Engineering had really made their power supplies dedicated to one voltage or another, or perhaps they are just seeking different markets. Either way, we fast forward ….

…A few days! What? It turns out that this thing is actually Fulfilled By Amazon. Thanks, Jeff Bezos! I was expecting to continue haunting the market for another 2 weeks or so while gently regretting not just getting a usable machine off Facenet Marketplace.

So this here is a “REBOOT” branded … box of something. There’s a crude lineart of a dude welding something – or perhaps shooting his death ray at something. It says Good Quality on it. You know, much like my LED headlights say ‘DOT” on them, writing Good Quality on the box doesn’t make it necessarily true. But, optimism shall prevail!

As of this writing, you can find this thing on eBay for $237.50 with FREE! shipping, which for a box this size is a nontrivial value.

So I’m gonna scoop my own Beyond Unboxing real quick. I actually got this thing so fast that I didn’t prepare anything else, and I was already at Harbor Freight for a company run and decided to unpack it to see if I could get any accessories that fit it right away.

This thing is… deceptively small. The company welders are all pretty beefy, and before that, the machines I’d have access to were not inverter units – they were older transformer ones. It’s in fact so small it can only take the 1kg wire spool size. It’s a very easy one hand lift. Definitely color me surprised and somewhat dubious it contained anything of value.

Alright, and we are on the operating table. This is the contents of the box. The unit itself, a ground clamp, a stick electrode holder, a length of PVC gas hose, and a 1kg spool of mystery meat flux-core wire to get you started. They really know their audience! Free consumable since you probably designed the thing to last as long as the spool does for the guy who buys this and welds 1 thing.

Let’s begin shucking this clam. First and foremost, let’s get this out of the way: Every cable on this – ground wire, torch output, and power cord – is copper coated aluminum wire.

I’m sure it was invented with the best of intentions. It’s light weight, it’s softer and easier to work, and it makes better use of copper conductors at high frequencies because of the skin effect.

Oh, and it’s cheaper. Did I mention it’s cheaper?

For the same gauge, make sure you realize you’re only getting 2/3rds the conductivity. When buying any questionable pedigree wire product, always take a cross section sample and ensure it isn’t bright silver colored, and strip a section and scrape the top few strands with a knife facing backwards. If it also feels too light to be made of metal, it’s probably CCA.

Basically every car audio product you buy on Amazon will use CCA wire to mimic the same gauge copper. This is just fine and dandy if you buy things by nameplate power and never, ever actually need all of the rated amps of a copper wire of the same size.  Listen to the man whose company product dynamometer results were thrown off 30% because we just threw the 4AWG audio cable we wired robots up with at the damn thing and actually tried to push 250 amps through it.

Anyways, I’m sure it works fine for the limited duty cycles and shorter runs (because these included cables and torch parts are NOT the whole 10-12 feet you’d get otherwise!). This is the rant of someone that is very butthurt and traumatized by one specific issue. I literally just finished yelling at a vendor recently for using car audio cable on some custom battery packs I commissioned because they came through silver – fortunately, after a lot more examination, they were just tinned well. I like my wire brown.

 

The drive mechanism is pretty generic, with fiber-filled plastic everywhere. I was hoping for a stamped metal or at least cast unobtanium drive system, but even low end brand name units have plastic wire feeds now.

What peeved me more was that this torch was hard-wired after all. The huge strain relief grommet made it LOOK like it had a Euro style connector on the output; but alas, it was just hiding the truth.

We’re off to such a good start with this one! Oh boy, this means it will be amazing.

I do have some good news – the Harbor Freight Vulcan series of MIG welder parts, such as contact tips and gas nozzles, do fit this torch. I figured the Law of Chinese Product Packaging Inertia would make this the case.

On the left is what it came with, and on the right are the Vulcan parts.

The gas hose is an 8mm push fitting; no 1/4 NPT here!

I took apart the drive mechanism to see if it would be plausible to convert the thing to a connector (so I can eventually attach an aluminum-dispensing spool gun on it) – not really, all of the cables and gas hose actually just disappear into the bowels. The cable sleeve is pretty much just a bike brake cable sheath.

My goal with taking the lid off was to investigate if there was any plausible reason why it couldn’t run on 120V. It woke up when I plugged it in, but I didn’t install any wire or try to weld anything. Besides, I was curious of what kind of Value Engineering had gone into the other parts. The case removal is easy – just undo all of the sheet metal screws.

There’s two more hidden under the handle too.

And here’s one side of the goods! The drive unit is a little speed-400 type motor, but higher voltage, feeding into a spur gearbox. This thing looked to be an OEM part of some sort you could buy – it’s genericized on eBay and other places as “24V wire feed motor”. The controls are up top, and the big money power is on the bottom.

All of the boards had this name written on them. Arcsonic seems to be the actual brand name/OEM of this unit, along with many others that look like it. I’m glad it was this straightforward!

This smaller board is the rectifier assembly. Just a bridge and some capacitors here, no fancy power factor correction.

The back side of the board – the relay is the gate for AC power to enter the rectifier and DC bus.

The part of this thing that can be called the “Inverter”, I suppose. Most of the time when welders say “inverter based” they mean this kind of buck converter architecture .  In this thing, the rectified AC mains power enters on the left side. It then gets chopped by the IGBTs under the left hand heat sinks to yield a lower voltage. It’s the same topology as almost every motor controller. The large donut on the right is an output inductor to smooth the current ripple.

Actually, looking at the backside of this thing, it’s more properly called a half-bridge forward converter. There is an isolation transformer in the middle between the input and output to step the voltage down in lieu of modulating the duty cycle across a wide range. The exact mechanics of what a half-bridge converter is are beyond scope here, just accept that it made me go “oh, neat” and can be highly efficient.

 

The control board is almost all discrete and thru-hole components. This design must date back quite aways – not being a welding historian, I can only guess it’s lifted from a 90s to 2000s era inverter welder of American or European bloodline. I wasn’t interested in diving into what it did here – pretty much just scanning what the logic power supply looked like.

At this point I was convinced that it might be stupid enough that I can just run it on 120V without issues, perhaps just taking a hit on the maximum output voltage. That’s mostly why I was staring at the power stage, since some architectures will prevent the duty cycle from changing enough to accommodate a 50% reduction in bus voltage; if not, it could be smart enough to error out of it detects a duty cycle increase above a certain limit. The design of the half-bridge forward converter is such that it’s pretty input voltage agnostic as long as your driver circuitry keeps working.

I began putting the thing back together and briefly wondered why a MIG welder would have both a volts and an amps knob – before remembering this thing can also do stick welding. In MIG mode, as I tested, the Amps knob just controls wire feed speed.

Continuing the reassembly! The torch is really, really hardwired in – if I wanted to smack a Euro fitting on it or something, I’d have to deconstruct that whole signal wiring harness to disconnect it from the control board. Not worth it, really. If you wanted expandability into the Chinesium aftermarket, this is probably not your unit – I also didn’t see any easy way to cut a spool gun into the control system. I suggest, you know, buying a real welder.

I decided to go ahead and arm up the mystery meat flux-core spool  and actually get some welding done.

So, Big Chuck’s Auto Body came with something I call “Frank, the I-beam”. It’s a 16″ tall structural beam that used to be 24 feet long. Just an entire I-beam, hanging out and squatting on the floor eating all your leftovers and smoking all your weed, the underachiever. Early on, I hoisted it onto a set of 4 car dollies so I could at least shove it into a corner. I later asked some friends to come over and have at it with torches and cutoff saws – they took most of it to make things like anvils and…. gantry cranes? I didn’t really ask too much.

Anyways, I kept 6 feet of it for… whenever I need an I-beam, or something. Right now, it’ll be welding practice. I was going to crank this thing up all the way and just deposit steel.

Well, I definitely own a steel ball spraying machine.

My history with flux-core welding has been very spotty. I’ve usually just been handed a machine in some field/competition/informal gathering and told to fix this or that, and it was filled up with flux-core wire because no gas or infrastructure to support it and no willpower to change that.

It’s always just made a mess and been horrible, and I always wrote flux-core off as a trashy third-tier welding process.

It turns out, you need to use Electrode Negative mode with it, or “straight polarity” welding. First, that’s a welding industry legacy term, because to everyone else, “straight” or “positive” polarity means something with positive voltage is touching it. Who the fuck knew!?

I sure didn’t – since I avoided the process like I avoid college town liberalism, i.e. once and never again, I never did research into it enough to find out that LITERALLY EVERYONE WHO HAS HAD ME TRY TO USE A FLUX CORE WELDER HAS BEEN WRONG.  You don’t just insert flux-core wire into a MIG welder and start firing away – well, you can, but it would make more little steel balls than weld.

This thing lets you switch the polarity of the torch and the return clamp manually. A more sophisticated machine might have a big ol’ switch on it to do so. Either way, by searching “why is my flux core welder shitty and raining steel balls everywhere” I learned a thing.

Yep, so that vertical line on the right is the first decent looking bead I’ve ever made using flux-core wire.

In my entire life.

You know, past the toxic cloud of flux vaping upwards at me, and the need to constantly wire brush and clean up your weld, it’s actually not bad! I see that, much like people fool themselves into liking India Pale Ales, people also fool themselves into liking flux-core welding. I made several more fine-ass looking beads after this, too.

So, the verdict? I had the machine cranked out to the max on both voltage and wire feed during these tests, and it handled that admirably. It’s obviously not pushing enough power on 120V input to hurt itself, nor to trip a convention 15A breaker. I deposited steel (welding implies it was usefully joining metals) for about 30 seconds straight crossing the entire I-beam width – that was a nasty looking slug by the end – and the machine didn’t throw any angry lights or stop running. In the near future I do want to drag it over to the new shop and try putting an Overhaul wedge together using 240V mains, and see if it wants to go back on vacation.

In the end, this “220V” Chinesium inverter MIG is proving itself quite handy on 120V. Luckily, it won’t be principally welding I-beams together in Big Chuck’s Auto Body. Instead…

 

IT BEGINS.