Backyard Metalcasting (2018) | Hacker News Reader

Backyard Metalcasting (2018)

backyardmetalcasting.com

94 pointsishtanbul79 comments

In my (admittedly limited) experience metal casting is a waste of time if you want to produce usable parts. It never goes right. It always has porosity. It very rarely even fills the entire mould.

And preparing the mould and heating the metal takes forever, so it doesn't take too many failed attempts before you have sunk days into a project with nothing to show for it.

It's fine if you just want to cast metal shapes as a hobby, knock yourself out. But if you are casting because you want to make parts that you can use, then you're better off machining them out of solid material if you can. You'll save yourself time and trouble.

So from your reports (porosity, not filling the mold) you were likely running into 2 very common issues, one easily correctible.

For porosity, especially if you were using aluminum, that is very likely from using the wrong alloy. Trying to remelt aluminum cans or extrusions especially will produce very porous castings. Start with a known-castable alloy, the easy way is to start with scrap that was previously cast. Look at the original part for signs it was cast, that doesn't tell you the exact alloy but it does tell you that it can be cast.

For the not filling the mold, that is shrinkage. The metal contracts when freezing, which can cause the part to be undersize or have large voids. This is fixed by proper mold design, which is a surprisingly large topic and a bit of an art as well and can't be covered in a single topic. One thing to look into is adding a riser, a larger chunk that is designed to stay molten after the part has frozen to concentrate shrinkage.

DIY metal casting definitely can be done. Not everything is machinable shape wise, casting allows you to make things that are either impossible or very hard to make out of a single billet.

But like any other skill at this level of complexity it will take substantial dedication to be able to do it at a level where you can do it with a useable degree of (repeat) accuracy. Even real foundries test new molds and more often than not improve them after they learn how a particular mold behaves in practice.

Sand casting (the preferred method for low quantity bronze and cast iron runs) is error prone even in the best of cases but in the end it is very much worth it. Lost foam is another process that can work well for for instance aluminum (and is comparatively easy).

One reason why you really might want to stay from all of this is simply because it is far more dangerous than you might think when looking at the gear. But if you do go for it I would suggest starting with very simple castings and then to cut them open afterwards to check them for integrity and to learn what causes issues and how to avoid them. All the magic and the hard bits are in the prep work, the pouring is the easy part.

Forgive my ignorance, but what is there that's not machinable shape-wise, but is still castable? The more difficult the shape, certainly, the more difficult the casting?

Am I missing something?

You're not necessarily missing anything if you haven't done a lot of machining. But if you have then you probably know what I'm getting at. Tooling requires space to work, far more space than is sometimes available in the workpiece. So complex shapes, especially shapes with a lot of interior work and lots of detailing on all sides of the workpiece are much easier to make as a casting than as a milled or turned piece.

Every time you take a piece off the machine you need to re-register it, perfectly. This is doable but requires a ton of work and can severely constrain your design, after all, you'll have to re-clamp it after changing orientation.

You can easily see this by looking at for instance the output of 3D printers and then to try to think about how you would go about making the exact same pieces using substractive processes. Plenty of times you'll find that this is super hard or even that it can not be done at all.

Of course, the reverse is also true: there are pieces that you can mill and turn but that you can't make using an additive process. For every workpiece there is an optimum set of tools and processes to make it, some workpieces have a lot of options and some have only one.

When the number of solutions is 'zero' or when you have only some tools available and no access to others you have to get creative, maybe split the piece up, use a different material or come up with your own tools or processes.

> what is there that's not machinable shape-wise, but is still castable

Yes. For example imagine a 3d jewellery made of a web of thin filaments. It can be non-machinable for two reasons: The wires can be too thin individually and machining them out of a solid block would break them, while they can support themselves once cast. Or you might have shapes where one of the wires is surrounded by the other wires and you can't get the tool in.

As an example image: https://static.wixstatic.com/media/4f7223_21af8794dc874622a6...

Thank you for the example. It's clearer now. Still, I am puzzled at how you even go about making a mold for that.

Traditionally, hand carve the ring out of wax and use a lost wax casting method. These days you can 3D print in a wax filament or machine the wax in multiple pieces, hand finish, then cast.

The lathe is honestly one of the most underrated inventions of modern civilization.

Though I can't recall of the top of my head, there are certainly more than a few inventions which were simply not practical to build before the invention of the lathe because the tolerances were not good enough with traditional techniques.

There's an entire books series on this concept, the "Gingery" books where the first in the series is setting up a foundry for casting, while the second is making a lathe from investment castings because a lathe is the only tool in a workshop which can duplicate itself.

https://gingerybookstore.com/

the balance of the books are making the other tools in a machine shop.

Had the second book once upon a time, and will eventually get the entire set.

The practical kind of steam engine that drove the industrial revolution is one example. Steam engines existed earlier but when they started turning the cylinders, they became much more efficient which allowed them to be used for a much larger variety of tasks.

"The Perfectionists" by Simon Winchester goes into a whole lot of detail about the history of precision and the role it's taken.

Also Machine Thinking's videos "The 1751 Machine that Made Everything" (https://www.youtube.com/watch?v=djB9oK6pkbA), "Origins of Precision" (https://www.youtube.com/watch?v=gNRnrn5DE58) and some others on his channel.

There's an argument to be made that the rapid advancement of human technology is down to the creation of the metal lathe: https://www.youtube.com/watch?v=djB9oK6pkbA&t=751s

It sounds like you may have gone into casting with light info and unrealistic expectations for the process? Precision parts are always cast in a multi-step process wherein blanks are produced via the casting process and then surface prep and machining is applied as needed.

This post helps calibrate the expectations of those who follow. That's a good thing. It's one thing to know that something is possible, it's another to know the grade of the learning curve.

But casting is also fun and exciting. Mark of a good hobby, the waste of time also protects you from getting caught up in monetization.

> In my (admittedly limited) experience metal casting is a waste of time

Don't you mean pastime?

> It never goes right. It always has porosity. It very rarely even fills the entire mould.

It sounds like a few sets of skills that need to be mastered.

Metal casting is relatively safer and far more scalable than machining. Not to mention, who's going to be paying for all the worn lathes?

eh. I just bought a new mill because of space, but otherwise all my machine tools are from the 60s. yes, the ways are a bit worn. yes the cross-slide and table have a divots. yes, I had to pay too much for a screw because my lathe was broken and I couldn't make a new screw for it.

but they are much better made and with a little tlc are very serviceable machines. and they run less than $1/lb in the US because we shut most of that down.

Porosity can be reduced by using the correct flux.

YouTube videos about metalworking are how I learned there are several degrees of burn worse than 3rd degree. I’ll spare you the gorey details, but molten metal is not something to fuck around with on a whim. You’re basically lion taming as a hobby. Disrespect the “cat” and it’ll eat your liver.

I might some day try forging, but I’ll leave casting to the experts.

I started forging, knives for the time being, a while ago. Once I graduate to swords, I already have some parts I want cast in bronze. Which is, apparantly, easier to do than metal casting. In the speed I work on this stuff so, ask me again in 5-10 years whether or not it is actually true...

Tip for future you: start with aluminum, it's much more approachable. Just make sure your feed stock is a castable alloy, stuff like t6 or cans will make terrible castings. Easiest way to do this is to use chunks of scrap that you know were cast, so look for signs that the original part was cast like mold lines or unmachined surfaces.

The reason to start with aluminum is the temp is way lower so it's much easier to build the furnace and the metal is cheap and readily available. You aren't wasting your time, since all the basics of mold design still apply such as controlling shrinkage and preventing freeze off. Paul's garage on YouTube has some excellent videos that cover the process in an instructional way, many of the other channels that cover casting just focus on the finished project. While very cool, these videos aren't always super helpful for a beginner. People also hate on the gingery books, but there is a wealth of super useful information there and the fundamentals haven't changed.

It's a super fun hobby, especially if you're already into blacksmithing. But do be careful and definitely heed the safety warnings, there is definitely the potential for an explosion or very harmful fumes.

Thanks for the tip with aluminium, I'll keep that in mind. Once I get to it so, I'm already 8 months late on my son's kukri... Lucky for me so, the maker space I forge at, sometimes, has a blacksmith that drops by. So if I need help, there is a pro available!

Bronze casting is metal casting.

Hah, there I read metal as iron/steel in my head... it surely is hot round here...

If I may suggest: if you want to get into this stuff start off with lost foam (xps for best results) casts in Aluminum. It's probably the simplest process (after casting lead...) and it will at least give you an idea of the basics before more complicated moves.

> YouTube videos about metalworking are how I learned there are several degrees of burn worse than 3rd degree.

Isn't 4th degree the last stop?

https://www.urmc.rochester.edu/encyclopedia/content.aspx?Con...

After burning through muscle and bone, there is not much beyond that to warrant another level in the classification.

In fact, some classifications just end in 3rd degree, and bundle muscle and bone damage in it.

I'm not sure why you'd classify everything up to destroying the skin as 1-3 and then label 4 as destroying bone.

This one goes to six: https://nigms.nih.gov/education/fact-sheets/Pages/burns.aspx

> I'm not sure why you'd classify everything up to destroying the skin as 1-3 and then label 4 as destroying bone.

I'd wager that from a medical standpoint there is no functional difference between burning through fat layer, or going even deeper and hitting muscle and/or bone.

And yet the NIH says six.

>After burning through muscle and bone,

After bone its muscle and skin as it comes out the other side.

Metal spits and sticks to flesh, it's nasty.

Metal poured into anything with latent moisture (damp ingot tray, etc) is a steam powered mini bomb with molten shrapnel.

Glass working, hot or cold, is much better for your mental health, it doesn't spit or stick.

The steam bomb scenario is the most alarming scenario to me.

Though I’ve seen people destroy their garage floor as well.

Nah, the scariest is that aluminum, like other alkali metals, literally explodes when it comes into contact with water. This is extremely rare with aluminum since aluminum quickly forms a layer of oxide, and even when casting it's unlikely to happen, at least in hobbyist foundries. You can even find videos of idiots pouring molten aluminum into a swimming pool to show that it's "safe" and nothing bad happens. But the possibility is very real, and while it's pretty dang unlikely there's no good reason to intentionally pour your molten aluminum anywhere near water.

Edit: found a Hackaday article that covers this in more detail

https://hackaday.com/2020/12/30/water-and-molten-aluminium-i...

Aluminum makes it worse but steam explosions as such are nothing to sneeze at. And there are quite a few ways to inadvertently set you up for one.

Yep.

A classic video of the most common lab mishap with molten metals gets discussed to death here:

https://www.youtube.com/watch?v=KQjud8VCTYc

It's rare to find anyone who's ever done home casting that hasn't had a similar near miss at least once in their early days.

It's funny to look at .. but all it take to escalate is for molten drops to land on bare skin or flammable rags.

Must watch video for anybody thinking of doing metal casting.

I came this close to setting my garage on fire, some old rags were stored in a box quite a ways off where I was welding something and a tiny bead of molten metal somehow made it in there and set the whole thing off. What still gets me is how fast it happened, and that I wasn't initially aware of what was happening because the fire wasn't emitting enough light to make it through my protective goggles (auto darkening...).

Lots of lessons learned that day, all is well that ends well but I'd rather not repeat that.

They really softballed the chastising in this video. Dirty bench full of other objects, including a beaker of... something? If the aluminum had landed somewhere else we could have had a bunch of other stuff going on here.

Also if you're going to bother to have a partner in such a situation, they should be touching safety equipment while you're pouring. I bet these guys don't even know where the fire extinguisher is.

Yes, there is more wrong than right what that whole setup.

Casting on a bench top to begin with isn't the brightest idea, you place your mold in the center of a concrete floor and you cast with something long enough to keep you safe, and you wear heat resistant aprons instead of lab coats. They got off very light, fortunately. I hope that they also realize they're out of their depth in the education department, because by showing this stuff to others when it does work they are passing on a ton of bad practices.

The same goes for a lot of videos and articles about home made batteries. I think I spent more time and effort on safety while doing my battery build than I did on the actual building and I'm pretty sure that if I had not that I would have had a real problem.

But casting metal and welding are still far safer than working on large Lithium-Ion packs in my opinion.

If you can do it with some remote controlled contraption and wait 24h until everything cools off before entering?

I made a flowerpot furnace many years ago. I think maybe this site was the guide. It worked really well. I started off with sand casting and then used the lost wax method. I cast things like Lego men or chess pieces. I cast a variety of metals, lead (horrible, don't do that), aluminium, copper and this weird aluminium/magnesium mix I obtained from a burnt out car engine block.

For the crucible and various components for the furnace I'd make items out of fireclay and fire them first.

The blower for the furnace was a vacuum cleaner with a copper pipe attached to the vent.

It was a fun project though took quite a bit of time to get the metal up to temperature.

My wife fell in love with metal sculpting years ago, thanks to the local college offerings. Each of her courses exposed her to various approaches, such as welding and bronze casting. Her favorite by far was the once-a-semester iron pour.

There are 4 classes total, and you're allowed to take each class a maximum 2 times. So she maxed herself out because she couldn't get enough.

There was a road trip one year to another state, a gathering of like minds. It was held at a decommissioned iron foundry / museum. Various people gave talks on their style and techniques, which was super interesting according to my wife. She and the other students (and the instructor) had also brought along the molds they'd been working diligently on (wax filled) so that they could enjoy doing their iron pour onsite. My wife's project was 72 lbs once completed.

She said that between the weather (hot and humid), the locale, and the protective gear, she spent a lot of time uncomfortably hot and gritty. And loved every moment. It's her happy place.

She almost went with a group to Germany to do something similar; a metal sculpting retreat for a week or so. But the pandemic threw a spanner into that.

idk where you live, but there are metal artists all over..usually closer than going to another state. they will often work in groups where the space is cheap casting bronze doesn't require much beyond a little propane furnace.

if it makes her happy, she should really consider just starting and not waiting for arranged opportunities.

Are you in the US? I would love to host a metalcasting group here on my farm, as well as other fun activities like auto repair, lumber milling, and more. However, the potential liability involved with any of those groups has been more than enough to put me off the idea.

I have got a working metalcasting foundry in my shop that I would love to share, but the US status quo terrifies me. I do not believe that any amount of insurance would protect me fully in the event something should go horribly wrong. If something landed in court, enforcing even the most ironclad waiver or contract would be a huge and expensive gamble.

More power to those willing to burden the risk of losing their home and savings. It is an abject tragedy that this is the way things have gone.

I am. and sadly I did just lose a big chunk of savings because of metalwork-related litigation.

that doesn't mean I'm going to stop living my life.

What did you cast with the aluminium/magnesium mix? Was the origin of the mix an old VW Beetle engine?

More lego men. I didn't take much of the engine block. The car had been abandoned and burnt out and the engine had melted and pooled over the road. I don't remember the make. I took pieces that I could scrape up easily. I'm only guessing at magnesium because of the way it reacted when prodded. It would sort of pop and spit when I poked it when molten. I'd be happy to be corrected if someone knew of another metal that would react so violently when exposed to air.

That must have been fun

Whilst casting isnt for me... this website definitely is. One helluva error page too... "END OF THE INTERNET"

http://www.backyardmetalcasting.com/error.html

Having trouble detecting if the bits are random or encoding something. Ignoring the spaces and encoding to ASCII yields gibberish, maybe something else?

For those interested, a fairly comprehensive book on backyard metalcasting from scrap (from the ground up) is David Gingery's Build Your Own Metal Working Shop from Scrap https://www.thriftbooks.com/w/build-your-own-metal-working-s...

Starting with green sand, scrap metal, charcoal, and a pot, pour parts to build a lathe, and so on.

It looks like he has put out quite a few "how to" books: https://www.thriftbooks.com/a/david-j-gingery/381968/

This is probably a stretch but: if anyone knows how to contact the site owner Lionel Oliver, I know many old-school hobbyist metal casters who would really love it if he brought back the sister-site forums at alloyavenue.com. Thanks!

Try https://www.iforgeiron.com/

Thank you! I’ve been told however that members of the iforgeiron community routinely redirect casting questions to alloyavenue despite the latter having been largely unusable for awhile now

At the bottom of the page:

ironwords@hotmail.com

Does that work for you?

Thanks! Unfortunately I’ve heard that Lio has been unresponsive at that email address for several years

That sucks, makes you wonder if he's ok.

I love the lathe project [1], I recall looking at it quite seriously when I was younger. Inspired by this site, I welded up a crucible and setup to cast aluminum using charcoal in the bottom half of an old pot belly stove, with a hand dryer reused as a blower for heat. I did manage to melt some scrap, but I didn't have a mold ready that time. My diy flasks weren't great, and I lost interest while trying to get some green sand. I would like to try again though

[1]: https://www.backyardmetalcasting.com/lathe1.html

I had the first book of the Gingery set, but as I was rapidly moving around during college I never acted on it. The proposed workshop bootstrapping really made my imagination run...

Not related to metals: how cool is this website? Back in the day when the internet had no bs and it was just pure HTML

For anyone looking for an awesome series of books, these will expand your backyard workshop. Build Your Own Metal Working Shop From Scrap: https://www.gingerybookstore.com/

You start with learning how to cast, then work on casting parts for a lathe and other projects.

edit: It looks like the site's author has some of these books! He has a page detailing building the lathe: https://www.backyardmetalcasting.com/lathe1.html

Love the 300-pixel-wide images.

Actually, I hate them. I remember for the longest time people clung to small images on the Web. Sites would add "Zoom" buttons but when you clicked on them the images were enlarged maybe 50%? What was the point?

Sites like this were what made the early web awesome though. I confess though that someone's passion site like this though is probably better replaced now with the dozens of YouTube videos you will find on the subject. Video definitely killed the JPEG star when it comes to how-to.

Have you forgotten how slow 56k dial-up was? A high-quality 1MP JPEG would take the best part of a minute to load under ideal conditions. Firefox lets you simulate this in the responsive design mode. You can view the website at a resolution of the day (like 1025x768) and throttle the speed to GPRS, which is similar to 56k speed. You can easily see why they used small images. Having the larger images available was just them being nice, but it wasn't at all practical to have them by default.

Amazing to think that today we expect videos to start playing instantly.

The other thing is that at 1024x768 a 300px image isn't actually that small. On a 16" screen it would have been something like 5" diagonally.

Watching images load in line by line at a torturously slow pace over dialup may have helped me build such zen-like patience.

....or explain my appreciation for delayed gratification. Didn't even know I was developing that as a teenager.

Gosh I spent a lot of time contemplating a sojourn into backyard metalcasting. Building my own lathe was a longtime dream.

This type of website is where I spent the late 90’s. Tesla coils and quarter crusher instructions. This is a great website!

This website set me off on my current path in about 2005ish.

What is your current path? (Besides it being a detour...)

The simple explanation is the belief that (generally) High-end appliances charge too much money for too little thought. The use of material is inefficient and the supply chain could be better.

I'm trying to make (ambition dates to 1990) a computing platform with a 100 year view of usage. The idea is that actual human usable technology can be quite slow becuase the human time scale is long. The churn of current technology is actual vestigial growth.

As soon as I could I registered cogs.com under the belief that in the future we will only understand technology metaphor.

Flash forward 30 years and I have finally established a small run manufacturing facility in an old school. I converted the 7 classrooms into studio apartments to facilitate my design ideas. The idea is rent the apartments for income and develop appliances with my CNC in the 60' x 30' gym/cafeteria/auditorium.

Backyard Metalcasting set me off on building:

wooden CNC with gecko drives from that guy who built the prototype kit in the bathroom with his wife yelling at him in processed unintelligible language with kids crying...

The idea was that I can use it to make molds.

Initial I was going to make appliances in batches of 10 and either stock what didn't sell or make more of what did. The idea of 10 is that technically I'm an industrial designer BSID 91 UArts. No industry no industrial design and I reasoned that by creating 10 of something it was proof of industry as opposed to art.

I got a legitimate CNC for my studio behind my house and with 15 minutes of installation realized I needed to move it to a legitimate location.

Found a school for sale a mile from my house house and decided to flip the script. I would simply make appliances in the gym and use the rental income instead of worrying about all the sales work. 7 was close to 10 and maybe I could get 3 walk sales.

A short 5 years later the school is finally producing income with 2 studios rented one more and I'm either breaking even or a little ahead on an annual basis. I currently break even most months. (tax bills and insurance).

I'm actually at the point where I can truly get started and I have been finalizing my technology stack. I plan to develop a sloppy in-efficient prototype version that considers the entire building as this 100 year computer and the HVAC/Power/cleaning/snow removal will all be managed by this computer. The belief is that the magic of the computers is in the integration of human need and simple experiences. There will also be a parallel track of development for a streamlined ultra efficient implementation of the same model.

The reasoning between developing along those 2 tracks is that with the building I can focus on the human experience practicalities be damned. The refined version with be resolved experiences in the smallest form possible.

Here is my studio.

https://www.icloud.com/sharedalbum/#B0YJEsNWnJEa0eN

Here is the rental site with outdated photos but some pictures.

view.cogs.com

Shameless plug studio 4 and Studio 1 are currently available. The rent includes fiber connection and we can talk about a static IP if needed.

Finally for the doomscrollers out there I have 4000 photos of the whole project here.

Anyone can view this shared album at: https://www.icloud.com/sharedalbum/#B0Y5oqs3qnakFd

HN provides a great survey of old and new technology trends with no ads. I find it is like shouting into the wind and marvel that the site works.

I feel my path has been very consistent and filled with obstacles. I'm aware that I'm my own biggest obstacle.

This is absolutely fantastic. It's a pity you're on the other side of the Atlantic or I'd be more than happy to become one of your tenants.

You may want to put a fresh certificate on cogs.com, the current one gives an error.

Really, really love this, thank you for answering in such detail.

Should be no certificates for cogs. I”m about to go through a revamp. I do short term rentals.

Thanks for the feedback.

I need the practice describing what I”m doing.

I just 'doomscrolled' through a few hundred of your pictures, incredible what you've done with that building, that must have been a pretty costly undertaking. I've done some work like that but on much smaller buildings and it gives me a bit more perspective on the magnitude of what you're doing and what you've accomplished already in a relatively short time. Best of luck with this whole project, I really wished I still lived in .ca.

Thank you, it was 40% beyond may capabilities. This was a real challenge and I barely made it. I feel like I did a lot prep work and I'm at the start line.

I can't stress how nice it is to hear a complete stranger see my efforts as progress. I'm truly going for it and it is scary. I constantly think that all I'm doing is placing new obstacle in path and lying to myself about being focused.

I had a healthy cash pile that I was saving for my runway and now I have building.

> I had a healthy cash pile that I was saving for my runway and now I have building.

I have a similar tendency to get caught up in side shows, but assuming the real estate market is reasonably healthy where you are once the building is done it is an asset that you could liquidate if you wanted and that should net you more than what you put into it.

But if the market is not healthy then liquidation is not an option but you can turn it into an income generating asset. The hard part will be to rent it out to people that want to have living space whilst still having access to part of it as a workshop, such a mix tends to be quite bad (I lived like that for a couple of years but would not recommend it to others, unless your work is your life it's going to be frustrating).

Regardless of the outcome: you have created something that is absolutely off the scale for a single individual, and that's something to be proud of, your stamina and ability to stay focus during all of that time is proof that you are capable of incredible feats and the experience will serve you for decades to come in whatever enterprise you care to attach your name to. Your biggest challenge will be to choose between several options, (1) cash out, then continue to chase your dream, (2) become a landlord and use the surplus to live off and regroup (assuming the maintenance of the building doesn't eat up your time) and (3) find like minded individuals and treat the building as a shared resource (so allow them to buy in to liquidate some but not all of your capital and end up with shared responsibilities and labor). If it works 3 would be lots of fun, but it will require very careful selection of the parties that you allow to buy in. 2 will be less fun, especially if the building still eats a lot of your time but it may turn into a stable source of income. 1 would allow for a clean break at a (hopefully) slightly higher level than where you were several years ago, and with extra cash and more experience your chances of success for your other project have gone up.

There may be other options as well that I haven't thought of, and given that I don't know anything about the location where you reside (which is the main factor in real estate pricing) it may be a case of throwing good money after bad. But the experience is yours, regardless of the outcome and that is an investment in yourself. Those will pay off, even if not immediately.

Much, much good luck with all this, if you want to use me as a soundboard you're more than welcome to email me (mail in profile).

This is very interesting.

I have looked into getting a garage CNC, what did you realize after the home install that you needed a legitimate location? The size and sound of it?

Many reasons. I tend to overdue things so I spec’s pneumatic devices that required a large 10 bar compressor. I installed that in the basement and managed to muffle the sound with rockwool. I ordered a German machine which was to sensitive for a VFD so I used a motor-gen set which shook the 1879 New England farmhouse.

The space for the CNC had low ceilings and it was cramped. I could have lived with it but considering the other issues I moved.

I thought the move would be fast no way would it take more than 2 years. The money I was saving for runway is now an 8 unit apartment building but I have time and space.

this is awesome and seems like a great resource; i'll personally stick to backyard welding (no pun intended)

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