Welding Spots

Continuing with the theme of sheet metal tools, I decided to add a spot welder to my arsenal.

Admittedly the motivation here is partly "they're really cheap" but I also have a project coming up where being able to weld together pieces of sheet metal will be preferable to riveting them in some spots. But more on that in a later blog post, for now let's get this thing out of the box and test it out.

Yup, looks like a spot welder. Interestingly the instructions seem to imply that the time required for a weld is at least partially dependent on operator skill, which is an interesting take.

Since this is a 240v welder they apparently decided that there's too many different options for 240v plugs so they just ship it without one. So, $20 added to the final price to make up for that, I guess.

Well no worries, on it goes.

Now I can just plug it into the 240v outlet in my car hole which is right over... wait a minute.

Just kidding, I actually did this on purpose. My TIG welder also uses a 6-50p, and I have an adapter that goes to 10-30p.

I could have bought the 10-30p plug for this, but I eventually want to put in a proper 50a 6-50r receptacle, so swapping the plug end out again later would just end up being a waste.

Of course this spot welder only requires 16a so all of this is overkill, but it's much more convenient than trying to figure out how to power a 120v spot welder since most of those require a 40a 120v circuit, and who even has those?

Anyway, time to stick some metal together, so we'll grab some scraps of 26ga galvanized.

Spot welding is really nice for galvanized since it doesn't boil off nearly as much of the zinc as other welding processes, so you don't have to strip off the plating or take extreme measures to avoid inhaling the fumes.

Alright, let's give this a zap.

Ok, that was too much zap, I left a little smudge of the electrodes in the weld. I guess on the bright side I didn't blow a hole straight through, so that's nice.

I think I got the timing worked out on the last weld. I really does only require just a tiny tickle on the switch to produce a solid weld on this gauge metal, despite the galvanization which can sometimes require a bit of extra energy to zap through.

And it is properly stuck together, I pried the sheets apart here and the metal just bent right at the weld nugget.

So that's another capability unlocked I guess!

Just A Little Nibble

So I have a project coming up where I need to fit something into a square hole. Getting the thing in the hole isn't the hard part, though, it's making the hole in the first place in a piece of sheet metal.

You see, if you want to make a small round hole, you can use a step drill bit. If you want to make a large square hole, you can use shears. But a small square hole? That requires a different approach.

I have chosen the approach of using a nibbler.

The way this works is, as its name might suggest, by nibbling its way through the metal, using this square edged punch thats drawn down into the face of the tool.

So let's give it a test run on a small piece of scrap, just a bit of 26ga galvanized left over from a previous project. The first step is to drill a 3/8" hole so that the die of the nibbler can fit through.

And yes, installing this toggle switch in a piece of sheet metal is the actual task I'll be aiming to do later. It requires a 1/2" by 3/4" rectangular hole, which I scribe out on some blue sharpie.

The scrap itself isn't perfectly square, so ignore that it looks a little wonky on the top edge.

Anyway, let's give it a nibble.

Well that was refreshingly easy. The nibbler went through it just like butter.

Also pro tip: if you've never used one of these before you might think that the tool should be inserted from the top, but it is way, way easier to guide the cut if you insert it from the bottom, so try to do that whenever possible.

After making a full lap, the hole is pretty close to the marks, but I did miss them here and there by just a smidge.

Rather than try to shave off the last little bits with the nibbler, I'll instead use some files to take the cut to the line. It'll also give me a chance to deburr the hole, which can be a little sharp on the backside.

And a test fit shows that the switch snaps right in.

And everything looks good from the back too.

Well, I'll call that a success.

Pure 90s Cringe

Since it was recently 3/03 day, which is one of the few "funny number" days that both Americans and Europeans can agree on, I decided to pick up a 303. Not the legendary Roland TB-303 bass synthesizer, the device which single-handedly launched the entire musical genre of Acid Drum and Bass, but instead the Roland MC-303 groove box which launched absolutely nothing of value.

Which is a bit odd, considering that this one box could easily substitute for a TB-303, while also stepping in for much loved drum machines like the TR-808, TR-909, TR-606 and CR-78, while still having room left over for 6 more (admittedly rompler) synth parts.

But its cardinal sin was, I think, that it came with too many preset patterns, which led people who consider themselves serious musicians to dismiss it, putting it in the same category as those home keyboards that play a whole song when you just hold down a single key. Thus it was relegated to the DJ table of tweeners' birthday parties where they could dance to its slightly too repetitive preset beats.

That said, many products that Roland has produced over the years, like the aforementioned bass and drum machines, were initially considered failures until they were unloaded in thrift shops and sold for $100 to a new generation of aspiring musicians who would then go on to produce great, genre-defining works with them.  The MC-303 is no different in that regard. Well, at least the part where I picked it up from a thrift shop for $100, I don't think anyone's made any great, genre-defining works with one. (Though the MC-505 that came out later as its replacement did see some success)

Anyway, all that aside this box was only $100 because it doesn't work, so let's crack it open and see what juicy goodness awaits us inside.

Ah yes, juicy goodness. Some obvious signs of spilled liquids on the bottom case there.

And it's on the main panel PCB as well, here's a few extra juicy spots.

And on the top side things are looking kinda sticky.

When I did the initial tests the unit powered on and most functions seemed to work, but the buttons in this corner in particular were largely nonfunctional, including SW27 which is the 'Play' button. Rather important one, that. Checking the resistance showed a reading of hundreds of ohms with the switch pressed, so they obviously need replacement.

So let's get the plastic key caps off and bust out the IPA.

And with a little scrubbing, things are looking dramatically cleaner.

This cleaning didn't bring the switches back to life, of course, and these rubber dome 8x8x5 switches in particular are a bit tricky to find replacements for.

The original switches are made by Panasonic, and Roland was very fond of using their switches for a while in the 90s up until Panasonic stopped manufacturing switches because they were so incredibly bad at it. Other manufacturers still make similar switches, but most of them are semi-anonymous Chinese factories that are hard to pin down the identity of and even harder to order from. Luckily there's still some new-old-stock of the QJJ05Q switches floating around, so I ordered some of those off eBay and we'll see how things go when they arrive.

The other tact switches are thankfully much easier to find, they're just bog standard 6x6x5 clicky switches with the only peculiarity being that they're 2-pin rather than the more common 4-pin variety. I already had a bag of them laying around that I was planning to use for my Roland JP-8000, but I didn't feel bad pilfering them as I can always buy more.

So, nothing to it but to do it.

35 old crusty switches come out...

And 35 shiny new switches go in.

Then everything goes back in the box, which has now been cleaned, for a quick test.

Don't worry about half the display being blank, that's just due to the really slow refresh rate on the LED matrix.

And with the knobs back on and the case buttoned up (and with the picture timed to show the other half of the display lit up)...

All the replaced buttons are working perfectly, and I was able to validate the full functionality of the system.

Quite surprisingly I didn't need to replace or service any of the potentiometers along the top. It's really common for them to get damaged since Roland for some reason didn't see fit to actually bolt them down to the solid metal front panel, so a suitably forceful sideways strike can basically split the potentiometer clean in half. I guess I'll count my blessings on that one.

Anyway, all that's left to do now is wait for the NOS switches to arrive so that the 3-4 dead keyboard keys can be revived and it'll be good as new. There'll be nothing left to fix or improve...

Or will there be? Stay tuned.

Spring Has Sprung

I may have mentioned this in a previous blog entry, or I may have not, but in either case I've been on a mission recently to rid my yard of calla lilies, or at least the ones that are popping up in inappropriate places, like in plant pots with other plants, or interspersed with my rosemary, or erupting out from under my iris plants.

But I decided to leave the ones here beside the former hantavirus shed.

There's nothing else growing here and they're basically out of the way, so they can stay.

Anyway, the plum is in full bloom now and looking all white and fluffy.

Hopefully I'll get a decent crop of fruit this year, but one never knows.

Elsewhere the geraniums are doing their gerenial things.

And the periwinkle are being their usual unkillable selves.

I've been debating ripping up this one too, as it's a rather aggressive invasive plant, but so far I've managed to keep it contained without too much effort.

The milkwort in the front is doing surprisingly well, despite it repeatedly trying to kill itself.

And the same goes for the spanish lavender.

The french lavender isn't in bloom yet, so we'll give it a few more months before taking some beauty pics of it.

The pink lemonade blueberry is in full bloom.

I'm not expecting a huge crop because the plant is still pretty small, but we'll see how things progress.

The gay goblin is being gay and goblinesque.

And the japanese boxwood is looking green and fluffy.

Though perhaps a bit too green and fluffy, so I gave it a quick trim with the hedge clippers after taking this photo.

All in all the yard is doing quite well so far this year.

The Freshening Part 5

So it's about time I got this project fully wrapped up, and a little ahead of schedule as I managed to get an early start today which meant I could burn some time before lunch, and thus before the attic turned into an inferno that would cook me alive as soon as I poked my head up above ceiling level.

Of course, the first task didn't even take place in the attic itself, but rather in my car hole, where I bent up a piece of sheet metal into a 5 inch round splice.

Fun fact: you can make round things on a sheet metal brake... Well, sort-of-round things. Round enough.

Anyway, that piece goes in between the too-short piece of duct I installed a few days ago and the new piece of duct that arrived on my doorstep.

So this area over here is no longer a hideous octopus of aluminum foil ducting.

And what did I do with the remaining 15-or-so feet of duct from the 25 foot box?

I shoved it back in the box. I'm sure I'll find a use for it at some point. It can live up here until then.

Speaking of boxes, I installed the relay box which allows me to adapt the 120v timer switches I installed last time to the 24v control lines that the HRV uses.

It's just a pair of relays with 120vac coils (which is apparently a thing) wired up exactly how you'd expect them to be.

And good news: even at full zoot with the "Taco Tuesday" button switched on, the HRV is still barely audible down in the occupied portion of the house. In fact, I think removing the duct-o-pus from the output actually made it a bit quieter than it was initially, which is pretty sweet.

So the only other question is: how efficient is this HRV? Well, it was a little over 28c outside the other day so I pointed my thermal camera at the fresh air vent.

Hmm. Well, I guess I can't really expect miracles when there's only 4 degrees difference between the inside and outside temperature. And, let's face it, this is California; the main goal here, which I achieved, was getting more air circulation inside the house without having to open the windows and let a bunch of pollen and pollution in.

But while I've got the thermal cam out, let's see how the insulation in the car hole is performing (which is still an ongoing project).

Well now that's a bit more of a dramatic difference. The face of the insulation (left) is only 25c while the underside of the roof (right) is roasting at 42c.

Now that the HRV project is done, I'll hopefully be able to wrap up the insulation project over the next few weeks before spring really kicks into high gear and the hot days become more inconveniently frequent.

But in the meantime I've got some fresh air to enjoy.