Never designed around random gears before and it took a lot of iterations before they’d mesh and turn smoothly.

front wheel hub of my jag, diameter is about 35mm

I wanna bust some rocks. Maybe build a cave. It doesn't matter, the journey is the goal. Zen and all that. I've got a 10 feet tall granite face and I wanna make it my bitch. Maybe it turns into a cave, maybe it doesn't.

So far I've been using brute force, drilling, hammering, feather and wedge, jackhammering... It's all good. But I haven't done explosives yet.

Before you get your panties in a bunch, I'm a (mostly) reaponsible adult, I'm an engineer and I'm a hobby chemist leaning towards the fun side... I'm not completely clueless and I'm aware about the dangers. Also, the scale here is the absolute smallest scale. Like splitting those 50+ kg boulders.

But I was thinking about deflagration vs detonation. Most rock cracking seems to be done with rather slow burning stuff. That seems odd to me, and I wanna understand it better. To me it would seem that a deflagration is more dangerous than a detonation. A deflagration would require more energy to deliver the same shock to the rock, and seems more likely to propel shrapnel with its "slowly" building pressure. Wouldn't the instant shock of a high explosive detonation be much safer?

Another reason I'm leaning towards a high explosive is the ease of setting it off. I saw a video of a guy using some sort of cartridge, I think it was some sort of blank round for a gun. He then just shoved it into the hole and followed it with a heavy chisel/rod. Whack it, cartridge goes off, rock cracks. I tried this with nitrocellulose, but it was a bit underwhelming. I got more of pfwup and no crack.

So I was thinking I'd do the same but with nitroglycerine instead. Very high explosive. Yes, I've synthesized and also used it before, and again, yes I'm conscious of the dangers. But this is the point where I'd like to have some more meat on my bones knowledge wise. How does rock cracking with low explosives vs high explosives differ?

For cleanup work at the Key Bridge collapse

I’m getting a cheap chinese 24V DC air conditioner, and I would like to measure the actual cooling capacity in order to compare the efficiency to other AC units.

Ideas? My first thought is to submerge the evaporator in a barrel of water and measure temperature change.

The first three threads the nut engages with are fully intact. Only a small portion of the last two are missing. Worried about the nut potentially failing.

Have always seen people use welding masks/goggles to view solar eclipses, anyone switch it up and weld while wearing these now almost useless glasses?

Unavailable for purchase anymore considering the company that made them is no longer around.

I need help please, I don't what kind of model is it

Seeing if anyone has good resources for how rotophase work and or diagnostics. Work for agriculture irrigation service company work with many rotophase and vfds. Have one brand of rotophase from a local shop that we have lots of problems with starting issues. These rotophases are usually in a remote location and operated remotely via phone app. Most problems we show up to looks like start board failure with multiple start caps blown. Replace parts and motor still won’t start. Long story short, after searching blogs I found we may have bad rotor. The person who started the building the rotophases has passed away and the new owners seem to either not know ornot be willing to give info on their rotophases. My concern is we are getting calls because the shop in question isn’t servicing these rotophases timely. I feel like I have a good basic understanding of how a rotophase works as far as checking motor windings, start boards and capacitors. Just trying to dig deeper and find out as much as I can about the whole theory of rotophases. Looking for any input or good resources for information, really anything that can save some time on figuring out what’s going to with these things. If it matters the motor they are using is a weg frame size 324t. Sometimes in parallel with another and sometimes just a single.

Not sure this is the right place for this question. Just found rotophases have been talked about on here before. Thanks!

I found this behemoth sitting in a junk pile at my neighbors, he said I can take it and fiddle around with it, does anyone know anything about these? It's gotta be at least 60 years old and I only found a single Forum online about any Jay-Diamond jackhammers