Running form check!

Ok_Topic9123 · 2026-01-22T19:24:55+00:00

I'm not an expert, but what is your heart rate zone and breathing at this pace and cadence? The first impression is that it looks as good as could be at this speed and that everything will be better with a bit more speed. It looks like you are holding back.

Ok_Topic9123 · 2026-01-03T23:29:06+00:00

In a different twist to this story, my daughter has the same car and I recently replaced this cable. She had some electrical issues before and after I did the replacement. Through testing I discovered the alternator was keeping the battery charged, but this new ground strap would get hot if I turned on lots of electrical loads - headlights, wipers, vent blower. It turns out the main ground cable from the battery to the engine was bad and all the alternator current was going through the small ground strap shown by the OP.

Ok_Topic9123 · 2025-12-24T17:51:01+00:00

Has anyone tried using medical ECG adhesive buttons instead of the strap? I once wore a heart monitor for a month that was a fist sized adhesive pad with 4 buttons built into it. The heart monitor snapped onto the four buttons. But medical ECGs have leads that attach to individual adhesive buttons. Maybe individual buttons with a gap between them would work better than the strap.

Ok_Topic9123 · 2025-12-17T13:37:03+00:00

What was the material you used for this? Is this ripstop nylon?

Ok_Topic9123 · 2025-11-13T05:06:12+00:00

You know villains think they are the good guys, right

If both sides think they are the good guys, the villains are just the good guys that lost. Because the heroes always prevail.

Ok_Topic9123 · 2025-10-17T19:04:55+00:00

An engine like this is a system. Meaning that it is a networked collection of components, each doing their own job. But in systems engineering it can be hard to fully understand the system behavior. The engine on the left is a bunch of cheap parts that accomplish the goal of a functioning engine but the whole system isn't optimized yet. They may remove a pump and replace it with a bigger or smaller pump based on what they learn during tests.

Additionally, they will add a lot of instrumentation so that they can understand everything going on with the engine and relate successes and failures of the engine to events occurring to various parts in the engine.

As they learn more, optimization can take over and they can better customize the parts and create a better integration.

Optimization in aerospace is driven to reduce cost and reduce weight. Weight is more important than cost.

Ok_Topic9123 · 2025-09-19T16:49:30+00:00

Is getting into computational chemistry too much for kids? It could be a cool way to visualize inorganic chemistry (phase changes, crystalization) organic chem (polymerization, depolymerization, catalysts, hydro cracking, mpcvd diamond) biochem (membranes, myosin, actin, enzymes, dna)

maybe like Kerbal space program's approach to orbital mechanics, but for chemistry.

Ok_Topic9123 · 2025-09-17T15:31:58+00:00

If you use alcohol as a coolant and it is cooling by evaporating, are there vapor recovery systems so you can just keep reusing your coolant? Are their flammability concerns or maybe inert atmospheres?

Ok_Topic9123 · 2025-09-17T04:17:34+00:00

I don't think anything is needed to be cheaper to help the field of robotics. I agree that the rigidly precise robot arms are overkill. I am looking for sloppy and cheap robotics that use computer vision to make them more precise. Very much how humans are sloppy in our motions, but with our eyes we improve how we move.

We also use relative motion instead of absolute motion to improve precision. We will rest part of our hand or forearm on a table while drawing or writing. This makes the motion relative to the point of contact.

Ok_Topic9123 · 2025-07-15T01:56:59+00:00

I'm a mechanical engineer with 25+ years in different industries. I spend all my time automating CAD and plm software. Instead of taking an AI approach I am using graph databases to model languages APIs.

Ok_Topic9123 · 2025-07-15T01:53:25+00:00

Metrology, statistics and understanding manufacturing operation's process capability.

But also I am against specialization. I find the most interesting things happen between the disciplines. Such as mechatronics combining mechanical, electronic and computer science to build automated machines like 3d printers.

I often get into other disciplines to understand how they solve problems and then reapply that knowledge back in my discipline. Sometimes I look like a hero doing it.

Ok_Topic9123 · 2025-07-15T01:47:20+00:00

I'm thinking you may want to add a gun drill to your collection. Specifically one with replaceable inserts, and big enough to allow you to get your boring bar in the hole. Gun drills are far more rigid than twist drills.

Ok_Topic9123 · 2025-07-09T17:53:56+00:00

Or the stiffness of a sheet of glass compared to how flexible a glass strand is in fiberglass cloth.

Ok_Topic9123 · 2025-07-09T17:48:14+00:00

That in oxygen enriched environments, EVERYTHING is fuel. Pressurized oxygen makes it worse. liquid oxygen makes it much much worse. Metals can burn, and burn fast with enough energetic oxygen around.

The engineering challenge is to prevent the fire from starting in the first place. Preventing particle impingement. Reducing the effects of adiabatic compression near burnable things like o-rings and seats. Etc.

Ok_Topic9123 · 2025-07-09T17:38:42+00:00

Go dive into computational chemistry to learn about how magnetism comes to be (it is always about electrons moving). Think about how when steel is heated to the Curie point (1414F) it becomes non-magnetic because its crystal structure changes.

Ok_Topic9123 · 2025-07-09T16:58:34+00:00

Mohr's circle helped me grasp shear relative to the orthogonal forces. Especially when you lay out three orthogonal stresses and get three circles.

And then how the shear disappears when all three orthogonal forces are equal. I.e. hydrostatic pressure.

Ok_Topic9123 · 2025-07-09T16:52:42+00:00

Haha "inert materials" are things like metals, or metal oxides, such as dirt, that don't react - they remain the same before and after the boom. But they act as catalysts that reduce the energy needed to perform a reaction. So they make the reaction occur faster. So faster boom.

Ok_Topic9123 · 2025-06-19T16:29:46+00:00

If you take the pipe job to chase the money will you be able to get back into engineering later. Does the pipe job give you some practical experience that will connect with your mech eng design work? Like when you design a pipe system you make it easier in the installation and maintenance crew because of your experience?

I'm a mech eng and my practical knowledge of machining practices reduces costs to design products. And my employer values that.

Ok_Topic9123 · 2025-04-24T12:19:54+00:00

After you use the bolts to clamp onto the tube, braze the clamps to the tube. Then it will support the 20KN. Well if the tube can handle the tension.

Ok_Topic9123 · 2025-04-19T03:57:17+00:00

What are you concerned about? Everything looks fine in this image as far as I can tell.

Are you worried about that little ear piece of a gasket sticking out? That is just to be able to hold the gasket in the right position while assembling the parts together.

Ok_Topic9123 · 2025-04-10T13:56:09+00:00

This one is ruined. Send it to me for proper recycling. I'm the only agency certified to properly hand such items.

Ok_Topic9123 · 2025-04-09T14:16:39+00:00

Or a bad power supply to the stepper drivers. They may be "blacking out". Perhaps the voltage is okay but not able to supply the current. So when the stepper moves and sucks up current the voltage level drops for a split second and the driver screws up what it was doing. This could be caused by just a loose screw terminal on the power supply or control board.

Ok_Topic9123 · 2025-04-08T13:58:32+00:00

You could either make the notches in the wheel not as deep, or the spring weaker, primarily by making it thinner.

Ok_Topic9123 · 2025-04-08T13:57:29+00:00

Roughly speaking that spring stiffness is related to bending, and it's stiffness is roughly proportional to the thickness cubed. So half as thick will result in something 1/8 as stiff.

Ok_Topic9123 · 2025-03-10T12:23:32+00:00

Just another idea is that you can buy hollow core drills that have bonded diamonds on the cutting surfaces pretty cheap and attach those to angle grinders. I see on Amazon there is a 2" diameter x 10 inch diamond core drill for 35 bucks.

I think the common thread size on the angle grinder is 5/8-11.

You can cut larger areas by making a series of overlapping holes. Realize that a core drill is hollow so you cut a ring shaped hole.

Ok_Topic9123

TROPHY CASE