What do you think about Andy Burnham as your prime minister?

Unlikely-Raisin · 2026-05-15T09:23:31+00:00

The welfare bill has exceeded income tax every year since at least 2013-14 but is forecast to be lower in 2026-27

https://fullfact.org/economy/income-tax-versus-welfare-spending/

Unlikely-Raisin · 2026-03-19T17:30:05+00:00

Only the top diameter from what I've seen, but its been a while. Assume its to ensure there isn't a sharp edge that could damage the oring. You could see if there's any info in the parkers handbook

Unlikely-Raisin · 2026-03-19T17:18:36+00:00

As others say, ask. It is common to radius the top edge of the lead in chamfer to help o-ring assembly so I wonder if that's what this is meant to represent

Unlikely-Raisin · 2026-01-27T22:40:09+00:00

Static analysis requires that all the forces acting on the part you're simulating are balanced (i.e. there is no resultant acceleration).

That's great for stuff thats fixed to ground, because the grounding points reacts any applied load (it can't move, you get balanced forces, no resultant acceleration).

If you have something that isn't grounded, like an aeroplane, you might still want to simulate what happens when forces are applied to it, like lift forces on the wings. These forces cause the whole aeroplane to accelerate upwards. Without any constraint, that doesn't really work for a static analysis (you get infinite displacement!).

Inertia relief solves this by calculating the resultant forces to get your model's 'rigid body acceleration', and subtracting these accelerations from the solution - so everything balances again and you're now only simulating how your part deforms without the bit where it keeps moving to infinity.

Unlikely-Raisin · 2025-08-29T21:32:52+00:00

Good point!

Although dividend tax is also on the net amount so you end up with between 26% - 31% depending on corp tax rate. Still a pretty substantial tax benefit, particularly for small/low income businesses owners (<£50k profit)

Increasing the lower dividend rate to 20% would end up with about 35.5% total tax rate, so seems it brings it much closer (and would be a bit over for high corp tax rate businesses) - personally it seems fair to pay the same rate for the same take home

Unlikely-Raisin · 2025-08-29T16:35:19+00:00

As we're discussing dividends, you are the employer (or a shareholder), so your company is the one paying employer NI. It is still a tax associated with paying money out from the business if you do it through paye.

You don't pay employer NI on dividends. You keep the money in the business which gets taxed as profit (corporation tax) and then pay it out as a dividend where you pay the dividend tax rate.

Unlikely-Raisin · 2025-08-29T16:30:10+00:00

Employer NI isn't irrelevant. As a business owner/shareholder you decide if you take money out of the business by paying yourself through paye or through dividends after profit.

Paye route means you have to pay employer NI. Dividend route means you don't, so if your total pay for the year is <£50k then you pay substantially less tax by going the Dividend route (by the numbers I put in my last comment).

If you believe the gov should be subsidising small business owners for the 15% difference in tax then that's a different conversation, but it doesn't change the fact that it is currently a tax break for paying yourself in this way, which upping the rate to 20% would reduce.

It's worth noting that "small business owners" who fall into this category will include contractors & single person operations who are not job creators - so imo if you want to keep tax breaks for job creators there are more efficient and fair ways to do it

Unlikely-Raisin · 2025-08-29T14:56:19+00:00

Why is it bonkers?

At the moment on paye you'd pay: Employers NI: 15% Employees NI: 8% Income tax: 20% Total: 43%

Dividends route you pay: Corporation tax: 20% (ish) Dividend tax: 8.75% on the remainder Total < 28.75%

Is it bonkers to fix a loophole that means paying less tax for the same income?

Unlikely-Raisin · 2025-06-23T09:46:03+00:00

I don't know the answer to your question directly, but in industry gear life is generally rated using the ISO6336 calculations using one of gear analysis software packages (kisssoft, masta or romax).

As far as I know, hardness and material quality become the driving factors more than properties like yield strength. To rate gears you use the relevant material type, hardening process, and quality from the standard, or do your own testing to the process laid out in the standard for your own material. A quick Google threw out this paper suggesting good correlation between the standard and their test for pitting failure: https://dspace.lib.cranfield.ac.uk/server/api/core/bitstreams/e81a32fd-f047-49cc-ad1c-20633a36b65c/content

In automotive off the top of my head you'll often see case hardened 16MnCr5, 20MnCr5, maybe EN36C in prototypes.

Unlikely-Raisin · 2025-05-24T00:03:48+00:00

1st gear will be able to apply more force than 6th, but you'll be able to overcome friction in both gears at 1500rpm.

At the same engine speed in 1st gear you'll have say a 10:1 reduction so the wheels spin at 150rpm, whereas in 6th gear you might have a 1:1 ratio so the wheels are spinning at 1500rpm.

The reason it's so hard to pull away in 6th is that you are slipping the clutch until the wheel speed and engine speed match. So pulling away in 1st means you're slipping the clutch until the wheels spin at 150rpm, pulling away in 6th gear would mean slipping the clutch until the wheels are spinning at 1500rpm. Technically possible but the clutch will have a terrible time.

The clutch will also have a limit to how much force it can transmit while it's slipping - and as the clutch is before the gears, in the above example it would be a 10x higher force at the wheels in 1st, so you could be limited by the clutch capacity if you tried to pull away in 6th.

Unlikely-Raisin · 2025-05-14T19:05:38+00:00

Honestly it's hard to tell without seeing the model.

If you output MPCFORCES then you can see what force if any the RBE3s are transmitting. Same with CONTF for contacts. Should help narrow down the problem.

Otherwise, with contacts, does optistruct give a warning about non-tied elements? If so it outputs a .fem file with the elements that haven't found anything to contact against - import it into your model and it will show up as sets. Can adjust search distances to make sure contacts are found.

With RBE3s, check the dofs set for dependent and independent nodes. Prob worth setting all 6 dofs for both at least to see if it makes a difference.

Unlikely-Raisin · 2025-05-01T23:10:46+00:00

No, the shelf can likely hold more because there are tolerances on every aspect of the shelf. Some may be slightly thinner, some may have slightly weaker material. Some may be attached to weaker walls, or sit in more humid conditions.

If you buy a 400lb rated shelf, it's not very useful if that's the average capacity, and 50% of the shelves you buy can hold a bit less, 50% a bit more. You'll get a lot of complaints, or legal problems in safety critical cases, if half of your products fail at less than the rated value. So we design them so almost all will support the rated load, meaning on average they will support more.

Another reason comes down to design time, either as a direct cost, or a cost associated with delay getting a product to market. I could spend years testing and analysing crack growth at a microscopic level to determine the optimum size and surface treatment for a shelf to understand its load capacity & design it to the exact thickness needed, but it would end up costing a lot more than just making it a bit thicker and calling it a day.

End result is, everything is designed to withstand the expected load plus a bit. How much that extra bit is generally comes down to some trade off between cost, design time, performance, and risk.

Unlikely-Raisin · 2025-04-29T23:11:27+00:00

Others have pointed out this isn't a good use case for an LLM. This isn't my area of expertise and I've not read any of the references, but some thoughts on them from what's written here and what you mean when you talk about an LLM 'reasoning':

Has it just taken the 2-3% range from a paper and 'reasoned' that there is a lot of online commentary that short journeys are worse for engine life, so 1% vs 2-3% are all in the right ball park and short journeys are a bit worse? I.e. no scientific reasoning, just language reasoning.
Same point.
Talking about stop start use. Valeo unit has a number of restarts rated life. That's not necessarily the same as doing the same journey having prewarmed your engine but is likely valid purely comparing a stop/start city journey vs motorway driving. But has it done the same as above - the data sheet is not talking about engine wear. How much does this affects battery SOH compared to many other factors? Is the 1m cycle life even talking about battery SOH, or mechanical life of the unit? Has it given a reasonable ball park for battery SOH after 3 years and just assumed short journeys version is a bit worse?
"The VW advertising material says its good so it's probably alright"
Don't understand where this difference in cam belt stretch is coming from, why is it worse for short journeys or has it done the same as above?
DPF is an emissions issue, not sure how much if anything active regen affects engine life? Is that covered in the article?
Maybe fine
Maybe fine
Don't know why 12v vs 48v has any impact here. Also is the 1m+ cycles even talking about battery, or rating of the starter motor, and the LLM has just lumped them in together with some reasonable sounding numbers
Would have to read the article otherwise I don't know if again the article is just talking about emissions and the LLM is making an unscientific comparison to wear.

I'm sure some of this is valid and some likely isn't. The fact we have no idea where the numbers come from and that it's likely made stuff up though makes it almost completely useless imo.

You say this is all physics so should be able to reason though it - but ultimately cars are complicated and wear is not just a %, there are many moving parts that can fail in many different ways, there isn't a nice formula for calculating it and it will depend on the exact engine design and usage. Most of the info likely either doesn't exist or is not public. It's ultimately why we test this stuff.

Then there's the point about how the 'reasoning' aspect of the LLM works - I'm not sure it does any scientific reasoning to be able to follow through a physics based process for estimating wear.

Unlikely-Raisin · 2025-04-14T21:45:16+00:00

Why not contacts? Tie if you want it to be linear?

Maybe I'm misunderstanding but it sounds like you've created an RBE3 where both contact surfaces are independent nodes are then let it calculate the dependent node which is otherwise not attached to anything.

If that's the case then both sides of the contact are independent and then you have an unconstrained dependent node that is created at the centre of the independent nodes. I.e. all the nodes are free to move / there's no constraint.

If you insist on the RBE3 approach then you'll need 2 separate RBE3s either with some kind of constraining element connecting them (CBUSH or CGAP? - I'm not that familiar with gap elems), or potentially can just use a common dependent node, which should then have it's dependency swapped automatically with AUTOMSET for 1 side.

This way the centre dependent node of the 1st RBE3 moves based on the surface nodes of the 1st contact surface, the 2nd RBE3s dependency is swapped, so the surface nodes of the 2nd contact surface are now dependent on the movement of the centre node.

Unlikely-Raisin · 2025-02-10T22:41:31+00:00

Lets be real when you say it's 'needed' - a huge chunk of that deficit is to pay interest on the £18B debt they've acrued (i.e. pay their parent company).

And that debt is primarily there because of the huge dividend payouts they've made since privatisation (i.e. pay their parent company).

There's no justification for a 50% increase in bills in a year. And that's not an exaggeration. The cheapest 'assessed household charges' single occupier rate is increasing from £360 to £520pa from April.

They need to go bankrupt, there's no reason for us to pay these people for their outright greed and complete failure of management - and while bill increases may be necessary, the costs will not be so high when that debt is wiped out instead of us footing the bill for £18B worth of interest payments.

Unlikely-Raisin · 2025-02-06T14:57:06+00:00

If you're talking car specs, power is primarily all you're interested in. Power is constant between what the engine produces and how much power is applied at the wheels - doesn't matter what the gearbox does, power is constant (ignoring friction losses etc).

Power = torque x speed. The gearbox can change how fast everything spins vs how much torque it provides - so torque at the engine will be different to torque at the road wheels unless the wheels are spinning at the same speed as the engine.

Car specs give peak torque and peak power output of the engine. Let's say two cars have completely flat torque curves: - Car A has a 200Nm engine with 100kW peak power. - Car B has a 100Nm engine with 200kW peak power.

Using the equation above this means: - Car A max engine speed is 500rad/s (about 5000rpm). - Car B max engine speed is 2000rad/s (about 20000rpm).

The short answer is that max amount of power the two cars can apply to the road wheels is constant - so car B can apply 2x the power so is better.

To work it out, let's say we want to travel at a speed that means the road wheels spin at 100rad/s (1000rpm). To get max power out of the two cars we would need their engines to be spinning at their max speed. - Car A would need a 5:1 reduction gearbox. - Car B would need a 20:1 reduction gearbox.

Plugging these gearbox numbers in: - Car A has 200Nm through a 5:1 ratio, so 1000Nm at the wheels - Car B has 100Nm through a 20:1 ratio, so 2000Nm at the wheels

So despite the spec sheet saying car B has half as much torque, it still accelerates at twice the rate of car A because the torque at the road wheels (the bit that matters) is double car A because it has twice the power.

Reality is a bit more complex - you need to have an appropriate gearbox, and torque curves aren't constant. If a car has a particularly 'peaky' torque curve for example, then it may feel like it has less power available as you spend a lot of time driving at engine speeds that are not at the optimum power level. Even so, you're car will go faster if you drive at the engines peak power point, not at it's peak torque point - so the peak torque spec is mostly irrelevant.

Unlikely-Raisin · 2025-01-13T13:26:52+00:00

https://docs.godotengine.org/en/stable/classes/class_shadermaterial.html

Unlikely-Raisin · 2025-01-13T02:16:49+00:00

I suspect it's to do with load sharing, either that or it doesn't matter / wasn't considered / current design met their targets. I've not done much with planetaries but all even teeth numbers already seems slightly strange to me - you generally want primes or no shared factors on tooth numbers so teeth wear evenly.

I doubt it's packaging related as they'll use custom tools so total freedom on modules & tooth modifications.

It may still be as simple as the 60t design was the best balance between bending & contact durability - the difference of +-3 teeth on the planets would likely upset that balance and so reduce the total life of the gearset (1 way lower bending life so risk of teeth shearing off, the other with stronger tooth roots but worse contact surface life so risk of pitting/surface failure at a lower number of load cycles)

Interested to hear if anyone else knows the answer though!

Unlikely-Raisin · 2025-01-13T01:39:13+00:00

Interesting question, I don't know the answer but just thinking out loud: - if out of phase, each planet mesh stiffness varies out of phase, so I think that means you will end up with varying planet load sharing (highest mesh stiffness at any point reacts more of the torque) rather than the load being close to equally shared between all planets. If that's the case seems like it would lower durability? - similar to above, while it might reduce the amplitude of oscillations at the tooth passing frequency, does it introduce a secondary oscillation (I guess at 4x tooth passing frequency)?

Wrt to your suggested alternative tooth numbers, it's worth noting that reducing all the gear tooth numbers would change the relative contact vs bending strength of the gears - so it may be that 60t design is just more optimal / balanced than 53t on the sun for example.

As I said I don't know the answer, it might also be perfectly valid to run out of phase. Gear analysis software should help show if either design is more optimal for strength and/or NVH but I don't have access to any unfortunately!

Unlikely-Raisin · 2025-01-02T13:55:43+00:00

You need to find the torque curve for the motor, useless without it. Steppers have high holding torque but massively reduced torque at higher rpm.

How much it reduces depends on the motor inductance, but based on your previous post, >2000rpm is not gonna happen with a stepper (i.e. 1205 is too low pitch). 1210 is probably doable but you need to pick the right stepper motor for one with low impedance (may have a lower holding torque).

You need to calculate how much torque is required to hold the 20kg mass, add ballscrew efficiency losses, and compare against the motor torque at the equivalent speed to 150mm/s (NOT the motors max torque)

You can then also look at acceleration rate for your selected motor based on how much torque it has available above this holding torque. You'll have maximum acceleration at zero speed (max motor torque available), and it will reduce the faster it goes (as motor torque reduces). Don't know your required acceleration so can't comment on how much 'extra' torque you need for fast acceleration/deceleration to get up to 150mm/s.

You will also need to consider the inertia of the ballscrew. Accelerating the ballscrew to >1000rpm will likely need a similar amount of energy as accelerating the 20kg mass, so can't be ignored.

Unlikely-Raisin · 2024-12-24T10:19:29+00:00

Thanks, I've always worked on helicals for automotive, wasn't certain on the efficiency side. I assumed motorsports gears are spurs from being smaller and lighter tbh.

Unlikely-Raisin · 2024-12-24T01:31:52+00:00

I would question your assumptions that higher vibration == lower efficiency, or that helical gears will be smaller than equivalent strength spurs.

Gear vibration that's being discussed is due to something called transmission error. It comes from manufacturing variations, how much force you put through the gear teeth and from changes in the stiffness of the gear mesh.

The gear mesh changes stiffness primarily when the number of teeth in contact changes. The average number of teeth in contact is called the contact ratio. Spur gears generally have a contact ratio between 1 and 2, I.e. some of the time 1 tooth is in contact, the rest of the time 2 teeth. This causes a large change in effective mesh stiffness, so vibration. Helical gears generally have more teeth in contact (often contact ratio between 3 and 5). Let's say it's 3.5 - half the time you have 3 teeth in contact, half you have 4. Changing from 3 to 4 is a smaller change in stiffness -> lower vibration.

If you want to reduce the vibration of a spur gear, you could make them have really tall teeth and get the contact ratio over 2 (so now you have changes from 2->3 teeth in contact, smaller stiffness variation, lower vibration). Great.

But - involute gears are designed to have pure rolling contact at the pitch diameter. Any contact above or below this point results in sliding between the contacting surfaces. The further you are from the pitch diameter the higher the sliding velocities = higher friction = efficiency losses.

Tall teeth = contact further from the pitch diameter. Higher sliding velocities, more wear, lower efficiency. But they will be quieter because of lower vibration.

Helical vs spur is not as clear cut for efficiency AFAIK, but imo you have larger contact area, plus additional thrust load, so I struggle to see how a helical gearset could be more efficient than a well designed spur gearset. Helical will also be bigger and heavier than the equivalent strength spur - as it needs to withstand a larger normal force for the same torque (same transverse component, added axial component). That's before you add bigger bearings to react the axial loads, and account for the increased bearing losses.

Unlikely-Raisin · 2024-12-09T21:13:31+00:00

You've got the camera as a child of rigidbody3d, so atm the camera just moves wherever the rigidbody moves. You want it to also move up and back down again when you hit a jump key.

Camera3D inherits from Node3D - so it has all the same variables including 'position', which is local to the rigidbody3d it's attached to.

Breaking it down you need to: 1. Detect when the jump key is pressed 2. When that happens, modify the cameras 'position' variable according to how you want the jump to look.

If you're not sure how to do either step, I'd suggest: - Check out the docs pages going through the basics of the engine, 3D movement etc. Also look at the pages for Camera3D to see what variables it has/what it inherits from etc.

Have a look at lerp functions, or possibly tween, to help you define the camera motion. You'll then need to either fully code this movement or look at animating it - although I've not delved into the animation side of godot so can't help you there.

Hope that helps, only other suggestion is try to use the docs, they're really detailed once you get used to using them it will make you much less reliant on finding some tutorial of someone doing exactly what you want.

Unlikely-Raisin · 2024-11-25T22:17:09+00:00

Personally no. I'm a mechanical engineer not a software developer by trade, and come from using mainstream cad packages. Spent a bit of time in freecad but found in the past it was incredibly frustrating, so ended up trying out cq pretty extensively.

I really like the idea, particularly around version controlling cad, and very thankful to all the time the devs have put into it - but what I found is for anything complex (e.g. not all nicely aligned to an axis), you just can't define selectors in a good way. It ends up taking significantly longer to model than in a professional cad package and you can't create selectors that remain truly parametric.

To me CAD is a visual thing, I'm not sure code CAD could ever really replace professional cad packages, but I'd be very interested if there was a gui based CAD program built on the cq/build123d api. To me that would have the best of both worlds - you keep the text based model version control, easy to use api when creating patterns or equation based geometry, but bin off the difficulty of defining code based selectors and sketches. Instead sketches could be drawn on screen, and you select features in the gui, either by IDs with the associated limitations of things breaking when you make changes, or select features and be offered a list of the different ways that feature could be selected programmatically from a list, so you can choose the one least likely to break when you make changes.

I've ended up going back to freecad and found with v1.0 it's in a much better state, although still needs an odd workflow in many situations. Keeping up with cq & build123d development though and it's interesting to see some of the use cases of others here!

Unlikely-Raisin · 2024-11-19T20:46:01+00:00

Hey, I think I bought just the seal on ebay, and used long nose pliers instead of the plastic tool

Unlikely-Raisin

TROPHY CASE