Titanium vs. Stainless Steel

[tomek]

26 minutes ago, fizzy said:

You are missing our point, again. We or you, don't know what engine they are comparing to, which is why their claims of greatness are suspect. 

 

Can I presume you don't know the meaning of my reference to "jerk"?

I was not referring to their claims, greatness, etc. The text is absolutely correct from physics point of view. That's all.

 

Jerk? That would be me sometimes.

Seriously, you referred to what is happening during initial phase of valve opening. Cam lobe in not supposed to "hit' valve at high speed becouse you get what? Bounce.

It applies to closing stages as well, valve not supposed to hit' valve seat at high speed. 

 

[tomek]

31 minutes ago, SwampNut said:

 

Is it something like "professional?"

 

I also think their pitch sounds like, "But wait, there's more!"

 

 

3 hours ago, tomek said:

 

 

Btw, Swamp will be here shortly.

Lol. One doesn't have to be Nostradamus to predict future here at .org.

[fizzy]

4 minutes ago, tomek said:

I was not referring to their claims, greatness, etc. The text is absolutely correct from physics point of view. That's all.

 

Jerk? That would be me sometimes.

Seriously, you referred to what is happening during initial phase of valve opening. Cam lobe in not supposed to "hit' valve at high speed becouse you get what? Bounce.

It applies to closing stages as well, valve not supposed to hit' valve seat at high speed. 

 

Jerk is an engineering term meaning rate of change of acceleration. 

[tomek]

5 minutes ago, fizzy said:

Jerk is an engineering term meaning rate of change of acceleration. 

That would be "yank" in United States obviously.

[fizzy]

This reminds me of a test question on the PE exam I took in the min 90's. I swore an oath not to reveal anything about said test, but enough time has passed. I will lay it out if there is any interest.

[tomek]

52 minutes ago, fizzy said:

This reminds me of a test question on the PE exam I took in the min 90's. I swore an oath not to reveal anything about said test, but enough time has passed. I will lay it out if there is any interest.

Go ahead. 

[fizzy]

1 hour ago, tomek said:

Go ahead. 

Quote

Consider:

A round disc radius r is rotating clockwise about a point distance d from the disc center. A cam follower is touching the disc at it rotates.

K, m, d, r and any other pertinent info is given (metric).

 

Question:

What is the max rpm of the disc before the cam follower leaves the surface of the disc. 

[tomek]

1 hour ago, fizzy said:

Consider:

A round disc radius r is rotating clockwise about a point distance d from the disc center. A cam follower is touching the disc at it rotates.

K, m, d, r and any other pertinent info is given (metric).

 

Question:

What is the max rpm of the disc before the cam follower leaves the surface of the disc. 

That would be fairly easy. First we would have to create calculus for the movement of the rod. It can be easily done by creating two geometric equations. We know d and the angle of rotation of the cam. So we can find x and y.

 

From second one we can calculate z , or essentially the movement of the rod. 

Pretty much done. 

 

 

 

 

[tomek]

Would be more fun with progressive rate spring.🤪

[fizzy]

1 hour ago, tomek said:

That would be fairly easy. First we would have to create calculus for the movement of the rod. It can be easily done by creating two geometric equations. We know d and the angle of rotation of the cam. So we can find x and y.

 

From second one we can calculate z , or essentially the movement of the rod. 

Pretty much done. 

 

 

 

 

"Pretty much done"  No. 

That is the very first step of many many steps. 

I will say you are pointing in the right direction, so, good job.

This section of the test gave 60mins, or actually, 4 hrs to do any 4 out of 8 questions. I guess this was the easiest as I remember doing it first. 🍺

 

[tomek]

3 minutes ago, fizzy said:

"Pretty much done"  No. 

That is the very first step of many many steps. 

I will say you are pointing in the right direction, so, good job.

This section of the test gave 60mins, or actually, 4 hrs to do any 4 out of 8 questions. I guess this was the easiest as I remember doing it first. 🍺

 

I mean, last time I had to deal with things of that nature was in mid 80's so don't expect me to remember  advanced math. 

But coming up with mathematical equation for the movement of the rod vs. cam angle is the main thing here. Maybe, maybe after completing it would be clearly apparent at what angle of rotation the acceleration is the greatest. Maybe.

 

Back when I was at peak form it would take me about 10-15:minutes to deal with it. 

Now, 4 of those would be entirely different story, we all know after extended period of intense thinking brain starts to smoke, and becomes useless.😁

[fizzy]

6 minutes ago, tomek said:

I mean, last time I had to deal with things of that nature was in mid 80's so don't expect me to remember  advanced math. 

But coming up with mathematical equation for the movement of the rod vs. cam angle is the main thing here. Maybe, maybe after completing it would be clearly apparent at what angle of rotation the acceleration is the greatest. Maybe.

 

Back when I was at peak form it would take me about 10-15:minutes to deal with it. 

Now, 4 of those would be entirely different story, we all know after extended period of intense thinking brain starts to smoke, and becomes useless.😁

But coming up with mathematical equation for the movement of the rod vs. cam angle is the main thing here. yes

then:

Differentiate the formula of position to get the formula for velocity.

       "                "       "         "  velocity to get the formula for acceleration

set this formula against the potential acceleration generated by the spring.

 

In all my years working, I never ever had to do any calculus. Very little math really, compared to the stupid amount I had to learn. 

 

         

[superhawk996]

It comes as no surprise that the acetone huffing Professional is the only one sold by the BS.  Also not surprising that he's pretending to have a build that he'll pretend to hide from us.

[SwampNut]

Remember that PPE is not necessary when using acetone in an enclosed space.  The label only said not to "intentionally" concentrate it.

 

I know it's marketing, but every time I run into something that's over-stated I go the other direction.  Like when Startron printed the claim that it reduces the RPM for a given prop speed.  One slice of bullshit ruins the whole pepperoni pizza.

 

 

[jon haney]

20 hours ago, tomek said:

Would be more fun with progressive rate spring.🤪

You and I have different definitions of "fun".🤪

[jon haney]

18 hours ago, fizzy said:

But coming up with mathematical equation for the movement of the rod vs. cam angle is the main thing here. yes

then:

Differentiate the formula of position to get the formula for velocity.

       "                "       "         "  velocity to get the formula for acceleration

set this formula against the potential acceleration generated by the spring.

 

In all my years working, I never ever had to do any calculus. Very little math really, compared to the stupid amount I had to learn. 

 

         

Related to the actual Question:  (What is the max rpm of the disc before the cam follower leaves the surface of the disc?)

I believe we would need to know spring rate, starting seat pressure, effective mass of the follower/spring combo, and any friction of movement of the follower.  As Tomek would say, Fun stuff.

[fizzy]

1 hour ago, jon haney said:

Related to the actual Question:  (What is the max rpm of the disc before the cam follower leaves the surface of the disc?)

I believe we would need to know spring rate, starting seat pressure, effective mass of the follower/spring combo, and any friction of movement of the follower.  As Tomek would say, Fun stuff.

Per my post "K, m, d, r and any other pertinent info is given (metric)."

On the actual test they expected an actual rpm result. 

I don't remember the actual numbers but I can make some up if you want to grind it out.🍺

[jon haney]

26 minutes ago, fizzy said:

Per my post "K, m, d, r and any other pertinent info is given (metric)."

On the actual test they expected an actual rpm result. 

I don't remember the actual numbers but I can make some up if you want to grind it out.🍺

That's okay.  My college era math skills are mostly gone, too.  Was just pointing out other factors that would affect a real world result.  I always laughed at all the text book problems that would state:  "assuming an ideal gas" or "assuming constant temperature".

[SwampNut]

4 minutes ago, jon haney said:

"assuming an ideal gas" or "assuming constant temperature".

 

I once answered that since the book said that all laws of physics were suspended, therefore anything is possible, and I made up something insane.  I got a pass, as I was technically correct, the best kind of correct.

 

[fizzy]

3 minutes ago, SwampNut said:

 

I once answered that since the book said that all laws of physics were suspended, therefore anything is possible, and I made up something insane.  I got a pass, as I was technically correct, the best kind of correct.

 

If you pulled that stunt in engineering school, you would end up with a degree in business admin. 

[superhawk996]

On 12/22/2022 at 11:59 AM, fizzy said:

If you pulled that stunt in engineering school, you would end up with a degree in business admin. 

Or a truck driver's license.

[tomek]

Yep. Two clueless never know when to shut up. ignorant on this particular subject morons showed up. As I predicted. Lol. That's why there won't be built thread. Don't blame me. I'm not gonna deal with one or both of them doing their idiotic best to fuck up my posts. Been there, not doing again.

 

Btw, it is almost done. New valve job by KWS, Kent cams, cams have been degreed, valve clearance adjusted, piston to valve clearance checked. Waiting for main bearings. One looks like squirrel took a bite of it. No clue why. Decided to replace all of them. Only 85 bucks. 

 

 

Edited December 24, 2022 by tomek

[tomek]

I moved engine to laundry room. Too cold in garage. 

 

Kent cams have this nice future allowing to use 24 mm wrench to hold or move cams when adjusting timing. Makes the process so much quicker. 

 

 

Edited December 24, 2022 by tomek

[tomek]

Check out assymetrical profile of camshafts. According to our Cuban experts, higs school dropouts clueless about basic physics, it is all Bull Shit marketing. Lol. Kent and OEM have similar profiles, more lift in case of aftermarket.

 

 

[SwampNut]

It's great when the fish jump in the boat.  Nice work.