Teminology: four corner scoring on piston

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Teminology: four corner scoring on piston

Post by Bear45-70 » Sun Jan 15, 2012 2:29 pm

I've wanted to ask this since you first posted this. "How did you get corners on a round cylinder and piston?"


Mod: This is split from another thread. We have strong discussion on validity it's name, and some technical info.

-- Couple thoughts --
Googling the term does give hits as posters have suggested. In a general sense, we should have a piston failures wiki topic. We could add local information (wikispredia) and links to cover this term.

What is the definition of four corner scoring?
Has this faiure gone by other names in the past?
What are its causes and mitgations?

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Terminology discussion: four corner scoring on piston

Post by guen84 » Wed Jan 18, 2012 6:46 pm

Bear45-70 wrote:
guen84 wrote:i recently took my 51mm mini stroke top end apart, found major four corner scoring and carbon build up on under side of piston. .....................................................
I've wanted to ask this since you first posted this. "How did you get corners on a round cylinder and piston?"

simple geometry my grizzly, when it comes to a piston it would be the four sides next to the wrist pin since they are the thickest part of the piston they will hold heat longer than any other part of the piston.... so what do i owe the honor of the (great)bear45-70 and the (great)maddog too both nit pick my post.. bear your lucky i gave you the answer poor maddog still trying to find out what a dictionary is.. SO TO BOTH OF YOU TRY GOOGLE'IN YOUR STUPID QUESTIONS BEFORE YOU TRY AND START A FIGHT.. CAUSE THATS ALL BOTH OF YOU GUYS DO ON THIS SITE!!!! :evil: baka knew exactly what i was talking about did he google it or humm maybe he knows what his s***??? :wink:
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Re: four corner scoring on piston

Post by bakaracer » Wed Jan 18, 2012 7:08 pm

thats why i have been saying on the taiwan bores you need to run a flex hone through it and round the edges on the piston and put a angle around the edges of the skirt and and straight edge on the piston so it can grab oil. also if using pump gas you need to lower the compression to lower the compression ratio to be stable for pump gas,if not its going to run hot and no matter if there is oil getting between the piston from shamfering the piston. it will still seize as the temp of aluminum melting will be reached.
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Re: four corner scoring on piston

Post by Bear45-70 » Wed Jan 18, 2012 7:40 pm

guen84 wrote:
Bear45-70 wrote:
guen84 wrote:i recently took my 51mm mini stroke top end apart, found major four corner scoring and carbon build up on under side of piston. .....................................................
I've wanted to ask this since you first posted this. "How did you get corners on a round cylinder and piston?"

simple geometry my grizzly, when it comes to a piston it would be the four sides next to the wrist pin since they are the thickest part of the piston they will hold heat longer than any other part of the piston.... so what do i owe the honor of the (great)bear45-70 and the (great)maddog too both nit pick my post.. bear your lucky i gave you the answer poor maddog still trying to find out what a dictionary is.. SO TO BOTH OF YOU TRY GOOGLE'IN YOUR STUPID QUESTIONS BEFORE YOU TRY AND START A FIGHT.. CAUSE THATS ALL BOTH OF YOU GUYS DO ON THIS SITE!!!! :evil: baka knew exactly what i was talking about did he google it or humm maybe he knows what his s***??? :wink:
You can spout all the BS you want, but around object do not now or never will have corners. Oh, in simple or complex geometry round objects still don't have corners. Education system fail again.
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Re: four corner scoring on piston

Post by deuce217 » Thu Jan 19, 2012 2:31 am

:coolcruise:

You can spout all the BS you want, but around object do not now or never will have corners. Oh, in simple or complex geometry round objects still don't have corners. Education system fail again.[/quote]

I guess Bear requests quadrants there can be be corners if a circle is divided into them. Geez, take it easy guys this is a forum not a classroom. Calm down read this http://www.mathwords.com/q/quadrants.htm lol
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Re: four corner scoring on piston

Post by Bear45-70 » Thu Jan 19, 2012 2:56 am

deuce217 wrote::coolcruise:

You can spout all the BS you want, but around object do not now or never will have corners. Oh, in simple or complex geometry round objects still don't have corners. Education system fail again.
I guess Bear requests quadrants there can be be corners if a circle is divided into them. Geez, take it easy guys this is a forum not a classroom. Calm down read this http://www.mathwords.com/q/quadrants.htm lol[/quote]

I require simple logic and a circle does not now and never will have corners. *, look up the definition of a corner and then explain how a circle can have one much less four corners.
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Re: four corner scoring on piston

Post by deuce217 » Thu Jan 19, 2012 3:26 am

Bear45-70 wrote:
deuce217 wrote::coolcruise:

You can spout all the BS you want, but around object do not now or never will have corners. Oh, in simple or complex geometry round objects still don't have corners. Education system fail again.
I guess Bear requests quadrants there can be be corners if a circle is divided into them. Geez, take it easy guys this is a forum not a classroom. Calm down read this http://www.mathwords.com/q/quadrants.htm lol
I require simple logic and a circle does not now and never will have corners. *, look up the definition of a corner and then explain how a circle can have one much less four corners.[/quote]

I will not argue that Bear, Im just saying most fellas don't talk about these subjects on the same level as a mechanical engineer or a machinist.
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Re: four corner scoring on piston

Post by Bear45-70 » Thu Jan 19, 2012 12:56 pm

deuce217 wrote:
Bear45-70 wrote:
deuce217 wrote::coolcruise:

You can spout all the BS you want, but around object do not now or never will have corners. Oh, in simple or complex geometry round objects still don't have corners. Education system fail again.
I guess Bear requests quadrants there can be be corners if a circle is divided into them. Geez, take it easy guys this is a forum not a classroom. Calm down read this http://www.mathwords.com/q/quadrants.htm lol
I require simple logic and a circle does not now and never will have corners. *, look up the definition of a corner and then explain how a circle can have one much less four corners.
I will not argue that Bear, Im just saying most fellas don't talk about these subjects on the same level as a mechanical engineer or a machinist.[/quote]

I'm neither of those and would never claim to be. But I know that a corner has a sharp point to be a corner and circles do not.
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Re: four corner scoring on piston

Post by ZMUD » Thu Jan 19, 2012 4:43 pm

Bear45-70 wrote:I'm neither of those and would never claim to be. But I know that a corner has a sharp point to be a corner and circles do not.

But you sure have alot to say about something you now nothing about! :*: :crazy:
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Re: four corner scoring on piston

Post by Bear45-70 » Thu Jan 19, 2012 4:50 pm

ZMUD wrote:
Bear45-70 wrote:I'm neither of those and would never claim to be. But I know that a corner has a sharp point to be a corner and circles do not.

But you sure have alot to say about something you now nothing about! :*: :crazy:
Wrong dogbreath, but I took Algebra in the last century and guess what, corners were pointie even back then. Crap, dealing with those that were sent to a failed education system that thinks failing to understand is OK makes teaching them impossible. Thanks liberal educators of America. :roll:
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Re: four corner scoring on piston

Post by Wheelman-111 » Thu Jan 19, 2012 5:15 pm

Greetings:

I think he means the edges of the cutouts in the piston below the wrist pin.
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So, yes a cylinder has no corners. Unless you cut an arch into it... Sheesh, what are y'all in Kindergarten?
Zee-Mud, I need a close-up of your avatar for um... scientific research. Yeah, that's it! Science!!
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Re: four corner scoring on piston

Post by deuce217 » Fri Jan 20, 2012 12:42 am

Wheelman-111 wrote:Greetings:

I think he means the edges of the cutouts in the piston below the wrist pin.
Image
Image
So, yes a cylinder has no corners. Unless you cut an arch into it... Sheesh, what are y'all in Kindergarten?
Zee-Mud, I need a close-up of your avatar for um... scientific research. Yeah, that's it! Science!!
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Re: four corner scoring on piston

Post by Bear45-70 » Fri Jan 20, 2012 12:54 am

deuce217 wrote:
Wheelman-111 wrote:Greetings:

I think he means the edges of the cutouts in the piston below the wrist pin.
Image
Image
So, yes a cylinder has no corners. Unless you cut an arch into it... Sheesh, what are y'all in Kindergarten?
Zee-Mud, I need a close-up of your avatar for um... scientific research. Yeah, that's it! Science!!
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Re: four corner scoring on piston

Post by guen84 » Sat Jan 21, 2012 4:15 am

bear Google 4 corner seizers, then talk s***. ill make sue I post some pics when I get a chance. so then maybe u will under stand the point. of the. thread.
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Re: four corner scoring on piston

Post by Bear45-70 » Sat Jan 21, 2012 11:30 am

guen84 wrote:bear Google 4 corner seizers, then talk s***. ill make sue I post some pics when I get a chance. so then maybe u will under stand the point. of the. thread.
Just because the world is full of morons that post BS on the net, does not now and never will make a round object have corners. Or are you really so dense you can't figure that out? Hummmmm......maybe your are.
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