match weighing pistons

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radish
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match weighing pistons

Post by radish » Fri Feb 03, 2017 10:25 am

HI

I have just weighed my pistons and the difference is 0.3g. I have also matched the pins, clips and rings and as a complete unit i can get them all within 0.4g.
it is the 1 of the pins that is where the difference is 1.5g, Is it advisable to remove material from the ID of the pin?

Cheers

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Piledriver
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Re: match weighing pistons

Post by Piledriver » Fri Feb 03, 2017 12:15 pm

Yes.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

radish
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Re: match weighing pistons

Post by radish » Fri Feb 03, 2017 1:10 pm

Thanks very much.

Ol'fogasaurus
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Re: match weighing pistons

Post by Ol'fogasaurus » Fri Feb 03, 2017 4:04 pm

I think "where is also in the picture too. In the wrong place you could have problems. I remember hearing this being a problem years ago and I think things haven't changed that much.

radish
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Re: match weighing pistons

Post by radish » Fri Feb 03, 2017 5:50 pm

Ol'fogasaurus wrote:I think "where is also in the picture too. In the wrong place you could have problems. I remember hearing this being a problem years ago and I think things haven't changed that much.
I would of thought through the hole at each end so it's equal?
I am confused that the total mass I can get equal but would still need to do the pin.

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Piledriver
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Re: match weighing pistons

Post by Piledriver » Sat Feb 04, 2017 1:12 am

Sometimes there is a bit of flash in the middle you can smooth out, but the weight needs to come off the ends.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

Ol'fogasaurus
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Location: Just north of Seattle

Re: match weighing pistons

Post by Ol'fogasaurus » Sat Feb 04, 2017 9:54 am

Thank you Pile. I still have my "think about it" habit from being a "checker/mentor" of others work for over 30 years. I point out something and if they find the answer themselves they are more apt to remember it than if I give them the answer. Sorry!

Ol'fogasaurus
Posts: 13218
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

Re: match weighing pistons

Post by Ol'fogasaurus » Sat Feb 04, 2017 10:17 am

I did a quick search on balancing and got a great answer from Eaton:

http://www.eatonbalancing.com/blog/2007 ... ng-part-3/

Here are some more I found. There is a lot of info, including videos, depending on how you word the search:

http://aircooledtech.com/balancing/

viewtopic.php?t=124244

http://aircooledtech.com/balancing/

http://www.shoptalkforums.com/viewtopic.php?t=42324

Also remember that taking weight from the wrong place can weaken the piston catastrophically.

radish
Posts: 9
Joined: Thu Mar 04, 2010 5:18 am

Re: match weighing pistons

Post by radish » Sat Feb 04, 2017 1:52 pm

Thanks, that info at Eaton is great.

radish
Posts: 9
Joined: Thu Mar 04, 2010 5:18 am

Re: match weighing pistons

Post by radish » Mon Feb 06, 2017 6:27 pm

Crisis over, I re weighed on 2 different scales today and the original weights were incorrect! Now I'm lucky enough to have access to a laboratory with plenty of weighing equipment not £15 kitchen scales but these cost between £700-2500. So all good now.
Thanks for your help.

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