Engine machine shop destroyed my block

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Dave Koehler
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Re: Engine machine shop destroyed my block

Post by Dave Koehler »

groberts,
You assume there was an error by a shop of .0015.
If the poster can't write it down correctly it brings in doubt of how it was measured, what with, calibration and the temperature difference.
If it was written correctly then it is much ado about nothing.

John@RED, want to follow up on this so this can be put to bed before it gets more out of hand?
Last edited by Dave Koehler on Mon May 07, 2018 10:35 am, edited 1 time in total.
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Re: Engine machine shop destroyed my block

Post by Walter R. Malik »

John@RED wrote: Mon May 07, 2018 8:03 am A wonderful engine machine shop just made the bores 0.00008 to 0.00015 bigger than what I asked:
what can I do now to save the block, except sleeving it, beside asking them for damages?
:evil:
I hope this is a misprint or a typo ... a tenth and a half thou over ...?
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Re: Engine machine shop destroyed my block

Post by groberts101 »

Dave Koehler wrote: Mon May 07, 2018 10:18 am groberts,
You assume there was an error by a shop of .0015.
If the poster can't write it down correctly it brings in doubt of how it was measured, what with, calibration and the temperature difference.
Probably much ado about nothing.

John@RED, want to follow up on this so this can be put to bed before it gets more out of hand?
As others have also eluded to.. just seemed like a logical assumption since I know of no "engine machine shop" short of maybe an areospace manufacturing facility that could even measure such an infinitesimal number. As also mentioned it would probably need to be measured inside a highly temperature controlled sealed chamber to even come close to that resolution. Not sure.. maybe even a laser based measuring system of some sort?

My apologies if I seemed to say that anyone posting early on was inept in any way shape or form. Was not my intention in the least since guys like you do this stuff for a living and I do it out of a garage based workshop while hanging on longer coattails just to figure it all out. :D

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Re: Engine machine shop destroyed my block

Post by Warp Speed »

tenxal wrote: Mon May 07, 2018 8:57 am
John@RED wrote: Mon May 07, 2018 8:03 am A wonderful engine machine shop just made the bores 0.00008 to 0.00015 bigger than what I asked:
what can I do now to save the block, except sleeving it, beside asking them for damages?
:evil:
Please describe the measuring process used to determine 80-150 millionths.
Air gauge......
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Re: Engine machine shop destroyed my block

Post by piston guy »

I suggest measuring the piston diameters for variance and placing them to your advantage. I'm sure there is some variance in diameter among them.
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Re: Engine machine shop destroyed my block

Post by ProPower engines »

Before I got bent out of shape about a measurement between your measuring instruments and the shops tools I would do a direct comparison at the same temperature.
I have run into this same issue a few times over the years where a DIY'r that has basic measuring tools tells me to make it a specific number only to find out he has a bore gauge that does not read in 10th's but is guessing as he has a gauge that reads in 1/2's and imagines the between numbers. While it can be close its not perfect.
Not if you have a gauge that reads 10th's as does the shop then calibrate your tool and go back and recheck it.

You may find it may be dead on or not as bad as you think it is. Or it can be worse.

But I would not get to upset at .0005" over what you asked for but more then that I would not accept if you are both working with similar tooling and temp in both shops.
I like to take critical measurements in the morning so the heat of the day does not influence sizing as much before the shop gets heated as well as everything else in the shop.
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Re: Engine machine shop destroyed my block

Post by tjz450 »

I took the OP's post as total sarcasm, to bait and spool up the membership. May have worked.
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Re: Engine machine shop destroyed my block

Post by John@RED »

tjz450 wrote: Mon May 07, 2018 2:17 pm I took the OP's post as total sarcasm, to bait and spool up the membership. May have worked.
Ah ah, sorry guys for the zero more there.... #-o
I obviously was talking about .0008 - .0015 more than what I asked.
I know it could seem not to be a lot, but in this little engine suggested piston to wall is .0032, so .0015 is about a 50% too much.

As someone wrote in the first page, I was just told by them that heated by the coolant during machining the clearance was ok, and they too see that back to ambient temp the clearance was the same i got:
I know that this may happen in some blocks, but thought .0015 to be too much
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Re: Engine machine shop destroyed my block

Post by ProPower engines »

Well that said more details regarding what engine it is and it's intended usage as well as piston type etc would go along way to getting any help that would be useful in your case.

The omission of the details of it being hot honed changes everything.
That said if you can post what pistons etc. guys that have done similar builds can ad info more helpful.
But if you are checking a block that was hot honed it will change a good amount from heated state to cooled off and the bores in some cases will show up funny sizes at different points in the bore top to bottom.
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Re: Engine machine shop destroyed my block

Post by engineguyBill »

As has been pointed out already in previous posts, the difference between the OP's measurements and the machine shop measurements could very well be attributed to temperature differentials and measuring tool calibration. Personally, I would be more confident in the measurements at the machine shop . . . . . . but, that's just me.
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Re: Engine machine shop destroyed my block

Post by Dave Koehler »

gasses,
Did you read the 3 posts above yours?
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Re: Engine machine shop destroyed my block

Post by tenxal »

Warp Speed wrote: Mon May 07, 2018 11:00 amAir gauge......
I hear 'ya. :wink:

No way was I going there..... :lol:
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Re: Engine machine shop destroyed my block

Post by modok »

Just in case, you didn't mention....
Was a torque plate used?
Are the skirts coated?
And have you checked the actual clearance comparing skirts to block bore.... or just bore size?

Pistons are getting really good, but I still like to check each one just to be sure.

I;ll assume at worst there could be .0005 difference in measuring due to being a different hand using different measuring equipment, and on a "home gamer" level that could be twice as much. Nothing personal, but it would not be the first time at all.

If the cylinders were heated....they would be larger. They are blowing smoke. But did you buy that? :)
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Re: Engine machine shop destroyed my block

Post by gmrocket »

John@RED wrote: Mon May 07, 2018 3:09 pm
tjz450 wrote: Mon May 07, 2018 2:17 pm I took the OP's post as total sarcasm, to bait and spool up the membership. May have worked.
Ah ah, sorry guys for the zero more there.... #-o
I obviously was talking about .0008 - .0015 more than what I asked.
I know it could seem not to be a lot, but in this little engine suggested piston to wall is .0032, so .0015 is about a 50% too much.

As someone wrote in the first page, I was just told by them that heated by the coolant during machining the clearance was ok, and they too see that back to ambient temp the clearance was the same i got:
I know that this may happen in some blocks, but thought .0015 to be too much
sounds like they are bs'ng you..it would be the opposite of that happening. when it cooled down the bores would get smaller.

being too aggressive with stone load etc can overheat everything and give a false plus reading when checking compared to room temp.

some piston skirt coatings can add what you need.
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Re: Engine machine shop destroyed my block

Post by MadBill »

Line2line was my choice for same...
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