# What's this tool/fixture?



## Playingwithmetal (Feb 21, 2017)

Hey.  I picked this up for a buck at a closing machine/welding shop.  None of the employees were there so I couldn't ask anyone what it was.  I think it's cast iron.  I thought it was some type of lapping plate maybe unfinished. I'm certain someone on here will know exactly what it is. I haven't cleaned it up yet (has bits of rust and grime ect...) to put it on surface plate and indicate it to see if its precision.  
Thanks in advance.


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## Ulma Doctor (Feb 21, 2017)

i have only seen flat lapping plates, but that doesn't mean they don't come with profiles.
by the looks of the photos, i would not say that it is a precision instrument.


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## Glenn Brooks (Feb 21, 2017)

I wonder if this is some kind of die for metal shaping?


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## wawoodman (Feb 22, 2017)

Or just a fixture to lay a round workpiece in, to drill or something?


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## Wireaddict (Feb 22, 2017)

It looks like a bottom/female press brake die to me.


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## Charles Spencer (Feb 22, 2017)

It's a pencil.


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## Silverbullet (Feb 22, 2017)

Looks like a laping block to me. Possibly for doing cast tables.


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## Playingwithmetal (Feb 22, 2017)

That's sure what I thought.  What could the slotting be for other than lapping? Never seen a press die with grooves ?


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## Uglydog (Feb 22, 2017)

What degree is the V groove?
Size?
I'm having difficulty believing that anyone would want to lap a lathe bed.
But....

What does the other side look like? Am wondering if she was re purposed from something. 

Overall size?
She looks ground and not scraped. Is she iron or steel?

Daryl
MN


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## Playingwithmetal (Feb 22, 2017)

Also since we're in the subject, and I need a lapping plate.  Would hand scrapping this against my reference plate make a good lapping plate?  I want a good surface to flatten my deburring and sharpening stones. I have used sand paper on my less precision plate but want a cast iron surface.


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## David S (Feb 23, 2017)

Could this have been some sort of bearing plate and the cross hatches are for oil passages?

David


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## Uglydog (Feb 23, 2017)

Thought you might find the attached interesting.
Especially page 16 of Lapp Tech.
Or Chapter 2 the older Modern Tool Making text.

I was blessed with a flat lap plate several years ago. Some guy pulls into my driveway and knocks on my garage overhead door. Says he heard I did some machine type stuff and they were throwing this away at work. He wasn't real sure what it was. It's maybe 16x20. She is fun to use, that is unless you expect to see chips fly as a metric for progress.

David S might be correct.
It'd be interesting to identify how this prints.
Do you have any way to blue this up and identify flatness?

Daryl
MN


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## Playingwithmetal (Feb 24, 2017)

Wow.  Thanks Daryl.  I really liked the linked PDF.  I really enjoy old shop articles and info.  I looked high and low online for a pic of the lapping plate with the v.  I think that must be what it is.  It's cast iron.   It has some deep scratches that need to be de burred befor it will blue up at all.  It is definitely ground.  Can a lapping plate be scraped flat? Or am I missing some part of the difference. 
Thanks


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## ziegedw (Feb 25, 2017)

Daryl,

Thank you for sharing these two publications, they are great reference materials.
Especially the one on lapping, I have not seen this kind of detail on the plate wear in other publications before.

I have two cast iron laps, one coarse and one fine grooves for small items, think like barber clipper head size.

Dean Z.


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