Anvil flatness tolerance question

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M_Chavez

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Hi all,

Just hoping for a second opinion on whether I am being unreasonable or not.
Was looking for a benchtop anvil, and found a UK made one from Reclaimed Railway (ebay, etsy, etc). Essentially, it's a 130mm-long chunk of old railway with the top of the rail "machined perfectly flat" according to the seller.
Looked like exactly what I was looking for, so ordered one. When the anvil arrived, I was disappointed to find noticeable "snipe" over about 20-25mm on one edge. I.e. There's a noticeably deeper cut than the rest of the working surface, and it's about 0.5mm deeper. So only 110mm out of 130mm length is dead flat.
Looks like a manufacturing defect to me, so I sent the details to Reclaimed Railway just to get a response along the lines of Sorry, we're not sorry: 0.5mm over 130mm length is within our tolerance for "machined perfectly flat".

My initial reaction is that this is a manufacturing defect and poor QC, but I thought I'd just check that it's not me being picky (as I hate being on the seller end of a nit-picking customer story).

If any of you have noname cast iron benchtop jobbies, how flat is flat?

Thanks.
 
What will you use it for? An anvil will never be a reference plate, so I think tempering expectation is worthwhile. Mine main one is old and noticeably crowned with wear on the edges but I can use this to tweak flatness in what I’m making. I also have a sawyers anvil which is much flatter, and great for straightening, but not really that nice for forging on.
Precision engineering vs smithing.
If I forged stuff to a 0.5mm tolerance I’d be grinning ear to ear
 
Mainly need it to use as a base for (very fine) riveting and straightening (small) flat stock.
I think it's just a big expectation mismatch - having a 0.5mm high spot on a surface that was supposedly "machined perfectly flat" sounds like a botch job to me, but the customer service bottom line is: you're too picky, mate, take it or leave it.

But I guess if that's the industry standard these days, there's no point swapping it for another if it's going to be just as "flat".
 
To give some foundation to your concern, try to find an alternative or equivalent product for sale by anyone, anywhere, where a proper flatness measurement is quoted.

As an analogy, a tape measure might be stated as +/- 1mm per 5 metres.

There is an important distinction between a sales description and an engineering specification.

There is nothing wrong with being picky, but the time to be so is before handing over your money.

Find someone with a metal shaper, planer or surface grinder and pay them to finish it to your requirements.
 
For an anvil you need a smooth surface with well defined edges. If the anvil has a machined step, then it’s not smooth and not really useable in that area as an anvil, you have a legitimate complaint. It it’s smooth with 0.5mm run off, then it’s perfectly useable as an anvil and you have nothing to complain abaout
 
actually it's not so hard to find high grade heavy steel sections with a ground finish.......
either cut to length or an off cut......
I used to use a place in Southampton as it was near the ferry port for France....

try
[email protected] did ok with them, they'll post and cut to size.....
 
Reading the OP carefully, I think they have either altered the depth of cut on the mill after the first 25mm wide pass or the stock has not been properly clamped and has moved for that pass.
In that case, it's just poor workmanship. No excuses. Tell them it isn't as described and they have 15 days to collect it.
0.5mm variation in the surface of an anvil is neither here nor there but this is specifically a machining error and the goods aren't described.
No one with any commercial knauss would describe something as "perfectly flat". It's impossible to achieve and there will always be some customer, somewhere who will call you out on it.
 
Yes, it's a 0.5mm step, not run-off. Thanks folks.

I don't consider that flat and I'm a woodworker(!). I'll be sending it back.
Didn't like the seller's attitude either to be honest.
 
Thanks for the suggestion. What steel offcut to go for? Silver steel would bee too soft, wouldn't it?
 
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I have a rail track section as well. Mine looked as though it had been done by Fred Flintstone using a really coarse file. I just ran over it a few times with a belt sander. Do you actually need it to be perfectly flat? Not sure what scale you are working at but for watch work my "anvil" is a big heavy stainless coffee tamper, beautifully machined and pretty hard.
 
I need it to be flat for flattening jobs, but my issue with the rail, really, is that there's clearly a machining defect on the working surface, and the seller was being rather arrogant in claiming that such poor workmanship is acceptable for a machined surface.
I don't accept such poor surfaces in my woodwork, so a self-proclaimed metalworker should really be ashamed of himself, imho.

There's this thing called a jeweller's "flat stake" or "bench block", which seems to be exactly what I'm after - a flat chunk of hardened steel. I'll see if that suits my needs.
 
I use a sledgehammer head for lots of jobs, mostly gets used for bending metal, and over the leg of the bench for using a punch before drilling.
Club hammer's handy also, and both of them could be used for a peening job.
 
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a 130mm-long chunk of old railway with the top of the rail "machined perfectly flat" according to the seller.
A great way to sell something without being dishonest, using a term like "machined perfectly flat" is vague at best and no different to saying something is "hot" . It might be flat enough for your purpose which is great but when you are talking about something you literally bash metal on then as said it is the finish that is important and not flatness.

So only 110mm out of 130mm length is dead flat.

Without knowing what you are shaping then is either 20mm or 0.5mm critical, 85% is " flat" with 25% 0.5mm less so is this going to impact your objectives ?
 
is this going to impact your objectives ?
Yes, but only marginally. I actually really like the design & the size, but the seller's not interested in sending out a replacement. Go figure.
It's a matter of principle, really: why accept a flawed product, especially if the seller does not admit the flaw or the lack of QC (the step/kink in the working surface can be seen with a naked eye).

None of my own work has ever been perfect, but at least I like to think that I have the decency to admit when I screwed up.
 
Ebay has been ruined by a few who have no interest in the customer, I think it is a minefield these days and has become one of those places you tend to use as last resort. I can fully understand you do not want a flawed product, if everyone rejected second rate products then we would all see a quality improvment.

If you cannot get a return then you need to address the issue, much easier if you have a mill but another option is to use plate glass and emery paper with some effort. Start not to course and work down then polish to a standard you are happy with.
 
I have a piece of RSG which has just been flame cut both to length and part of the web at one end, it seems perfectly flat enough and was given to me by a very skilled model engineer by night and a toolmaker by day, who passed it to me when he picked up a proper anvil. It lays by the door of the shed and I use it on the grass/lawn!
Bloody usefull it is too. It could be made to look a lot nicer but I cannot be bothered,,,
 
I have a piece of RSG which has just been flame cut both to length and part of the web at one end, it seems perfectly flat enough and was given to me by a very skilled model engineer by night and a toolmaker by day, who passed it to me when he picked up a proper anvil. It lays by the door of the shed and I use it on the grass/lawn!
Bloody usefull it is too. It could be made to look a lot nicer but I cannot be bothered,,,
Similar story here with a section of heavy gauge channel, and various big lumps of steel acquired over the years in various shapes. None look pretty, but very handy.
 

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