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Seastar
05-26-2013, 01:22 PM
I bought a very old Fisher anvil, probably made in the 1800's.
It was very cheap but the edges are badly chiped.
The face is OK so I thought I might bolt it in the mill and take a cut down each side to clean it up.
Problem is the face is very hard and I'm not sure how to mill it.
Would carbide work? The chipped edges would make an interrupted cut at first
How would you clean it up?
Bill

lazlo
05-26-2013, 01:28 PM
A lot of smiths will just clean up the surfaces with a big flap wheel on an angle grinder. My blacksmithing instructor does this on the ACC anvils once a semester after the students have dinged them up.

I've seen people mill the surfaces if it has a bad swayback. The top surface is in the low 50's (unless it's a Refflinghaus), so it's no problem with a carbide tool.

Alistair Hosie
05-26-2013, 05:02 PM
I bought an old one recently not too big but a heavy devil none the less around 250 ,pounds anyway it was repaired at the end with a proper job with dowels and welded well together it was though cheap and cheerfull only costing me 30 plus diesel however I did trim the top up and smoothed out the weld with a flap grinder dusty job it was too.I am happy with it and can say the flap wheel does a good job.I actually trim wood with this method also when doing rustic work it works great. Alistair

J. R. Williams
05-26-2013, 05:30 PM
Many of the old anvils had a top plate forge welded on the anvil. It was a piece of cast steel and would be very hard. With proper pre-heating you might be able to build up the edge with some hard surfacing rod and grind it back to shape.

spongerich
05-27-2013, 10:33 AM
I'd probably fashion some sort of temporary guide fence and smooth it with an angle grinder. Once it's fairly smooth, then you could take a finishing cut with a carbide cutter.

lazlo
05-27-2013, 01:39 PM
With proper pre-heating you might be able to build up the edge with some hard surfacing rod and grind it back to shape.

I've seen several folks try that, never with success -- the hard face always pops off. There's a huge amount of thermal mass in the anvil, so preheating it is a bitch.

adatesman
05-27-2013, 03:55 PM
When I asked about refinishing my Fisher a while back I was advised to simply touch it up with a belt sander and flap wheel since the edges are supposed to be radiused anyway and gouges can be worked around or prove useful at times. YYMV.

alsinaj
05-27-2013, 06:34 PM
This may sound dumb, but faced with the problem of making one of the soft Horror Freight anvils usable, I faced off the anvil, bought a piece of pre-hardened 1/2" tool steel plate, cut and ground it to fit, and epoxied it to the freshly-faced and thoroughly cleaned surface. If I wanted to, I could probably knock the plate off by striking it from the side, so I'm careful not to do that. The surface isn't as hard and bouncy as a real anvil, but with care, I've been able to do the occasional small forging job with it. The top is still secure after several years.

ironmonger
05-27-2013, 07:50 PM
Fisher anvils were made by preheating a steel 'top', inserting it into the mold and casting iron in the mold and thus welding the top to the body.

see:
http://www.anvilfire.com/21centbs/anvils/fisher-norris.php

but to address your concern about the edges...

The hard sharp edges that the anvil had when it was new are not that useful for forging. If I need a sharp edge I'll use a top plate or a butcher.
Not to many places in forging for a sharp 90 degree corner. The various radii that can be ground onto the edges are more useful.

One forging technique is half on half off, where the stock to be forged is placed on the edge of the anvil and is struck by a hammer face that is held half over the face and half off. Any drawing action (where the stock is made longer at the expense of cross section) needs to be done with at least one curved face to make the metal move perpendicular to the axis of the stock instead of spreading out like a cowpie if it were struck full on the anvil with a the full face of a flat hammer.

I didn't mean to launch into a mini forging lesson, but suffice to say the the soft edges are much more useful then a a knife edge. It may look pretty through machinist eyes, but the smith's eyes would look for a more useful soft edge....

paul

Seastar
05-28-2013, 01:43 PM
I ground off some of the chips but have a way to go to have an even edge.
Looks like it will take some more work.
It will be ok when I get it ground down.
Bill

http://imageshack.us/a/img69/4282/imageoth.jpg (http://imageshack.us/photo/my-images/69/imageoth.jpg/)

lazlo
05-28-2013, 06:08 PM
The edge don't look terrible, but that's a heck of a hollow in the center. I'd fly cut it...

Seastar
05-28-2013, 06:32 PM
It's really flat in the center within a few thousands . I think that is a shadow in the picture.
Bill

vpt
05-28-2013, 09:41 PM
Personally I would just leave it. If you make it all perfect and nice when you chip it you will be upset.

lakeside53
05-28-2013, 11:03 PM
Here's mine - about 100lb. Metalmagpie found it for me.

http://i238.photobucket.com/albums/ff150/lakeside53/misc%20linked%20uploads/DSC_3577Custom_zps4f80849d.jpg
http://i238.photobucket.com/albums/ff150/lakeside53/misc%20linked%20uploads/DSC_3578Custom_zps1166389f.jpg
http://i238.photobucket.com/albums/ff150/lakeside53/misc%20linked%20uploads/DSC_3579Custom_zps6b180bec.jpg
http://i238.photobucket.com/albums/ff150/lakeside53/misc%20linked%20uploads/DSC_3580Custom_zps86c5aea3.jpg


Similar to that discussed -it has a steel plate cast into the top surface. I was going to "fix" it, but now you guys have me worried.

Seastar
05-29-2013, 10:23 AM
I'll trade you,
Yours is a lot better than mine.
Bill

Seastar
05-29-2013, 10:27 AM
On second thought I think I'll just keep it.
It works OK so I am going to leave it as is.
I have started a knife blade------
Thanks for all the input.
Bill

ironmonger
05-29-2013, 10:32 AM
All those little nicks and chips can be ground smooth and even the chip in corner of the face of the last example might find some use.

The blacksmith forums are littered with face re-weld stories, some successful and others not so much. As with welding any medium carbon or higher steel preheating and post weld heat treatment is a good idea. There is a running debate regarding hard-face rods vs whatever... bear in mind that HOT steel is softer and does not require a R50 anvil face to make the anvil useful.

If you need a SHARP 90 corner for a forging project it is easier to weld a stem on a block of 1045 that fits in the hardy hole and have your edge.
You can also fashion a steel plate that covers the face of the anvil and is secured to the anvil through the hardie hole with a tapered key or a bolted hold-down. This plate can also supply a sharp corner if desired... you will soon wonder what the sharp corner is good for other than cutting off stock.
The large 'flat surface of an anvil has uses even if it is slightly concave. It can then be used to straiten a bent piece. The slight concave surface keeps you from applying to much 'correction'.

My rule of thumb is an anvil is to weigh 50 to 100 times what your hammer weighs. Not to say that you can't vary from there, but the larger the mass is the more stable the anvil is... better to have only one of the two, that is hammer and anvil, surface moving about. Forging can be a difficult dance without everything moving at once. For gosh sakes fasten the anvil to the stand with out welding... looped chains or forged brackets work just fine. The stand needs to be SOLID as well. Don't support your 200# anvil with a rickety network of 2X4's or 3/4" bedframe angle iron. It's not supposed to be easy to move...

The other relationship between how much flat face you need is based on he size of the work. If you are forging to a width of 2" it is senseless to have a perfectly flat surface 6" square. The work happens between your hammer face, maybe 1-1/2" around or square, and the big flat thing. :>)

If you have a seriously swaybacked anvil you might be better served heating a 3/4" thick plate or so, forging it into intimate contact with he sway-backed face, and then facing than off with your fly cutter.

*rant off*

paul

lazlo
05-29-2013, 10:53 PM
Andy, those Vulcans are neat - they have a muted ring (and bounce) compared to a conventionally constructed anvil.

Seastar: you'd be surprised how much those edges will clean up with a little work on a flap wheel, but if the top is flat, leaving it alone works too :)

Working on a swayback anvil is a major PITA -- nothing is flat or straight when you're done. At least for, me anyway :rolleyes:

Seastar
05-30-2013, 02:10 PM
I needed a stand for my old anvil and tree stumps are hard to find here in the city.
There are dozens of stumps in my wood pile at my cabin in Minnesota but that's 850 miles from here.

So I scrounged in my wood pile and found some blocks of oak and some 8'-2x6"s.
After a little sawing, screwing and glueing this ugly thing evolved.
Perfect height and very solid though.

http://imageshack.us/a/img577/3519/imageomzf.jpg (http://imageshack.us/photo/my-images/577/imageomzf.jpg/)


Bill