ausfire

Hofi repair

Recommended Posts

Got a problem with my favourite Hofi hammer. It never hits anything cold, but it's developed a bad nick on one corner and a crack extending down the face. It's not impossible that I could have hit the anvil at some stage, but I can't recall having done so.

So do I grind it back, keeping it cool, or what? I don't want to make it worse! It's a very comfortable hammer and I use it a lot. Also quite expensive when you take into account freight from Germany. I would like to rescue it.

hofi nick 2.JPG

hofi nick.JPG

Share this post


Link to post
Share on other sites

Can you include a photo of the Hofi logo, and other markings, usually on the side of the hammer?  This will help determine if your hammer is forged or cast.

Share this post


Link to post
Share on other sites

Either way I see a narrower hammer face in your future.  Unless you can get some kind of warranty replacement you will need to grind that crack out.  The crack will most likely continue to run, so I would address it before using the hammer further.  I have made similar "repairs" to a Swedish style MOB hammer that I got at a flea market by grinding around 1/4" off the width of the face on each side.  Definitely keep it cool while grinding.

It looks like the initial crack was made by dropping the hammer face on that corner onto a hard surface (concrete floor?).  It is hard to tell from the photo, but it is possible the head was not correctly normalized and the grain structure a little chunky.  Or perhaps Hofi hammers have particularly hard faces.  I drop hammers in my shop pretty regularly, but maybe I've been lucky.  Of course the only Czech style hammers I have are custom made (mostly by me), so YMMV.

Share this post


Link to post
Share on other sites

Glenn, the only marking on the hammer is the logo as in the first picture above. I can read the word HOFI, but not sure what the other hieroglyphic is.

Latticino, I don't think the hammer has been dropped, and the floor of my work forge is soft. As you say, I think it will be a smaller HOFI in the future. A bit disappointing, as it was really nice to use. Well balanced.  

Share this post


Link to post
Share on other sites

Is the Hofi logo formed into the metal (as in stamped in) or does it stand out as in being on the mold when cast?

Share this post


Link to post
Share on other sites

Appears to be stamped in the photo.  I would expect this is a forged hammer head.

Share this post


Link to post
Share on other sites

No matter the cause, you have a problem. 

Either its under warranty or you have a repair to do. 

grind the face down until the crack is gone, then file out the sharp edges on the corner crack. 

You may have to take the face down to the bottom of the chip in the first pic. This may mean you will need to re-heat treat the face. 

With a bit of luck, the crack is not deep and you will only need to dress the corner chip.

Share this post


Link to post
Share on other sites

Have you contacted Uri?

Frosty The Lucky.

Share this post


Link to post
Share on other sites

I had an anvil dropped soft wrought iron horn first onto an "industrial" concrete floor.  No damage to the anvil horn and a noticeable divot in the the concrete.  I don't think a hammer would suffer damage with a much less force involved floor impact.   My "guess" would be heavy impact with a hard faced anvil.  Perhaps in very cold weather too when some alloys are more brittle.

I would contact Hofi; the chip is user error, the crack is of concern.

Share this post


Link to post
Share on other sites
19 hours ago, ThomasPowers said:

I would contact Hofi; the chip is user error, the crack is of concern.

I don't have a contact for him. I bought the hammer a few years ago from a place in Germany, but I didn't keep a record of the transaction. I guess I will try repairing it by grinding and keeping it as cool a possible. I am reluctant to take it right down to the base of the chip, as I have no idea how to heat treat these things, and would probably make it worse.

Perhaps if I took it to an engineer who could resurface it?? You wouldn't do that to an anvil, but maybe the hardness/structure/density or whatever is different for a hammer. I don't know enough about the science, but I do know it is (or was) a comfortable, ergonomically designed tool.

Or maybe I should pension it off to a hook on the wall, and seek a replacement. :(

Share this post


Link to post
Share on other sites

As I mentioned, I would thin the width, not grind the face off.  Of course you would lose the stamps, but less of the hardened face.  Each to his own.

Share this post


Link to post
Share on other sites

As a customer nearly half way around the world, and before you start grinding and so forth, I would make a concerted effort to contact Hofi, show photos and see if you could get a replacement.  It's not going to be a financial burden on Hofi to replace one hammer from a dedicated customer.  I would use a substitute hammer until you hopefully get a response, if any, from Hofi.  You seem to be very attached to the Hofi hammer and I would think he would be honored to have someone willing to go to those lengths to have it replaced.  Good luck getting the issue resolved.

Share this post


Link to post
Share on other sites

I'm not usually an emotional person but when I saw that chip & crack it brought tears to my eyes. I had the same response when the handle on my favorite cross peen that was handed down to me by my grandfather broke & had to be replaced.

BTW... just sent you a PM.

Randy

Share this post


Link to post
Share on other sites

I met an old farrier/blacksmith in the Gunnison valley. Every time I was in the area I stopped by and we "hunkered down" for a bit. He gave me a round faced crosspeen he had made. A few years later I was using it and a crack developed in the crosspeen. A few weeks later or so, I learned he was forging lightning bolts in the sky. Turns out his passing was the day the crack materialized. 

Ive always wondered if their was a connection. 

I still use the hammer, but not the peen end.

 

Share this post


Link to post
Share on other sites

Iron dragon, I hope you saved the hammer pieces to make scales for a knife!

Share this post


Link to post
Share on other sites

Thanks for the PM, Randy. I have contacted Mr Hofi.

I showed the hammer to an mechanical engineer today. He said the crack doesn't look too deep, but maybe I should have been more observant, and corrected that before the chip came out. He said it could be machined back, but it would upset the balance of the hammer.

I guess the crosspeen end is still functional.

Share this post


Link to post
Share on other sites

If your bent on repairing, you could probably have it gouged, then tig it back in. If done properly it shouldn't seriously affect it. This isn't a garage deal tho, to properly weld the alloy steel it should be preheated, and then reheat treated after welding. A tool and die shop could probably fix fairly well if you don't want to remove the affected material/alter the hammer geometry.

Share this post


Link to post
Share on other sites

Reading a little more in the sticky about the hofi hammer, he mentions he used C45 for the forged hammers, which to me sounds like a 1045 carbon steel. Really nothing to special about it. If it was welded with an appropriate medium carbon filler at the appropriate heat treat, annealed well, and the reheat treated, it probably wouldn't be worse for the wear.

Or if your feeling really adventurous, you could take off a known amount to remove the crack. And then forge weld on a new face. Beyond my skill, but should be possible.

Share this post


Link to post
Share on other sites

To me it appears to be a forged hammer and the chip and crack are superficial and not past the hardened area. 

Depending how you feel about doing this, you can grind the crack out, fill the crack in with stick rod and heat treat. 

My guess is that the heat treatment made it that little bit too hard to tolerate a cold blow to the anvil. 

Classic proof that hammers shouldn't be that hard. Have a scar on my left forearm as reminder. 

It will become your favourite repaired hammer. :)

Share this post


Link to post
Share on other sites

Thanks Marc and Chuck. Interesting information, but beyond my skill and confidence level. I have emailed Hofi (thanks Randy) but the email was undeliverable. Anyone have a more recent email address? I just thought he may be able to suggest what repair could happen. If no response I'll just give it to an industrial blacksmith and see what they can do. In the meantime, my $15 club hammer from Bunnings is doing OK.

Share this post


Link to post
Share on other sites

Well, I was unable to contact Mr Hofi for advice on repairing the hammer, so I decided to get another one, this time from America. I found a company on the net operating from Amarillo, TX and ordered a 2.4# Hofi-style hammer from them. It arrived yesterday and I gave it a trial run today - seems OK. It's a bit lighter than the original damaged one but seems well balanced and comfortable. I thought the price was reasonable at US$126, but as always the freight to Australia was expensive at US$114.

The old one is all but useless apart from the cross pein end, so I have given it to a local engineer/welder to rebuild. A couple of pics of the damaged one and the newy:

 

new hofi 2.JPG

new hofi 3.JPG

new hofi1.JPG

Share this post


Link to post
Share on other sites

OK, so our local welder removed the cracked section and welded in a new piece. I reckon he did a superb job, and the hammer is now back in use. Here's a picture of the repair:

 

DSC_0752.JPG

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.