Jura T

Going to blue with your tempering can actually be bad for impact strength, depending on the alloy you are using. Have a look on temper embrittlement:

http://steel.keytometals.com/articles/art102.htm

Great video, thanks. Hadn't seen that earlier. I was more or less sure that they would have used sen in the old days, and that confirms it.

  

 

I finally managed to find a Japanese video on the whole process. They use a bench grinder to hollow the backs (www.youtube.com/watch?v=6bI_q1gksII, see 18:50). Embedding the video seems to make the the post dissappear...

  

 

I do the final sharpening of my chisels with waterstones. When taking the back of the chisel (not the whole back but part nearest to the edge) to mirror finish I find that I can do it faster and easier with Japanese chisel (hollow backs) than with western chisels (flat back). I haven't noticed any problems using Japanese chisels for example for tenons.

Well, as Davis wrote it is a lot easier to lap the bottom when it is hollow. Sometimes when I've restored old chisels, I've ground the center hollow to make the lapping faster. Partially it is just the challenge to make Japanese chisels  

I haven't found any videos, despite quite extensive search.

 

Why do you do it after heat treat? I tried doing it with a fuller, but it is difficult to get good looking results. I guess I finally need to get a proper belt grinder.  

Hi,

How would you hollow a back of a chisel as seen f.e. over here:

  

Those ones seem to be ground. Any idea what is used for the narrow grooves in production runs? I'm planning to do a set or two, so speed and consistency would be required...

The BBC iPlayer seems to work only if you are in the UK.

Happy Birthday Brian!

There used to be a Blueprint on that...

You can find photos and CAD drawings in the thread over here: http://www.shopfloor...ead.php?t=12464

I've been thinking of making one of those, however I'll probably make a Hossfeld type of bender: http://www.bbssystem...lbender_102.pdf

MOBlacksmith, I've seen an anvil that was bolted to a concrete block with thin rubber mat in between. I didn't ring at all. I didn't forge on it so I can't say anything about the bounce. I guess, I'll try the silicon, especially as I should have a tube of silicon lying around somewhere. Thanks for the hint.

Daniel, the No 58 is more or less a standard model for Refflinghaus. They seem to have it in stock most of the time. It took a week and a half from the order to get it.

I opened the package yesterday, there were no animals in it. There was a Ernst Refflinghaus No 58 150 kg anvil, the one I've been lusting for for ages. What a surprise! :)

I didn't have much time to forge yesterday, just enough to make a quick hot cut hardy and to finish the axe I started making last weekend. The anvil definitely feels a lot more solid than my old one (85 kg). Now I just need to mount it properly on the stump and to put some rubber mat in between them to deaden the ringing.

Was it labled "Fragile, Handle with care" :P

Naturally. I was shocked to notice that they had not put any shock sensors on it. :P

The delivery guy just brought me a package. I wonder what's in it? :D

Great film!

Mark Pearce shows in one of the UMBA DVD library dvds (RD70) how to make a horse head with a mane. He curls the mane which I think gives a nice finish. Below is my attempt on something similar.

It is getting late here, but I couldn't wait until tomorrow. So I took a piece of 2x4 hit the ledge with it as hard I could. That helped, the box came loose (and the gasket stayed in good shape).

The loose bolt is bent quite a bit. If I heat and straighten it, does it need to be heat treated? Or should I make a new one? The head might be a bit of an challenge as I don't have a metal lathe. The angle on the head is about 40 degrees.

The guide block seems to be seated/shimmed with some hard black stuff. I guess I need to scrape that of and get some shims.

Stick a 2 X 4 down from the top and hit it.

I already tried that. Although I didn't go full force, as I wasn't quite sure if the ledge was part of the frame or the sleeve. After seeing some Anyang cross-section pictures, I'm pretty sure that it is part of the sleeve. I'll hit harder tomorrow.

Thanks John.

I removed the nuts holding the bottom sleeve. The sleeve seems to sit in really tight. When I look into the air chamber form the top there is a ledge (which I assume is part of the bottom sleeve?) and on the side of it there is an air port. When feeling the surfaces (rough cast surfaces) inside the air port, I cannot feel any seam between the sleeve and the frame, so there probably is a very tight fit. I guess I have to build some sort of frame on top of the cylinder to jack the sleeve out. Any ideas for that?

Put some jointing paste behind the guide blocks as they can loose a suprising amount of air down the back.

I don't know what jointing paste/pipe dope is, so could someone give a product name for a global brand (Sikaflex for example)?

Today one of the first things I planned to do at the shop was to punch an eye to a tool with my power hammer (40 years old russian air hammer). I already had my foot on the treadle, but I wanted to start with a good single blow. So I raised my foot and stepped on the treadle again, that sent the the ram right up and there it stayed. I noticed the other of the guides (I'm not quite sure if they are called guides) was hanging slightly low (see the first picture). So I took the top cover of and jacked the tup up with a bottle jack. There are two bolts holding a guide. It seems that the upper bolt had freed itself and the piston hit it on the way down. I can feel that the bolt is loose and one side of it has a bent on it. I guess that I have to take the lower part of the cylinder off to access the nut...

Now that I'm disassembling cylinder+piston part I have two questions. First of I noticed that the piston rings are placed so that they all have the open part in the same place. Is there a reason for that, or should I rotate them into different positions? Now is also a good time to check the clearence between the tup and the guides. So, what is correct clearance for that?

The answer is simple-i've stepped too far outside of my experience and capability,have challenged meself too steeply.

But stepping out of one's comfort zone is where the learning happens. Now you know more about your capabilities.

Good job on the candle holder. I'm glad you showed all the steps and problems making it. It helps all of us to learn.

A bolster plate is a plate with holes of different sizes (and shapes) in it.

Beth, I used 16mm round for the center. I used a power hammer tenon tool (http://www.iforgeiro...679-tenon-tool/) to take the stem to 6mm. Then I domed and decorated it on a bolster plate.

Jake, I also really like the shape of that piece (and most of the others John posted). I usually like more contemporary forge work, but that piece caught my eye. Nice organic scrolls and that flower makes it different from more regular scrolls.

I was ready to put this project on hold, but decided to give it a last try today. I'm glad I did as it turned out fairly good. The flower is just a quick mockup to see how it would look like finished.

I would tend to agree with you about the cracks in the material. Probably too hot too often, no evidence of burning, but just below that point I would think.

Getting too hot too often was the only reason I came up with. It is quite frustrating as I was paying special attention to only heat the welded area to welding heat. I took 2-3 welding heats per welding, just to make sure that I got good welds and to take all the seams out. I guess I could shoot for 1-2 welding heats.

What section of material are you using? It looks to be a squarish section as opposed to a flat rectangular section.

I guess it is hard too see from the photo but it is rectangular. I'm starting with 8mmx12mm and then take it down to about 6mmx12mm at the thicker parts (I also have forged a taper at the pierced end). Following your suggestion in leaving more material for welding definitely helped a lot.

I'm not too worried about shapes/flow as I concentration more on the welding part. Especially, after seeing the cracks I only made the shapes close enough. I think I'll try the flatter to smooth the transitions next time.

I would also suspect that the originals (because of the quantities involved) were made to scrolling jigs.

I have also thought about using jigs. That way it would probably be easier to get lines right around the welded branches as the material is thicker there.

It isn't easy trying to get mild steel to perform like wrought iron, they are after all two entirely different matarials and have their own characteristics and peculiarities. (But it's fun trying to get the same appearance.)

It would nice to make the same piece out of wrought iron just for comparison.

Thanks again John!