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Ed Caffrey's Workshop Talk to Ed Caffrey ... The Montana Bladesmith! Tips, tricks and more from an ABS Mastersmith. |
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#1
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accordian fold angle
G'day Ed It was a great pleasure to meet you at the Blade show> I have just made my first 2 mosaic billets and have accordian cut one of them and flattened it out, made it 3/8 thick and got a tear in it as I went, thats ok as I have weded it shut. Is there a particular angle that should be used ie; 45 degrees? I have straightened the fold on the horn of my anvil as I do not have a press just yet, and man what a job that was, any tips would be great Cheers Keith
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#2
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Hi Keith!
I really don't believe that any specific angle is better than another. The most important part of an accordion fold is that equal thickness needs to be maintained, especially through the "hinges", and equally important is to make sure that both the inside and outside areas of "V" cuts are radiused out. The biggest issue with the accordion fold is the "V"s......the inside of the cut experiences tremendous expansion, while the outside of the cut experiences tremendous compression.....all that taking place within 3/8" or less. Actually. come to think of it, a wider angle cut will reduce the stresses, but can be detrimental to the patttern. I do know that the greater the angle of the "V" cuts, the more dead space you will see between the mirror images of the patter going down the billet....the less the angle, the less dead space you will see between the mirror images. It basically boils down to a trade-off. Which always seems to be the case when dealing with mosaics. __________________ WWW.CAFFREYKNIVES.NET Caffreyknives@gmail.com "Every CHOICE has a CONSEQUENCE, and all your CONSEQUENCES are a result of your CHOICES." |
#3
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Cheers for that Ed. Thats what I thought just didn't know if I was being to greedy with the angle that I cut it on, really don't like to chop out to much material.Thanks again
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#4
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Hey mate,
Dont be afraid to cut out big bits. We will be able to fill a can up quicker that way Cheers Bruce __________________ Barnett Custom Knives-Australia www.barnettcustomknives.com Australian Knifemakers Guild Sec/Treas American Bladesmith Society Apprentice |
#5
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I've found that if I use welding temps with some flux to protect it from decarb and open it slowly I didnt get any tearing.
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#6
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Thanks for that Bruce, I did open it up at welding temp and I did it slow I did not put any flux on it but I will next time, thanks for the tip, it did not tear at the hinge but on the 4 way weld I did previously but right at the hinge it worked out ok as I was able to reweld it once I had the bar flat, I guess because the horn of the anvil is tapered it would cause more stress on one side of the fold to the other and that may have caused the tear, I'll just have to get that press. Cheers again Keith
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#7
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Quote:
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#8
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Hi Bruce no I have not tried the tile method as yet, from what I have read you need to lay the tiles on a sacrificial piece of steel, weld it then grind or mill the piece off. Is there more chance of getting carburisation in the welds between all the tiles using this method? Run me through the method you use.
Cheers Keith |
#9
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Keith, you can see what has worked for me dealing with tiles here http://www.knifenetwork.com/forum/sh...ad.php?t=44311
Good luck .. Matt |
#10
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Keith there is a way to do this without using a sacrificial piece as you call it. The method was delveloped by Tom Ferry as far as I know. the proceedure goes as follows. Make you bar of mosaic as you normally would for an accordian lets say it is 1 1/2 by 1 1/2. Now decide wich way you want your pattern to show and mark the sides that you would normally cut the notches in. Put it back in the fire and flatten the the bar on the sides that you marked so that you have a bar that is 1 1/2 by 3/4. Now clean up the scale and grind the bar smooth the flatter and smoother the better. Now mark the bar across the narrow side in forty five degree angles 3/4 inches apart and saw it into pieces. Keep the pieces in order and oriented the way that they came off of the bar. lay all of the pieces down on the bench just like they were still a bar. Now starting at one end pull the pieces apart one at a time and flip it so that the pattern is now facing up. do this for all the pieces that you have and slide them all together so that they represent what will be your new bar. make sure the pattern is lined up and all the bevels fit togehter kind of like this \\\\\\\\\\\\ when viewed from the side. now weld the all together with a mig or tig welder. weld all the way anround each joint and then grind off all the excess weld bead so that you once again have a smooth bar. Make sure that you have a 100 percent tight weld around each joint. Now heat and weld in the forge. make sure that you soak at welding heat until you are absolutely sure that it is at welding heat and let it soak at least a half hour longer. You don't have to use a whole lot of heat 2350 is more than hot enough. weld and draw the bar out to nearly twice it's length. this should leave you a bar that is 3/8ths of an inch thick and a inch and a half wide by whatever length you have. now grind it down on both sides until there is no trace of the welding rod or wire that was used with the electric welder and forge whatever knife shape you desire. piece of cake right? this is called the Ferry flip.
__________________ Bill Burke ABS Master Smith 2008 |
#11
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Yea, what Bill said.
Thanks Bill, I couldnt have said it better. I should copy this thread |
#12
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Thanks Matt, Bruce and Bill. Yeah Mate that does sound like a piece of cake LOL. Well there is only one way and thats to try it out and I will do that in the next few days and I will let you all know how I get on. Bill I have been trying to send you an email but it just keeps coming back send me an email so I have a link. Thanks again all for your help.
Cheers Keith |
#13
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Quote:
Keith I sent you one about a week ago, I guess It didn't get through. Try sending me one to: Bill Burke at blade Gallery dot com. put this in standard e mail format ie.. **@**.com. Also the Ferry flip works the best with a rolling mill, press or hammer. I don't remember if you told me that you had one of these. I think that it would be a real bugger(pain in the a**) to do by hand. I wish I was there with you (in the winter where it's cool) to help out. __________________ Bill Burke ABS Master Smith 2008 |
#14
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Burke,
I admit to not being the brightest bulb in the chandelier but could you help me out with the Ferry Flip (please use small words). I can't seem to visualize how the vertical (end of the bar) pattern gets turned horizontal (length of the bar) with this method Seems to me if you squash down on a square billet until it's half it's previous height but still the same width all you would get is a distorted version of the original pattern still on the end of the bar. Then you say cut it into tiles at an angle, flip it over and reweld it - isn't that the same as simply flipping it over without cutting it? Obviously, I'm not reading something correctly or I'm missing some critical point. I'd really like to know how this works... |
#15
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I'm sitting here smiling because I know how to do it, and am waiting to see how Bill explains this in words. I tried it a couple of times and finally gave up.
I've always been envious of how Tom's mind works.....when it come to thinking things out, he has a gift, and the first time he explained the process to me, I had the "Dog at the TV screen look" on my face. He finally got it through to me. In the process the relationship of what Tom calls "pre-distortion", and the final width of the billet are critical and directly related. For what Bill is describing, a 1 1/2" square mosaic billet is flattened one way to 3/4", while maintaining the 1 1/2" width, then the tiles are cut, "dry welded", and the billet is draw to 1/4" thick. Draw the billet thicker or thinner and the pattern becomes distorted. Its all about figuring out how much "pre-distortion" to employ, in a given width, to obtain an NON-distorted pattern when completed. See! I told you, trying to explain it in words is HARD! GO BILLY! GO BILLY!!! __________________ WWW.CAFFREYKNIVES.NET Caffreyknives@gmail.com "Every CHOICE has a CONSEQUENCE, and all your CONSEQUENCES are a result of your CHOICES." |
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