poundhound Posted July 9, 2011 Share Posted July 9, 2011 Hello all, I am new to the forum and blacksmithing as well. I have been attempting a few projects but keep running into the same problem of when I punch a hole then expand it, it tends to go off to one side or the other. does anyone have any tips or techniques I can read up on to keep the hole inline with the rest of the work, I know I have to try to punch the first hole as close to center as possible. here are some pictures to show the problem. easier to see in dog picture then railroad spike any help appreciated. poundhound Quote Link to comment Share on other sites More sharing options...
brianbrazealblacksmith Posted July 9, 2011 Share Posted July 9, 2011 You have already evaluated your problem and understand it, so you know you need equal amount of material on both sides of your slot. Your choice of punch can help with your ability to find and maintain your center. Try using a slot punch like I describe in "Slitter Geometry" for punching thin stock. It is not a flat punch. It is ground differently than any other punches I have seen, and it can enable you to lay out your mark at the black heats and change angles like you can with a center punch before you make your deep forging marks. Flat punches will not allow that because they can only make double marks because of the greater surface area contact. Quote Link to comment Share on other sites More sharing options...
Marksnagel Posted July 9, 2011 Share Posted July 9, 2011 Brian is one of the most knowledgable people in the business. Are you starting your hole with a slit prior to using a round punch? I would also pay attention to your heat. Keep it even. If one side of the piece that you want to punch is hotter than the other side, then the steel will be softer on that side and thus give easier to the punch causing an uneven hole.I know this from experience. Watch your heat. Mark <>< Quote Link to comment Share on other sites More sharing options...
David Einhorn Posted July 9, 2011 Share Posted July 9, 2011 A couple thoughts come to mind: 1) Is the side that expanded the most the same side that was pointed down into the fire. If one side is hotter than the other side, then that side will stretch more when a drift is inserted to widen the hole. Keeping both sides equally hot will ease keeping the hole centered. 2) Once off-center you can straighten it by heating, then placing the ring over the horn of the anvil or over the end of a cone, and then tapping the side that you wish to move over towards center. After it is straight, then tap the end to an oval and flatten the little nib that will result in the round hole becoming an oval bottle opener. Always straighten prior to proceeding to *each* next step. Quote Link to comment Share on other sites More sharing options...
peacock Posted July 9, 2011 Share Posted July 9, 2011 When you first see that the hole is off center, take a heat then cool the thin side in water before you drift it. As you drift the hot side will stretch and the cold side will not. With a little experence you will be able to recenter the hole. Clifften Ralph showed me this one. Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 9, 2011 Author Share Posted July 9, 2011 thank you all for the excellent suggestions I will try to incorporate them into my next piece. I do start with a split hole, I will try to make it cleaner and send a picture to make sure I am doing it correctly pound hound Quote Link to comment Share on other sites More sharing options...
Marksnagel Posted July 9, 2011 Share Posted July 9, 2011 Oh heck I forgot! Welcome to IFI. All questions will be answered in the order that they are stumbled across. Mark <>< Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 10, 2011 Author Share Posted July 10, 2011 thanks for the welcome! after reading more of the threads on Slitting and drifting and Slitting Geometry, I think I am using the wrong shape punch (?) to start the slit (sorry I am not at home to post pictures). I should use a thinner one. seems like the flat bottom type would work, but the V shape seems to have some advantages. I will make one of each and see what works better. Poundhound Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 10, 2011 Share Posted July 10, 2011 Welcome aboard Pound Pound glad to have ya. If you put your general location in your header I'm sure there're lots of IFI guys who'll be more than happy to stop buy for lunch and a little forge time. Looks like you're doing decent work as a beginner, tips and practice will bring you along just fine. Brian is really good at most everything so I'm just going to read and re-read his posts, not to mention trying to get ready for his classes here at the end of the month. Frosty the Lucky Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 11, 2011 Author Share Posted July 11, 2011 Tried different punches last night although ran into problems of the tabs not coming out cleanly. any suggestions as to why this would happen. do the punches have too sharp a tip? is it technique? should I try to make a v shaped punch? does one type of punch punch better then others? on the plus side, I was able to make pretty centered holes with about 3 heats (about 1 inch round in 1 inch x 1/4 inch material) which seemed reasonable. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 11, 2011 Share Posted July 11, 2011 Punches for making holes shouldn't have a point at all, they should be pretty flat with clean edges. I punch till I heel the anfil and this does NOT mean the punch is making contact with the anvil, just the resistance. Then I turn the piece over and place the punch on the dark spot made by the punch and anvil drawing the heat out of the thinned steel at the punch site, and punch the slug out. A bolster is good and takes less practice but the method is pretty much the same. Punching crooked holes is most likely operator error, the most common I see are, not holding the punch vertical, Not striking inline with the punch, being too enthusiastic with the hammer making the work jump and cocking the punch. If you use a center punch it'll drift the hole as you punch it. It'll be a lot more work and unless you want a drifted hole it's not appropriate. Before I developed my skills set enough I'd come up with all sorts of tools and jigs to keep punches aligned properly. The best helper I came up with is was something to rest my tool hand knuckles on to help keep the punch vertical. Once it was started the hole did the trick. It wasn't a good solution as I learned out of needing it quickly by practicing. Frosty the Lucky Quote Link to comment Share on other sites More sharing options...
MattBower Posted July 11, 2011 Share Posted July 11, 2011 Frosty, I think he's looking at Brian Brazeal's slitter geometry thread. Brian's slitters are sort of pointy slot punches. That's where he's getting that idea. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 11, 2011 Share Posted July 11, 2011 Frosty, I think he's looking at Brian Brazeal's slitter geometry thread. Brian's slitters are sort of pointy slot punches. That's where he's getting that idea. Yeah, you're probably right, I forget newcomers may not know the difference between a punch and a slitter. Mia culpa. Frosty the Lucky Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 11, 2011 Author Share Posted July 11, 2011 Yeah, you're probably right, I forget newcomers may not know the difference between a punch and a slitter. Mia culpa. Frosty the Lucky that is exactly correct what is the difference between a punch and a splitter, and why would I use one or the other for making a hole? Also what is a bolster? sorry for the dumb questions. PoundHound Quote Link to comment Share on other sites More sharing options...
John B Posted July 11, 2011 Share Posted July 11, 2011 that is exactly correct what is the difference between a punch and a splitter, and why would I use one or the other for making a hole? Also what is a bolster? sorry for the dumb questions. PoundHound Not a dumb question, just an answer not yet found. Put simply, A punch shears its way through the workpiece, and a slug or pellet the size of the tool's tip being used is produced. A Drift can then be put through the orifice produced, and an accurate sized hole/slot (round or square or other shape eg as an eye on an axe or hammer) can be produced. A Splitting chisel has a finer point and works more like pushing a blade into an item and forcing the structure apart, rather than shearing its way through, a drift or other manipulation (jumping up)is used to finish to the required profile. A slotting punch will produce a slug, a slitter may not, depending on how the tip is finished A bolster is a backing/support used to prevent the punches or slitters being gripped when the tool is struck and the metal deforms particularly if it is not supported adequately swage blocks are large bolster plates, for slitting, a narrow slot slightly wider than the tool is used, they can easily be made by bending a wide bar on edge and closing it parallel the width plus a slight clearance of the tool being used, Looks like an elongated U Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 11, 2011 Author Share Posted July 11, 2011 Not a dumb question, just an answer not yet found. Put simply, A punch shears its way through the workpiece, and a slug or pellet the size of the tool's tip being used is produced. A Drift can then be put through the orifice produced, and an accurate sized hole/slot (round or square or other shape eg as an eye on an axe or hammer) can be produced. A Splitting chisel has a finer point and works more like pushing a blade into an item and forcing the structure apart, rather than shearing its way through, a drift or other manipulation (jumping up)is used to finish to the required profile. A slotting punch will produce a slug, a slitter may not, depending on how the tip is finished A bolster is a backing/support used to prevent the punches or slitters being gripped when the tool is struck and the metal deforms particularly if it is not supported adequately swage blocks are large bolster plates, for slitting, a narrow slot slightly wider than the tool is used, they can easily be made by bending a wide bar on edge and closing it parallel the width plus a slight clearance of the tool being used, Looks like an elongated U thank you that explanation helps a lot. But why would I choose to use a splitter vs a punch? Does the type of hole differ when drifted if one or the other is used? PoundHound Quote Link to comment Share on other sites More sharing options...
John B Posted July 11, 2011 Share Posted July 11, 2011 thank you that explanation helps a lot. But why would I choose to use a splitter vs a punch? Does the type of hole differ when drifted if one or the other is used? PoundHound Consider this, You can use a splitter and produce a 2" diameter hole in a 1" wide bar and leave a 1/2"(approx) rim around the hole See where this is going? Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 11, 2011 Author Share Posted July 11, 2011 Consider this, You can use a splitter and produce a 2" diameter hole in a 1" wide bar and leave a 1/2"(approx) rim around the hole See where this is going? that makes sense for the splitter, since it is leaving 1/2 inch of the one inch material on each side of the hole. however in the "splitting geometry" thread brian posted a picture of a horse bottle opener he punched out the hole, but the ring around the hole was much smaller then the origial material left. is that due to starting with a punch, or because he futher worked the metal and thined it out?horse opener on this page part way down posted at Posted 02 April 2009 - 01:11 PM just trying to figure things out. PoundHound Quote Link to comment Share on other sites More sharing options...
MattBower Posted July 11, 2011 Share Posted July 11, 2011 He slit that, then worked it around a mandrel of some sort, maybe the horn of the anvil. Slitting leaves more material to work with. (I call it slitting; some say splitting.) Quote Link to comment Share on other sites More sharing options...
brianbrazealblacksmith Posted July 12, 2011 Share Posted July 12, 2011 thank you that explanation helps a lot. But why would I choose to use a splitter vs a punch? Does the type of hole differ when drifted if one or the other is used? PoundHound A punch shears the sides of the hole, so the interior sides of the hole are more like a drilled hole [no matter what the shape: round, square, oval,slot,...], so when you drift the hole, the drift enters more efficiently. When you chisel the hole with a slitter, you get a more beveled hole witch is alot more resistant to a drift that is used to open up the hole to the desired shape. A chisel or slitting chisel only works when the material is backed or supported. The books say to chisel or slit 3/4 or 2/3 through the material and then turn it over and chisel or slit the rest of the way. Without backing or support a chisel or slitter cannot cut the material. It only stretches it until it can stretch no more and then finally pierces it.[metal is very resistant to stretching] That is why you will always see cold shuts in thicker metal that has been done with a chisel and slightly stretched metal when done on thinner stock. Punches solve this problem, and the punches shown in "Slitter Geometry" are much more efficient than flat punches because of the surface area contact with the material. I had Karen take a video of how I use a slot punch for thin stock, and here it is. If I had the technology to film the difference between chisels, flat punches, and these punches, anyone could see the difference. It is self evident. I know it is not conventional knowledge because it has not been written down yet in a book, but just try it and you will see for yourself. http://www.youtube.com/user/brianbrazealblacksmi Quote Link to comment Share on other sites More sharing options...
MattBower Posted July 12, 2011 Share Posted July 12, 2011 A punch shears the sides of the hole, so the interior sides of the hole are more like a drilled hole [no matter what the shape: round, square, oval,slot,...], so when you drift the hole, the drift enters more efficiently. When you chisel the hole with a slitter, you get a more beveled hole witch is alot more resistant to a drift that is used to open up the hole to the desired shape. A chisel or slitting chisel only works when the material is backed or supported. The books say to chisel or slit 3/4 or 2/3 through the material and then turn it over and chisel or slit the rest of the way. Without backing or support a chisel or slitter cannot cut the material. It only stretches it until it can stretch no more and then finally pierces it.[metal is very resistant to stretching] That is why you will always see cold shuts in thicker metal that has been done with a chisel and slightly stretched metal when done on thinner stock. Punches solve this problem, and the punches shown in "Slitter Geometry" are much more efficient than flat punches because of the surface area contact with the material. I had Karen take a video of how I use a slot punch for thin stock, and here it is. If I had the technology to film the difference between chisels, flat punches, and these punches, anyone could see the difference. It is self evident. I know it is not conventional knowledge because it has not been written down yet in a book, but just try it and you will see for yourself. http://www.youtube.com/user/brianbrazealblacksmi Thanks, Brian. That's very educational. Quote Link to comment Share on other sites More sharing options...
brianbrazealblacksmith Posted July 12, 2011 Share Posted July 12, 2011 You're welcome Matt. I'm sorry that wasn't the best video, but we just got that I-pad and we're still trying to figure it out. Quote Link to comment Share on other sites More sharing options...
MattBower Posted July 12, 2011 Share Posted July 12, 2011 A punch shears the sides of the hole, so the interior sides of the hole are more like a drilled hole [no matter what the shape: round, square, oval,slot,...], so when you drift the hole, the drift enters more efficiently. When you chisel the hole with a slitter, you get a more beveled hole witch is alot more resistant to a drift that is used to open up the hole to the desired shape. A chisel or slitting chisel only works when the material is backed or supported. The books say to chisel or slit 3/4 or 2/3 through the material and then turn it over and chisel or slit the rest of the way. Without backing or support a chisel or slitter cannot cut the material. It only stretches it until it can stretch no more and then finally pierces it.[metal is very resistant to stretching] That is why you will always see cold shuts in thicker metal that has been done with a chisel and slightly stretched metal when done on thinner stock. Punches solve this problem, and the punches shown in "Slitter Geometry" are much more efficient than flat punches because of the surface area contact with the material. I had Karen take a video of how I use a slot punch for thin stock, and here it is. If I had the technology to film the difference between chisels, flat punches, and these punches, anyone could see the difference. It is self evident. I know it is not conventional knowledge because it has not been written down yet in a book, but just try it and you will see for yourself. http://www.youtube.com/user/brianbrazealblacksmi Thanks, Brian. That's very educational. I know you're right about the cold shuts, because I've slit a couple hammer heads and that happened to both of them. I didn't understand why until I read your explanation. Quote Link to comment Share on other sites More sharing options...
brianbrazealblacksmith Posted July 12, 2011 Share Posted July 12, 2011 Every hammer that has been done that way with a slitting chisel will always have cold shuts. That is just the way it is. I have done it also, and that is why I do it no more. Quote Link to comment Share on other sites More sharing options...
poundhound Posted July 12, 2011 Author Share Posted July 12, 2011 A punch shears the sides of the hole, so the interior sides of the hole are more like a drilled hole [no matter what the shape: round, square, oval,slot,...], so when you drift the hole, the drift enters more efficiently. When you chisel the hole with a slitter, you get a more beveled hole witch is alot more resistant to a drift that is used to open up the hole to the desired shape. A chisel or slitting chisel only works when the material is backed or supported. The books say to chisel or slit 3/4 or 2/3 through the material and then turn it over and chisel or slit the rest of the way. Without backing or support a chisel or slitter cannot cut the material. It only stretches it until it can stretch no more and then finally pierces it.[metal is very resistant to stretching] That is why you will always see cold shuts in thicker metal that has been done with a chisel and slightly stretched metal when done on thinner stock. Punches solve this problem, and the punches shown in "Slitter Geometry" are much more efficient than flat punches because of the surface area contact with the material. I had Karen take a video of how I use a slot punch for thin stock, and here it is. If I had the technology to film the difference between chisels, flat punches, and these punches, anyone could see the difference. It is self evident. I know it is not conventional knowledge because it has not been written down yet in a book, but just try it and you will see for yourself. http://www.youtube.com/user/brianbrazealblacksmi Brian thank you for the great explanation and video, it really makes sense now. I will have to make myself some punches like you describe. esp seeing how you originally set the location of the punch site by marking then the sequence with you go through to punch out the tab. thanks again PoundHound Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.