Grundsau Posted June 4, 2014 Share Posted June 4, 2014 Am using a P5 fly press to form drip cups/pans for candleholders. I cut off the top piece of a gas cylinder valve protector for a top die and a swage block acts as the bottom die. Normally a rounding hammer is used on a sheet metal blank with the swage block. Does anyone know how to avoid the wrinkled edges when lowering the top die onto the blank? The sheet metal blank in the photo was formed in the smaller depression and the top die was too big to fit it's diameter. Some other blanks, not pictured, were wrinkled even more when they were placed in the larger depressions. Quote Link to comment Share on other sites More sharing options...
the iron dwarf Posted June 4, 2014 Share Posted June 4, 2014 try it with discs rather than squares and thicker material is easier, also a shallower dish my work better Quote Link to comment Share on other sites More sharing options...
Crazy Ivan Posted June 4, 2014 Share Posted June 4, 2014 We do something similar on a larger scale at my work (250 ton press brake and 1/4" SS) and the top die is only slightly smaller then the bottom die and has the same curvature as the bottom die. I know its quite a huge scale difference but the shape of your top die may be a factor in the wrinkles due to the "slop" between dies. Maybe try finding/making a top die that matches the bottom a bit better? They may fit just fine and its just the picture making me think that. Also, as Dwarf said, thin sheet metal likes to wrinkle when formed without much stretch/shrinking and discs may work out best. Maybe see if you have the same problem with 16 ga or whatever size is the next size up from what you were using (if what you are making still looks okay with thicker steel). Hope this helps. -Crazy Ivan Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted June 4, 2014 Share Posted June 4, 2014 Greetings Grund, It depends on the material and the size.. If you are going into production you will need closer stock control and better dies.. If you are only making a few you can use a smaller die on top and a wood block.. Either start with trimmed rounded stock.. What you are asking the stock to do is compress and stretch at the same time.. Hot works better.. Press on and make beautiful things Jim Quote Link to comment Share on other sites More sharing options...
njanvilman Posted June 5, 2014 Share Posted June 5, 2014 You might need to anneal the material before forming, depending on what material you are forming. Quote Link to comment Share on other sites More sharing options...
E.F. Thumann Posted June 5, 2014 Share Posted June 5, 2014 Jim, did you machine the knurled punch holder? Or get it from someone/etc? What's the advantage vs using the tooling hole in the ram? Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted June 5, 2014 Share Posted June 5, 2014 Greetings GF, I have many many tool holders for my flypress ... That one I did not make .. It was made by a fine machinist that sells them on E Bay.. The reason I use that one is it has a 3/4 receiver and I use planishing hammer dies for the top... My P6 has a 1 in hole .. The dies work great for upper tooling.. Forge on and make beautiful things Jim Quote Link to comment Share on other sites More sharing options...
tsterling Posted June 6, 2014 Share Posted June 6, 2014 In my press forming adventures I always get those wrinkes. I stop pressing before the wrinkles get too convoluted and hammer them flat on the anvil, anneal the sheet, and then press again. Rinse, lather, repeat as required. My pressing is lots smaller than yours, but the same principles are at work. Here's a link to the beginning of a long tutorial on my method of press forming: http://sterlingsculptures.com/wp/?p=2143 Good luck! Tom Quote Link to comment Share on other sites More sharing options...
Grundsau Posted June 16, 2014 Author Share Posted June 16, 2014 Thanks for all the good info. Will try discs and not press them as far the next time. In my second photo showing the small depression in the larger square piece, I'm going to make a smaller square that is slightly larger than the depression and then knock the corners down after forming. Might look interesting with a tapered candle. Quote Link to comment Share on other sites More sharing options...
arftist Posted July 6, 2014 Share Posted July 6, 2014 Thanks for all the good info. Will try discs and not press them as far the next time. In my second photo showing the small depression in the larger square piece, I'm going to make a smaller square that is slightly larger than the depression and then knock the corners down after forming. Might look interesting with a tapered candle. http://thelibraryofmanufacturing.com/rubberforming.html Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 7, 2014 Share Posted July 7, 2014 Pressing a male die into a female die is closed die forming and a different thing. The clearance between the male and female should be the thickness of the stock being formed. You want to take it all the way in one hit or work hardening will become a bear quickly. If you're top die is what you want you might try using it to make your bottom die by simply driving it into a piece of HOT steel till it's there. Then you can develop the clearance by first rough forming a piece of steel the thickness you want to form parts from and driving it into the HOT bottom die. Yeah, that's kind of iffy but it will work if you're persistent enough. Okay, luck might. . . MIGHT come into it too. <grin> Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Alan Evans Posted August 2, 2014 Share Posted August 2, 2014 Am using a P5 fly press to form drip cups/pans for candleholders. I cut off the top piece of a gas cylinder valve protector for a top die and a swage block acts as the bottom die. Normally a rounding hammer is used on a sheet metal blank with the swage block. Does anyone know how to avoid the wrinkled edges when lowering the top die onto the blank? The sheet metal blank in the photo was formed in the smaller depression and the top die was too big to fit it's diameter. Some other blanks, not pictured, were wrinkled even more when they were placed in the larger depressions.image.jpgimage.jpgOpening up and old thread, but did you sort your problem? Have a look back to May 2013 the bowl tool making thread, there are a couple of videos I made for someone else which may help. Do you want to form a flat square with a dish in the middle or form the whole square into a bowl or are you going to cut the round bowl after forming? Either way your problem is that the tools are not a pair. If there is no gap out on the perimeter between the top and bottom tool the work piece does not have anywhere to go and so does not buckle. Use your current top tool to form a thicker dish from a disk of say 6mm or 10mm (1/4" or 3/8") or thicker in to your swage block so that they fit one another, you can use chumps of round or slide the swage block off centre in order to achieve the radius you are after. If it's the radius of your top tool you want to retain the same applies push a thicker disk into the swage block or a ring with your top tool, soften it's edge and leave it there and use that as your bottom tool. As far as process goes...with thin sheet especially stop trying to do it in one hit in the centre... resist the temptation! Start from the rim and work in towards the centre...have a look at the videos I mentioned...even if you are wishing to form the version with the square flange and dimple, form the complete bowl first by going round and round the outside first then flatten the flange down afterwards. You can do this without changing tools by resting the bowl on a ring and resting a plate on top and then pressing...alternatively turn the bowl over on a plate resting on the swage block and push a ring down onto it.. Good luck, Alan Quote Link to comment Share on other sites More sharing options...
ianinsa Posted August 2, 2014 Share Posted August 2, 2014 Sounds like you might have done it before Alan! Ok , ok I saw the pictures(moving) so it did happen.Ian Quote Link to comment Share on other sites More sharing options...
Alan Evans Posted August 3, 2014 Share Posted August 3, 2014 Sounds like you might have done it before Alan! Ok , ok I saw the pictures(moving) so it did happen. Ian Ha! Hi Ian, once or twice! Much the same info as others have posted but "a picture is worth a 1000 words a demo is worth a 1000 pictures…" I don't seem to be able to edit the post above but if anybody is about to look at the videos, when you get bored of the demo fast forward to the last minute or so which has some more interesting bowl shapes triangles and rectangles… I noticed from the Youtube log that most people only watch the first couple of minutes, must edit the video down... Alan Quote Link to comment Share on other sites More sharing options...
Grundsau Posted August 5, 2014 Author Share Posted August 5, 2014 Thanks Arftist and Frosty. Alan, I stepped back from the problem for awhile due to other commitments. Watched your very informative vids. I'd like to work rounds and squares in different configurations and will keep at it. Thanks Quote Link to comment Share on other sites More sharing options...
Dodge Posted August 16, 2014 Share Posted August 16, 2014 Grundsau, Where I used to work (light pole manufacturing) we pressed base plate covers from a single sheet of 14 or 16 ga steel. The sheet started as an octagon about the size of a stop sign. (in fact that's what we called these blanks). There was a special die set that, with the aid of a 60 ton press, would form these stop signs into rounded cornered "tub" (the new nick name after the pressing process) about 6" deep x 10 - 12" square that had a flange that we cut off later. That flange was what was not formed into the die much like the OP's photo except they were flat. What those top and bottom dies had were "lands" for lack of a better word that pressed the edges of the stop signs flat as the dies came together. Perhaps if you were to weld a flat land around your top die that would meet the flat surface of you swage block at the same time as the top round die bottomed out it would also flatten the outer "flange". I don't know if this muddies the waters or not but after re-reading Alan's post I suspect that is sort of what he was suggesting. The "lands" leave nowhere for the outer square to go but flat. A side note; the sides of our flanges were not straight anymore due to the amount of material being drawn into the die on the sides as opposed to the corners. Also the reason for them being octagons. (less material to flatten; a square sheet of that thin of material, even with the lands would surely buckle at the corners) The drawing is crude but hopefully you see what I mean Hope this was helpful Scott Quote Link to comment Share on other sites More sharing options...
Alan Evans Posted August 18, 2014 Share Posted August 18, 2014 Grundsau, There was a special die set that, Snip... after re-reading Alan's post I suspect that is sort of what he was suggesting. Hope this was helpful Scott Any info is helpful! :) In this case however it is not what I was suggesting. My system is far simpler/cruder and less specific. The advantage of mine however is that you could make the dimpled flanged vessels in a variety of sizes, rather than just the one which your special die set were made for. My tools will not do it in one push, which is where they fail if you are wanting a production efficiency. It is versatility versus speed I guess. Using my tools the dimple/bowl curve would always be the same radius, or shallower depending whether you bottom out with the tools. You do need a dedicated ring or length of tube for each lip-of-bowl to flat-flange (size of dimple) diameter you required. Each time you would start from the outer edge of your workpiece blank and form all of it to the bowl curve. And then flatten out the flange using the ring/length of tube and pushing the bowl onto a bit of flat plate as a secondary process. With a little bit of practice tweaking they should be wrinkle free. Hope that makes sense... Alan Scruffy sketch showing stages:- Quote Link to comment Share on other sites More sharing options...
Grundsau Posted October 30, 2014 Author Share Posted October 30, 2014 Fall has been busy with getting our honeybees ready for winter, taking portraits and artisan shows starting up I will get to this again and thank you for the additional info. 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.