Bill Tillman Posted May 31, 2011 Posted May 31, 2011 (edited) I have a hat section brake shape that I want to extrude along a taper. But so far when I try to do this I don't get the results that I want. When I chose EXT, then "T" for taper and put in the anlgle of 9° and a length of 12, I get a very short piece which tapers in the wrong plane. Any sheet metal guys out there who can offer advice? LOFT created a less than desirable results as well. SectionAA.pdf Edited June 1, 2011 by Bill Tillman Quote
Jack_O'neill Posted June 1, 2011 Posted June 1, 2011 I'm no sheet metal expert, but you could do it in 3 pieces. The flat mid section could be one piec, with the brim of the hat being two other pieces. Then union them and fillet the edges. Quote
Jack_O'neill Posted June 1, 2011 Posted June 1, 2011 (edited) something like unto this: Note: It occurred to me that I didn't make any fuss over the angle, just eyeballed something and ran with it. sheetmetal.dwg Edited June 1, 2011 by Jack_O'neill Quote
nestly Posted June 1, 2011 Posted June 1, 2011 You'd have to make sure you're extruding in the right direction, but I'm still not sure you'd get the result you want. Perhaps draw the top and bottom sections and use LOFT? http://screencast.com/t/u5XokjGl Quote
Bill Tillman Posted June 1, 2011 Author Posted June 1, 2011 I tried several methods including putting this together in pieces and I got what I wanted. The actual part is more complex than this model and using this piece part method I got a really nicer 3D model. But that was rather a complicated process of doing UNIONS, FILLETEDGE, SLICE, SUBTRACT, etc... So I thought I try and find out about using LOFT. But as you can see what happened in this process the bottom ended up being shaped more like a ships hull than the straight line appearance the part will become. NESTLY: That was a really cool video. How'd you do that? In any case, your LOFT process seem to have got the part like I want it. I did a simple LOFT using a section from each end but the bottom did not come out as planned and I got more of a transitional surface than a straight edge like I need. ISO(01).pdf Quote
Jack_O'neill Posted June 1, 2011 Posted June 1, 2011 I tried several methods including putting this together in pieces and I got what I wanted. The actual part is more complex than this model and using this piece part method I got a really nicer 3D model. But that was rather a complicated process of doing UNIONS, FILLETEDGE, SLICE, SUBTRACT, etc... So I thought I try and find out about using LOFT. But as you can see what happened in this process the bottom ended up being shaped more like a ships hull than the straight line appearance the part will become. NESTLY: That was a really cool video. How'd you do that? In any case, your LOFT process seem to have got the part like I want it. I did a simple LOFT using a section from each end but the bottom did not come out as planned and I got more of a transitional surface than a straight edge like I need. I drew the flat bottom bit first and extruded it. Then one of the "L" shaped sides. Copied that and aligned them to the edges of the base. Unioned the three of them, filleted the edges, then put an extruded rectangle at each end to subtract from the bent shape giving the straight edges. That's the only way I could get the crisp angles that a box break would make. My loft attempt looked much like yours, with a bend starting at each corner and blending out in the middle somewhere. Nestly does make some cool videos, doesn't he? I look around in the forum sometimes just to see what he's come up with next. Quote
Bill Tillman Posted June 1, 2011 Author Posted June 1, 2011 Yes, indeed. I want to learn how to make videos like that for myself. But I tried the LOFT operation he showed in it, the 2nd one, and the part still ends up with the bottom looking like a ship's hull. I guess I gotta study more about LOFT settings, although in the video it did not show any changes to the LOFT command that I saw. Quote
Bill Tillman Posted June 1, 2011 Author Posted June 1, 2011 (edited) What option are you using for LOFT? Nothing. I'm just telling it to use the two sections I have drawn and then hit Enter. The two sections I created are PEDIT and REGION'ed and I separate them 12" apart in the Z axis. The bottoms of them line up and I then run the LOFT command. OKAY Here's the update to this. When I did this with the sections just being a polyline and not REGIONS, it worked like I wanted it to. I would not have thought that about the REGION command. I'll have to make a note of this. The LOFT method required a few steps but it was still easier and less work than putting all the pieces together separately. And it gave some of the parts I needed to repeat already drawn after I did some SLICING and then UNION it back together. Edited June 1, 2011 by Bill Tillman Quote
nestly Posted June 1, 2011 Posted June 1, 2011 I believe the reason your LOFT doesn't look like mine is because you have extra vertices in the polyline. That makes more sense now that I see your complete part. I would probably break it up and draw a section at each step in your part, then loft them separately, then join them together. As for the videos, it's really quite easy (and Free) Jing is a basic screen capture program from the Techsmith, (the makers of Camtasia Studio) that easily captures whatever happens on your screen as either a screencap, or a video, and automatically uploads it to free storage area they give you at screencast.com Quote
Jack_O'neill Posted June 2, 2011 Posted June 2, 2011 As for the videos, it's really quite easy (and Free) Jing is a basic screen capture program from the Techsmith, (the makers of Camtasia Studio) that easily captures whatever happens on your screen as either a screencap, or a video, and automatically uploads it to free storage area they give you at screencast.com[/i] I've tried using Jing a few times after you told me about it some time ago, but I don't know if its just that my processor isn't up to the task or what. They come out really jerky and poor quality to watch. This thing is beginning to get a bit long in the tooth, but it works for what I need most. Quote
Bill Tillman Posted June 2, 2011 Author Posted June 2, 2011 Here is the finished product. Coming soon to the under carriage of large snow plow rigs in the NE United States. Now, I've been told that Inventor will unfold this to make the sheet metal layouts needed for the CNC guys. Is that a true statement? Quote
kencaz Posted June 2, 2011 Posted June 2, 2011 Here is the finished product. Coming soon to the under carriage of large snow plow rigs in the NE United States. Now, I've been told that Inventor will unfold this to make the sheet metal layouts needed for the CNC guys. Is that a true statement? Yes, It can be done in a matter of minutes in Inventor complete with flat pattern: KC Quote
Bill Tillman Posted June 2, 2011 Author Posted June 2, 2011 Yes, It can be done in a matter of minutes in Inventor complete with flat pattern: [ATTACH]27950[/ATTACH] [ATTACH]27951[/ATTACH] KC Does it take into account the bending (stretching) allowances for the various thickness of metal? Quote
kencaz Posted June 2, 2011 Posted June 2, 2011 Does it take into account the bending (stretching) allowances for the various thickness of metal? Yes, Inventor is very good at configuring the kfactor and corner reliefs according to your materials thickness. Quote
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