Sheet metal flat patterns

[JoeM]

I have to say it again.  Why is the sheet metal functionality left glaringly incomplete?! I've been using TurboCad since V4, and I've gotten every upgrade since V8.

When the bend tool was introduced in V14, I thought the next release would be the one.  Well, unbend was introduced in V15, but without bendlines or convenient creation of a 2D flat pattern.  Surely the programmers were in the middle of completing this functionality, but didn't have it ready in time.  The next release would be the one. Not so.  After V16 was released, with no useful improvements for sheet metal work, IMSIDesign hinted that this would be a priority for the next release.  I bit the bullet and paid for the upgrade again.  Each time I bought these upgrades, I thought, "If I don't get it, it will just cost me more next time".  Now V17 is out, and lacks this functionality. At this point, I'm feeling as if I've been strung along.

I can't just keep buying upgrades because someday IMSIDesign might get around to doing something that would be helpful.

Maybe they could partner with a sheet metal software company to provide a stripped down version of unfold software that works with .SAT files for a few hundred dollars?  But I doubt if they could do that for less cost than if they simply finished what they started within TurboCad.

Frustrated,

JoeM

[Jeffin90620]

I agree.

I work with small aerospace companies that usually form their cases from bent aluminum.  The ability to (accurately) unfold/unbend a 3D case into a flat pattern with the necessary markings for fabrication is something any real-world Mechanical CAD software should be able to do.

As I have posted in another thread TurboCAD doesn't even unfold/unbend accurately.  This can be fatal for small companies on a limited budget.


Jeff

[dgapilot]

I also agree. I've been waiting to upgrade until this functionality is there. Since 17 doesn't have it, why should I pay the price when I can get 15 pro mechanical on ebay for about $250 and have the same function. If I'm going to pay the almost $1500, the unbend needs to have bend lines shown so a true flat plate drawing can be made

[marc_256]

@JoeM

I also agree with you.

Marc

[Glenn]

Now I'm abit bummed that TurboCad dose not unfold sheetmetal.
I work for a motorhome company who has just bought turbocad and when I looked through the book and saw that you could fold sheet metal I assumed that I would be able to unfold boxes and send the files straight to our sheetmetal workers.

I hope this is something that they do as an addon.

Cheers Glenn

[dgapilot]

Glen,
The unfold used to be part of the Mechanical edition in 15 & 16. In 17, it's part of Platinum Edition. The drawback is that when it unfolds, you don't get set back or bend lines on the drawing. Seems they haven't made any changes to the unfold command since it was originally put in back in v15. Now 2 versions later, still no fix for an issue that has been known ever since it was introduced.

[Henry Hubich]

Pending the incorporation of this feature in TCad, I've been trying to develop a practical workaround for its absence. Attached screenshot illustrates a successful application of the workaround: bending the flat pattern along the lines located in accordance with my technique results in an exact re-creation of the original object. I intend to post a brief description of the procedure in a day or two, but be warned that it's a LOT more cumbersome than a properly equipped "Unbend Sheet" TurboCAD tool would be.

Henry H

[Don Cheke]

Pending the incorporation of this feature in TCad, I've been trying to develop a practical workaround for its absence. Attached screenshot illustrates a successful application of the workaround: bending the flat pattern along the lines located in accordance with my technique results in an exact re-creation of the original object. I intend to post a brief description of the procedure in a day or two, but be warned that it's a LOT more cumbersome than a properly equipped "Unbend Sheet" TurboCAD tool would be.

Henry H

Beautifully done Henry!

[T. Karlmann]

I have just done a small sheet metal bending project, and have also found Unbend not to work.  TC should please fix this.

ALSO:  It would be nice to be able to control where the bend goes for Flanges!  It's always the most difficult thing is to make a "U" shaped part where both sides of the U fit to a known specification.  Flange cannot do this.  I had to make my flanges, cut the part, skew each half over and add them back together.  Let's have the same options for flanges that we have for bending things.

[Henry Hubich]

I have just done a small sheet metal bending project, and have also found Unbend not to work.  TC should please fix this.

In v17, I've found that Unbend works pretty well, provided one caters to its limitations (which seem less severe in v17 than in earlier versions).


ALSO:  It would be nice to be able to control where the bend goes for Flanges!  It's always the most difficult thing is to make a "U" shaped part where both sides of the U fit to a known specification.  Flange cannot do this.  I had to make my flanges, cut the part, skew each half over and add them back together.  Let's have the same options for flanges that we have for bending things.

The Flange tool is certainly awkward. Since the bend line is always at the edge of the part, the only way to control its location is to modify the part before flanging. I've found the Facet Editor and Quick Pull both useful for this purpose.

Henry H

[T. Karlmann]

I have just done a small sheet metal bending project, and have also found Unbend not to work.  TC should please fix this.

In v17, I've found that Unbend works pretty well, provided one caters to its limitations (which seem less severe in v17 than in earlier versions).


ALSO:  It would be nice to be able to control where the bend goes for Flanges!  It's always the most difficult thing is to make a "U" shaped part where both sides of the U fit to a known specification.  Flange cannot do this.  I had to make my flanges, cut the part, skew each half over and add them back together.  Let's have the same options for flanges that we have for bending things.

The Flange tool is certainly awkward. Since the bend line is always at the edge of the part, the only way to control its location is to modify the part before flanging. I've found the Facet Editor and Quick Pull both useful for this purpose.

Henry H

Just to elaborate on the flange tool, why not (also) simply have a RELATIVE number when making the flange width?  Those absolute numbers there become gibberish for my applications.  I had to make an approximate flange, Slice it off, then Facet Edit to a known line length to get the flange to the proper width.  (Length was ok)  Then add it back on.

[cmsrobert1]

With reference to the initial thread: TCAD seems to be aimed at Architects. Us mech  engineers get left with the add-ons.
An example is architectural rendering looks superb but try it with detailed mechanical items and it can not handle it and often crashes even with v17.2 and a quad core dual proc pc. All the materials are aimed at architects, no sheet metal, mesh, checker plate etc in the lists. The thread tool add-on is good for bolts and holes but what about nuts, washers springs etc -common use items.
I design large machines with hydraulics etc. To get tc to render (even in hidden line) I have to simplify (take out detailed items) most of the items which is so time consuming. These detailed items are useful as I use the rendered pictures  in operators manuals etc. Currently I have to settle for sections of basic drawings that do not show everything and therefore look less realistic to the reader. It would be great to be able to assemble the finished product/machine with the components and not have it crash or have to alter the assemblies to avoid it crashing.

[Jeffin90620]

I design large machines with hydraulics etc. To get tc to render (even in hidden line) I have to simplify (take out detailed items) most of the items which is so time consuming.

I don't know for certain that this would work but you could try converting everything from Solid to Surface before rendering.  I haven't done a lot of detailed renderings, but it seems to me that the memory requirements would drop significantly.

Just remember to save your Surface drawing under a new name and return to the Solid drawing for editing.

Jeff

[Jaffa]

May I add myself to the above list of frustrated folk.

I upgraded to Platinum Pro in the belief that it had the tools I needed for designing in sheet metal. I mean, the video made it look so easy? (I know better now.)

Following a frustrating weekend my CAD expert friend and I concluded that the bend and unbend tools are so flawed that they are virtually useless. For the record - the unbend tool should accept a 3D model contstructed from solids, joined, filleted with appropriate bend radii and then accurately flat-state it. The bend tool should be capable of bending this flat state into an identical copy of the original. The existing tools do not do this and should not be capable of passing a Software Engineering QA until they do.

Surely we are not asking for the impossible here?

[Jeffin90620]

I am so unhappy with the Bend tools that I only use the Flange tools.  With ACIS History turned on, I can easily adjust items to meet up.

Except for the two wires going off screen (those are rail sweeps), every bend you see is a Tube Flange, and every one of them was edited for length, angle and azimuth to fit as required.

Jeff

[Henry Hubich]

May I add myself to the above list of frustrated folk.

I upgraded to Platinum Pro in the belief that it had the tools I needed for designing in sheet metal. I mean, the video made it look so easy? (I know better now.)

Following a frustrating weekend my CAD expert friend and I concluded that the bend and unbend tools are so flawed that they are virtually useless. For the record - the unbend tool should accept a 3D model contstructed from solids, joined, filleted with appropriate bend radii and then accurately flat-state it. The bend tool should be capable of bending this flat state into an identical copy of the original. The existing tools do not do this and should not be capable of passing a Software Engineering QA until they do.

Surely we are not asking for the impossible here?

The tools will do these things, but one must be careful to maintain uniform material thickness in the bent regions. Have a look at my post dated May 23, 2010 (above).

Henry H

[dgapilot]

So we have a couple work arounds but so far nothing direct within turbocad for bend lines. Did IMSI do anything in Ver 18 to address this issue, or is it still the same? There is nothing on the Turbocad web site to indicate that the functionality has improved. Until it does, I'll stick with what I've got. The unbend with bend lines and set back are a must for spending any more $ on an upgraded Turbocad.

[Henry Hubich]

So we have a couple work arounds but so far nothing direct within turbocad for bend lines. Did IMSI do anything in Ver 18 to address this issue, or is it still the same? There is nothing on the Turbocad web site to indicate that the functionality has improved. Until it does, I'll stick with what I've got. The unbend with bend lines and set back are a must for spending any more $ on an upgraded Turbocad.

v18.0 does not address this issue :-(

Henry H

[dgapilot]

Doesn't IMSI even look at this forum? The sheet metal tools first showed up in v14, here we are at v18 and there is no improvement in the functionality. I agree with others that the archatechtural tools seem to be quite good, while the mechanical tools leave a lot to be desired.

TURBOCAD (IMSI) engineeres and software designers PLEASE give us tools that make our job easier.

[sjh_498@yahoo.com]

Has anyone tried using the projection function on the bend to create the bend line?  Make sure it is based on the flat pattern edge.  Then when you move the bent part aside the line can be used as the neutral axis and you can define the flat pattern.  I haven't made a drawing yet but now I can view it whereas before I couldn't view the bend line or IS/OS Rad

[Henry Hubich]

Has anyone tried using the projection function on the bend to create the bend line?  Make sure it is based on the flat pattern edge.  Then when you move the bent part aside the line can be used as the neutral axis and you can define the flat pattern.  I haven't made a drawing yet but now I can view it whereas before I couldn't view the bend line or IS/OS Rad

Can you elaborate a bit? I don't quite understand.

Henry H

[kmartin]

Me either. I am not sure how this would work. 

[Dean]

Has anyone tried using the projection function on the bend to create the bend line?  Make sure it is based on the flat pattern edge.  Then when you move the bent part aside the line can be used as the neutral axis and you can define the flat pattern.  I haven't made a drawing yet but now I can view it whereas before I couldn't view the bend line or IS/OS Rad

Can you elaborate a bit? I don't quite understand.

Henry H

Perhaps it is in reference to un-fold face.  Henry, can I ask you a question , Everyone is talking about the bend line not being projected onto the un-bend sheet is this correct? Is not this in reference to a neutral axis/ which is just an arbitrary calculated imaginary line, no? Bend lines can be calculated then placed. I do not  fully understand what the issue is with the bend tool. If you have the time could you please described to me in layman's terms. I am not a sheet metal specialist just trying to follow. Is the possible flaw in the calculation of the neutral axis  being transferred to the un-bend sheet or simply that the bend line is not being placed on the un-bend sheet. how did you accomplish what you created above?

[Henry Hubich]

 Henry, can I ask you a question , Everyone is talking about the bend line not being projected onto the un-bend sheet is this correct? Is not this in reference to a neutral axis/ which is just an arbitrary calculated imaginary line, no?

Neutral axis is an entirely different entity from bend line. When a ductile material, such as mild steel sheet, is bent, the region on the outside of the bend undergoes elongation (stretching) while the region on the inside is compressed. Someplace inside the material itself -- not far from halfway through the thickness but often not exactly there -- is an infinitely thin layer that is neither elongated nor compressed. This layer is located at what we call the "neutral axis" (even though axis may not be the most accurate terminology). The amount of elongation/compression experienced by any given thin layer is directly proportional to its distance from the neutral axis. When creating a flat pattern intended to be bent into a specified shape, it is necessary to know the depth of the neutral axis in order to calculate how much material to allow for the bent regions.

A bend line is simply a line drawn on the flat pattern to indicate where to make the bend. To make a simple part, I often clamp the flat pattern in a vise with the bend line even with the top of the jaws, and then whack the thing with a plastic mallet. You can see from this example that the concept is a bit ambiguous: I have to be aware of which side of the pattern gets clamped -- the part to the right of the bend line or the part to the left -- and which side gets whacked.

Is the possible flaw in the calculation of the neutral axis  being transferred to the un-bend sheet or simply that the bend line is not being placed on the un-bend sheet.

That's it: No bend line.

How did you accomplish what you created above?

I started with the 3D part and unbent it. That's easy. Bending the resulting flat pattern to re-create the 3D part is difficult, awkward, time-consuming, error-prone, and a PITA with the current state of TurboCAD.

Henry H

[Dean]

Thanks Henry,I am starting to grasp it. I work primarily with wood. Understanding the tools and workarounds in Tcad and how they function is rewarding and useful.In the picture below I un-folded the faces of the two flat flanges and outside radius then placed them on the workplane of the un-bended sheet. Would those lines where they meet be the bend lines,give or take a little. Is this where the neutral depth measurement comes into play? I see how changing the neutral depth changes the measurment of the flat flange thusly changing the bend line,no?

[Henry Hubich]

Thanks Henry,I am starting to grasp it. I work primarily with wood. Understanding the tools and workarounds in Tcad and how they function is rewarding and useful.In the picture below I un-folded the faces of the two flat flanges and outside radius then placed them on the workplane of the un-bended sheet. Would those lines where they meet be the bend lines,give or take a little. Is this where the neutral depth measurement comes into play? I see how changing the neutral depth changes the measurment of the flat flange thusly changing the bend line,no?

Pretty close. Actually, the neutral depth measurement changes the measurement of the material in the bent region. If you had been able to un-fold a radius located inside the material (at the neutral axis, specifically) rather than the outside radius, then when you placed the three cross-hatched items end to end they would exactly match the un-bended sheet.

The program usually sets the Neutral depth at half the material thickness, by default. (The depth is measured from the inside of the bend.) That's a reasonable approximation when the bend radius is several times the thickness, but for tighter bends a somewhat smaller value is more likely to be correct.

Henry H

[Dean]

" If you had been able to un-fold a radius located inside the material (at the neutral axis, specifically) rather than the outside radius, then when you placed the three cross-hatched items end to end they would exactly match the un-bended sheet."

You know Henry,it is funny you say this because when I initially placed the un-folded face of the outside radius onto the workplane of the un-bended sheet (format place on workplane) it was acutually down a tad into the unfolded face(placed on workplane) top edge of the bottom flat flange. I moved it up to line up with the top edge of the flat flange  thinking it was just a glitch or perhaps when I moved the un bended sheet I moved its Z axis.

[Henry Hubich]

" If you had been able to un-fold a radius located inside the material (at the neutral axis, specifically) rather than the outside radius, then when you placed the three cross-hatched items end to end they would exactly match the un-bended sheet."

You know Henry,it is funny you say this because when I initially placed the un-folded face of the outside radius onto the workplane of the un-bended sheet (format place on workplane) it was acutually down a tad into the unfolded face(placed on workplane) top edge of the bottom flat flange. I moved it up to line up with the top edge of the flat flange  thinking it was just a glitch or perhaps when I moved the un bended sheet I moved its Z axis.

I really think that's the most likely explanation.

Henry H

[JoeM]

I just wanted to bump this thread to the top of the list - hoping that IMSI won't forget about sheet metal for the next release.

JoeM

[Henry Hubich]

Re-bump ;-)

Henry H

[bwolfe]

Confirm  bump and re-bump.  8-)

Brock

[dgapilot]

Bump Bump Bump