In this dwg I have been building a 3D curved fillet in a corner where two flanges meet. I use a special method to make this to ensure the fillet follows the radii of the adjacent flanges in the perpendicular planes, which share a common magnitude of radius. This kind of fillet occurs when the sheetmetal worker drills out the corner of the Alclad sheet and then bends the flanges. It reduces the possibility of cracking in the corner.
Okay, thanks to Cj7hawk I have been able to move forward with my trial of the CorelCAD software. Kudos to you Cj7hawk.
With this particular drawing, if you take the SE Isometric, you will see I built a 3D solid fillet in the corner of the two flanges, and unioned this to the plate. As far as I can tell, it follows the views and stays in the same place.
The second fillet was made the same way and in NE isometric it looks right. But it will not union. In fact there is a message when you try, "inconsistent edge-face relationships. At least 2 solids or coplanar regions must be selected."
The process I used was:
(Units in Inches)
(a) in 3D Modelling, draw a sphere Centre x, y, z = 0,0,0.160 radius 0.160
(b) in 3D Modelling, draw a sphere Centre x, y, z =0,0,0.160 radius 0.120
(c) [check both spheres are 3D solids in the property box]
(d) In 3D Modelling, Subtract the inner sphere from the outer sphere. This leaves a hollow sphere with a 0.040 wall thickness.
(d) in 3D Modelling > Home draw a circle centre x, y, z = 0.04, 0.04, 0.5
(e) in 3D Modelling, extrude Circle to a height of z = -1
(f) in 3D Modelling, Subtract the extruded cylinder (formed in step (e) above) leaving a hollow string-bead shape.
(Step (f) has the effect of providing a hole with parallel sides due to drilling while the spheres allow retention of the flange contour. )
(g) At this point it is necessary to use other 3D shapes like boxes to subtract the shell of the sphere away to reveal the curvilinear fillet solid. I did this with several operations but what ever works best may be more of a personal choice.
(h) Usually what remains is two fillets opposite each other and they can be separated and the remote one deleted with Solid Editing > Separate tool. The result is a fairly clean curvilinear fillet in the corner.
When I created the first one, I kept a sketch with coordinates on a sheet of paper. That way I could come back and re-do it if I got some values wrong and check for mistakes.
Your thoughts about what has gone wrong here would be appreciated.
Thank you. CorelCAD Alclad Base Curvilinear Fillet 11042015.dwg
Hi AerospaceDesk,
Your model is faulty - because you've been learning as you go, you've managed to create some solids with a dimension of zero in one axis, and then combined these into a final part, which leaves some parts that will mess up calculations for later operations. As such, you're going to have some challenges with your work -
I've created a new version to show you another possibility - eg, how I would have done it - I only created one corner ( I'm lazy too ) but it works OK.
OK, some steps - I've saved the steps as I went through them.
First, I drew the main profile.
shp1.dwg
Then I extruded it to get the plate ( one profile. )
shp2.dwg
Then I changed view ( CCS axis ) and drew the next part ( Note, I use snap-to )
shp3.dwg
Then I use the common area tool ( Intersect, like I did in the first step )
shp4.dwg
Finally, I combine them all, the select "Fillet" under Solid Editing and press "R" for radius, then enter 0.04 ( your radius ) and click on the line of the corner where they two plates intersect.
shp5.dwg
And it's done - All very quickly.. Took me around 6 minutes from beginning to end, including figuring it all out, saving the steps and I got that figure from the timestamps on the files.
So in about 10 minutes you should have had the entire plate, with the flanges and the curved side pieces, ready to drop your holes in.
I'm guessing it might have taken you a little while longer - But if you can see what I did, using Intersect, Subtract and Add, you'll get those kinds of shapes done very quickly, and without any errors. Then the fillet operations will be instant and very quick :) Calculating fillets out manually is difficult ! I'm seriously impressed you figured out how to do it mathematically.
Also, if you're making lots of holes, anf you already know the co-ordinates of each one, you might want to learn some basic autolisp because then you can just feed the co-ordinates into a file, click on a pre-determined datum and have the LISP routines do all the hard, repetitive work. I wrote my screw thread routines to produce standard ISO inside and outside threads, and while it was difficult, it did make it easy to produce later - and it looks like you're doing a lot from pre-determined data rather than using the CorelCAD to figure out where to place things.
Hope this helps :) Especially as you might need to cut those flanges off and make them again, but I'd check the entire plate to ensure you don't have any bad surfaces anywhere first. You can probably do that by masking it off, use INTERSECT to keep just the center section, the rebuild the flanges using snap-to points - that should fix it up quickly for you.
David.
Thanks Cj7hawk.
I have taken all your great advice on board and have had considerable success. Thank you again. You are a wizard.
Here is my new flanged plate, but I have hit a couple of snags.
(1) When I Select-All in the Model space, I can see from the properties box some alien entities crop up. It shows "ALL(3)". One is a line, the other is an arc. It gives the locations of these. The colour of the layer for this property is red, same as my A3 drawing sheet borders and title blocks. I am using magenta for Layer 3 where the main flanged plate drawing is to reside. Do you know how to select and get rid of these alien entities (arc and line)? I do not know how to even make them visible!
(2) I am also having issues with Viewports and the size of my flanged plate. If you look in Layout 1, I created a viewport there but my flange is thumbnail size. It wasn't always like that. At one time is filled the whole viewport. The, if you go to my A3 Paper Space, I was playing with multiple viewports there (as suggested by CorelCAD's Help suite, "Working with Viewports on Sheets") and have not been able to get them to work, beyond creating them. Just for the exercise, I want to lay my views out in 1st Angle Projection. All looks a bit small really but wait, I have bigger plans to achieve.
Despite this, I had some fun with my new plate:
(1) countersunk the small holes using cone subtract (22) places - when I learn some basic LISP I may be able to make a template for an anchor nut hole with rivet hole placements and countersinking in one operation and an ability to just rotate and place anywhere.
(2) spot-faced to of the major holds to face away 1501 Alodine treatment and provide a seat for a Cupal (cu-al bimetal) washer. I had to stay within the bounds of available spot-face tooling.
(3) export as a Unix STL file.
In a nutshell, I think I am missing the bus with the selection of isolated entities, viewport and layer control.
PS do not worry about the holes too close to the side flange fillets, I need to fix that later.
Alclad Flanged Plate CorelCAD SHP100.dwgLooks like that file went AWOL. :-( Now attached.
Thanks again for your words of wisdom.
(1) The arc and the line were apparently not part of the union with the flanged plate. So I basically did as you suggested by removed the flanged plate from the space then deleting the arc and line with the Select All, Del steps.
(2) Alodine 1500 and 1200 tm products are a submersion corrosion treatment you can put on Alclad sheet to minimise corrosion in hostile environments. They have different electrical properties For example, you would have a bath of the stuff with suitable OH&S protections in place and dangle the plate into the bath and it would be there for a few minutes. Comes out a nice gold colour. Then you rinse it off in water, dry the plate and it's ready for use a few hours later. The cupal washer is used to separate the copper electrical terminals from the aluminium surface as otherwise corrosion may occur there. Just a scratch can start it. They were intended for high voltage/high current areas such as between ailerons and wing to discharge static and lightning strike currents. They high currents can flow through an aircraft structure including avionics ground points. (Gustav Kirchhoffs Laws 1845).
As you can see from my updated file, I cannot get the Viewport to display the flanged plate. I am also suspicious about it's colour in the Layout 1,
Isn't it meant to be magenta? Alclad Flanged Plate CorelCAD SHP200.dwg