Merge sketches and other questions

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Troymx576
Posts: 17
Joined: Fri May 01, 2020 10:34 am

Merge sketches and other questions

Postby Troymx576 » Sun May 24, 2020 3:15 am

Hello,
Total noob here and sorry in advance for the basic questions, but we all have to start somehwere. I have been designing parts for years and having a friend who uses solidworks to put them into STL files for my 3dprinter and then CAD files to get CNCed. Now, due to stuck at home, I decided to jump in and give it a good effort to learn. I have watched a lot of tutorials, but I am getting stuck on some, I am sure are, very basic steps. I feel confident that I am good at sketching out what I need and want, but confused a bit on how to combine it all together. My buddy who uses Solidworks says he uses lots of sketches on different planes and then puts them together so I am trying to go off of what he said there.

Here is the basic item I am trying to make, an L shaped bracket started in two sketches. The shape is capital L bracket is at 110 degrees instead of 90. The base bottom part will extrude to 1.25" and top upper portion will extrude to 2.0". I will then add some holes in the bottom and top for bolts and fillets to smooth the transitions.

On this I thought I could sketch the bottom on the XY plane. I then did another sketch on the XY plane for the upper portion and did the 110 degrees to the base. Two sketches and a portion overlaps.

I have tried to merge the sketches, but that does not seem to work right.

I have tried to pad each sketch and then move to have it in the center with location, that was a big pain to get right. So it looked about right. I just could not fuse or merger or whatever you call it them together to make one object and then add fillets or chamfers.

I also have trouble putting the holes in the correct location on the padded plane.

I also tried to add a sketch to the pad face and it would not let me. Am I not allowed to do that?

If anyone knows a good tutorials series they can recommend that could help that would be great.

Thanks for all the help in advance.
TroyImage
Basic windows 10 and freecad 18
Attachments
freecadbasic01.jpg
pad pic
freecadbasic01.jpg (340.32 KiB) Viewed 344 times
freecadbasic02.jpg
sketch pic
freecadbasic02.jpg (360.16 KiB) Viewed 344 times
freecad basic 001.FCStd
fcstd file
(17.26 KiB) Downloaded 4 times
chrisb
Posts: 25632
Joined: Tue Mar 17, 2015 9:14 am

Re: Merge sketches and other questions

Postby chrisb » Sun May 24, 2020 7:03 am

You don't merge the sketches. You use the first sketch for the bottom pad and the second for the upright part. Merging doesn't work for padding at all, because you have so called self intersections where more than two lines meet.

Even if you solve this it doesn't help because you can pad only to one length, either the shorter or the longer.

It would be good if you use something like the snipping tool for creating the images so that they just show what is interesting, but that in a bigger scale.
Troymx576
Posts: 17
Joined: Fri May 01, 2020 10:34 am

Re: Merge sketches and other questions

Postby Troymx576 » Sun May 24, 2020 5:25 pm

I watched another part tutorial https://www.youtube.com/watch?v=geSQlBczsWY and figured out a few more items. I did the side view and did the pad on that to 2". Then I clicked the face I wanted and did a sketch on that for the area to extrude to take away to make it the right size. I am not sure if that the proper way to do it though, but it worked. The part is not pretty yet, but at least I can see something.

I did try to use the hole tool to create some threaded holes, but that did not work for me and not sure how to do that so any tips on that would be great.

An odd thing is that I went back into the original sketch and added a radius curve, but when I saved it it did not apply the extrude to that area. Not sure if I need to activate it or apply the change or something.I also tried to add a fillet to that area and it would not on that face. I am not sure why on that either.
Attachments
freecadbasic03.png
radius not showing
freecadbasic03.png (182.32 KiB) Viewed 309 times
TR-MC-Brace-V001 Troy.FCStd
fcstd file
(115.92 KiB) Downloaded 5 times
freecadbasicpart01.jpg
freecad part 2
freecadbasicpart01.jpg (353.15 KiB) Viewed 309 times
chrisb
Posts: 25632
Joined: Tue Mar 17, 2015 9:14 am

Re: Merge sketches and other questions

Postby chrisb » Sun May 24, 2020 6:44 pm

If you expect help from the helpers, why don't you help the helpers?
chrisb wrote:
Sun May 24, 2020 7:03 am
It would be good if you use something like the snipping tool for creating the images so that they just show what is interesting, but that in a bigger scale.
Troymx576
Posts: 17
Joined: Fri May 01, 2020 10:34 am

Re: Merge sketches and other questions

Postby Troymx576 » Sun May 24, 2020 7:01 pm

chrisb wrote:
Sun May 24, 2020 6:44 pm
If you expect help from the helpers, why don't you help the helpers?
chrisb wrote:
Sun May 24, 2020 7:03 am
It would be good if you use something like the snipping tool for creating the images so that they just show what is interesting, but that in a bigger scale.
OK. What would you like in more detail that you can not see in the pictures I provided and detail?
chrisb
Posts: 25632
Joined: Tue Mar 17, 2015 9:14 am

Re: Merge sketches and other questions

Postby chrisb » Sun May 24, 2020 7:38 pm

Troymx576 wrote:
Sun May 24, 2020 7:01 pm
What would you like in more detail that you can not see in the pictures I provided and detail?
I thought it was you, who wanted to show something.

In your model the problem is that you by changing the sketch you changed the internal numbering of edges and faces. This broke the fillet and the subsequently attached sketches. Have a look at this page, especially the paragraph about creating stable models.
Troymx576
Posts: 17
Joined: Fri May 01, 2020 10:34 am

Re: Merge sketches and other questions

Postby Troymx576 » Sun May 24, 2020 7:44 pm

Thanks. Will do.
TheMarkster
Posts: 1701
Joined: Thu Apr 05, 2018 1:53 am

Re: Merge sketches and other questions

Postby TheMarkster » Sun May 24, 2020 8:28 pm

I suggest to save the fillets and chamfers until the last step. These features tend to be not as robust as other features and are easily redone if need be. Try to avoid attaching sketches to faces, prefer instead to attach to one of the planes, e.g. xy plane, then adjust the attachment offset if needed. This will result in a more stable model if later you decide to go back up the tree and modify earlier sketches.
My FreeCAD video series on youtube: https://www.youtube.com/c/mwganson
chrisb
Posts: 25632
Joined: Tue Mar 17, 2015 9:14 am

Re: Merge sketches and other questions

Postby chrisb » Sun May 24, 2020 9:11 pm

I don't fully agree. If the sketches are not attached to faces, then creating fillets as early as possible increases the stability of the model with respect to earlier steps.
If the fillets are created at the end, then every change corrupts the with some certainty the fillets. If the are placed early in the modeling sequence, then all subsequent steps don't corrupt the fillets.
Troymx576
Posts: 17
Joined: Fri May 01, 2020 10:34 am

Re: Merge sketches and other questions

Postby Troymx576 » Tue May 26, 2020 4:49 pm

After reading over what was suggested I redid the part in the correct order of operations and worked within the confines of the object and it came out correctly. Thanks for the help.

Now a new question and issue.

I made a circle, pad it. I then went on the face and did a sketch that will be an extrude when done. I did not have it finished and saved it. Opened it again and go the sketch, but I can not move my new points. They are locked in place. I am thinking I have something turned on or did not turn something off. When I searched the forum is keeps showing how to lock a position once in place so I am not sure.

Thanks
Troy