A2plus What are the options for for patterns and arrays

Discussion about the development of the Assembly workbench.
dan-miel
Posts: 60
Joined: Thu Sep 13, 2018 12:29 am
Location: Spokane WA. USA

A2plus What are the options for for patterns and arrays

Postby dan-miel » Thu Feb 14, 2019 12:09 pm

When I want to add an array of parts to an A2plus file or add something like bolts and washers to a pattern of holes I have not found a good way to do this. Are there options to add arrays and patterns or what is the preferred method? I know that some of the work benches have arrays but I am not familiar with them all.
Thanks in advance,
Dan Miel.
A2plus v0.3.5
FreeCAD .17.13428
Windows 10
kbwbe
Posts: 838
Joined: Tue Apr 10, 2018 3:12 pm
Location: Germany, near Köln (Cologne)

Re: A2plus What are the options for for patterns and arrays

Postby kbwbe » Thu Feb 14, 2019 4:48 pm

dan-miel wrote:
Thu Feb 14, 2019 12:09 pm
When I want to add an array of parts to an A2plus file or add something like bolts and washers to a pattern of holes I have not found a good way to do this. Are there options to add arrays and patterns or what is the preferred method? I know that some of the work benches have arrays but I am not familiar with them all.
Thanks in advance,
Dan Miel.
A2plus v0.3.5
FreeCAD .17.13428
Windows 10
Hi Dan,
create your array with draft array in a separate new file. Then import this file into your assembly.
KBWBE

https://github.com/kbwbe/A2plus
latest release: v0.4.25, installable via FreeCAD's addon manager
Tutorials:
Paul Randall: https://youtu.be/mnkecA9S7kc
anisim (deutsch): https://www.youtube.com/watch?v=vDcaFq6IEJM
herbk
Posts: 1389
Joined: Mon Nov 03, 2014 3:45 pm
Location: Windsbach, Bavarya (Germany)

Re: A2plus What are the options for for patterns and arrays

Postby herbk » Thu Feb 14, 2019 8:17 pm

Hi,
using a array at an assembly is not the best idea...

If you want to insert screws, washers, e.g., use the Fasteners WB (to download with addon manager) klick at the edges of the holes where you want a screw and you get it insertet with the right diameter. ;)
Gruß Herbert
Jee-Bee
Posts: 1867
Joined: Tue Jun 16, 2015 10:32 am
Location: Netherlands

Re: A2plus What are the options for for patterns and arrays

Postby Jee-Bee » Thu Feb 14, 2019 9:57 pm

I don't agree
Patterns and assembly is a verry powerfull combination.

For example you neeh a extrusion profile with brackets on it. 10 brackets on a row. Every bracket is assembled with 4 bolds, 4 rings and 4 nuts to the extrusion.

patterning is possible saves huge amount of time
Even with kind of copy where all bolds, rings and nuts constraints are pre set!!

The lack of good pattern options is one of the featers that i miss most about part design
dan-miel
Posts: 60
Joined: Thu Sep 13, 2018 12:29 am
Location: Spokane WA. USA

Re: A2plus What are the options for for patterns and arrays

Postby dan-miel » Thu Feb 14, 2019 11:34 pm

kbwbe wrote:
Thu Feb 14, 2019 4:48 pm
create your array with draft array in a separate new file. Then import this file into your assembly.
kbwbe: Thanks for this direction. It takes me a while to figure out to work these things.
Jee-Bee wrote:
Thu Feb 14, 2019 9:57 pm
patterning is possible saves huge amount of time
Even with kind of copy where all bolds, rings and nuts constraints are pre set!!
I'm thinking patterning should save rebuild time because the solver is not doing calculations for each nut and bolt, instead the arrayed parts are graphical, not solids so the graphics card is handling them. Does anyone know if this is correct?
Thanks. PS. I hope graphical is a word :) .
Dan
kbwbe
Posts: 838
Joined: Tue Apr 10, 2018 3:12 pm
Location: Germany, near Köln (Cologne)

Re: A2plus What are the options for for patterns and arrays

Postby kbwbe » Thu Feb 14, 2019 11:44 pm

dan-miel wrote:
Thu Feb 14, 2019 11:34 pm
I'm thinking patterning should save rebuild time because the solver is not doing calculations for each nut and bolt, instead the arrayed parts are graphical, not solids so the graphics card is handling them. Does anyone know if this is correct?
Thanks. PS. I hope graphical is a word :) .
That's correct. The imported array is handled by the solver like one part.
KBWBE

https://github.com/kbwbe/A2plus
latest release: v0.4.25, installable via FreeCAD's addon manager
Tutorials:
Paul Randall: https://youtu.be/mnkecA9S7kc
anisim (deutsch): https://www.youtube.com/watch?v=vDcaFq6IEJM
herbk
Posts: 1389
Joined: Mon Nov 03, 2014 3:45 pm
Location: Windsbach, Bavarya (Germany)

Re: A2plus What are the options for for patterns and arrays

Postby herbk » Fri Feb 15, 2019 6:51 am

Hi Jee-Bee,
Jee-Bee wrote:
Thu Feb 14, 2019 9:57 pm
Patterns and assembly is a verry powerfull combination.
a few weeks before i was in that mind to, but there is one detail of an array what changes that:
At creating an array you have to set the parameters for the distance between the parts, e.g. the diameter of a "hole circle" at a flange to fit the screws to it.
If you have to change the hole circle of the flange, the screws placement dosn't change, because it is "constraint" by the arrays data. If you constraint the screws to the edges of a hole, they will change its placement with the change of the flange.
This behavior is in my mind a basic of an assambly, if i not have it, i don't need a assembly...

Importing an assembly is also not a good idea, because the functionality of BIM gets lost.
Gruß Herbert
Jee-Bee
Posts: 1867
Joined: Tue Jun 16, 2015 10:32 am
Location: Netherlands

Re: A2plus What are the options for for patterns and arrays

Postby Jee-Bee » Fri Feb 15, 2019 10:44 am

herbk wrote:
Fri Feb 15, 2019 6:51 am
At creating an array you have to set the parameters for the distance between the parts, e.g. the diameter of a "hole circle" at a flange to fit the screws to it.
If you have to change the hole circle of the flange, the screws placement don't change, because it is "constraint" by the arrays data. If you constraint the screws to the edges of a hole, they will change its placement with the change of the flange.
This behavior is in my mind a basic of an assembly, if i not have it, i don't need a assembly...
I don't think i understand you here.
what i think that you describe is the following: you say that if you have bracket what is assembled with a bold, ring and nut.
you have patterned the bracket with distance d_bracket and the bold, ring and nut with distances equal to distance d_bracket.
than you change something like the flange (diameter width etc). now the nut, ring and bold don't go with your change off the bracket.

i would thing that as long as the surface numbering don't change the first bold, ring and nut should follow the bracket and thus the existing pattern follows all the changed flanges.
there is only one way i could imagine how it could go wrong. i tried to do this in a screen grab from Creo. and that is that the axis of (in this case) the ring is placed of two distances from the flanges. and i can't imagine why anyone would do that...
in my opinion there is only one way the patterns may broke (visually). That is when (normally) the first pattern change the delta between each part.
Attachments
creo_assy_blob_axis_face_dist.PNG
creo_assy_blob_axis_face_dist.PNG (45.36 KiB) Viewed 350 times
herbk
Posts: 1389
Joined: Mon Nov 03, 2014 3:45 pm
Location: Windsbach, Bavarya (Germany)

Re: A2plus What are the options for for patterns and arrays

Postby herbk » Fri Feb 15, 2019 12:21 pm

Jee-Bee wrote:
Fri Feb 15, 2019 10:44 am
I don't think i understand you here.
OK, i try to make it better... but for an example with pics i have time at evening earlyest...

The array has only the information where to place the first bolt and which distances all other bolts have to the first bolt. Only the first bolt is constraint to a hole.
If you change the distance of the holes together, the array don't notice that, because there are no informations about other holes at it..
Of course it is possible to create a "assambly array function" which contends all this informations... But then you also have to give the information to which hole each bolt has to be constraint in any way... Writing this infos for each bolt to the assembly datas i think it's more work, as clicking each hole and put in the (already constraint) bolts with one click.
Gruß Herbert
Jee-Bee
Posts: 1867
Joined: Tue Jun 16, 2015 10:32 am
Location: Netherlands

Re: A2plus What are the options for for patterns and arrays

Postby Jee-Bee » Fri Feb 15, 2019 1:22 pm

The array has only the information where to place the first bolt and which distances all other bolts have to the first bolt.
that's true but it's a pity but FC don't have more, not in Part nor PartDesign.
for most(i guess 80%) cases it is enough to refer only to first object that's how PartDesign work too. that if a first feature is patterned the new one probably refer to the first on (and follow the same pattern). see example
Attachments
FC_pattern_example.FCStd
(29.52 KiB) Downloaded 8 times