Hi Everyone,

Pretty impressed with my 1 day trial with MOI 3D so far - amazing software!

As I am interested in 'automated' design with least amount
of steps possible, wondering if it is possible to do the following
with a script or ; if someone can demonstrate the fastest manual way in moi3d...

Basics:
We want to create a passthrough hole in a solid surface with an offset
using the component that is passing through as the 'geometry'
reference. So, we create a pass through hole (with offset)
and position the fixing through/into the material; all in one go.

Example Components:
A: 1 x aluminum 'flat bar' created in Moi3D as a solid
example dimensions L:100mm W: 25.4mm Thickness: 12.7mm...
B. 1 x standard machine screw say: m6 x 30mm. Head dia. ~12mm

B1. 'Advanced' detail: screw head could also fit into a
counterbore or countersunk hole detail where head height approx ~3.7mm. If countersunk then the included angle might be 90degree.

Requirement/operation.
1. Screw fixing is placed through the flat bar/solid.
2. A 7mm thru hole is created for the screw; offset = 1mm allround or 0.5mm each side of the screw diameter.

3. Basically, an offset hole for the thread size is created and then ideally the screw head is one of 3 situations:

3.1 placed on surface of the flat bar [Example #1]
or
'ADVANCED' :
3.2 counter bored [#2]
or
3.3 counter sunk [#3]

Other notes:
4. The screw is not deleted when creating the 'hole geometry'
it is placed into the face of the material or into a basic countersunk or counterbore detail.

Look forward to hearing from anyone who can 'enlighten' or help with this!

Thanks

Stefano...

Hi Stefano,

While I think a script could be written to do what it sounds like you're asking for, it is pretty quick to do it by hand using MoI's normal tools. Briefly, create the unthreaded fastener using clearance diameters and then use the Construct Boolean Difference tool to cut the appropriate hole, using the fastener as the cutting object. As you're new to MoI, I would encourage you to spend a little more time getting the hang of the tools already provided as you'll then develop an appreciation for just how quick and precise the UI already is. I think one of the tricks for learning MoI is unlearning some of the assumptions about workflow from other tools.

If you are also interested in threaded parts, you might check out Max's NutsAndBolts script http://moi.maxsm.net/files/scripts/NutsAndBolts.v.0.96.2015.06.22.zip which does a great job of creating standard hex-headed fasteners, but it may do more than you're asking for at this time.

--Larry

Hi Larry, thanks for your fast response.
It's the idea of creating fasteners with clearance diameters
I dont like much; reason is I see it as duplication...

If you goto any fasteners website
really good 3d models exist so we 'ideally'
want to use the original object for 'fastener hole'
or its seating details.

The post was also trying to indicate screws are pretty standard so even without a 3d model it would be interesting to understand how to pick a point and create the hole detail 1st, ideally in a click.

Kindest Regards

Stefano

Hi Stefano,

Maybe someone else will have a better way to answer your question, but to me, it sounds like you're asking about the simplest way to cut holes to accommodate fasteners while allowing for standard clearances. If you already have a model of the fastener, then you could use it to cut the hole with a boolean diff but that hole would not have clearances which is why I offered the suggestion to create your own cutting object with the desired clearance.

> The post was also trying to indicate screws are pretty standard so even without a 3d model it
> would be interesting to understand how to pick a point and create the hole detail 1st, ideally in a click.

Given your solid bar, use the Cylinder command to create the appropriate sized cylinder, then use Construct Boolean Diff to subtract it from the bar. Or you could use Circle to create the curve, then Extrude it followed by the Boolean Diff.

--Larry

Hi Larry,

If we take an existing shape or fixing then it might be:

A. 'Complex' or highly detailed wall-plug like I am now showing from 'fischer'
or
B. A very 'simple machine screw' like a M6x30.

All these parts have something in common; they have simple outlines
and we have the origination 'somewhere' on the drawing.

THE IDEA/CONCEPT or 'WISH' IS...
I was hoping that 'object' (or maybe its contour-outlines) could be used to create the
clearances or offset-sized hole details. I think it should be this original component that creates
the 'fixing seat' or what you might call the 'clearance fixture' whose shape is 'welded'
into the material.

!! I do not think a user should have to redraw anything in this instance !!

If you see the attachment, and go left to right. This is what I was hoping would be possible
in a 'workflow':

1. LEFT:
Manual operation: User takes 'Plug' (or a machine screw) and this is positioned in the material.
Bolean operation with 'clearance' is appled
OR
Script idea is: USER KEYS in basic shape for the Fixing and/or optional
applies clearance data to xyz 'centre hole position/s' - before making #2 happen.

2. CENTRE: The hole and/or fixing-seat is then made into solid material.
The hole in this instance to hold the plug is in this instance "drilled and countersunk".
IDEALLY this geometry is made from the border-geometry of that fixing.

3. RIGHT: The hole has been made and the screw is pushed in.

I hope this is clear (as mud)?

-- Stefano

link to that file is here:
https://www.dropbox.com/s/a98o0dmcnmda34v/Test-fixing.3dm?dl=0

Hi stefano, well the example in your link above is quite tremendously complex, this piece for example is made up of 1412 faces:



I don't think it's very likely that something of that level of extreme detail is going to be able to be automated robustly.

i guess conceptually you would want to be able to generate an offset of it. But offsetting such a complex object is very difficult. For adjacent surfaces, the offsets of those surface only touch each other if the base surfaces are tangent to each other. Any surfaces that meet at a sharp edge instead of meeting smoothly need to have the offset surfaces extended and intersected with each other. The mechanism to do this in the geometry library that MoI currently uses is not very good at that particular type of thing and so it's very unlikely that you would be able to use MoI very well for this type of of processing.

- Michael

And a Scale 3D ? 2D ? for simulate an Offset...

Hi Stefano,

Okay, so to avoid drawing the cutting object you have imported it from another source. What about considering the Transform Scale command to create the necessary clearance (offset)? Scale 2D would seem to work for round or square cutting objects (symmetrical about the primary axis). The command asks for a scale factor rather than a clearance dimension or offset, so a little math is required to provide that. I don't think a 2D scale would create a proper thread form, though a 3D scale might.

Once the cutting object is scaled to include the desired clearance (offset), then it would be straightforward to locate (Move, Copy, Array) the cutting object on the part and use Boolean Diff to cut the necessary hole.

Depending upon the desired outcome of the model (construction drawing or rendering), you could then either dimension or put the original (un-scaled) cutting object in the hole(s).

While a script could be written to handle scaling the simple cases, if you need more complex forms or controls, I suspect you're asking MoI to go beyond its intended function.

--Larry

Hi Michael,

I totally agree the shape is complex in its composition but
overall the shapes (outline) is simple. I originally posted this to the forum because I do come from
a 2d background and can of course visually work around this problem without
making any holes; which is what i did on my 1st model. It was absolutely
amazing i could pass a screw through a solid piece of metal without drilling it ;o).

Jokes aside; I am likely using 3d for the 1st time to see what i might be manufacturing
before I make it. I usually do have to build it or get small details signed off by clients
or my structural engineer. I really don't want to be drawing too many objects that just get
'trashed' or welded into other solids. I guess over time we can all have libraries of
parts but I am not that sort of cad-geek. More into 'ideas' and 'workflow'
probably what attracted me to MOI3d many many years ago.

My conclusion is...
Simple machine screws or making the hole outline must be easy as creating
a 2 cylinder object as Larry was indicating but that is not why I posted
the simplest of examples in the 1st place. Perhaps a tool to 'loft' 2d to 3d
takes care of complex shapes which is where I think Pilou was coming from.

Eitherway, I was hoping there might be a function that could detect edges
of simple 'component outlines' and use this as an offset path.
We are always talking about simple shapes here and thru holes with perhaps
one angle to worry about on countersunk screws. Thats all.

I am quite interested in how to do scripts or use them but don't have
the skill (or time really) to dive that deep at moment. I am still thinking
a macro/script idea to point and click these hole features would be a very
nice idea and likely pretty original...In this instance...

Here is my example of the 'hole macro'

----------------
> Create shape/object/part/label name: "FISCHER 8x100 - 1"
> Pick hole centre point(s) in solid surface face(s).

SOLID PART 'CUT' DATA (material removal):
1. create hole lengths: 100mm
2. through hole diameter: 8.5mm
---
THEN: counterbore or csunk detail:
3. Place head diameter hole: 12mm (on front surface).
4. AND rebate #3 down to head height: 4mm
allowing for 5: inclusive Head angle: 80-100degree (or simple COUNTERBORE).

6. Create 2 copies of shape, trash one (on the weld) put other in hidden MOI3D
layer (use the object name above).

DONE.
------
Please note subconsciously, I might have got this 'macro' or workflow idea from
how they annotate drawings to ISO/ANSI standards.
There is seemingly only 3 main types of holes for screws.
Passthru, countersunk, countebore. All very basic.

https://mae.ufl.edu/designlab/Online%20Resources_files/fastener_handout.pdf
> See PAGE 9 please <

---------------

Thanks for your input and considerations!

--- Stefano

thanks Larry, i've noted that but i need to relate to the functions another day...
is there any videos on how to do these particular functions you mention the best manual way?
I also listed how basic (and powerful) I think a 'hole' macro 'could' or should be. Tx Stefano

Hi stefano, well there is a method for generating an outline, it's the Construct > Curve > Silhouette command. But it generates an outline based on a viewing direction. If your shape was symmetrical then maybe something like generating a silhouette of the side and revolving it could work. But just your first example shape there is not symmerical, it's got these pieces sticking out the sides:



- Michael

Hi Michael,

Correct me please if I am wrong...doing this by script is clever but manually (for now) it might be best done like this...

1. Countersink head part; we just use concentric / 'lofted' circles representing the back of the countersunk part to create:

male solid 1 ( with clearance )
for the 'plug head seat'(!!!)
E.g. top-down: 1st circle 12mm dia 2nd dia circle 8.5mm, spaced apart ~4.5mm becomes the male "cone" shape...

Solid 2
The main shaft as I indicated in my preferred macro approach can just be 8.5mm diameter 'rod/cylinder' or what later becomes a pass thru hole at 8.5mm x 100mm length.

We then join 1 and 2 together so the cone and the rod become a united clearance shape...Then bolean into the "block"...and the male solid does its job...

!!!
In this particular example please note this plastic plug simply passes
through and is seated in a piece of solid aluminium (say 20mm depth). It sits inside the aluminium fairly snugly, then what protrudes (about 80mm) goes into a wall.

The screw head will sit flush with the front surface face of the aluminium.

I hope its that simple.

If I could have a video of these functions in context it would really help get me making this object to an almost perfect and realistic drawing....

I will post the results here ;0)

Stefano

These pieces are not yet existing here ?
some have their 3D Cad yet made that you can free download...
https://www.mcmaster.com

In relation to this topic does anyone know of a way to export from OpenSCAD and import into MOI?

The nature of OpenSCAD makes it simply to create "tools" to generate objects that are similar in shape but vary in dimensions.


Anyway back to MOI.

Creating a library of shapes may not appeal to some but it is easy to do. Revolving a profile can create many of the required shapes.

I may spend hours and hours working on a project so spending a few minutes to add a new shape to my library doesn't seem a such a chore.

A given fastener may have single CAD model but there may be a good deal of variation in the "hole" needed for the fastener so I cannot (yet) envision an easy way to use the CAD model as a template for the "hole".


Interesting discussion. Looking forward to see where it goes.

Thanks.

Frederick

Hi Pilou, yes McMaster is a great resource nonetheless they will not have that plug shape,
which was the best 'reference' example I could have provided as that is for a real job
(and on my 1st MOI3D model).

BR Stefano.

PS. 2D DXF Attached for anyone looking to show me (ideally by a video) how they would do it from 2D...

Hi Fred,

this might be one route worth exploring...

https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/STL_Import_and_Export

by posting to or reading this page:

http://moi3d.com/forum/messages.php?webtag=MOI&msg=7046.2


"
7046.2 In reply to 7046.1
As exist some OBJ importers for Moi, that should be not difficult to import it ! ;)
http://moi3d.com/forum/get_attachment.php?webtag=MOI&hash=1672dd45da321f51513d74216e78cd7b&filename=importObj.zip
by Max Smirnov

The free MeshLab can convert STL in OBJ
http://meshlab.sourceforge.net/

then you can use the subdivider by Max Smirnov again ;)
http://moi3d.com/forum/index.php?webtag=MOI&msg=6674.82
"

Hi stefano, yes if I understand you correctly using circles at different stations and doing Loft could create the type of shape you want.

The other way you can make cylindrical type shapes is by having a 2D profile and using Construct > Revolve.

That looks like this - if you have a 2D profile like this:



You would select it and run Construct > Revolve and when it asks you to pick the revolve axis start and end points you would pick 2 points running down the center line like this:




That then would make a result like this:




- Michael

Hi Frederick,

re:
> In relation to this topic does anyone know of a way to export from OpenSCAD and import into MOI?


That will probably be difficult because OpenSCAD outputs faceted triangle mesh geometry, it doesn't make NURBS surfaces like MoI uses for modeling.

- Michael

About automation...
You have also the Nodal Elephant by Max Smirnov
Elephant Repository: French / English https://moiscript.weebly.com/biblio-elephant.html

With only one model you can elaborate some others with any variations embeded!

Hi,
perhaps creating an object library may help.
I made a Cap Screw Library for M3 to M12 with hole cutters as shown in Gif.
Create a drawing of whatever fittings you use and import.
Hope this helps.
Barry