Find us on Google+ October 2017 ~ Inventor Tales

Sunday, October 22, 2017

Using Fusion 360's "Paste New" to create Similar Parts

Before diving into my next post, I wanted to say that I'm glad the solution I shared to fix the broken threads issue in Autodesk Inventor helped so many.  When it first occurred earlier this week, I thought it was just me.  Little did I know that so many others would run into it!

I originally found the issue on the Autodesk Community, so credit where credit is due.  The link to the post where I found the information is in the original post, as well as linked here.

Now, I'm back to a little Fusion 360 work I've been doing.

As part of an ongoing project, I've been slowly building different parts here and there, mostly off of vintage prints from AirCorps Library

One of the challenges I ran into was building a model of a continuous, or piano hinge.  It's based on the AN951 standard, which has since been superseded by the MS20257 standard,

One hinge leaf.  A little examination shows how it's mate has to
vary to mesh correctly.

Modeling the hinge isn't a difficult task, building the individual hinge leaves is easy, but they need to be made to mesh correctly.   That means the hinge knuckles have to be offset, and that's where the knuckles have to be different.

But other than that, everything is the same only the hinge knuckles vary.  So it would be ideal to be able to create a new copy of the existing hinge leaf, and make the appropriate changes. 

It turns out that Fusion 360 has a functionality known as "Paste New", and it's exactly what I needed.  It will create a new, independent copy of first hinge leaf, while leaving the original alone.  That means being able to reuse as much of the design as possible, while only changing what has to be changed.

I started with an assembly with one of the leaves modeled as its own component.  You can see that in the browser..  Now it's time to make the other side of the hinge so it can be changed so it can mesh with its mating hinge leaf.
The browser with the new part modeled
 All that needs to be done is to right click on the existing component and choose "Copy".  It's just a good old Windows Copy.

Copying the part is where it all starts. 
Now move the cursor onto the modeling canvas, right click, and choose "Paste New".  A new, independent, hinge leaf can be placed and positioned. 

Pasting the new copy using the Paste New command
I'd suggest getting the part as positioned in it's "nearly" correct position.  Then you'll be able to make changes to key features, the hinge knuckles in this case.

Positioning the part. You can use the handles, or dialog box.
Now all that's left to do is activate the new copy, modify it so it meshes with the original, and assemble.  And we're off to the races!

There it is!  All done! 

So keep this in mind when you have similar components to build, and modify it for your needs.  It can really help in not recreating extra work!

Thursday, October 12, 2017

I Can't Select Threads in Autodesk Inventor! - An Old Nemesis Rears its Head!

My threads! They don't work! 
Earlier this week, I noticed that I couldn't select threads in my installation of Autodesk Inventor 2015.  Knowing the solution, I shrugged, fixed it, and went about my day. 

I just chalked the incident up to a fluke.  You know, just "one of those things".

If you want to jump straight to the solution, here it is from my post about 3 years ago!  Fix your Inventor! 

But today, I stroll into work, and find out that several of our machines can't place threads, so I spend a chunk of my morning fixing machines, and making videos showing others how to fix their machines.

We'll, it seems there's something more to that.  The word on the street is that a Windows update to Windows 7 and Windows 10 caused the issue. It affects Inventor versions 2016 and earlier.

It makes sense to me!  Too many machines were knocked out at once! 

Thankfully, the fix is easy once you know how! 

Good luck!

Tuesday, October 10, 2017

Expanding My Comfort Zone in a Composites Workshop

This weekend I spent time away from the computer and got my hands sticky at an Experimental Aircraft Association Workshop on composite  construction.

A few of the supplies for our class.
These are the tools of the composites trade.
It was a lot of work, and it took most of my weekend.  But I learned so many things from it.  I learned from the instructor, from my fellow students, and I learned when I a step in my project went right, and I learned more when a step in the project went wrong!

The class started out with the necessary lecture on the basics of what composites were, and the basics of their construction.  That was followed by a description of our first project, a basic layup of a plate.

Several plates curing under vacuum

My finished plate, awaiting trimming.

In that project, we practiced laying up fiberglass over a foam core, carefully smoothing resin over the glass so not to disturb the direction of the weave.  The instructor took time to point out, "the weave is the strength of any composite.  If you disturb it during layup, the strength of the final product can be lost."

A video showing the hot wire method of cutting foam

My finished project
We also made a sample fairing by laying fiberglass over a form.   In involved using modeling clay to make a radius and laying fiberglass over the form.

My form for the fairing.
If you look carefully, you can see the fiberglass on the form.
Each project required finishing and trimming.  We mixed micro-balloons and cotton flock with resin to finish edges and fill voids.

My plate from my previous project.
The edges are filled with a resin mixed with micro-balloons

I even saw forms and clamps that had been 3D printed!  I would have thought the resin would have destroyed the printed plastic, but apparently it holds up just fine!
A 3D printed form for a NACA duct!
Who'd have thought.

Who would have thought that!  I go to learn a little about composites, and end up learning something I didn't know about 3D printing!

So what is the point of all this?  Sure, I could go on and tell you that this class was amazing and turned me into an expert in a matter of days.

But that would be a bold faced lie.  I'm no expert, I know just enough to get started.  My parts are barely even passable.  I wouldn't trust them in a real world application.

My three projects,.  From left to right: the Tee, made from a plate, fiberglass over a foam core
and a fairing made over a form.

But they taught me that I can learn, and I can do better the next time and to go out there and take a step beyond the line that represents the boundary of your comfort zone.  And that was the goal of the class!

And mostly, don't be afraid to try new things!  You never know what you might learn! 

Thursday, October 05, 2017

Great Resource for Designing with O-Rings

Busy times at work and home have kept me from doing much work with Fusion 360, as I've been splitting my time between a couple of long days at work, and doing a little reading on aircraft electricity for an upcoming test.

An example of an O-ring
The rendering was created in Fusion 360
But while I've been busy working and studying, I did have find myself visiting a nice little design aid I've used in the past.

In my past design work, I've had design O-ring grooves, also called, glands.

It wasn't something I did often.  As a matter of fact, it always seemed I had to design a gland right after the information I had learned had faded into the fog of time.

The process I've typically encountered for designing a shaft and bore for an O-ring involved finding the approximate size for the components to be sealed, then selecting an appropriate O-ring, then sizing the shaft, bore, and groove that would work for the design.

All this was done by referencing the design data, adjusting the dimensions, and double checking again.

It wasn't difficult, but it was tedious and time consuming.

The shortcuts to
the tools are on
the homepage

But recently when I revisited a little O-ring design, a lucky Google search led me to a website run by Apple Rubber, a seal supplier in the United States.  The panel on the right of the home page is noteworthy.   It's on that portion of the homepage you'll find the links I took the time to write about.

Apple Rubber has provided some helpful resources to design O-ring geometry, as well as choose the right material for the medium and temperature range the O-ring will operate in.

The biggest thing I used it for was their O-ring Calculator, which helps size O-Ring glands for proper size and compression of the O-Ring.  You can find that link here.

The O-Ring Calculator has provisions for standard and custom O-rings, as well as Imperial and Metric O-Ring sizes. So in short, it covers the situations the typical user will encounter.

But the page doesn't stop at an O-Ring calculator alone, and even if it did, that would be enough.

There's also a Chemical Compatibility Guide, and a Seal Design Guide.  Both of these pages are well worth saving to your browser history!

If you've worked with O-Rings before, you probably know that an O-Ring that will provide a long happy life sealing one fluid may be quickly destroyed in another medium.

The Chemical Guide allows a user to quickly choose a medium that a seal will encounter, and then tells you how materials may be expected to hold up using a "Good/Bad" type of scale.

The Chemical Design Guide using Hydrazine as an example
The Seal Design Guide is a handbook on designing for seals, and it's certainly one of the books I wish I had back when I was in  college

The cover off the Seal Design Guide.
It's available as a PDF!
So give this website a try if you're looking to design, or just want to learn about designing for O-Rings, I'll certainly be using it again myself!

And on that last note, just like my previous post on Coast Fabrication, I'm not getting compensated in any way for sharing this information.  I just like the site enough that I think it's worth sharing!