Revisiting My Old Friend Fusion 360. And Searching for Documents in the Data Panel

My beacon many a night

A few months ago, I took a brief hiatus on blogging to concentrate on studying for my FAA (Federal Aviation Administration) Airframe and Powerplant tests.  As many of us encounter, there are only so many hours in the day, and the body will only tolerate so much caffeine.

I'm proud to say that those tests have been passed now, and it is quite a thrill, and yes, a relief too.

But that means that my evenings are free to pursue other endeavors, and some of those evenings will involve building a few models in Fusion 360.

I don't expect I'll get too crazy with parts, my time is still somewhat limited.  But I'll share my adventures here as I learn new things.

So what's the first thing I (re)learned?

How to search for a file I saved to the wrong location!

That's right!  I'm diligent about saving my files!  What I don't always do, is remember to make sure I save to the correct location! 

However, Fusion 360 does have a way to fix that!

First, locate the search "magnifying glass" on the Fusion 360 data panel.

Once the magnifying glass is selected, the data panel shows  a search window.  All there is to do is type the name of the document you're searching for, and click the search icon.

It helps me when I misplace my files. Perhaps it can help you too!

Good luck!  I hope this helps!

Additional Credits

photo credit: bryan... 星巴克, 慶州, 徐羅伐, 韓國, 南韓, 大韓民國, Starbucks, Gyeongju, South Korea, Republic of Korea, ROK, Daehan Minguk, 경주시, 대한민국 via photopin (license)

Improvising Dry Storage for 3D Printing Filament with Help From my Cat

A little less than a year ago, I found myself learning how to use the 3D printer at work.  It's a Fusion3 F400, and it's been a pretty good machine so far.  I've learned a lot from it!

Samples of a valve body I use for calibration.  From left to right, PLA, PETG, and Nylon

One of the things I've learned is that many 3D printing filaments are "hydroscopic". That is, they absorb water from the atmosphere.  After absorbing water, the part finish will deteriorate as the en-trained water boils as it leaves the print head.

That means finding a way to keep filament dry.

Some methods include:

• Keep filament stored in it's shipping bags until just before use.  That reduces the time that filament is exposed to the atmosphere.
• Store filament in containers with a desiccant. 
• Use a filament dryer, if you have one, such as this one from PrintDry.

Over time, I found I had several spools of partially used filament with no place to put them, and I didn't have access to a filament dryer.  

That left me with the option of trying to find a good way to store several spools of filament in a container with desiccant.  

The answer came as I was sitting on the couch, scratching the ears of my cat, "Runtley the Runtling".  

The Runtley seems interested in his potential contribution
to the 3D printing industry.

I had an empty 35 lb cat litter container!  It's free with the purchase of 35 lbs of cat litter, it's big enough to hold 4 or five spools of filament, and airtight enough to keep cat litter dry, and that's designed to absorb liquid!

This can be a dry storage container!

So after being emptied and thoroughly rinsed to make sure there was no lingering dust, the container made its way to work.  

It now resides at my desk with a few bags of desiccant and a few spools of printer filament inside.

The container at work

Add a few desiccant packets

Mix in a few spools of filamnet

Tag it so it doesn't get thrown out by the cleaning crew! 

 Hopefully this soles my filament storage issues!

Do you have a clever way of dry storing your filament?  Leave a comment! 

And thank you Runtley the Runtling for your donation! 

In true cat form, Runtley is unimpressed.  

A Fusion 360 Doodle - A Hydraulic Reservoir

With my time consumed by more than one project, I don't get the time to blog as often as I like.

But I wanted to share a 3D "doodle" I mad  in Fusion 360.

It's a rudimentary hydraulic reservoir, based on the type that has been used for many aircraft for quite some time.  I modeled it because I find a certain inspiration in a simple solution to  a problem. 

The challenge for this hydraulic system?  How is a supply of hydraulic fluid kept for the emergency system, should the primary system fail, and bleed out completely? 

The solution? There are two intakes in the reservoir.  The inlet for the primary system uses a standpipe, which sits higher in the reservoir than the inlet for the emergency system. 

Showing the different inlets in the hydraulic reservoir

The result is should the primary hydraulic system completely fail, it can only empty the reservoir to the level of the standpipe. 

That leaves enough fluid for the emergency system, allowing the pilot to do things like lower the landing gear and flaps for example. 

The primary system has failed.  But the Emergency system
can still get you home. 

 It's a clever way to solve a problem! 

Naturally, there is much more to an aircraft hydraulic system than just this reservoir.  There are pressurized reservoirs, hydraulic fuses which close if hydraulic fluid starts flowing above a certain rate, and redundant hydraulic systems found in airliners. 

If you're inclined, you can read up on aircraft hydraulic systems with the FAA handbooks found at this link.  The PDFs are free, so there's no reason not to take a look!

Dropping by the Pasadena 3D Printing Meetup

Some very cool 3D Printed Dice

It's said that we should learn from others mistakes, because we won't live long enough to make them all ourselves. 

It was in this spirit that I attended the Pasadena 3D Printing Meetup in Southern California.  Having picked up running a 3D printing machine recently, I've been trying to do what I can to learn as much as I possibly can.

And the group delivered.  There were several knowledgeable people who were happy, even excited to share their knowledge.  I got some great ideas on different materials to try. 

I was even able to share a little of my knowledge with new users.

This was followed by a presentation by Tracy and Tom Hazzard, who talked about the trials and tribulations of running a 3D printing business.  And they have experience, they run 3D Start Point.

Tom talked about building his own support structures, instead of letting the machine build them.  His goal was to reduce cleanup as much as possible.

There's some food for thought!

Probably the single best take away?  Tom and Tracy run a 3D printing podcast!  I've already looked at the first few episodes, and I'll be adding this to my regular podcast rotation!

It was well worth spending an evening with the group.  It's one I'd encourage you to attend, if you're in Southern California. 

And if you're not in Southern California, see if you can find a group in your area.  Meetup.com can be a great resource for that.

Here's a few more pictures from the group.  Enjoy!

And let's get out there and make some stuff!

A sample of PETG or PLA.  I can't remember which now.  I like the.
surface finish, and a lot of people recommend PETC

Another PLA/PETG sample.  I told myself I'd remember which was which.
I was wrong. 

A 3D printed tie.  It's printed in one piece and is wearable.
Tom Hazzard wore one for his presentation. 

A 3D printed bracelet printed by the Hazzards for their daughters wedding.
It was a wedding favor o the female guests.

A 3D printed bow tie.  This was printed as the wedding favors to the male guests.

The bow tie with support still attached.  This is the bow tie where
Tom Hazzard elected to keep the supports attached

Rope knots printed by Shorey Designs as part of a test.  The "fuzzy" rope on the
left has absorbed moisture form the atmosphere, the one on th eright was dried before printing.
That filament dryer I've heard about might be worth it. 

Getting Inspired - The SpaceX Launch on February 22nd, 2018

Yesterday, I was fortunate enough to be within sight of  the SpaceX launch from Vandenberg Air Force Base in California.  I was about 150 miles (240 km) to the south, which is easily in sight of a rocket shooting into space,

I was also lucky enough that the launch was scheduled for early morning, before the sun had fully risen.  So we were able to look up into the sky and see it.

Here's the video I captured as we stood on the balcony at work and watched it go.

The video quality isn't fantastic, but I thought it was worth sharing.

It was an inspiring sight to see!  Enjoy, and get inspired too!

A post shared by Jonathan Landeros (@jlanderos1973) on Feb 22, 2018 at 6:26am PST

A Welding Class is Over - And Now its Time to Think of New Directions

Wow, it has been a while since I've blogged.  

In that time, I've been busy in school, where I took a class in Oxy-Acetelyne welding, as well as Tungsten Inert Gas (TIG) Welding, in both steel and aluminum. 

It was a lot of fun, and a big lesson in how much skill goes into making a truly high quality weld. 

I blew quite a few holes in aluminum trying to get there! 

My best TIG/GTAW weld. 
You should see how I started!
(No you shouldn't!)

If you spend much of your time building parts in the computer, I'd encourage you to step into the shop and learns what it takes to make computer models reality.  

As designers, we should all spend some time in a place like this! 

You won't regret it!

I've been reflecting, and not the same reflecting
you see in my welding lens.

But in that time, I've come to realize that I've been neglecting InventorTales.  

My energy has been devoted to work, and school, which means my time with Fusion 360, Inventor, and Vault has suffered. 

My postings with Inventor have ground to a halt, mostly because most of the work I do with Inventor must remain behind the "Walls of Proprietary Design", and I'm not able to share my lessons as easily.  

That has caused me to rethink the direction of InventorTales....

And I've concluded it's time to step back from it a bit.  

This isn't the "Farewell" post.  I'm not shutting the blog down, I'll continue to maintain it for the foreseeable future.  I've been fortunate enough to provide information that's been helpful to the community.  I hope it continues to help in the future.  

It's been a great run for the last few years, and while I'm not going away, I'm going to admit it's time to take a "mental sabbatical"  

I intend to continue to post occasionally, and share some of the new lessons I've learned.  

Thanks for a great few years, and I'll be seeing you out in the 'Verse as I discover what new form the blog should take! 

A Quick Post for the Holidays! - Improvising a Hole Gauge

It's been busy for me getting ready for the holidays, but I did have one little tip when your practicing the future of making things.

I found myself needing to double check a hole size.  All I needed to do was to check to see if I #6, or a #8 screw would fit in a hole in a simple bracket.

Normally, I would check it with calipers.  I'm used to being able to do that.  I almost always have them available.  Almost...

Dial Calipers, similar to my set.  These are perfect for measuring small holes,
but not when you don't have them with you!
Image Credit: Wikipedia

But today, I didn't have calipers my calipers.  They were at home, and I wasn't.  So what to do? 

I realized what I did have, was a full drill index (fractional, letter, and number drills!).  In other words, a full set of improvised hole gages!

My set of hole gages!  They can also be used to drill holes! 

I just placed a few drills in the hole I was checking until I got one that told me what I needed to know.  The hole was too small for a #8 screw.  I had to get some #6 screws to do the job. 

It's not a perfect fit, but it's enough to tell me only a #6 screw will fit.
A #8 is too big. 

So as your working in your own shop, remember that while you may not have the perfect tool for the job, with a little improvisation, you may have a perfectly acceptable substitute! 

Lessons from the Real World - The Folly of Ignoring the 7Ps

There's an old saying about the "7 Ps".  To put it bluntly, the 7 Ps are: " Proper, Prior, Planning, Prevents, Piss, Poor, Performance".  I remember my Father mention mentioning it in reference to his old U.S. Navy days.

But last week, I made the mistake of ignoring the "7 Ps".  I allowed myself to fall victim to the perfect storm of laziness and complacency.  The true frustration of the situation was that I was left with nobody to blame but myself. 

Unfortunately, there's no pony to blame this time.

It was simply: My. Own. Damn. Fault.

It started with my girlfriend's car due for an oil change.  It's automotive maintenance that I've done for about 30 years.  I can do it in my sleep.  Which introduces the first demon to the equation.  Complacency.

I had the oil, I had the filter, all I had to do was get my girlfriend to leave me her car so I could change the oil.  I can do it in about 20-30 minutes, and that's taking my time to make sure I do it right.

No problem, right?  Well, remember that demon of complacency I welcomed into my world?

My girlfriend takes my truck to work so I can work on her car, easy money, as they say.  So I grab  the oil, and grab a few tools out of my toolbox, and get started.

Sure, I grab the drain pan, and the required tools, I have the oil drained in no time.  Then I realize I left the oil in the house, so I go inside to get that.  While I'm at it , I grab a few extra paper towels, I don't have enough in the garage.

The second demon of laziness has joined the party, I was too lazy to gather up everything I needed ahead of time.

The oil filter, safe on the center
console of my truck

So I move on and remove the oil filter, and realize I need to go the the oil filter too.

And that's when it dawns on me, the oil filter is in the truck.  The truck that my girlfriend took to work!

So with the oil now drained out of my girlfriend's car, I ended up taking a lovely stroll to the nearby parts store to purchase another filter.   It was on that stroll through my fine town that I was able to contemplate my mistake.

Thankfully, it wasn't long before I had completed the job.  I had to take a moment to sit down and have a laugh at my own expense. 

So what was the lesson, and the point of writing this out?  What did I learn on my Hobbit like unexpected journey to the parts store?

I realized that I had become so intent on executing my plan, I didn't actually have a plan.  It was really more of a goal of changing oil, with the execution limited to "I'm going to do some "mechanic" stuff!" in the middle.

Normally, I lay everything out before I get started, should it be a tool, a filter, or fresh oil, it's right there when I needed it.

But this time, I broke that routine.  I still had oil in the house, not all the paper towels I needed, and fatefully, the filter in a car that wasn't there.  I found myself making extra trips to get supplies that I didn't have laid out.

Had I laid everything out like I normally do, I would have realized I didn't have the filter and could have easily fixed the problem before getting started.

But I didn't, I started before I had everything laid out, and paid the price.

I think that happens to many of us in our endeavors.  We want to see action and measurable progress, so we jump to the execution stage, neglecting the planning, or "laying out your tools and supplies".

And we end up seeing action alright!  We end up acting, and then we end up reacting as we redo our efforts and end up having to adapt to challenges that a little extra planning may have foreseen.  We "take that walk to the parts store".

I'll be sure not to let this mistake be made in vain.  The next oil change, I'll have everything right where I need it, like I have in the past.  It will be a final "sanity check" to make sure I'm truly ready to execute.

And I'll be taking that lessons to other projects in my life, making sure to put the extra effort into minding those "7Ps" next time!

Please learn from my mistake, don't fall into the trap I fell into!

Don't confuse action with progress!

Lesson's From LIfe's Workbench - Working with Helical Inserts

Ahh. The helical insert.   If you've run into a mangled thread, there's a good chance you've had to use one.  Most likely it's come in the form of a tightly wound, diamond shaped wire which forms the insert.

The common helical-insert.
By The original uploader was Boellhoff at German Wikipedia - Transferred from de.wikipedia to Commons by MichaelFrey using CommonsHelper., Attribution, https://commons.wikimedia.org/w/index.php?curid=7363606

You may also know them as "Heli-Coil" inserts.  Heli-Coil is actually the name of a specific brand of helical inserts, but the names have become interchangeable, much like Teflon (PTFE), Kleelex (facial tissue), and Inconel 718 (Nickel 718).

Many of us have used them to repair stripped threads, they can also be used in softer materials, such as aluminum, to create a more durable thread.

A helical- insert used to repair a thread.

But like any fastener, they need to be placed into a threaded hole, which requires drills to tap holes, and depths for threads

Luckily, I found a great website that has the recommended taps, and hole diameters for helical inserts.

Our friends at Noble Aerospace have provided a recommended drill size chart, and a tap chart for both Imperial and Metric threads.

It's a nice resource if you're using helical inserts in your next design!

How Noble of them indeed! 

Additional photo credits:

photo credit: rustyheaps Repairing exhaust manifold, XK engine via photopin (license)

A 3D "Doodle" with Simulation in Fusion 360

A few days ago, an experienced engineer was explaining to us how changing the geometry of a component could affect the loads that it could have on how a part could handle the forces placed upon it.

Where the conversation started.
The representation of the mounting foot.

He explained that adding ribs to a mounting foot could greatly change how the mounting foot absorbed the loads, making for a more durable part. 

The modified part with ribs encompassing
the mounting hole.

So on this night I decided to build two parts pictured above,  and applied the same load of 1500 psi to them using Fusion 360.  I thought it would be a good exercise, and an opportunity to validate what I had learned.

The hole diameters and positions are the same, as well as the face bearing the load. 

After fixing the parts in the same place, I ran a simulation to see what would happen.

And the results of these quick tests was pretty interesting!

The ribbed foot had a much higher safety factor than the non-ribbed part.

The two parts next to each other.
The difference 

It was a nice exercise and validation of a concept.  And it was nice to have Fusion 360's simulation capabilities to be able to quickly test out an idea and quantify it.

Best part is now I have these parts for reference later!

It's just like a 3D note!

And finally, if you'd like to download the parts I created, you can find them here and here!

Lessons From Life's Workbench - The Blind Rivet

Over the last few weeks, I've mentioned how solid rivets are sized by part number and selected for diameter and length.

Solid rivets joining two pieces of
aluminum together. 

Solid rivets are amazing little pieces of metal.  They've been used in aircraft for decades, and if you've flown on an airplane, the odds are you've been depending on these little pieces of metal to ensure your safe flight.

And while these pieces are amazing in both their simplicity and effectiveness, like anything, they are not without their drawbacks.

They're inexpensive, but they require a certain amount of skill to properly set.  Proper riveting takes practice, and I found if I don't do it for a while, I have to shoot a few practice rivets to get "back into the groove." 

The other problem is access to both sides of the part are required.  The rivet has to be "shot" with a tool from one side of the part, and "bucked" or set, from the other.

If you're curious about seeing how solid rivets are set, the Experimental Aircraft Association has a great video explaining that here!

Moreso, it's likely that one person won't be able to reach both sides of the parts to be joined.  That means that two people are needed to set the rivet, a "bucker" and a "shooter".

Two workers setting solid rivets.

If you take a couple of moments to think about that, what you have is a rivet that maybe inexpensive, the workers required to place will be where the expenses will be found.

The blind rivet, also known as a "pop" rivet or "Cherry-Max" rivet solves both of these issues.  'For trivia's sake, the name "Cherry-Max" is derived from Cherry Aerospace, a prominent maker of  blind fasteners.

These rivets have a metal stem (mandrel) that is drawn through the rivet by a special tool.  The metal stem expands the rivet as it's pulled expanding the rivet and setting it in place.  The stem breaks off inside the rivet, adding to the rivets strength.

A blind rivet diagram.  Image from FAA Advisory Circular
AC43.13-1Bhttps://www.faa.gov/documentLibrary/media/Advisory_Circular/AC43.13-1b.pdf

The advantage of these rivets is they don't require the skill that a solid rivet requires. They also don't require that the part be accessible from both sides.   The drawback of these rivets is they are much more expensive than their solid counterparts.

A blind rivet tool, with unset blind rivets under the
"Design Differently" sticker on my laptop.

So like in so many cases in design and manufacturing, a benefit isn't seen without making a concession somewhere else.  So when all is said and done, you can still find both types of rivets in widespread use.

If you're curious about how to set blind rivets, here's a link to a great video here.

For more information on selecting blind rivets, check out the process guide  provided by Cherry Aerospace at the link here.

I  leave it to them to provide the info for you!   Mostly because I have to review it myself to refresh in my own memory!

But there you have a few of the "wheres and whys" of rivets.  I hope the info I've compiled here helps you out!

Photo Acknowledgements:

photo credit: The Library of Congress Riveting team working on the cockpit shell of a B-25 [i.e. C-47] bomber at the plant of North American Aviation, Inc., Inglewood [i.e. Douglas Aircraft Company, Long Beach], Calif.   (LOC) via photopin (license)

Lessons from Life's Workbench - Penetrant Inspection

Happy Thanksgiving to those in the United States.  Enjoy the holiday!  Here's a quick post on penetrant inspection for your consideration! 

In my aircraft maintenance classes, I've been able to try my hand at dye penetrant inspection.  

An example of cracks in a part.  This is actually from
magnetic particle inspection test.  But the tests are similar,
and it's the best picture I have! 

There are a few variations of the process, but the one I performed soaked the part in an light oil containing a phosphorescent dye.  

The dye soaks into cracks and voids in the material.  After soaking, the part is rinsed to remove penetrant on the surface of the part, and finally, it's sprayed with a powder like developer to draw some of the remaining penetrant out of the flaws so they can be seen with a UV light.  

After inspection, the part is thoroughly cleaned and returned to service, assuming it passed inspection of course.  

It's a quick, fairly easy to perform test, and can be a great to find surface flaws on a part.  

It's also messy, at least where I learned how to do it!  But a little mess never hurt anyone. 

But my experience, isn't vast by any means.  It's something I've tried enough to gain some familiarity with.  

For a little more information, check out these resources.  

Basic Principles of Liquid Penetrant Inspection

Exposing 10 Common Misunderstandings About Penetrant Testing

Lessons From Life's Workbench - Intergranular Corrosion

One of the most insidious types of corrosion I learned about in my classes is intergranular corrosion.  Aluminum alloys containing copper, such as 2024 aluminum, particularly if it's been improperly heat treated.  

The copper in the alloy comes out of the solution, and creates tiny galvanic cells that begin corroding the metal. 

The sneaky part of this type of corrosion is that it can happen deep inside the material, and may not become visible until the corrosion breaks the surface of the material in a process called exfoliation. 

 

Here are some pictures of aluminum that has some serious exfoliation.
The metal has completely disintegrated.

Another angle of the same extrusion.
You can see how the material has flaked away.

It goes without saying that intergranular corrosion is bad.  But if it can start in the interior of a material, where it can't be seen,, how can it be found?

That's where nondestructive tests (NDT) such as ultrasonic inspection or eddy current inspection can be employed to locate and eliminate this type of corrosion before it affects the strength of the structure. 

That's it for this weeks tip!  Have a great week! 

 

Using Your Resources to Design in Fusion 360

I've had a mental idea to build a simple rack to hold bolts of fabric in Fusion 360. 

It would look similar to this mobile pipe rack found on the McMaster Carr Website

But naturally, the store bought version doesn't quite meet my needs.  Murphy's Law wouldn't allow that!  So that leaves me in the position of designing and building one. 

Here's one side of the rack, mostly done,

And seeing how I don't want to work on it evening upon evening, that means I have to take advantage of every step I can to increase the efficiency my design time.

Now I should mention that many of these steps I've shared before, so this will be a link back to these posts.  But I think it's a good example of how these processes can come together and become greater than the sum of their parts. 

Here are the tips!

1) Don't Create a Model if You Don't Have to!

The rack needs to be mobile, so it needs to rest on casters.  Fortunately, Fusion 360 has a link to the McMaster Carr website that lets you insert models from their website into your design.  The part number is included, so you can always order the part from McMaster Car if you like.

Downloading these casters was more accurate and less time
consuming than trying to build my own versions

Here's the link to a previous post if you want to read more!

2) If you have to build it, reuse it! 

Every wooden piece pictured here was built and resized from
one source model.

The frame is going to be made primarily of 2x4s.  And while this isn't a complicated part, why keep drawing rectangles over and over again if you can just Copy and Paste New?  This tool allows you to copy a part, paste a new, independent version, then resize and reposition it where needed.

You can find a link to more details there. 

3) Don't rebuild what you don't have to! Redux!

I couldn't find the joist hangar on the McMaster Carr website.  It might be their, but I couldn't find it.  So instead I tried GrabCAD and found it here.

The joist hanger inserted into the model.

The download wasn't quite as slick as the one on the McMaster Carr website, but it was still a lot quicker than building the model myself. 

In Conclusion!

The design still has a long way to go.  It's not even complete, and I can already see a few changes I'll probably want to make.  But being able to reuse and download parts got me a lot further down the road in a couple of hours than I otherwise would have been.

So I hope these ideas inspire you to try a few things, and get a little further down the road yourself!

A Life Lesson - My Inspiration from a Little Black Cat

Foreword

This post is far off my usual topics.  It's a reflection on a little inspiration coming from the strangest places.

But who doesn't need that once in a while!

*******

This week has been one of those weeks.  You've probably had them, where nothing seems to go right.

In work and play, I've had projects go sideways, problems big and small plague me.  Like zombies from the grave, rookie mistakes I made months, or even years ago came back to bite me.

It was one of those weeks that leaves you asking yourself "Why am I doing this?"  (Looks at bank statement).  "Oh yeah, that's why.'

But even in this week of frustration, a ray of inspiration came to me.  And strangely enough, that inspiration came in a form I would have never expected.

A couple of nights ago I saw two of my cats, who are brothers and littermates, get into a little playful "rough and tumble". It's not uncommon, they like to roughhouse with each other.

The contenders were...

"Runtley" earned his name because he's the runt of the litter, he was born a little guy, and now, fully grown, he's small and slight of build.

This is "Runtley the Runtling"

His brother, "Scar", earned his name because he was missing a chunk of fur under his eye when we adopted him, a product of an unknown kitten misadventure. The wound has since healed, but the name remains. Scar is bigger, bolder, and stronger that his smaller brother.

This is Scar.  He's the bigger and bolder one.

The two cats wrestled on our hardwood floors, rolling about and pawing at each other as they played.

Naturally, I expected the bigger, tougher Scar to come out on top.  He had every reason to.  He has a size advantage, he had a weight advantage, he's even the more confident of the two cats.

Scar as a kitten. Bearing the mark that named him

But to my surprise, the Runt twisted and rolled, wrapped his front legs around his bigger brother, and with a heave from his back legs, rolled Scar and threw him to the floor.

The Runt's "baby picture". You can see how tiny he was.

My mind's voice shouted in it's best UFC tone: THERE'S THE TAKEDOWN! 

Scar got up and ran off, the fight knocked out of him for now, the round going to the undercat.

The victorious Runtling gave chase, as if to say "How 'bout another round!"

I instantly thought of the Mark Twain quote, "It's not the size of the dog in the fight, it's the size of the fight in the dog."

Perhaps in this case, it was a cat instead of a dog.

But in a few minutes, a runt of a black cat taught me that we all have disadvantages.  We've made mistakes, and we've all suffered setbacks.  Some of us were given a disadvantage from the very start. 

It's easy to give up and make excuses, but if you stick with it, you might just beat the odds.

Sometimes you have to be the scrappy little runt in the room, who isn't the biggest, strongest, or most confident.

Sometimes you just have to be too stubborn to quit.

Scar (left) and the Runtling.  In spite of their wrestling matches, they get along!