Lessons from the Shop Floor - Helical Inserts do more than Repairs.

Many technicians, designers, and fabricators are familiar with helical inserts, often referred to by their trade name "Heli-Coil". 

A helical insert in an exhaust manifold

These inserts are made of a coil of diamond shaped wire. Looking like tightly wound spring, they can be installed in a special threaded hole to create standard metric and imperial threads.

In my early experience, I only saw them used to repair a damaged thread. As a matter of fact, they were used for thread repair so often, the name "Heli-Coil" became a verb. 

"Curses! This thread is completely boogered up! I'm going to have to Heli-Coil it! This why you always start a screw with your fingers!"

But as I gained more experience, I saw two additional uses for helical insert, and that's what I thought I'd share in this post. 

Wear Resistance

A 3D model of a free running (non-lockng) 
helical insert in an aluminum block

The first is to create a wear resistant hole in softer material, such as aluminum. Instead of waiting for the hole to get worn out, a helical insert is installed in the hole at the time of fabrication. The helical insert is made of a more wear resistant material such as stainless steel, although there are other materials available. This creates a more durable hole better suited if repeated installation and removal of the fastener is expected.

You might see this on a panel that needs to be removed periodically for inspection. Naturally, once the inspection is competed, the panel needs to be reinstalled. The more wear resistant helical insert lasts longer, and resists damage caused by cross threading. 

And if you have a really bad day and damage the insert, it's possible to remove the insert and install a new one without damaging the base material. 

Create a Locking Element

A 3D model of a locking helical insert.
Note the deformed thread in the middle.

Another element is to create a hole with a locking element in it. Locking helical inserts have a distorted thread in the middle that resists the screw backing out. By using a locking insert, the need for a screw with its own locking element, such as a nylon pellet, can be eliminated.

While this may seem like extra work for not much gain, this can be advantageous since you don't need to purchase fasteners with their own locking elements. Another advantage is in higher temperature applications where a nylon locking insert's performance may degrade to the point where it loses effectiveness.

And just like it's non-locking (also known as "free running") counterpart, it can be removed and replaced ,when it's locking element loses effectiveness.

 Wrapping it up

I've written this post based on helical inserts, but there are many styles of threaded inserts. Far more than I know about, let alone discuss in one post. So if the helical insert isn't your speed, there's likely another that will do the trick.  

For a sampling of just some of the different types of threaded inserts available for different applications and materials, take a look at the McMaster Carr catalog!

I hope you found this post helpful and informative. 

Let's get out there and design, fabricate, and maintain some stuff!

Appendix and Credits

• 3D models created in Autodesk Fusion 360.
• Threaded insert models downloaded from McMaster Carr
• Threaded insert models are based on the NASM/MS21208 standard for non-locking inserts, locking inserts are based on the NASM/MS21209 standard, although several standards, both imperial and metric, exist.

Finally! Looking for a video on how to install a helical insert? Check out this video here! 

Photo Credit: rustyheaps Repairing exhaust manifold, XK engine via photopin (license)

A Brief Summary of Drafting, Modeling, and Making Hydraulic Ports

Somewhere, someone is saying "It fit when I modeled it in the compuuter!"

CAD systems are wonderful tools, but, they're still tools, and largely reliant on the person pushing the mouse.

I was reminded of this when talking to a colleague about the standard hydraulic ports we use.

I know, riveting, right?

The conversation eventually turned to how the ports are called out on the drawing, and how we didn't learn this part of it in engineering school.

I recalled a time when I didn't know the standard, and how mysterious the process seemed to me as a young engineer

But when I was just a young lad, there was a crusty old salt with a black substance on his fingertips.

I'm not sure if it was grease, ink, or pencil lead. It may have been a combination of all of it.  Regardless, he helped set me straight.

So I decided I'd share what I know about the design, modeling, and drafting of hydraulic ports, in the hope that maybe it'll help someone else who faces a similar challenge..

The ports in question are "straight thread o-ring ports". In short, it's a port that allows an o-ring to be squeezed between the port wall, and the hydraulic fitting. This is shown in the image below.

The o-ring is compressed between the fitting and the wall of the port, making for a good seal.

It would stand to reason that the geometry to create the seal is pretty specific, and you'd be right.  That's where the standards come into  play. Somewhere, in the past, someone put a lot of work into figuring this out!

The one I use most at work is the AS5202 standard, it's the one shown in this image above. There's a lot of little details in there, fairly tight tolerance dimensions, angles, and surface finishes.

I won't go into all the dimensional details here, but for reference on the different port sizes and dimensions, the Parker Hannifin document can be referenced here. Rumor has it they know a thing or two about fluid fittings! The AS5202 port data can e found at the top of the document.

So, given that these dimensions are standardized, how do you make these ports?

I'm not a leading authority on the subject, but I know of two ways to make these ports.

The first, is get one of those fancy CNC machines and do some programming.

The other, is to get a tool that already has the port profile cut into it.  Then all you need is a standard mill.  You might even be able to use a drill press, but I'd defer to a real machinist on that one!

The threads are added in a secondary operation.

An example of the tools can be found at the Scientific Cutting Tools catalog page here.

AS5202 Port Tool. Image from Scientific Cutting Tools Catalog above

If you'd like to take a detour and see a machinist using a similar tool to make this port, you can check out the YouTube video here.

So now there's a discussion on the port, and how it's made.

But, how would you call these out on a drawing? While I'm sure everyone has their own method, one thing that could be taken away from this is to.... .use the standard.

Just callout the port: "by the standard"!

An example of a typical port callout

That covers some of the "big stuff", but here's a couple of trivia notes for you.

The dash means someting!

If you look at that document, you'll notice the column "tube dash number". That's a standard that seems to be one of those that the initiated assume that everyone knows. 

Notice in the image below, taken from the Parker Hannifin catalog.  You'll notice there's a column for "Equivalent Dash Nmmber", as well as a column for "Tube OD Minimum".

Now, if one takes the dash number, and divides it by the number "16", you'll end up with the Tube OD.  It's like they did it on purpose!

So if you're using -4 tubing (.250 inches), any fitting using a -04 dash number will work.

\

An example of a fittings and tubes

The standards change, but the geometry doesn't.

You might have notice that there are three standards that are listed as "Superseded" in the Parker Hannifin catalog.  And that's because the standards have changed over the decades, but the actual geometry has changed little, if any.

Some of you may even know it by the older designations!

I guess they had the geometry right even then!

The "Supersedes" comment gives you a brief history of the port.

In Closing....

I hope this little blurb was helpful. While it may be mundane and boring to some, I actually think it's interesting.  So take a look, see if it, or some form of the information helps you out.

Happy designing!

3D Printing Threads - A Few Tricks I Picked Up

When I first took on 3D printing, the subject of threaded fasteners always made me a bit nervous.  While I try to use actual hardware whenever possible, there are cases where the thread isn't used on a simple part that can be purchased from McMaster-Carr.

An example of a part requiring a thread

That meant, eventually, I was going to be faced with making a thread. What made me nervous was how to I make the thread work? Especially since I typically deal in machine threads? Machine threads can get pretty fine. 

First, I want to get the acknowledgements out of the way. I didn't come up with these ideas on my own.  I started by watching the following videos, and adapted them to fit my needs.  

The first is from KETIV Technologies, and the second, from 3D Printing Nerd.  Those videos are certainly worth taking a look. But I did need to tweak their procedure to get the result I needed.

So here's a quick rundown of the procedure I used, with a couple of changes I made to make it work for me.  

I'll be using Fusion 360 for this example.  I've found it gives me the best results, but I'm sure other CAD tools can perform similar functions.

 

Here we go! 

Thread Reliefs are Not a Relief

First of all the part I work with often have thread reliefs modeled in. I found out the hard way that these can sometimes interfere with the thread lead in.  I've had the best luck deleting them and making sure the thread starts right at the end of the desired starting point. 

The thread relief has been deleted.
Click image to enlarge

Tune up the Virtual Tap and Die Set

After deleting the reliefs, the modeled thread needs to be added.  This may be done by editing an existing thread, or creating a new one if a thread feature doesn't exist. Fusion 360 has a check box that models the thread,  Other programs have different methods of adding the thread. 

The modeled thread and dialog box.
Click to enlarge image.

Practice Your Scales

Now comes my challenge and the solution I found for that challenge. I needed to scale the thread to increase the clearance between the mating thread so it will thread smoothly. But I can't scale the entire part, because the rest of the geometry needs remain the same size.  

So I split the part into two different solids.  In this case, I used an extruded surface as my splitting surface.  The diameter of the surface is only slightly smaller than the minor diameter of the thread.  

Remember the goal is to scale the thread, not anything else! 

An example of the surface that becomes the cutting tool.
Click image to enlarge

Now the solid containing the thread can be scaled. For the parts I work with, I only scale radially.  The thickness is left alone. 

Scaling the solid that contains the thread.
Note the use of Non-Uniform Threading
Click image to enlarge

As far as the amount to scale, I've found that it varies.  I've done between 0.5 and about 5 percent.  With larger percentages working for smaller threads. However, I'm still working on the guidelines, so I wouldn't consider these numbers absolutes.  

Check the Thread Clearance

As a final check, I compare the part to it's mating thread, assuming I have it, and if I have what looks like a good clearance, I roll with it. 

Comparing the mating threads to eyeball the clearance.
Click image to enlarge

I know it's not very scientific, but so far, it's been effective. 

Glue it all Together with the Combine Command

For my final step, I combine the solids back into one.  Now the part is ready to be exported as an STL file, and imported into your slicer. 

Combining the two solids back into one.
Click image to enlarge

Speaking of slicers, I use Simplify3D at work. And what I've also found works best is to remove any supports that are automatically generated inside the thread. I've found they aren't needed, it's just that Simplify3D thinks they are.  

And thus far, these guidelines have worked well for me.  Feel free to take them and give them a try, and modify them as you see fit!

Good luck! I hope this is helpful! I hope you can take these ideas and use them as seeds to develop your own. 

And please share your tricks with others! 

Jonathan (Jon) Landeros
  

Eighteen Months of 3D Printing - Where Have I Learned to Use It?

Eighteen months ago, I took on the task of running the 3D printer at work.  It's a Fusion3 F400-S, similar to the upgraded 410 shown on Fusion3's website.

It's a FDM (Fused Deposition Modeling) printer, in other words, it melts plastic and lays it down one layer at a time until it produces the desired result.  '

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A post shared by Jonathan Landeros (@jlanderos1973) on Dec 20, 2018 at 10:29am PST

At least that's what's supposed to happen!

All I can say is that it's been fun, frustrating, rewarding, and discouraging at various stages of the journey.  I've tasted the sweet joys of victory, and I've muttered the bitter "F-Bomb" of defeat.

Most of all, I've realized that while I've learned a lot, I'm far from an expert. Because of that, I'm not going to tell you how to make a successful print.  There are plenty of people who are doing that, and frankly, they are much more knowledgeable than I.

But what I can share are my experiences watching our 3D printer making an impact in our design process.  So here I go, showing a few places where having a 3D Printer has shown itself to be a helpful part of our design processes.

One disclaimer before I get started.  I can't share the real parts online.  Words like "proprietary" and "security" start getting thrown around.  So I have to use "surrogate" parts that represent the concept.

Thanks in advance for bearing with me!

1) The "Show and Tell" 

There's nothing like holding a represenation
of the part in your hand.

When I think of 3D printing, this is the first application that comes to my mind.  It's simply a cosmetic print meant to give an idea of the "form and function" of the part.  In our case, it didn't do anything but give everyone a sense of size and shape. 

This might seem simple at first.  With 3D CAD Modeling tools, we can model our designs precisely.  So why "waste time" printing a part that's just "for looking".

Well, I know I've fallen victim to being able to zoom into a small screw until it looks like a table leg.  And with that, comes a distortion of scale that can affect those of us that live in the real world.

And I know I'm not the only one.  I've heard more than one person say, "I really didn't think about big/small that part is!"

A particular example comes to mind.  I was in a meeting where the projected image of the CAD model rotating on the wall was completely ignored because engineers and customers were drawn to the 3D printed model that represented a much more tactile experience that couldn't be experienced with the 3D model.

2) The "Assembly Test" 

This print is in reality a series of parts that make up an assembly.  It may even be a combination of real and printed parts.

A sample part with a real hydraulic fitting threaded into one hole

The purpose of this part is to ensure that the parts you've carefully designed can not only be put together, but put together easily.

I can see which fitting will have to get torqued in first! 

For example, can a bolt be inserted into the bolt hole, and once in there, can the wrench follow up and turn the bolt once it's in the hole.

3) Tooling and Covers

I've lumped these tooling and protective covers into the same category, partially because the two sometimes blend into each other, at least where I work.

An example of a protective cover that has a unique shape

Because the 3D CAD model exists, it can be relatively quick to create a negative of the part, then print that negative as quickly as a few hours.

An example of a cradle created by creating
a negative of the part. 

Sometimes these shapes are odd or unique, and can't be easily duplicated by the machine shop, or frankly, the machine shop just doesn't have the time to make them.

In any case, 3D printing provided us with the ability to create odd geometry quickly, without disrupting other operations.

In Conclusion

My intention here was just to share a few cases where I've found 3D printing helpful.  By no means is it comprehensive.  If anything, I hope it provides a few ideas, and dare I say, inspiration.

I think it's also important that we bear in mind that 3D printing is a new tool that can supplement existing tools.  Don't by a 3D printer thinking that you'll be able to shut down your machine shop, woodshop, or welding shop. .

So take these ideas and make them you're own.  And feel free to share in a comment if you have a good use for 3D printing in your home or office.

Acknowledgements

• Valve body modeled in Autodesk Fusion 360 using plans from my Aircorps Library subscription
• Hardware downloaded from McMaster Carr

Painting PLA 3D Printed Plastic.

The valve body part I use for everything from machine
calibration to well, paint tests! 

One of my newer endeavors is running the 3D printer at work.  And with any new journey, it's got is rewarding victories, and frustrating setbacks. 

My most recent "let me figure that out" moment came when printing a "presentation" part, meant to give an idea of shape and volume.

I printed the company logo into the part, because that's just good marketing right there.  But then came the suggestion....

"Can we paint the logo to make it pop?  Do we have an white out anywhere?" 

After a build lasting 22 hours, I wasn't willing to roll the dice with white out.  But while home sick, recovering from the flu, I had an idea (fever dream?) to go to the local crafts store and see what they had for paint. 

So once recovered, I wandered off to the crafts store and found a paint pen.  Not willing to try my first attempt on the part at work, I tried it on another PLA part I had. 

The results for a first attempt weren't too bad.  We're they perfect?  No. but it'll do for what we're currently after, and if I do say so myself, not bad for a first attempt.

The "paint pen" and its willing test piece

Have you got any suggestions for painting PLA?  I've heard acrylic and spray paint work well, but haven't tried it myself.  For that matter, has anyone tried the good old fashioned whiteout?  Maybe I'm being a little elitist and it really is a good choice!

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!