Monday Night Meatloaf 103

In this episode of meatloaf we take a look and do some testing of fastener preload, 3D printed file handles, grinding book, Bakelite polishing, grinder wheel storage tote, priority mail box liners, micro mesh graded abrasives.

[@felixcosty]

Thanks for the video. For your wood box in a cardboard box, use glue, and cheap white glue you would use in school. Place wood in bottom of box apply glue around the edges of the sides except the top edge place sides in box, let dry. when you ship put everything inside and nail, screw, glue top down, ship next day. Very cheap and glue and wood joints are one of the strongest. If you glue the top down the person getting the stuff out of the box will have extra fun, but the stuff will get there in one piece.

[@mikemarriam]

Tom, I greatly appreciate your videos. It really doesn't matter which project you're working on either. I always try to distill the fundamentals from whatever I watch. On a completely separate subject I recently coined a new term: Liptonite. Thats what you apply to a workpiece when you break out a file to take just a little off instead of setting up a machine. You heard it here first.

[@aserta]

-There is a way to make the Allen wrench without any kind of welding. -You take the Allen keys of your choosing, find matching socket wrench for them, slip the Allen keys inside the hex socket and split the end (hacksaw) so it can't get out through the hex side. -Then just get a piece of square stock that fits the square drive snugly, a piece of round stock that's slightly thicker (than the square stock), not much, and then drill a round hole through it. -Put the square stock in the hole, peen the round rod over it (or add a pin) then attach the two hex drivers on the square ends. That's how i did my Allen wrench for my car many, many years ago when all i had access to was a drill press. Works just as well, and, it doesn't require you know how to weld, neat first project too. Worked really well for 7 years until i lost it and made a new one by buying two Allen T wrenches (all metal, one piece off eBay), grinding the handles half way, then welded them together in to something very much like what Tom has and polished the welds. Looks pro, looks factory. I was bored. :)

[@midgoog2]

In a former life one of my periodic tasks was to check conrod bolt elongation. I spot drilled each end of the bolt to be checked, measured the length, then fitted the bolts to a conrod applied the specified torque then measured the "working" length to see if they performed to spec before releasing them to production. In the engines we produced the bolts were tightened using the angle torque from nominal snug torque method which put the bolts into the plastic region, so each time they were tightened they got longer. This is why bolts tightened to yield point as is common nowadays should be replaced whenever rebuilding an engine. Cheers Eric

[@briantaylor9266]

For your box liner, I would use rabbet joints. Cutting the joints is well suited to production, far faster and easier than box joints. The end pieces would have a rabbet on each edge. The side pieces have rabbets top and bottom only. The top and bottom have no rabbets. The end user binds the box together with fiber reinforced tape, supplied with the kit. Those that want belt and braces can put a bead of wood glue in the rabbets before taping.

[@robertvanhoose2437]

I'm thinking a simple box joint-style tab and slot for the corners (with only 1 or 2 tabs) would prevent the side pieces from sliding past one another. Then a pre-formed sheet metal or plastic corner that would slide over the assembled pieces to keep them in square, plus provide reinforcement against blows to the corner. Then some double-sided tape pre-applied to the perimeter of the top and bottom to seal the deal. IANAPE (I am not a packaging engineer).

[@briantaylor9266]

I like the tab and slot idea from the strength perspective, compared to rabbet joints. CNC would work, but that's slow. Maybe template routing? Tom will have to weigh strength vs production time, since the production time is where the real $$ are.

[@briantaylor9266]

Maybe Tom can select his preferred options and some of his woodworking viewers can test them.

[@frednewman2162]

Great demonstration but have to say, I was actually more impressed by the Tig tacks on the lock washer holding at that stress load, or even the lock washer itself not distorting! Nice demonstration Tom!

[@bcdesignco8013]

Great video! Awesome to see such a small SHCS withstand so much force! Also keep posting machine shop organization tips, like your grinding wheel stand! Ideas like that translate into more efficient work spaces, and I'm sure we could all use some help in that area. Can't get enough of your machine shop content! Thank you so much!

[@bcbloc02]

Actually if you want to be picky about fastener loading we need to know what the bolt stretch is for the torque applied. The box in a box is a good idea but it needs interlocking or fastening to not just blow the whole side out. I was chastised by some for using bolted connections on my bridge crane I built and had a hard time explaining how the bolted connection was stronger than what a perimeter welded connection would have been. That was assuming he bolts were loose and in pure shear, once the bolts are tightened and the friction of the joint is added then it gets super strong. The real world testing is awesome. I love it.

[@peteferguson7024]

Is it me or has Tom become the filing guru :)

[@bcbloc02]

Pete Ferguson Yes I am looking forward to this years filed from billet vise. :-) How many albums is that?

[@OldIronShops]

+Pete Ferguson always was he's just letting us in on it.

[@jaynegus4526]

A friend of mine received in a flat rate box an expensive replacement part to an antique gun he was fixing for himself. He showed me the excellent job the shipper did to protect the item during transit. The item was wrapped to isolate it and then they took the time and expense of using expanding spray foam insulation to encapsulate it within the package. The shipper even had the item centered in the box so it was protected evenly on all sides.

[@63256325N]

First thought when seeing the grinder wheel holder was....toast, warm, fresh toast. Great experiment. Surprised me. Thanks Tom.

[@swellwelder]

I personally love this kind of demonstration. Back in high school physics it was the highlight of the day when we had hands on lab demonstrations. Much more interesting than all the book learning stuff, although through life, the book learning stuff has been more useful!

[@danbentler9742]

Tom Looked up clamp force vs torque of fasteners. I remembered from previous lookups on subject it is fraught with uncertainty. Yes there is a formula where if you know torque and bolt dia you can calc clamp -- IF -- you have a good value for K factor. Remember torquing method for the turbine at Trojan Nuclear Plant. Studs had heaters in them. At temperature the nuts were tightened and then heaters turned off. A related tangent? Last week in my Weird Science kids and I took a piece of line (1" nylon braided). Let them try to pull my truck over a curb - did better than I thought. Then had them do tug of war to attempt breaking it. Tomorrow we tour a wire rope and rigging outfit and they will take their rope and break it for them Dan Bentler

[@DonDegidio]

Tom, Nice experiment. Would be interesting to see if the bolt stretched. Maybe do another test off camera, measure the length of bolt before and after.

[@ajtrvll]

Small hobbyist do-it-yourself-er that enjoys these mild-mannered talented craftsmen showing off their craft. Always watched and learned something without thinking of the effort that creators put into making these videos. The subscribe/like reminders are important in a world where good things are far too often taken for granted. Really enjoy Tom' Lipton's videos... in my top 5 favorite machinists video. Keep up the good work, sir !

[@thedge7]

Been building a box-inside-of-a-box for shipping for decades. I couldn't imagine paying for the parts... However I also generate a lot scrap plywood.

[@dejanira2]

The priority mail box ideal is great. I live near a convention crating company and have built many projects using the free wood they put out for the public. As for holding the shape, I think shaving off 2 layers of 3 ply would hold it together just fine. I have come to look forward to your interesting projects that have always been enjoyable!

[@Skraap]

Oh boy Tom. You promised the Internet breakage and you didn't give us breakage.

[@capin232]

Your best one yet Tom, I can watch this criteria all day long and know I'm learning while watching. Thanks, Brian

[@Hangar18Fabrication]

Great episode Tom. I really enjoyed the fastener testing. I used to make cold header tooling for the fastener industry, and I am still fascinated by fastener technology. And, you are absolutely right. . .it can be a very complex equation! Throw some shear loads in there with the clamp load, along with some vibration, and it starts to get really crazy. It's akin to tightening a very, very stiff spring.

[@mtericktucson]

Tom, I'm a diesel mechanic. I wonder if the speed nuts we use would be a way to mass produce these, You are on to something here for sure. These speed nuts typically crimp onto sheet metal for example, a mirror on a big rig. I thank you for the post, your channel takes life to the next level. I'm a fan for sure! I hope to make it to the Z bash next year. I live south of Tucson, so it is an easy day drive for me. You guys are great!

[@randallparker8477]

In kind of the same question, "someone" used "standard" grade 8 bolts and nuts on the turbine casing of a steam driven fire pump on board a navy ship. When the turbine got up to temp and speed, the bolts started getting loose and some high pressure (450lbs) steam leaks were witnessed. After shutdown, hammer wrenches were used to tighten them. When testing at temp and pressure after that, the bolts started popping and shooting into the overhead and ricocheting around the space, not to mention massive steam leaks and a rapid rise in temperature in the space. #1 - wrong bolts and nuts for the application not to specs, #2 - retightening while the fasteners were still hot "bad practice". #3 - the supervisor told the "someone" to do as he said. It was quite an exciting experience for several "someones" that day for sure.

[@LarryDoolittle]

Nice test and your right so much strength!

[@danielwerger5641]

Very cool Tom...! It's amazing the strength of day to day fasteners we use all the time.... More of this please.....!

[@aserta]

For the wooden box, you need the plastic panel holders that are used to hold partitions in offices. They have straight holders (to tie two panels end to end) but they also have 90 and 45, now, the 90 is the kicker and it comes in various thicknesses. I used this to make a 40 by 40 by 40 box (HDF walls) that was used to cast a block of concrete. After the concrete had set, the box was used to move the cube around (so you can imagine how strong the deceivingly weak looking plastic was). I don't know under what name you'd find them in US but by telling you that you'll find them in the trim department, that should be enough.

[@silveradoman298]

Really enjoyed the test Tom. Thanks

[@gwood64]

Very interesting and enlightening video as always. Keep em coming.

[@jeffryblackmon4846]

You are always doing something interesting. This is no exception. Thanks for the all your presentations. There is a lot to learn from you!

[@bensthingsthoughts]

Good !! Very good !! I loved the test procedure...

[@mxpimp47]

Good content as always Tom. I had a gentleman roughly 73 or so years old who packed up a radius attachment for my Hardinge HLV-H lathe in a pine box similar to what you did. Worked well, it was 1/4" ply screwed together though. I have since thought of the same thing when I ship heavy items in the flat rate boxes.

[@Lonczakt]

Very interesting! Thanks, Tom!

[@gtmcfar]

Very informative video, Tom. Thanks.

[@ExtantFrodo2]

Always love test and measurement. Great video. Like it very much.

[@FredMiller]

Great test with surprising results. Very entertaining AND educational. Thanks for taking the time to put it together and show! Fred

[@ericallen1045]

I love when you test things like that. So often I find myself wondering is that enough strength

[@jimnutzman8637]

I enjoyed this video a lot!

[@QtmMtrlzr]

Awesome episode! Love that you took the time to setup the test apparatus. Keep up the good work Tom.

[@eformance]

Glue and staples is a good choice for the box. An alternative is to do tab-n-slot corners with a hole down the center that you can push some bailing wire or a long nail down. Rabbets in the top and bottom would help to prevent lozenging of the box, add glue and you probably have more than double the strength.

[@JoggingWithForks]

Love your videos! I have learned so much from watching you over the years, stuff I use on a regular basis building model engines.

[@mikenixon9164]

Tom I liked this test tested a lot higher than I thought. keep the videos coming!

[@ziggfreud9820]

That test was awesome!! Love how you set it up, taking into account what happens if it fails, all the supporting gear has to be above the clamping force including newly tig welded eye hole. Very cool!!

[@JonRUpton]

Tom, for your box idea, try dry wall screws. They are cheap, easy to install (just pre-drill) and they should be strong enough. You could also glue the edges and bottom for more strength. The wood will fail before the glue does. Thanks for making the entertaining videos!

[@yosmith1]

Always a learning lesson watching you video's, Tom Thanks for sharing!

[@jcs6347]

Great video Tom! I loved the testing and discussing your thoughts on how you were going to accomplish it, thanks.

[@PMPCMining]

Awesome video Tom. It has always amazed me of how strong something small can be when used properly. As far as your box liner go's. Keep it simple, if you are going to have them cut out. use one mortise and Tenon for each side just to lock the pices together. Packing tape or fiber tape would do the rest.

[@lwilton]

Wheel holder: attach some sort of bail rod that you can snap through the wheel centers and keep the wheels in place if the holder is tilted. Then put a suitcase or drawer handle on the back side, and you can grab the thing with one hand and carry it over to the grinder without worrying about dropping wheels.

[@JohnBare747]

Good test Tom, a good bolt holds it's own.

[@davidwright4541]

I am more than impressed with the weld ability of the eye bolt you fashioned. Great test! dkw

[@darinspicer1301]

great stuff Tom! Keep the video's coming.

[@scottsession7789]

Thanks, I enjoyed the video. Scott

[@ls2005019227]

Great video content Tom! I actually watched the crate/bolt stress tests first, and came back to the ML103 to get some of the discussion behind the tests. Thanks again!

[@thedrubaru]

You could cut vertical dados into the long sides of the wood pieces that the shorter sides can slide into. They would keep the shorter sides from falling into the box and would also allow for shipper to create a more custom fit to the piece that they are shipping if they wanted to. You could also include a little tube of glue, similar to what Ikea packages with some of their hardware kits, to make it even stronger still.

[@OldIronShops]

meet test but you know we were all waiting for the destructive test

[@superiorshooter]

Very fulfilling episode of Meatloaf. Tom, I got the meat sweats from all that knowledge.

[@brosselot1]

Great video Thanks for sharing. I have a background in Structural/Mechanical Engineering and I'm always amazed just how many bolts or lack of bolts to make up a steel connection. Thanks Tom. James Greene will love your box inserts BOX in a BOX.

[@ScoutCrafter]

Awesome Tom- Hey if your looking to make some quick $$$ forget the box liners and weld up some of those nifty Oxtool lifting rings and sell them in sets of four... Cha-Ching!!! 😃👍

[@jerrywells4380]

Very enlightening! Always enjoy your ingenuity. That little test really shows the capability for the Mini Pallet holding power as well. My vote for the box fastener, goes for the tie wraps, not only for the strength but resiliency.

[@phooesnax]

Interesting stuff Tom thanks Jim

[@michaelyopp4236]

I like this type of video. I learn from them

[@GnosisMan50]

I really like that grinding wheel rack. I need one myself though I might make it out of wood instead. Thanks for sharing Tom.

[@tek4]

I live that you used nylon webbing, we call it mule tape, and use it for some conduit pulls. electrician here. keep up the great work

[@travisshrewsbury7169]

I was waiting to get the shit scared out of me when it flew apart,damn good video Tom, I see Robin is paying attention

[@oaxelo1]

Very interesting. And yeah i was expecting that lockwasher/hook to deform more or even break.

[@jeffmoss26]

great video as always Tom!

[@Keith_Ward]

Great experiment Tom, I love things like this. I prototype things like your grinding wheel rack all the time. I usually start with CAD and move to paper or wood models before transition to metal. I typically use a box-in-box method when shipping items that are heavy or fragile so this seems like a good idea for folks who don't have the ability to fabricate or cut materials themselves. Folks who know how to pack a heavy box for shipping are a rare breed, tape and Styrofoam peanuts won't cut it.

[@dennyskerb4992]

Hey Tom, so much information craned into 30+ minutes. Luvin it. 👍👍

[@oxtoolco]

Wait a second. No smart assed answer from Dennis? Somebody must have hacked Dennis's account. Thanks for the comment. Cheers, Tom

[@keldsor]

Hi Tom ! I send you a little sketch of a proposal to the handle ;-)) Impressive that small eye-bolt you just made !

[@graffix90]

great idea with the box for the joints good old fashion duct tape plenty strong for the job.

[@scott_aero3915]

Nice work Tom, I was hoping you'd rise to the challenge! :)

[@FastEddie007007]

It is amazing how far you will go to satisfy your curiosity. Me, I just overbuild everything.

[@robgerrits4097]

Easy way to secure parts in boxes is to wrap them in bubble plastc, tape them closed and put in the box. Then use a little bit of expanding foam to connect everything, also to the sides of the box. Quick and cheap! Nice test you showed us, very unexpected to see. Keep them coming..thanks for sharing.:)

[@1pcfred]

The trouble with expanding foam is knowing precisely what that little bit is. People manage to blow their walls out with the stuff. So a cardboard box doesn't stand a chance.

[@matter9]

pretty neat! when you get more tech than just the straight up machine work, as the more specialized the work become the more interesting the tips IMO. Thanks for the video!

[@raycurren3639]

Hi tom. Love your vids and book. Can't tell how much I learned you mentioned truck bed liner for you disc holder. That stuff is very expensive. I would try rubberized undercoating. Good stuff at a fraction of cost. Thanks for sharing your knowledge.

[@Hunter333444]

Good video I'm always getting clever ideas from you I like the hex wrench and the removable vise idea is nice for a small vise . The wood inserts for a priority box would be very handy to have I have made quite a few of these myself and get very annoyed taking the time to do so Thank you ..greg

[@xull1x123]

i love this stuff, more practical testing please!

[@AmateurRedneckWorkshop]

Very interesting. I have sometimes out of necessity used fasteners that I thought were too small, who knows maybe they were just right. Keep on keeping on.

[@petek210]

Great video, as always. A simple tongue&groove joint with a friction fit might work for the boxes. Fast and easy to machine and possibly reusable.

[@bulletproofpepper2]

Great info. The web straps are like a spring and will store energy I would like to see you use a anchor point similar to your test block on the other end. Your web strap looks deferent then the ones I use. Thanks for sharing.

[@Hardturnin]

Nice idea to store the grinding wheels ours are in the drawer under the Grinder's working wheel in a space behind one storage door. It is full of wheels that do not like to stack up right. I like the liner idea yet to be honest if I wanted to ship such items as you have mentioned I would be inclined to make a wooden shipping box myself.

[@peterbaynes5804]

I enjoyed that Tom, a good range of content and entertaining as always... keep it up. The bolt test was interesting and informative... I realise there are all sorts of theoretical considerations and calculations but really a "practical" demonstration such as yours gives more than enough information and guidance for application in a home shop/hobbyist setting. I haven't been through all the comments but perhaps cable ties (zip ties) would work for the box in a box?

[@JohnRysdyk]

Pin nailer. for the boxes, used them till the glue set up, then couldn't remove them, had to cut them off. Worked wonders on my riding car build. 18 gauge nails 1.5 inches long. Plus you confirmed my choice of track bolts. Thanks

[@marcaitkin7653]

Great video Tom

[@rompdude]

Really cool seeing what a tiny bolt can yield! I had a faulty torque wrench a few years ago that managed to sheer 3 head bolts on my v8! Must have been some crazy force there. What i find interesting is how loads are spread out over surface areas to dramatically reduce the force.

[@Stephen1455]

The packaging idea is brilliant, you would be taking care of 2 problems, shipping and scrap.

[@Gary3247]

The simplest method for constructing the wooden box liners is to place the sides into the box & then glue or hot melt triangular strips into each corner. Very stable..

[@johnjohn-ed9qt]

For the box, maybe notch and key the edges if the boards, basically single finger finger joints. When asssembling, A strip of duck tape or fibre packing tape around each axis of the flat rate box would likely do the job. You could also kerf-key the edges (saw kerf normal to the surface, but with a but with a bottom at 45 deg to the surface) so when assembled, each edge gets a triangular key to support it. Tongue depressor stock works well for this. No glue needed, but much stronger if glued. One of two each edge should do. If the edges are straight cuts only (likely given your price point) it gets tougher.

[@wupme]

So if you apply one Tom to a long lever it can be converted to almost 0.4 Aboms

[@billlee5307]

Great Meatloaf! Shipping box inserts are a good idea. I wonder if they could be glued together quickly or even bonded to the box. Also thought that a cross wrap with filament tape might be enough to hold the pieces together and get them through USPS's package grinder. I like the file handles! I hope that Wesley will offer these for sale. I had to make a lot of parts out of phenolic and came to dislike the stuff. At the end of the day I would be itching and have skin reactions. It was like working with fiberglass insulation! Anyway, good luck with polishing it. Micro mesh is a great product. I very much enjoyed the 10-32 screw experiment. When you asked the question I thought that it was a hard one to give a single value for and expected that a range would be more realistic. Many thanks!

[@maxrunout2989]

Great, video, Tom. I enjoyed the analysis of the fastener preload. I have had to make box liners like that on occasion. They take time, and you never have just the right material. I would be happy to pay a few bucks to have them ready made. As to fasteners, nails are hard to beat, especially for a guy who has as many hammers as you.

[@armchairmachinist2416]

Yeee Meatloaf !!!! I'm happy :)))))) I was looking for info on KZbin about grinding wheels classification and what I could find was " there are two types of grinding wheels, aluminium oxide and carbide, in different grits" and that's about it. Since you have there a nice selection of wheels nicely coloured, and a book to, would be a good idea to beat this subject about grinding wheel types, colour coding and where and on what to use them on; something like , do I use a aluminium oxide wheel to grind aluminium? , what to use on HSS steel, what on cast iron .... and stuff like that. Nice set up to test the clamping load . Thanks. Bobby

[@samdevault7825]

I enjoyed the show Tom. By the way, I really liked the grinding wheel stand. I wish we'd had something similar in my tool grinding days. We used the peg board method and the wheels seemed to always be nasty when you picked one off the board. Of course 10 separate grinders put off a lot of airborne grit that has to land somewhere. Cheers, Sam.

[@mattym8]

Great stuff!

[@HolzMichel]

hi Tom your solution for the grinder wheels is a pretty good one. i would be so bold to suggest to use wood for the slotted part of the carrier. you run a risk of chipping the wheels on the steel when inserting them into the carrier. also if the carrier were to get an axial jolt, the steel can create a hairline fracture of the wheels that may not be visible. on your pull test, i wonder how much deflection that there was in the part where the screw head bit into the steel. Stefan Gotteswinter did a video on vise deflection and i did one as a follow up to see how much that a machine vise will deflect under an everyday workload. it was actually quite an eye opener. when the shim stock came out of the joint it may have been due to deflection of the part more than the screw actually stretching although that may have been a factor. one way to tell for sure would be to put the screw in a thread gauge (one of the tuning fork type). permanent deformation would manifest tself in the threads i would think. thanks for the food for thought cheers mike

[@droboepk26]

Quite a meatlicious episode, per usual! Very slick grinding wheel/arbor storage. Since it's going to live in a cabinet, what about mounting the rack on drawer slides? Or drawer slide cradle, so you could still take the whole rack out via handles. I always look forward to your next video!

[@JeffreyVastine]

Always a learning experience.

[@11zekim]

Great test Tom. I've sat through at least a dozen design reviews debating bolted vs. welded construction for ultra-rigid box structures, and it's surprising how often bolts win when the engineering is done correctly. Just to be safe, we usually sacrifice a summer intern or two for torque-testing anyway. You should see the biceps on some of these kids.

[@mg-shop6996]

Very interesting and with practical value.. May not satisfy theoretical engineers or lawyers, but for man-on-the-wrench utility this is useful. It's going in my notebook. Thanks! - M'G

[@classicrestoration]

Interesting test... I was waiting for it to go bang ;-) As for dial type torque wrenches, I find it more "bozo proof" to rotate the dial backwards, set it at the desired number and quit when you hit zero.

[@chemech]

Tom, Those wooden (plywood) box liners out to go together well with white or yellow carpenter's glue (Elmer's glue or equal) if they have rabetts or raceways such that they stack up and align. Adds a little bit to the production cost - additional saw or router passes to form the rabetts on the edges... The recipient can then use a wood chisel or a screwdriver to knock the box apart - or cut it with a saw... Your more sophisticated shipper can use staples from a pneumatic or electric gun instead to assemble the box. I almost did that to get a toolpost back to a guy after the Summer Bash... Cheers, Eric

[@oxtoolco]

Hi Eric, Glue would certainly improve things. I was hoping to make the box multi use or at least more than one. The cardboard would act as a glueing fixture but I don't think its reuse capability is very good compared to the liner. Stay tuned for the first test coming out on video. Thanks for the comment. Cheers, Tom

[@chemech]

Tom, Yep, glue tens to make things single use. Plywood tends to shred faster than solid wood, which also limits its multiple use capabilities in general... I'm looking forward to seeing what you've come up with - presumably a mechanical method of fastening? Cheers, Eric

[@bubbajoexxx]

great idea wood box liner for shipping

[@StraightThread]

Box insert kit is a good idea, in theory at least. It appears that the cut-offs from the wood place is Baltic Birch. It would be a good choice as it is very strong. However, joining the simple square edges together to form a rigid box that won't deform would be a bit tricky. As you said, machining any kind of joint on the edges would drive up costs, probably prohibitively high. Even just pre-drilling for nails or screws would add a good bit of labor. But, if you don't pre-drill, using nails or screws would be an exercise in futility. (I expect at least half who attempted nailing without pilot holes would destroy the box out of frustration before it even had the contents added by slamming it to the ground and jumping up and down on it. A glued joint alone wouldn't withstand much impact without some kind of mechanical joint. F-moulding that would probably work, but it would have to be cut to the proper lengths. Securing it to the wood with some kind of high-strength glue or perhaps with nails or screws (more drilling) would be one option. (www.extrude-a-trim.com/aluminum-extrusions/corner-moulding/18) Another option might be to use plastic banding with the F-moulding. A strap horizontally around the sides would probably hold the sides together. Then perhaps add the bottom, insert the contents, add the top and wrap two bands around the top to bottom perpendicular to each other. Finally put the box in the USPS box. That would make the inner container easily reusable. Of course a banding device of some sort would be necessary to seal the bands--another expense, but it, too, would be reusable and not a cost of a single box. Maybe it would be part of a start-up kit. For those who frequently ship the kind of stuff that needs the secondary box, it might be a justifiable expense. Just a thought.