Brazed aluminium joint strength test
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- Опубліковано 15 жов 2015
- Testing some of David Picchiuto's brazed aluminium joints
woodgears.ca/joint_strength/br...
David's videos on this:
Strength test: • Aluminum Soldering Str...
Coffee table: • Easy to Make Coffee Ta...
Brazing technique: • How to "Weld" Aluminum... - Навчання та стиль
This was fantastic! These testing videos are some of my very favorites on your channel!
Enjoyable and highly informative.....we expect nothing less but we always get so much more.
Thank you Matthias!
Great video, I'm so glad you did this. I enjoyed David Picchiuto's original video as well, and was curious about the strength of the joints with different forces applied. Questions answered, without even asking! Thanks!
Love you guys. You so quickly and effectively jig and test and quantify the answers to my questions. You save me so much time.
These load test videos are super informative- thank you for making them!
This cross-over-collaboration-follow-up thing Is great.
Thank you for doing this! I always enjoy your methods!
+Make Something 600lbs sheer ought to be enough for anybody!
+Bradley Weingartner I would agree! Success!
+Bradley Weingartner except none of those joints have any sheer force applied to them in that table design.
You're right, they basically have no force applied to them.
Got rekt
I am wanting to braze aluminum for a project, I found this very informative! Thank you again, I always get your vids in my feed and love it. Subscribed.
I love seeing crossover videos like this. It's awesome to see that my favorite youtubists are all one big community of makers
So, for my application of an aluminum air duct joint the brazed joint will work just fine! Thank you for a great test and video!
Great video. Glad you did the quick M+T test in oak at the end as I think it was really good to show the comparison to wood.
Gotta love well made tests! Great video Matthias!
Mathias just scienced the SHIT out of that.
+Aaron Canaday You have gained 1 nerd point for your The Martian reference.
Great to see this kind of collaboration! Thanks for sharing!
Nice work. Love your strength test stuff. No one else does it so keep at it. Make it your own.
I had been waiting for this video. Very cool to see the results.
love to see the friendly co-operation between you tubers , not competition, now I have another person to subscribe to (make something) , because they worked together, looks like another cool channel
I love these collaborations! Thanks Matthias!
That table jump test was hilarious! Another great video
Dig the collaboration and the test both! Good on you both.
love the strength tests! I was hoping you 2 might get together on this.
beware all builders. if you dont use wood, Mathias will come and break your stuff!
I think you've found a great niche Matthias. Your thorough review and explanation are very interesting and show a larger spectrum of understanding that we may generally write off. I may still use braising for low bend moderate sheer applications but upgrade to Tig or switch to wood joinery if resilience is a concern. I'm sure David got a kick out of the tests, it pretty much represents his expectations.
I heard the bathroom scale called the suicide hotline ... Saying something about always being pressured into breaking joints.
+Heavyboxes Well, at least this time I didn't bend the scale, like last time.
I really enjoying these strength tests
I enjoyed your testing procedure, but I'm sure David's table will give him many years of service.
Your explanations are excellent. Thanks!
Oh man , you are a Wizard of All. I enjoy every video. Thanks
Thanks Matt. Another thought-provoking session. After your video, UA-cam automatically started another video on a similar subject but I had to turn it off because I found the so-called background music distracting and annoying. So many thanks for not putting music on your videos; well done you.
Matthias, I really enjoy your videos. Thanks for the education!
These strength test videos always make me laugh. You know it's coming but it's still a surprise.
Love the crossover videos, keep 'em coming!
As interesting contribution and scientific system for aluminum welding David, thank you very much for uploading the video.
Great testing technique! Very smart dude
Excellent video, sir.
i like your testing mechanisms, thank you
Great test! Really informative. Thanks.
As usual a great video, instructive and interesting.
Holy crap, your camera quality is amazing!
I want to use this method of brazing aluminium to make a shooting rest for the front of a quad bike. At first I was worried that it might not be strong enough but after watching this I don't have any concerns. Thanks for making the video.
you should have no concerns about the fact that his connection will not suffice. In fact, the coffee table that David Picciuto built also broke.
Loving the funny bits in every video!
If anyone is curious... the yield moment strength of the aluminum tubing used is roughly 507 in-lbs. In most welding applications, you can typically get a welded joint stronger than the base material. I don't think that applies to brazed joints though. Anyway, the load applied by Matthias was roughly 195 in-lbs. Approximately 38% of the strength of the tubing.
2:55 AvE would call this "asking for summer teeth"
+Kevin Klika Lol, Good one! I cringed every time he leaned over the support peice to read the scale
+Kevin Klika yikes! didn't notice that before.
+Kevin Klika HaHaHa... the man is a linguistic genius!
Ingenius testing apparatus. Very informative.
awesome testing
If you add a fixed sized checker board pattern behind this type of device, the audience would better see smaller movements compared to a blank white wall. Just a suggestion.
Love these test videos
excellent well detailed video! precise and to the point. what happened to the screw jack?
Nice attention to setup detail.
+Matthias Wandel I'd be happy to TIG some tubing together and send it if you wanted to compare.
This would be a great follow up. I'd love to see the results
+Jason Toews Sure. Send me two samples. I'll only promise to do the bend test though. Might be too strong for shear with my apparatus. The tubing is 3/4" x 3/4", not too much wall thickness.
+Matthias Wandel would be interested to see how TIG compares to other types of welding methods....
@Matthias Wandel: For this kind of joint, you are measuring maximum moment of force. Force itself does not mean much. You have proved by breaking T sample using two levers and little finger. So again: Both measures measure same thing. Just multiply result by length of the lever. Moreover, for any construction using this joints, it is the maximum momentum of force that is needed not be known. Just not to use it for too large constructions without some additional reinforcement.
We have a destructive testing facility at the university I work for...I'd be willing to bet that someone there is familiar with this channel!
i saw that and wanted to recommend it to you but like alot of americans i just got lazy and forgot but im glad you did this great video matthias
Great video Matthias! You had that thing with Steve Ramsey and now your picking on David... Question who is next! LOL! Wish I had just a molecule of your know how.. Looking forward to your next video no matter the subject!
Matthias, you are so ruthless xD I almost feel sorry for David... But again, very clean and clever testing!
+Grigoriy Yavlinskiy (Ergo Proxy) I know, right? I'm surprised my coffee table hasn't killed someone yet or worse, a pet! You did stick around and watch his conclusion at the end, correct?
I don't think ruthless is the correct word. Matthias is thorough and did a great job at proving David's assumptions and explaining expectations. Matthias is certainly the man to do this testing. His care and attention to detail combined with sound logic and explanation does make him a great impartial reviewer.
+Jason Harwell That's true, but in all honesty, the "little finger" test was a bit of a misnomer...yes, he could break the joint with his little finger, but he failed to emphasize that he was multiplying the leverage applied by the length of the two added extensions....if it withstood 40 lbs of force 3" from the joint.....with the 24" extensions he was actually applying 320 lbs of force with his little finger....ah the magic of levers....even on the testing rig, 40 lbs of force applied 3" from the joint is still 120 lbs.....to be accurate, he should have applied the 40 lbs AT the joint....without benefit of the restraints....to allow the welded arm to "bend" and that would give him the bending force at "close to zero" then he could extrapolate from there.....
So, the joint is perfectly acceptable as in the coffee table, there were 4 joints in both directions so it could easily withstand 320 lbs of lateral force.....kind of like if two of your buddies decided to ride it down the street....
BTW: would I reccommend these methods for building an aluminum trailer? definitely not....for a coffee table, or general uses around the house? Definitely.....
Make Something Sure, just joking, dont take my words seriously. By the way, i liked your cofee table, especially lifting mechanism.
Grigoriy Yavlinskiy and don't forget: no matter what you do, there will always be someone out there showing how you're wrong...
I recently got into casting aluminum and learned a lot by a guy called myfordboy, incredible amount of info and videos and of course, there's some knob making videos on how his methods are incorrect.....
6:50 Wow that really made me laugh. Totally unexpected. Keep up the great videos; they are always very entertaining and informative. *thumbs up*
Very nice experiment. I think it's great David sent the samples...nice collaboration. I had to laugh when you said you didn't have the patience to braze the joints...coming from a man who has enough patience to methodically design and creat some of the most intricate and complicated devices (slinky machine, pantorouter build, pager rotating machine, etc. ) that must have taken days or weeks of planning and work to accomplish! :)
I love UA-cam. You guys are awesome! Thanks for the Information!
If it's not strong enough, you can still reinforce it with a gusset plate and some rivets to reduce bending forces. It will make for a less extreme ratio of lever lengthes because the short lever is no longer limited by the diameter of your aluminium profile.
good demonstration.
Good experiment and good to know. it'd be interesting to see how strong the plastic press fit joiners are for that aluminium tube
now for the real question how much would a little triangle piece reinforce the joint.
A lot
L bracket and a couple rivets. Done
Good point.
Gussets are amazing!
Great video, u spun me how u think up this stuff
lol you answered all my questions about the aluminum brazing joints, and i did not even do the RnD on it , tks ,
tig it is
The lever action is actually applying more force to the joint the further out you apply it. Less movement, more force applied with less weight, so the weight applied to the joint is much more than at the point you applied it. Wood does a bit of bend don't break, so it has an advantage over metal in that way.
that's actually true, he didn't calculate the true force based on the lever arm. he was 10cm out, which means it still took about 400lbs to break it
I like this partnering to do experiments on stuff like this, really informative and professional video as always Matthias. only this is tig welding aluminum is not at all easy if a recall, this "alumabraze" seems to be more approachable as you aren't going to have to worry about burning a hole, then again i have never tried this. Ps: at least it beats pocket holes...
I really love these kind of videos. They're cool and fun to watch, but more importantly, they give you an idea of where you stand as far as failure points.
One thing I'd like to suggest though...when ever you do these, maybe have an exact distance out from the point of failure you're testing. I mean if you go out one FOOT, then we know FOOT POUNDS of torque that's being applied or one INCH for INCH POUNDS being applied.
Of course you can do the same thing for the metric system and it's easy enough for us to convert as long as we stay within common even lengths. I think you said you're at 11cm and that's not even a half a foot, so converting to foot pounds or anything else is difficult. I know you don't make these, I'm just suggesting for future tests. In any case, keep up the great work.
+wjf213 Read the corresponding article.
Matthias, I wonder if you can see any brazing material between the full contact area because when David showed how to braze he clamped the pieces together tightly. But as far as I know you should leave a gap for about 0.1 to 0.3mm for the braze to yield into that gap. If it can´t then there would have been only the braze inside the bevel which holded the pieces together.
Matthias,
I like a lot of the comments below and would like to add that you're a great teacher.
If I may recommend a future video -- There are many "how to" videos on homemade bicycle generators, but I have yet to see one explained clearly enough for us non-engineers. Building one looks easy enough......how it works properly is still elusive. One of the videos used a washing machine motor. I don't understand how we get a motor designed for AC to charge DC car batteries. The "why" is always missing in those explanations. I have taken freshman level EE, but can you please help us understand the details?
Love your videos. The internet is the world's biggest library. Sure, there are the red light districts, but there is also so much information, that anyone with access can learn anything they want. Your explanation of bending moments can be used to explain why trusses are used in roof construction. Kinda hard to apply a bending moment to a triangle.
Looking forward to your future work.
Thanks,
John
0:38 ... hahaha love that you included the "pop" noise, that made me crack up ... dunno why XD
+Benjamin “Ozias” Esposti Such a satisfying pop
Slynk Yes!
I don't know why.. it just is! XD
Would like to see a test of glue joints to see the relative strength of 1. face grain to face grain joint; 2. end grain to end grain joint; 3 miter joint. Other angles between zero and 45 might be interesting to see the strength curve over the various angles.
We're also talking square face to a plane. I bet that a bit more could be squeezed out from various configurations. But, hey, for a coffee table, it's better than some IKEA products.
I've had better luck pre heating aluminum in oven before using propane. always enjoy your tests
I love your tests. I worry about your safety.
actually people suggested to test the bending force on his channel. nice collab though, thumbs up!
This is great. thank you
I'd love to see you do a pull strength test on nitinol springs!
I would suggest the strength of the aluminum joint is only as good as the preparation & which aluminum weld rod was used. Project Farm has done a comparison of the assorted welding rods available & there is quite a range in the success of the test results.
Cool testing, it would be nice to see how brazed aluminium holds up to a fatigue test, I imagine not so well. The force measured for failure with a bending moment would probably be better as Nm or Lbft, measured as torque, I guess that would help with design anyway.
Great video ... reminds me of my Mechanics of Materials labs.
His table will never fail because of weight. It could only possibly fail because of a lateral downward force applied. The table is still supported by vertical tubing on end. Which is really strong. The brazed horizontal pieces are really only lateral supports.
Aluminum brazing is very tricky, especially joints. Because you usually end up melting what you just brazed when trying to heat the piece around the other side to finish up the weld.
MiG Welding Aluminum is way easier. TiG requires patience and extreme dexterity, but it's not hard once you learn to recognize what to do and when. But if you really wanted a project like this, there's nothing wrong with taking your aluminum (cleaned bright) down to a real welder for $50. This whole DIY culture kinda leaves out helping your local community, by supporting other artisans.
Metal joints of the most basic quality rarely fail under static loads as you're testing. The vast majority of failures occur under a dynamic load, and it's often a very mechanism.
The testing would be more complex, but more along the lines of real-world conditions.
Anyway, nice video.
I think the issue isnt as much the material or method of combining it, its the structure of the joint itself. Since the bar is only attached along its end and to the face of the other bar, when you apply a torque like Matthias was calling a bending moment, the lever arm for the joint to counter that torque is tiny and just like his testing apparatus scales down the force on the scale, the joint scales up the force immensely, which is why 45 pounds could break apart a well braised joint
I've been doing some research on these aluminum "brazing" rods. First and foremost-- with a melting temp of only 700-750° F (370-400° C), this isn't true brazing-- it's technically soldering. According to the American Welding Society, brazing uses filler material with a melting temp of 840" F (450° C) or higher. That may be overly technical, but for someone like myself who is trying to understand the full potential of it, it's important.
Secondly, everything I've seen thus far makes it clear that creating a solid joint is a bit tricky-- you have to be able to get the filler material to bond with the aluminum and not the oxide layer that always forms on the surface. Prep is key, but you also need to scrape through the melted, liquid filler material to break up that oxide layer. +Mattias Wandel, that may have been why you weren't able to get a good bond.
Very good video! I am encouraged and plan to try this myself!
I honestly think the wood comparison is the most telling of everything. If you look at many traditional chairs (Windsor in particular) they are made up predominantly of mortise and tenon joints with smaller contact areas than what you had in your wooden test joint. Those chair frames fair well enough, and likely have strengths comparable to the weakest of the brazed joints you tested.
Aluminum brazing can be super strong, but it requires proper prepping. The brazed area should be free of any contaminants with as little oxides as possible on the surface. Thus, you need to abrade the surface to remove the thin layer of aluminum oxide, which forms again very quickly. You need to follow it up very quickly with acetone or brake cleaner to remove any grease or other contaminants. For the best results, you need a rod with flux or use a flux paste for aluminum.
I would love to see the same tests with some tig and even mig welded joints for comparison. Would be great if someone offered to send you some! (I would, but don't have the gear). Perhaps we should ask Colin Furze? Now that would be a GREAT crossover!
Very interesting Test! Did you ever hear of the XYZ Spaceframe Bicycles? they too use aluminium tubing and are put together only with nuts and bolts. NO wielding. maybe you use that xyz-spaceframe-idea for some more testing in the future.
Flying leap sounds fun.... David? LOL! It surprised me that the wood M&T joint didn't do much better than the 40lbs the aluminum did...I thought it would hold up much better. Well good to know.
Joint strength aside, the lift up top at the very end is a great idea!
+radbot1 You can buy coffee tables like that, so it's not really novel.
and honestly, you shouldn't need that in a coffee table. Get off the damn couch.
+seigeengine So I guess one can't relax on the couch editing video after a long day in the shop? I'm sure you weren't sitting when you typed that, right? RIGHT?!?
Colby Ruffing Apparently reading is too hard for some people.
+seigeengine Seemingly, not being a fight seeking troll is too hard for others.
These videos tend to have a very sensible audience which causes little to no trouble. But rest assured, there is ALWAYS one.
It would be interesting to see the strength difference between alu welded joint and alu- plastic connect-it fittings.
Some pocket holes would strengthen those brazed aluminum joints.
Lotus Elise aluminium chassis uses glued joints no welding or brazing at all.
Lotus Elise - The Inside Story 31 mins in for testing welded versus glued joints
“Give me a place to stand, and a lever long enough, and I will move the world. ” ― Archimedes
Would it be possible or practical to fasten a bungee cord (or some other rope) to the test piece, fastened to the work bench, so if/when a test breaks, it is pulled away from you rather than potentially towards you?
Interesting test! Someone did similar test comparing aluminum brazing and wooden joints, video is under the name "Aluminum Brazing Demo & Strength Test - Spoiler Alert: FAIL!
", and wooden joints (he used softwood) of the same geometry was significantly stronger. I wonder if the difference was in the quality of brazing in his test samples, or perhaps the fact that he did not use mortise and tenon joints but half-lap joints.
Finally understood in a practical way SF and BM where it can be applied to real world situations. Studying civil engineering and for some reason woodworking makes it easier to understand the concepts with the help of +Mathias Wandel
Thank you.
Not an expert but as with wood joints destination of brazed joint is critical, as the strength it in shear some kind of lap or something joint I believe is best rather than butt joints. Cool tests.
impressive methodology
i rephrase. excellent!