Hi Alex, I´m welding engineer and usually read and see lot of books and videos, but this serie that you made is outstanding! Best explanation ever. Congratulations!
As a person teaching myself welding, this series was immensely helpful. I greatly appreciate your thoroughness. There’s very few voices out there on the internet about how to solve challenges faced in creating in metal. Thank you very much for stepping out here and sharing your knowledge. 🙂
Really very helpful to understand the welding distortion and basic of the elements involved and how to handle it. Thanks Lot and Please continuous your posting.
It may take some time to spread around, but what you have covered in this series may become the standard for teaching designers and welders what goes on during fabrication. Good work, thank you!
This is easily the best explanation I've ever heard. Both the theory and the examples have helped me understand this in a way that I wish I had known 15 years ago. Looking forward to any future videos you have in store, because so far they've all been fantastic!
I second that. Was shocked by how much distortion the clamped piece had. Now it makes much more sense why my clamped tubing constructions were still warped quite badly after welding.
You combine theoretical consideration, with a scientific approach to practical experimentation, in a very effective manner! It is very clear why Stefan G. respected your work enough to recommend your videos. Many thanks for this very educational 4 part series. Cheers Paul in NZ
Fantastisch! Excellent and thorough series. After adopting the use of a Demmeler welding table in 2002, I've noticed that firmly clamping the work often results in the opposite of the desired distortion-free outcome. Now I finally know why! Vielen Dank Dr.-Ing. Fillafer.
Hi Alex. First of all thank you very much for affording your time doing this video series. I am a civil entineer with passion in metal works. I learned all my knowledge about turning, milling, welding and so on by reading and discussing in forums, watching DIY-youtube videos and reading books or articles. But your video about the well feared welding distortion is by far the most accurate and scientifical one I have seen to this topic. If you have some time left, a video about the different welding settings and the influences in distortion woudl be awesome. For example the frequency when welding (low or high Hz), the pulse settings (high current - short impact time or less current - longer impact time) and so on. Unfortunately I have not found a good source in explaining that yet. Tanks and greetings from Upper Austria. 😉
As Alex said, it is difficult to write up an "avoid distortion cookbook." Real life weld jobs are very diverse and weld conditons can put up constrains, limiting your possibilities. Nethertheless, Alex provides easy to understand insights into this topic. As already pointed by husq2100's comment, clamping can be done in such a way to pre-bend a part in the opposite direction (done that, works) and during cool down you can either wait until handwarm before opening the clamp or earlier to "correct" the degree of remaining bend. As Müller Mick mentioned, it would be good to cover sequence strategies (Pilgerschritt etc.) and aspects of infused energy (Streckenenergie etc.) in a subsequent video. Great content, esp. in times where the precentage of meaningful content and reasoning on the internet gets smaller :). Thanks for the very good work and greetings Stefan.
Great, Clear Explanation Alex. I see you have implemented your strategies in a clever way during designing and making your steel straight edge. Keep up with great applied engineering content.
Wonderful series. Engineer here, but this was very educational, and provided insights that were never covered during my studies. Thank you for doing this!
Thank you for making this series, I learned a lot. Prior to watching this I have had success using a tig welder to flame straighten by essential making a matching weld on back side of the metal. Now I know why that works. The negative effects of clamping while welding that you showed were enlightening. If you haven't seen them you should watch Dan Gelbarts series on making prototypes, they are also a mixture of theory and practical. Thanks to Stefan for sending me this way.
Hi Alex, big thanks for this series. It's a huge help for me as a welder/fabricator and makes my work much more fun and helps me make smarter constructions. And has already saved me tons of time and frustration. And its interesting too! If you're planning on doing more videos on this topic, i would like to hear you're thoughts on the influence of travel direction on a workpiece. Thanx and greetings from holland
Thank you sir for making such greatly prepared and organized videos for a topic thats hard to get clear explanation. Thanks alot again.. . All my respect 🙏🙏
Outstanding series. I'm trying to wrap my head around how clamping with the fixture table effects welding distortion. I can understand that if you heat up one side of the square bar in the center, the material becomes soft and expands. As you say, it's being constrained in x and y, but mobile in z. It makes sense that if the bar isnt free to move, there will be a greater expansion in z. but, for example, if you wanted to make a square frame out of square tubing with 45 degree joints, would fixturing it reduce distortion? Maybe because the joints are being connected together when by the filler metal when it is at its hottest (most expanded). There for the only distortion that happens is from the contraction of the joint. The fixturing constrains this and causes plastic deformation of the joint in favor of reducing welding distortion? I'm not sure
Thank you Alex for all your hard work in making this series I feel privileged to have experienced your findings. I only wish you could go one step forward and continue your studies, possibly combining all of the methods at one time.What is realistically possible ? for an example apply a pulse with back plates and then strategically welded . Or what ever method/ sequence you might do it in . Thank you again and sorry to beg of you for more information.
Finally made it to the last part.Your series really can be used as reference. All well explained and thought trough. Both for the beginner and expert, they all can learn something, refresh their knowledge and look at things at a different way. What I missed in this part was a closer look at welding strategies like "Pilgerschritt" (is that "pilgrim's step" in weld-speak?). Also a deeper look at "Streckenenergie" (energy per distance) or J/m. Comparing all methods (just by giving the numbers) would make more clear what a possible way of reducing distortion would be and what to expect. Comparing by energy of O/A, stick, TIG, and MIG, pulsed or continuous (can you demonstrate pulsed O/A?) would be interesting. Anyhow, despite my nitpicking ("Nickpicking" [tm]) truly woth watching and learning from!
Great series to learn about distortion, but it is only theoretical and the given practical examples are done on simple elements, not even a welded joint like in this part. When in actual manufacturing you can have large or difficult assemblys containing 10, 20 or more than 100 parts and many different welds, closed spaces, various part thickness. There will be no possibility to make a preheat for whole structure, nor use heat sink and the only available options are welding process and technique (like in your example pulse), clamps/jigs and weld sequence. That is the reason you can't find a book that will solve this problem and why there is many books with suggestions of using clamp/jigs and various welding sequences. What is shown in this series maybe could be aplied for manufacturing simple assemblys containg few parts and few welds. Trying to apply these methods in manufacturing of more difficult or large products would drasticly slow down manufacturing speed of the product and increase its price. In todays world everything must be done fast and as cheap as possible. Regarding the preheat method of the part, welding interpass temperature by most standards and handbooks is limited to 250C, so preheat to 300C is not acceptable. It would be not practical to preheat it to 150-200C either, because after few passes 250C would be reached and welder would have to make break and wait until it cools a bit before continuing, slowing the manufacturing process. My guess would be the lower the preheat temperature of the part, the less affect it will have on controling distortion. So yes it is nice in theory, but doesn't have much practical value.
Thank you for the video I'm about to start learn welding so this is awesome. One question though if I combined preheating and pulse welding will I reduce distortion even more?
Thank you for a very informative series. I have one question for you though, on the pre heated weld , after pre heating you placed the sample on the cold table, cooling the bottom to some extent. What would the result be if this was not done- less distortion ?
I have to ask you something Alex. When my uncle came home from the military. He taught me the in and out of welding. That time it was SMAW and Oxy-acetylene welding. Since that was many years ago and memory fades with time. He showed me the use of holding flux to help hold thin sheet metal which was stainless steel. I the name was Solar flux and using oxy-acetylene torch you could weld just beautifully and keep the sheet from turning into a pretzel. Would that method be another way of keep warp and distortion at bay ???? Peace
Hello Alex, Can I have your insight in residual stress in big machines such as CNC machines. I see many DIY makers make their CNC machines (even the one that is quite accurate) using welded frame and gantry. I always wonders if the residual stress really significant in such builds or it will creep up later and, say, bend the frame. Thank you and have a nice day!
Hello Thanh, thanks for your comment. From where are you writing to me? Good question you raise. The welding residual stresses are a concern unless they are relaxed by heat treating the welded parts. If no heat treatment is done, however, they are less of a concern if the welded parts are sized thick and beefy for the loads the machine will have to deal with. If, on the other hand, the parts are sized thin and lightweight, then the loads the machine puts onto them may raise stresses high enough so that residual stresses from welding plus stresses from machining loads together may cause the material to yield in large areas, causing the welded part to deform plastically. Hope this helps. All the best, Alex.
@@alexfillafer Hello Alex, thank you for your promt reply! Im writing to you from Vietnam, a tropical coastal country in South East Asia. Shared your vids to a bunch of my maker friends and they are all excited. Especially this series and the straightedge vid. We all appreciate the educational experience you offered! Back to the question, that was an ahh moment for me as this question had been bugging me for months. Among Cnc diyers we all know welding makes residual stress but still confused that many projects using weld still hold up great. In my case I am building an equivalent of an industrial Cnc router. Decided to avoid welding due to residual stress, just bolt + metal epoxy (to increase contact area) + rolling pin. But now I need to rethinking weld as it’s definitely stronger. I guess there is no way to quantify how thick is enough to avoid residual stress rather than, well, just try and see, or sized an as thick as possible steel tubes given that inaccuracy through time is a nightmare Thank you and have a nice day!
@@thanhnhanhuynhnguyen3652 Hello Thanh! No need to explain where Vietnam is, I've been lucky enough to visit your country twice, also Cambodia and Laos. I really like the kind nature of the people in south east Asia (and the food of course) and the way of life there. I know there are many downsides to life in your country as well, but I think your people's way of life is surely less "artificially" complicated than in western countries. Do you know Ca Lem? His videos I really like to watch, particularly the one of his tour through Vietnam. All the best and kind greetings, Alex.
@@anengineersfindings Dear Alex, sorry to take ages to reply. Our independence day was 11 days ago, big national holiday, which mean crazy work before that and crazy drinking during and after. I got caught up with all the vacation and drinking that I completely forgot to reply someone i admired. Im really glad to hear that you like our country (and the food of courses haha). Fortunate to visit Western countries sometimes, I have to say I agree with the term artificial. It was a culture shock to me when i came there. Regardless, they are great countries! I know Cà Lem (the name means ice cream in a cute and refreshing tone), it’s inspiring that he learned things by himself as well as he is (i think) the first famous youtube machinist that is Vietnamese. I love the tour too and did some by myself as well. Planned to record and put some of my enduro and road trip on in the future (well not the near future) Glad to talk to you! Wish you all the best Thanh nhan
Brilliant series amongst a whole lot of guesswork, myth and hearsay on this subject on t'tinternet. One slight disappointment. What happend if you combine preheat and heatsink with pulsed weld?
Not sure if he's just talkin or like speaking from a journal written screen or whatever but he has an accent and if that's just his old vocabulary man impressive using big words
I disagree with your comments on clamping/fixtures. It is proven and quite common to pre stress work piece to counteract the deformation caused by welding. If expansion is in 3 dimensions (X,Y,Z) and you restrain it in one dimension you can control deformation in that one direction. Restraining the work piece in more than one dimension would of course create problems that you have pointed out. I understand your experiment and appreciate it. But your clamping was not the way to counteract the distortion. You would normally pre stress the work piece with tension i.e place a shim under the centre of work piece to bow it up (opposite to what the welding will do) . This is also why you had troubles or not good success with the flame straightening with pie or wedge shaped heat zones. You must restrain the work piece for the heat to deform it (shrink) in the direction you require. There are plenty of videos on UA-cam showing huge deformation achieved on large structural beams with the wedge method. Sometimes the work piece is not restrained with clamps etc as they can use gravity instead,given the weight of the work piece. But it’s still a form of restraining.
Alex really enjoyed this series, Couple of questions regarding straightening solid round shafts about 25mm in diameter can you use a tig torch for heating or is that too focused a heat source and is rapid quenching beneficial to the process? Finally is there a formula to determine how much area needs to be heated verses degree of bend in the shaft?Thanks Zed
Here's a master of marine shaft straightening showing how he does it. He doesn't do the math, but it may be instructive to see someone who has been doing this for decades do a demonstration. ua-cam.com/video/MtnkkAzRgP0/v-deo.html Here's an older example of heat straightening shafts on the job. ua-cam.com/video/bOT4cSTJyqw/v-deo.html
Zed, to be honest I haven't seriously tried to use the TIG-torch for straightening, but if you can manage not to melt the workpiece surface it should work just as fine as the oxy-acetylene torch. Rapid quenching is not necessary for the straightening process. The whole purpose of watercooling is to keep the workpiece from gradually preheating and to allow for checking of workpiece geometry improvement (for this, the workpiece must have equalized temperature). I don't know of a formula to determine the necessary heated spot size and temperature, I assume there is none, because the straightening effect is a function of so many variables. Therefore, one usually places a moderately sized heated spot and after cooling checks geometry improvement. This gives a good feel for the size of the next heated spot to apply in order to (more or less gradually) attain the desired workpiece geometry.
Great content, thank you. The point of welding sequence is not very clear to me. At 17.10 you say welding sequence helps "actually no" and one sentence later you say it gives low distortion. Hmmm...
What I mean is that "welding sequence" is not a mechanism by itself, but rather a simultaneous combination of the aforementioned mechanisms to reduce welding distortion. Hope this answers your question.
what do you think will happen if it is tensioned clamp, like you put somethingin the middle of the clamping spots, and put a bit of tension on it, i often have the problem of bananification of pipes when welding on nipples along the pipe, for water nozzles, and preheating is maybe an option but it is stainless so prefferably not because then you have to polish/pickle the whole pipe
As an engineer and amateur welder, I found this whole series invaluable. Thank you very much for taking the time to make these videos.
God bless watching this in 2023 your still helping out years later first time watcher
Hi Alex, I´m welding engineer and usually read and see lot of books and videos, but this serie that you made is outstanding! Best explanation ever. Congratulations!
Hello Andre, wow, thank you so much!
As a person teaching myself welding, this series was immensely helpful. I greatly appreciate your thoroughness. There’s very few voices out there on the internet about how to solve challenges faced in creating in metal. Thank you very much for stepping out here and sharing your knowledge. 🙂
Thank you very much for your kind comment, Mr. Andersen. Glad if you find my content helpful.
@@anengineersfindings you are welcome! 🙂
Amazing videos man!! why have not more people seen this! UA-cam needs to sort out their algorithms!!
Really very helpful to understand the welding distortion and basic of the elements involved and how to handle it. Thanks Lot and Please continuous your posting.
This video answered a lot of question in my head about welding distortion.Excellent experiment..!
It may take some time to spread around, but what you have covered in this series may become the standard for teaching designers and welders what goes on during fabrication. Good work, thank you!
Thank you for your very kind words, Sir.
A really excellent series of films. Recommended for any fabricator, engineer or inspector. Thanks!
Many thanks, glad if you find it helpful. Cheers!
This is easily the best explanation I've ever heard.
Both the theory and the examples have helped me understand this in a way that I wish I had known 15 years ago.
Looking forward to any future videos you have in store, because so far they've all been fantastic!
Thank you Sir, glad to hear that you find the content informative.
I second that. Was shocked by how much distortion the clamped piece had. Now it makes much more sense why my clamped tubing constructions were still warped quite badly after welding.
Sehr gut strukturiert und sehr umfassend! Vielen Dank für Ihre Bemühung!
Fantastic series! It must have taken a huge amount of time and effort. Thank you very much!! Your explanations are very easy to understand.
What a great series! This has been very clear and educational.
You combine theoretical consideration, with a scientific approach to practical experimentation, in a very effective manner!
It is very clear why Stefan G. respected your work enough to recommend your videos.
Many thanks for this very educational 4 part series.
Cheers Paul in NZ
Thanks for watching, glad if you like the series!
THIS IS GREAT! I'm building bicycle frames and doing research on distortion. Thank you
Fantastisch! Excellent and thorough series. After adopting the use of a Demmeler welding table in 2002, I've noticed that firmly clamping the work often results in the opposite of the desired distortion-free outcome. Now I finally know why! Vielen Dank Dr.-Ing. Fillafer.
Glad you like the series, Sir!
Thanks mate, what a great series.
Hi Alex. First of all thank you very much for affording your time doing this video series. I am a civil entineer with passion in metal works. I learned all my knowledge about turning, milling, welding and so on by reading and discussing in forums, watching DIY-youtube videos and reading books or articles. But your video about the well feared welding distortion is by far the most accurate and scientifical one I have seen to this topic. If you have some time left, a video about the different welding settings and the influences in distortion woudl be awesome. For example the frequency when welding (low or high Hz), the pulse settings (high current - short impact time or less current - longer impact time) and so on. Unfortunately I have not found a good source in explaining that yet. Tanks and greetings from Upper Austria. 😉
Many thanks for your interesting comment, I'll think about your suggestion. ATB from Carinthia ;)
As Alex said, it is difficult to write up an "avoid distortion cookbook." Real life weld jobs are very diverse and weld conditons can put up constrains, limiting your possibilities. Nethertheless, Alex provides easy to understand insights into this topic. As already pointed by husq2100's comment, clamping can be done in such a way to pre-bend a part in the opposite direction (done that, works) and during cool down you can either wait until handwarm before opening the clamp or earlier to "correct" the degree of remaining bend. As Müller Mick mentioned, it would be good to cover sequence strategies (Pilgerschritt etc.) and aspects of infused energy (Streckenenergie etc.) in a subsequent video. Great content, esp. in times where the precentage of meaningful content and reasoning on the internet gets smaller :). Thanks for the very good work and greetings Stefan.
Alex, thank you for this amazing series!
Hi Roman, thanks, glad you find it helpful!
Great, Clear Explanation Alex.
I see you have implemented your strategies in a clever way during designing and making your steel straight edge.
Keep up with great applied engineering content.
Wonderful series. Engineer here, but this was very educational, and provided insights that were never covered during my studies. Thank you for doing this!
Thank you Sir, glad you find the series useful.
Thank you for this video series! EXCELLENT WORK.
Outstanding series.
Incredible series. I'll definitely rewatch it and try to learn more. Some of the best presented weld info I've ever seen.
Thank you for the effort.
Many thanks for your kind words, Mr. Lee. Glad if you find the content useful.
Great series! Best and most detailed explanation I've seen.
Thank you for making this series, I learned a lot. Prior to watching this I have had success using a tig welder to flame straighten by essential making a matching weld on back side of the metal. Now I know why that works. The negative effects of clamping while welding that you showed were enlightening. If you haven't seen them you should watch Dan Gelbarts series on making prototypes, they are also a mixture of theory and practical. Thanks to Stefan for sending me this way.
Thanks for your comment, glad if you find the content helpful. I already knew the Dan Gelbart series. Thanks.
Thank you. I really enjoyed this and learned a ton of new information.
Really, really good series, thank you!
Glad you find the series useful, many thanks.
Hi Alex, big thanks for this series. It's a huge help for me as a welder/fabricator and makes my work much more fun and helps me make smarter constructions. And has already saved me tons of time and frustration. And its interesting too! If you're planning on doing more videos on this topic, i would like to hear you're thoughts on the influence of travel direction on a workpiece.
Thanx and greetings from holland
Thank you for your encouraging comment, Sir. Glad if my videos are helpful. I'll try to think about your input on travel direction. Regards, Alex.
thanks for taking the time to prepare this video, very useful
Very informative. Thanks!
Thank you sir for making such greatly prepared and organized videos for a topic thats hard to get clear explanation.
Thanks alot again.. . All my respect 🙏🙏
Many thanks, glad you find the content useful.
Outstanding series. I'm trying to wrap my head around how clamping with the fixture table effects welding distortion. I can understand that if you heat up one side of the square bar in the center, the material becomes soft and expands. As you say, it's being constrained in x and y, but mobile in z. It makes sense that if the bar isnt free to move, there will be a greater expansion in z. but, for example, if you wanted to make a square frame out of square tubing with 45 degree joints, would fixturing it reduce distortion? Maybe because the joints are being connected together when by the filler metal when it is at its hottest (most expanded). There for the only distortion that happens is from the contraction of the joint. The fixturing constrains this and causes plastic deformation of the joint in favor of reducing welding distortion? I'm not sure
Bravo Alex! thnank you very much.
great video
Thank you Alex for all your hard work in making this series I feel privileged to have experienced your findings. I only wish you could go one step forward and continue your studies, possibly combining all of the methods at one time.What is realistically possible ? for an example apply a pulse with back plates and then strategically welded . Or what ever method/ sequence you might do it in . Thank you again and sorry to beg of you for more information.
Thank you Sir. I'll be thinking about your suggestions for a supplemental episode.
Finally made it to the last part.Your series really can be used as reference. All well explained and thought trough. Both for the beginner and expert, they all can learn something, refresh their knowledge and look at things at a different way.
What I missed in this part was a closer look at welding strategies like "Pilgerschritt" (is that "pilgrim's step" in weld-speak?).
Also a deeper look at "Streckenenergie" (energy per distance) or J/m. Comparing all methods (just by giving the numbers) would make more clear what a possible way of reducing distortion would be and what to expect. Comparing by energy of O/A, stick, TIG, and MIG, pulsed or continuous (can you demonstrate pulsed O/A?) would be interesting.
Anyhow, despite my nitpicking ("Nickpicking" [tm]) truly woth watching and learning from!
Thank you for your kind words, Nick.
I'll think about treating your suggestions in a supplemental episode.
All the best,
Fif
Great series to learn about distortion, but it is only theoretical and the given practical examples are done on simple elements, not even a welded joint like in this part. When in actual manufacturing you can have large or difficult assemblys containing 10, 20 or more than 100 parts and many different welds, closed spaces, various part thickness. There will be no possibility to make a preheat for whole structure, nor use heat sink and the only available options are welding process and technique (like in your example pulse), clamps/jigs and weld sequence. That is the reason you can't find a book that will solve this problem and why there is many books with suggestions of using clamp/jigs and various welding sequences. What is shown in this series maybe could be aplied for manufacturing simple assemblys containg few parts and few welds. Trying to apply these methods in manufacturing of more difficult or large products would drasticly slow down manufacturing speed of the product and increase its price. In todays world everything must be done fast and as cheap as possible. Regarding the preheat method of the part, welding interpass temperature by most standards and handbooks is limited to 250C, so preheat to 300C is not acceptable. It would be not practical to preheat it to 150-200C either, because after few passes 250C would be reached and welder would have to make break and wait until it cools a bit before continuing, slowing the manufacturing process. My guess would be the lower the preheat temperature of the part, the less affect it will have on controling distortion. So yes it is nice in theory, but doesn't have much practical value.
This has been very useful!
Glad to hear!
Thank you for the video I'm about to start learn welding so this is awesome. One question though if I combined preheating and pulse welding will I reduce distortion even more?
Excellent explanation!!!!
Thank you for a very informative series. I have one question for you though, on the pre heated weld , after pre heating you placed the sample on the cold table, cooling the bottom to some extent. What would the result be if this was not done- less distortion ?
I have to ask you something Alex. When my uncle came home from the military. He taught me the in and out of welding. That time it was SMAW and Oxy-acetylene welding. Since that was many years ago and memory fades with time. He showed me the use of holding flux to help hold thin sheet metal which was stainless steel. I the name was Solar flux and using oxy-acetylene torch you could weld just beautifully and keep the sheet from turning into a pretzel. Would that method be another way of keep warp and distortion at bay ???? Peace
Wow, very interesting, thanks for your interesting comment!
Hello Alex, Can I have your insight in residual stress in big machines such as CNC machines. I see many DIY makers make their CNC machines (even the one that is quite accurate) using welded frame and gantry. I always wonders if the residual stress really significant in such builds or it will creep up later and, say, bend the frame.
Thank you and have a nice day!
Hello Thanh, thanks for your comment. From where are you writing to me? Good question you raise. The welding residual stresses are a concern unless they are relaxed by heat treating the welded parts. If no heat treatment is done, however, they are less of a concern if the welded parts are sized thick and beefy for the loads the machine will have to deal with. If, on the other hand, the parts are sized thin and lightweight, then the loads the machine puts onto them may raise stresses high enough so that residual stresses from welding plus stresses from machining loads together may cause the material to yield in large areas, causing the welded part to deform plastically. Hope this helps. All the best, Alex.
@@alexfillafer
Hello Alex, thank you for your promt reply!
Im writing to you from Vietnam, a tropical coastal country in South East Asia. Shared your vids to a bunch of my maker friends and they are all excited. Especially this series and the straightedge vid. We all appreciate the educational experience you offered!
Back to the question, that was an ahh moment for me as this question had been bugging me for months. Among Cnc diyers we all know welding makes residual stress but still confused that many projects using weld still hold up great.
In my case I am building an equivalent of an industrial Cnc router. Decided to avoid welding due to residual stress, just bolt + metal epoxy (to increase contact area) + rolling pin. But now I need to rethinking weld as it’s definitely stronger.
I guess there is no way to quantify how thick is enough to avoid residual stress rather than, well, just try and see, or sized an as thick as possible steel tubes given that inaccuracy through time is a nightmare
Thank you and have a nice day!
@@thanhnhanhuynhnguyen3652 Hello Thanh! No need to explain where Vietnam is, I've been lucky enough to visit your country twice, also Cambodia and Laos. I really like the kind nature of the people in south east Asia (and the food of course) and the way of life there. I know there are many downsides to life in your country as well, but I think your people's way of life is surely less "artificially" complicated than in western countries. Do you know Ca Lem? His videos I really like to watch, particularly the one of his tour through Vietnam. All the best and kind greetings, Alex.
@@anengineersfindings
Dear Alex,
sorry to take ages to reply. Our independence day was 11 days ago, big national holiday, which mean crazy work before that and crazy drinking during and after. I got caught up with all the vacation and drinking that I completely forgot to reply someone i admired.
Im really glad to hear that you like our country (and the food of courses haha). Fortunate to visit Western countries sometimes, I have to say I agree with the term artificial. It was a culture shock to me when i came there. Regardless, they are great countries!
I know Cà Lem (the name means ice cream in a cute and refreshing tone), it’s inspiring that he learned things by himself as well as he is (i think) the first famous youtube machinist that is Vietnamese. I love the tour too and did some by myself as well. Planned to record and put some of my enduro and road trip on in the future (well not the near future)
Glad to talk to you! Wish you all the best
Thanh nhan
Hmm dont you weld two thin pieces with a tack, then lightly hammer the weld - to cool and flatten?
could you try pulse with heat sink to see if that reduces additively
Brilliant series amongst a whole lot of guesswork, myth and hearsay on this subject on t'tinternet.
One slight disappointment. What happend if you combine preheat and heatsink with pulsed weld?
Really surprised about the clamping one though I'm going to have a lot of trouble getting people to sign on to that want to work
Same here but I'm going to keep using that method because for me it works - in this video it did not
Not sure if he's just talkin or like speaking from a journal written screen or whatever but he has an accent and if that's just his old vocabulary man impressive using big words
I disagree with your comments on clamping/fixtures. It is proven and quite common to pre stress work piece to counteract the deformation caused by welding. If expansion is in 3 dimensions (X,Y,Z) and you restrain it in one dimension you can control deformation in that one direction. Restraining the work piece in more than one dimension would of course create problems that you have pointed out.
I understand your experiment and appreciate it. But your clamping was not the way to counteract the distortion. You would normally pre stress the work piece with tension i.e place a shim under the centre of work piece to bow it up (opposite to what the welding will do) . This is also why you had troubles or not good success with the flame straightening with pie or wedge shaped heat zones. You must restrain the work piece for the heat to deform it (shrink) in the direction you require. There are plenty of videos on UA-cam showing huge deformation achieved on large structural beams with the wedge method. Sometimes the work piece is not restrained with clamps etc as they can use gravity instead,given the weight of the work piece. But it’s still a form of restraining.
Alex really enjoyed this series, Couple of questions regarding straightening solid round shafts about 25mm in diameter can you use a tig torch for heating or is that too focused a heat source and is rapid quenching beneficial to the process? Finally is there a formula to determine how much area needs to be heated verses degree of bend in the shaft?Thanks Zed
Here's a master of marine shaft straightening showing how he does it. He doesn't do the math, but it may be instructive to see someone who has been doing this for decades do a demonstration. ua-cam.com/video/MtnkkAzRgP0/v-deo.html
Here's an older example of heat straightening shafts on the job. ua-cam.com/video/bOT4cSTJyqw/v-deo.html
Zed, to be honest I haven't seriously tried to use the TIG-torch for straightening, but if you can manage not to melt the workpiece surface it should work just as fine as the oxy-acetylene torch. Rapid quenching is not necessary for the straightening process. The whole purpose of watercooling is to keep the workpiece from gradually preheating and to allow for checking of workpiece geometry improvement (for this, the workpiece must have equalized temperature).
I don't know of a formula to determine the necessary heated spot size and temperature, I assume there is none, because the straightening effect is a function of so many variables. Therefore, one usually places a moderately sized heated spot and after cooling checks geometry improvement. This gives a good feel for the size of the next heated spot to apply in order to (more or less gradually) attain the desired workpiece geometry.
Thank you for adding these links, I really forgot to mention Keith Fenner as a reference for practical demonstrations.
Great content, thank you. The point of welding sequence is not very clear to me.
At 17.10 you say welding sequence helps "actually no" and one sentence later you say it gives low distortion.
Hmmm...
What I mean is that "welding sequence" is not a mechanism by itself, but rather a simultaneous combination of the aforementioned mechanisms to reduce welding distortion. Hope this answers your question.
@@anengineersfindings Thank you
what do you think will happen if it is tensioned clamp, like you put somethingin the middle of the clamping spots, and put a bit of tension on it,
i often have the problem of bananification of pipes when welding on nipples along the pipe, for water nozzles, and preheating is maybe an option but it is stainless so prefferably not because then you have to polish/pickle the whole pipe