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  1. #16
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    Isn't there a risk that the web will bend sideways when trying to straighten it?

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  3. #17
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    Quote Originally Posted by Karl Robbers View Post
    Why not just use your 50 x 50 x 5 hot rolled, cut your curve and the straighten the section. It shouldn't be that hard. Either using contra heating or mechanical means will work.
    Karl, in the age of cad water jet and bending roll machine you are proposing to use a hammer?

    I think that the legs can be made by stamping them with an industrial press into a purposely made mould, cut and bent in one go out of a 5mm sheet. A 10 ton press should be just the ticket.
    “We often contradict an opinion for no other reason
    than that we do not like the tone in which it is expressed.”

    Friedrich Nietzsche


  4. #18
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    Quote Originally Posted by Karl Robbers View Post
    Why not just use your 50 x 50 x 5 hot rolled, cut your curve and the straighten the section. It shouldn't be that hard. Either using contra heating or mechanical means will work.
    You are a mightier man than me! I mounted the piece between two bricks on the ground and gave it some attention with a sledgehammer. There was no noticeable movement.

  5. #19
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    Quote Originally Posted by Marc View Post
    Karl, in the age of cad water jet and bending roll machine you are proposing to use a hammer?

    I think that the legs can be made by stamping them with an industrial press into a purposely made mould, cut and bent in one go out of a 5mm sheet. A 10 ton press should be just the ticket.
    Yes, I am now discovering the wonders of designing sheet metal parts in Solidworks, and then sending them off for cutting and bending. Amazing stuff. This is the approach I'll take.

  6. #20
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    Quote Originally Posted by RustyArc View Post
    Isn't there a risk that the web will bend sideways when trying to straighten it?
    Seriously now ...
    If you have an angle that is bent, you can make it straight again just by using a hammer and an anvil. If the angle is bent away from the corner, you need to stretch the sides. A bit of hammering on the edge will make them longer and push the corner back in line. If the angle is bent the other way, you need to make the corner longer. For that you place the angle on the edge of the anvil and hammer the corner against it. This makes the corner longer and the angle straight again.

    If you have a forge or an oxy set, you can do this hot and leave almost no marks.
    “We often contradict an opinion for no other reason
    than that we do not like the tone in which it is expressed.”

    Friedrich Nietzsche


  7. #21
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    Quote Originally Posted by StevenManos View Post
    Yes, I am now discovering the wonders of designing sheet metal parts in Solidworks, and then sending them off for cutting and bending. Amazing stuff. This is the approach I'll take.
    Hu hu and I thought I was being sarcastic ...
    “We often contradict an opinion for no other reason
    than that we do not like the tone in which it is expressed.”

    Friedrich Nietzsche


  8. #22
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    Quote Originally Posted by Marc View Post
    Karl, in the age of cad water jet and bending roll machine you are proposing to use a hammer?

    I think that the legs can be made by stamping them with an industrial press into a purposely made mould, cut and bent in one go out of a 5mm sheet. A 10 ton press should be just the ticket.
    I'm a Boilermaker. We love all hammers big and small, although mainly big
    The use of hammers is an art rapidly being lost. If we think back to the good old blacksmiths, they had a hammer for every job, just the right size and shape. A big hammer pushes over a large area and a small hammer works more locally.
    All this CAD/CAM gear is nice, but for a one off job the set up costs usually far outweigh the advantages.
    I had the privilege of working in a workshop where we did everything from repairing or re pitching ships propellers to repairing rolled over aluminium semi tippers to panel beating and polishing fuel tanks, so have had a really good grounding on hammers and their capabilities from the 20 pound flogging hammer to the tiniest little ball pein. No wonder I'm half deaf.

  9. #23
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    Quote Originally Posted by Karl Robbers View Post
    I'm a Boilermaker. We love all hammers big and small, although mainly big No wonder I'm half deaf.
    Ahye? what did you say?


    If any one has seen the old time saw doctor finish a sawmill blade blade, its really an education. Just seeing the man straighten the blade with blows exactly where needed and to see the finished product was awesome to me.

    In general, hammer straightening is all about where to place the blow, how hard and how far apart your fulcrums are. The force of a blow would be all but dissipated on a couple of bricks.What is underneath the bricks is important too.

    Yes it is time and money now the skill and accompanying knowledge is all but lost from many manual jobs.I think places like this forum will be examined in the years to come for those seeking information and how to's on lost skills.

    Grahame

  10. #24
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    Quote Originally Posted by Grahame Collins View Post
    Ahye? what did you say?


    If any one has seen the old time saw doctor finish a sawmill blade blade, its really an education. Just seeing the man straighten the blade with blows exactly where needed and to see the finished product was awesome to me.

    In general, hammer straightening is all about where to place the blow, how hard and how far apart your fulcrums are. The force of a blow would be all but dissipated on a couple of bricks.What is underneath the bricks is important too.

    Yes it is time and money now the skill and accompanying knowledge is all but lost from many manual jobs.I think places like this forum will be examined in the years to come for those seeking information and how to's on lost skills.

    Grahame
    I had forgotten the saw doctor. A good friend of the family, sadly now deceased was a brilliant saw doctor. What he couldn't do with a saw, an anvil and a hammer wasn't worth doing.
    You are dead right, the old skills are being forgotten, although it seems that English wheels are coming back into vogue among the car fraternity. I remember one of my TAFE teachers making a metal bra from scratch out of sheet steel on the Pullmax, to this day it hangs on the wall behind his desk. While at first glance it is a frivolous project, it demonstrates all manner of shaping techniques and was very effective in capturing the attention of testosterone laden apprentices.
    I remember we had an AC Bristol car come into work to have a roll bar fitted, (which we were sure to do without hacking the car about), complete with hand beaten aluminium body. At the time it was valued on the high side of $160,000. To this day I am astounded by the finish of that car and the panel joints those craftsmen achieved. Workmanship that I doubt could be repeated in this age of whiz bang pulsing inverters and CNC wizardry.

  11. #25
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    So you both sort of captured my disappointment that the end result of a search into how to do something ends up in how to outsource something.

    I am glad however that some students still get to do things from scratch. My daughter is studying architecture and had to make up a small version of Theo Jansen's "Strandbeest"
    http://www.youtube.com/watch?v=HSKyHmjyrkA
    I helped her and I tell you it was a real challenge. No outsourcing nor cad crapping.

    The process of learning starts when the student is willing to listen because he or she thinks the other side has something of value to offer. The process of learning is blocked when the student thinks he/she knows better.
    A bit like the P platers on the road.
    “We often contradict an opinion for no other reason
    than that we do not like the tone in which it is expressed.”

    Friedrich Nietzsche


  12. #26
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    Quote Originally Posted by Marc View Post
    So you both sort of captured my disappointment that the end result of a search into how to do something ends up in how to outsource something.

    I am glad however that some students still get to do things from scratch. My daughter is studying architecture and had to make up a small version of Theo Jansen's "Strandbeest"
    http://www.youtube.com/watch?v=HSKyHmjyrkA
    I helped her and I tell you it was a real challenge. No outsourcing nor cad crapping.

    The process of learning starts when the student is willing to listen because he or she thinks the other side has something of value to offer. The process of learning is blocked when the student thinks he/she knows better.
    A bit like the P platers on the road.
    Very much.
    A good friend of mine undertook a furniture making and design course at the UTAS school of fine furniture. She was the only one to actually use traditional manual techniques, all the other students outsourced, using laser profile cutters and CNC routers. Very disappointing though was the general disrespect towards tradespeople shown by the lecturers. Peter Buchannan, one of the founders of the school, would spit chips were he still there, he was a trademan through and through.
    As far as I am concerned, those who only used CAD and CNC should not get a degree as they didn't even program the machines themselves.
    CAD/CAM should be an aid to manufacture, not the be all and end all.

  13. #27
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    Quote Originally Posted by Grahame Collins View Post
    Ahye? what did you say?


    Yes it is time and money now the skill and accompanying knowledge is all but lost from many manual jobs.I think places like this forum will be examined in the years to come for those seeking information and how to's on lost skills.

    Grahame
    That time is NOW.

    We have high school manual arts departments that are teaching design instead of skill.

    And in may industries tradsemen are being deliberately illiminated.

    They only want engineering and design grades and labourers.


    I am speaking with a number of still relativly young men like me in their early 50's..and they are all saying that the skills we where taught and drilled on, are not being taught now and have not been for several generations of so called " tradesman"

    We have 3 generations of tradesmen that can not manipulate simple basic tools and materials....and certainly do not grasp first principles.

    In the electronics industry we call them "the foxtel generation", semi-skilled labourers that have been trained to install one product and one way.

    If you want to see real skill and real art these days, you have to look to the retired and the amateur enthusiast.




    We band of brothers, we happy few, who learn and share on forums and practice in our own sheds are the only ones keeping these skills alive.

    But unfortunately, none will think themselves accurs'd they where not here with us, learning and sharing......because the buggers know so little, they don't know what they don't know.

    ( sorry went all shakspherian for a minute there)



    Seriously, there is stuff I have learned on forums that is simply not in the books or other sources currently available.

    Even the modern stuff.

    Back in the day, there where good books and manuals.....ANd I have one or two, all the important industrail processes where documented and explianed.

    But so much that is done these days..there is no record and no explanation.

    Some of the stuff Graham has posted, is as good as you will find in any book or manual.....if it was written down or commonly available.

    Sorry for the rant but that is the way it is.

    cheers
    Any thing with sharp teeth eats meat.
    Most powertools have sharp teeth.
    People are made of meat.
    Abrasives can be just as dangerous as a blade.....and 10 times more painfull.

  14. #28
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    So true and so sad.
    Imagine a wood or stone sculpture working for weeks on a piece and then another uploading a picture taken from the internet onto a 3d printer and spitting a piece out.

    Not all is bad though.
    I was thinking myself to get a cad plasma table to cut some profiles and then work them on the forge into 3d instead of just silhouettes.
    May or may not work, not sure, have not seen it done
    “We often contradict an opinion for no other reason
    than that we do not like the tone in which it is expressed.”

    Friedrich Nietzsche


  15. #29
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    Yeh they can't 3d print in stone or steel and mostly its pretty small.

    The thing that fascinates me is the obsession with CNC.

    There are a lost of people who have not been exposed to good trade practice who are keen on CNC.

    But the truth of the matter is, a lot of tasks, CNC simply provides no advantage.
    While there are some areas where CNC is prodidgeously effective...like engraving..., the old methods of repitition still work efficiently up to quite high volumes in many disciplines.

    As has been mentioned we have a very real problem where design is being taught before skill and materials science.

    So we have people tryng to design stuff that may not be able to be achieved or at least with difficulty.

    cheers
    Any thing with sharp teeth eats meat.
    Most powertools have sharp teeth.
    People are made of meat.
    Abrasives can be just as dangerous as a blade.....and 10 times more painfull.

  16. #30
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    And that clearly applies to the table in question. Without detracting from the value of the design itself, design has to go hand in had with feasibility. A bit like an architect designing a house that is like an inverted pyramid o top of a tree. Can it be done? perhaps by some magician, but what's the point if the designer does not know how to do it? or do we say, I am just a designer and am completely removed from the building process. Is there such a thing?
    “We often contradict an opinion for no other reason
    than that we do not like the tone in which it is expressed.”

    Friedrich Nietzsche


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