marking-out steels and oxy-acet torch set-up - good?

Hi everyone
Following discussion in thread "Another simple weld that worked.", posted up a web-page showing techniques I know for fabricating in
steel
- marking-out accurately using a soapstone
- setting-up an oxy-acetylene torch
At
http://www.weldsmith.co.uk/tech/welding/oa_cutting/080825_markout_oacut_fab/080825_markout_oacut_fab.html
Has a lot of hand-drawn sketches and handwritten notes, as doing any other way would be more time-consuming than I could get around to.
Is useful?
Richard Smith
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Richard Smith wrote in sci.engr.joining.welding on 12 Nov 2010 21:52:06 +0000:

It is. But a little hard to read. Printing would be better than cursive.
--

Dan H.
northshore MA.
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snipped-for-privacy@privacy.net (dan) writes:

>http://www.weldsmith.co.uk/tech/welding/oa_cutting/080825_markout_oacut_fab/080825_markout_oacut_fab.html
OK. But if I am to do this I can't be "ploughing a lone furrow".
I am on an intense course at the moment and the effort would have to be slotted in over weeks, when "a change is as good as a rest".
Additionally point about "scanned cursive" - the text in the scans cannot be seen by a search engine. So someone searching for the knowledge with a search engine wouldn't see it
So if there is comment and what is helpful to present comes out as a concensus, I could do it.
A reality - the skill to the level shown enabled me to "fab. on site" - have the steel - beams, columns, plate - delivered direct from stockholder to site and fabricate the steel structurals there to measurements at site. Useful for doing changes to heavily twisted buildings - portal-frame buildings can be if bulldozers operate inside, for instance. So that every new structural must be made to the measurement of what is, not what the original drawing showed.
Even at the workshop, it seems often faster and more accurate to wheel the bottles to the stockyard than bring stock into the shop and saw. You get random error on flame-cut, whereas saw though very precise usually has systematic errors bigger and more of a pain than the random error of the hand-held torch-cut - eg. slant from the material not being truly square-on to the blade.
Richard S
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IMHO only, all suggestions with respect,
Word prcocessed text is not only much easier to read, it is also editable and easy to send or share electronically. I suspect that Weldsmith is a work in progress which will evolve with much editing and consolodation which will be much easier to do if your notes are done with a word processor at the outset.

Most artisans and tradesmen develop individual styles and techniques as part of their skill set. No one technique is always perfect for all situations or all people. An artisan needs to be versatile and possess a skill set large enough to accomplish the desired result and quality. They also need to learn to do quality work using a minimalists tool selection. Apprentices often have the biggest box of tools but an experienced artisan will usually accomplish more with fewer but more carefully chosen tools. This is especially true in the field or outside the shop. The fewer tools you need, the less you need to carry.
I do use the suggested marking technique of "approach direction to the 'true' edge", when working with wood or in some precision layouts, but when doing metal fabrication, I generally use the 'cut on the center of the line' technique. Most torch work is not done to extreme precision and fitup for welding usually requires some root gap, IMHE use of the "approach direction to the 'true' edge" technique usually results in oversized pieces that need excessive grinding to fit. It is usually easier and better to cut pieces for fabrication a little on the short side and then fill the gap with weld. It helps if your torch tip is the right size (no larger than required) and clean, and that your hand be very steady. When torch cutting, I find it a LOT easier to accurately follow the center of a line, than it is to find the edge of a soapstone line that is being blown or burned away.
I do not 'hollow grind' sharpen my soapstones, but that is mainly because I seldom have a wheel grinder closeby. I use flat soapstones which I sharpen on both sides (of both ends) using a flat file or the side of an angle grinder disk. I prefer the end curved. I usually break the sticks in half (pocket size) before use, and do not use any holder. YMMV, different strokes and all that.
I do not use your 'steady the torch with your thumb' technique, but you should use what works best for you. I prefer to steady my hands by touching my elbows but with very little weight on them so I can move them one at a time when making a long continuous cut. I can make a much longer continuous cut from my elbows than from my hands, a long torch also helps (and saves my gloves).
I do use several large carpenter's framing squares but seldom use a combination square or an engineer's square. I grind a fillet clearance on the inside and outside corners of the square so I can check for square over a fillet or an edge weld.
IMHO by far the handiest layout tool for both structural and pipe work is the Curve-O-Mark Contour Gauge. It makes layout of square or complex angle cuts on beams really easy. http://www.google.ca/search?q=curv-o-mark+contour+marker&ie=utf-8&oe=utf-8&aq=t&rls=org .
http://www.jrclassictrends.com.au/pages/contour/pages/stdcontourmarker.htm
some other neat pipe tools here http://www.lencocanada.com/pdf.d/800-05.pdf
I suspect that 'pug' is local usage, I have normally referred to a torch motor drive as a 'bug'.
I really like 'cutting machine torch tips as they are thin and have smaller than typical preheater flames. They do very fine work but require a steady hand or you will loose the cut.
IMHO, preheater flames are primarily required only for starting a cut, once the cut is established, they can be shut off and the cut continues just fine with O2 jet only. This is a common trade school demo. This trick works a lot easier using a cutting machine (or 'bug') and with very slow travel speed. I understand that some large operations shut off the preheaters on their cutting tables in order to save gas but I have not actually seen this done.
IMHO, Weldsmith is a good start and you should be congratulated and encouraged in your efforts. ISTM that there is a point on the learning curve where it is natural and helpful to write about what you are learning, it is a bit if a learning diary which could be helpful to others but will be gratifying for you to look back on in a few years, kind of like a student pilot logbook allows you to relive the exciting experience of learning.
Good luck, YMMV
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>>http://www.weldsmith.co.uk/tech/welding/oa_cutting/080825_markout_oacut_fab/080825_markout_oacut_fab.html
True
Not necessarily
Sometimes you need to let the thoughts flow. Working at the computer is too restrictive. You can't maintain purpose while occupied in time-consuming implementation. I was probably in a comfortable arm-chair, on a train or in a cafe, in a moment of relaxation, when I did those sketches. It makes premium time out of what could be dead time. I like travelling by train for that reason that it can be very valuable inspiration time. I sometimes tolerate a bit longer journey time and/or a bit higher cost in order to be granted that time instead of driving by car. I have to disagree with this point you make, for myself at least. The sketches and annotations capture something pure and complete as they poured out clear and simple.
You could take the inspiration and make a web-page which largely captured the idea. You'd not loose your way in the implmentation process.

True, this is my story. Only I can tell it.

The technique I describe certainly works for me. I was finding I was inside a millimetre (40thous) tolerance band. Given that when you wipe the cut with a 9inch angle-grinder you can lean a bit harder on regions your square has shown to be high.
I know exactly the issue you are saying about size. Jobs have "cut to nominal (accept + or - half the tolerance band)" or "definitely not over (-2mm +0 tolerance)". Never met the third possibility. Most structurals are "definitely not over". You probably couldn't force in a steel 0.5mm oversize, but bolts will get by elasticity a close-up on a -1mm +0 tolerance steel. Which I reckon I could work to. 1mm on say a 2.5metre steel is 1 part in 2500 - not a lot.

Indeed - I knew of as "bug" but stuck with local name. Would use that name if typed-out text.

Yes - it is a diary. You benefit yourself. Then you can get a message from someone saying how much it made a difference to them and how off the back of some success things took a turn for the better.
As I've benefitted in that way, it seems right to put back in.

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As I said previously snip

The only thing I would add/suggest would be filed under 'tools' and that is the laptop computer. We all have differing learning and creative styles, our task is to determine what is personally most effective. I suspect some of the newer and more compact 'pad' and 'netbook' computers may be better for some, but I still use a basic laptop as I do not need to learn new programs and the data is easily transferred to my desk unit. I also do lots of sketching for concept and design, and like pencil and paper as a thinking aid..

agreed
snip
Also agreed, with the added bonus of additional learning in the process. This sharing and learning is the main reason most of us are here on sejw.

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way too hard for me to read. Sorry.
--
~~~~~~~~~~~~~~~~~~~~
DanG
Keep the whole world singing . . .
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Thought I was the only one.
Steve
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OK folks - seems like it needs text typed and the illustrations only kept as .jpg
Can't promise to do that any time soon, unfortunately
Richard S
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