Scaffolder to Scaffold Designer

AOM,

Cheers mate.. the sample drawings on there are just to give you an idea of what to expect if you employ us to design scaffold for you, I'm glad you can read them!! Must be doing something right! But in all seriousness, I firmly believe in making the drawings as easy to understand as possible, all the detail, all the notes, but still easy to read so I appreciate your comments mate.

As for CADs Draw.. I've never used it. I have seen what it produces tho in their demo when we were looking at Scia. If you want to produce professional drawings of complex scaffolding I personally don't think its capable, there is no comparison to AutoCAD. If you just want to do independents and birdcages and straight forward stuff I guess it's fine. I suppose you need to ask yourself what you really want to get out of it..? I'm not sure how you would go about modeling a station roof or viaduct or something.

CADS software is good tho for the right applications, I have used Analyse 3D and thats pretty good.

B.
 
I know it will be a totally different animal to what you guy's would need but what annoys me is needing calculations for a 4m span on a 3 lift independent. I am sorry if that is your bread and butter but I think it's way over the top although between yourself and Alan I know understand why I can't get generic drawings and calcs done so every day is a school day. We use the Cads stuff just to illistrate what we intend to build and to prove we don't need design with the TG20 checker but as you and everyone else is only too aware it only covers a very small number of jobs and I have been thinking of having a closer look at this thing.
 
Aom have you ever had a job collapse because you put it up wrong ?

exactly , this TG20 rubbish and all this design every job cr ap ( no offence designers)
has got everyone questioning what they know is right , we need to get the idiots out of our game and go back to letting us do what we are good at. Dont get me wrong there will always be jobs that will need to be designed ( there always has been) , but when you gotta get a drawing to do a 40 foot high tower then what have we been doing courses and serving our time for all these years ?
 
philliosmaximus said:
Aom have you ever had a job collapse because you put it up wrong ?

exactly , this TG20 rubbish and all this design every job cr ap ( no offence designers)
has got everyone questioning what they know is right , we need to get the idiots out of our game and go back to letting us do what we are good at. Dont get me wrong there will always be jobs that will need to be designed ( there always has been) , but when you gotta get a drawing to do a 40 foot high tower then what have we been doing courses and serving our time for all these years ?
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well said phil, we need to put this to NASC to revise TG20 and get a bit of common sense back into the game.Bin the EU too they are not helping things.
 
Agree guys, The Government commisioned Lord Young to review, and recommend changes to our current practice regarding the implementation of our H&S laws, without interfering with our HASAW 74.

The 'Common sense approach 'to H&S was a major recommendation, however, if your a H&S guy, are you going to let that stop you from 'Justifying 'your major role or undertaking in the company concerned, without being a pain in the Arse, Conkers bonkers = Mortgage and food.

We all have to make a living guys, however, some like to try and feck it up for us.
 
Gentlemen.. I feel I need to make this point.

For the last 20 years you have been erecting scaffold to 5973. 5973 said every special scaffold listed in the back sections should be designed. They never were. The scope for non-designed scaffolds was smaller than in TG20. TG20 actually gives you more options for non-designed scaffolds and the later special scaffolds sections are taken straight from 5973. The difference is not that TG20 has suddenly meant you all need designs, the difference is that now clients/contractors enforce the use of the correct codes. Therefore you need to get designs done for everything that is not 'basic' as the current code of practice is BS EN 12811-1 (therefore TG20) or BS 5975. TG20 states all non-basic scaffolds must be designed. This is nothing new, it is the enforcement of the code and the clients awareness of it that is new.

This is a result of a few things.
1. The focus on H&S over the last 10 years and its importance within the work place.
2. The enforcement of CDM regulations
3. The blame culture that has developed over the last 10 years - by that I mean, injury = claim for compensation meaning everyone must cover their ass and not take any responsibility... sorry, avoid as much responsibility as possible.

I am not saying you are wrong, I agree with a lot of the things you say ESPECIALLY the application of common sense for experienced/proven ability, but I must make this point. It is the way that all construction will go from now on and it will be a case of embrace it or do something else.

B
 
Phil, as ever you make a great argument and your right I have never had one come down that wasn't put up right but I do remember a situation when I first started out a 30 tonne front end loader did a lot of damage and there were some intense questions to be answered from the following investigation. That's why I advocate pictures and paper work to cover your back sides as I learned a lot from that time and am glad to report we were finally exonerated but still got shafted from insurance firm as they knew I didn't have the resources to chase them through the courts for my losses.

That's the main reason I feel BMB has made a good point and I for one decided to embrace it and invest in all sorts of daft stuff I know we don't need. As BMB has mentioned there is a far greater awareness of regulations but when I am asked to prove if the 9' span over a garden shed on a 3 lift independent I do shake my head but I also no they are technically entitled to ask and expect an answer, hence the dilemma draw it or pay for it. I would love to scribble a couple of calcs on the back of a fag packet but we all know that aint happening.:embarrest:
 
BMB said:
AOM,

As Alan says, its the application that is key... knowing how to analyse beams & ledgers say, how to arrange the scaffolding to suit the situation ( eg. minimising bending moments or support reactions) and then correct assessment of load cases.. but I really am just scratching the surface there.

Anyways, a quick google search later and I found this .pdf document: http://www.awc.org/pdf/DA6-BeamFormulas.pdf

Its for timber beam applications but the formula are relevant to any situation.

B.
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Nice attachment B.
this makes it all much easier to understand LOL
regards
Alan

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philliosmaximus said:
Aom have you ever had a job collapse because you put it up wrong ?

exactly , this TG20 rubbish and all this design every job cr ap ( no offence designers)
has got everyone questioning what they know is right , we need to get the idiots out of our game and go back to letting us do what we are good at. Dont get me wrong there will always be jobs that will need to be designed ( there always has been) , but when you gotta get a drawing to do a 40 foot high tower then what have we been doing courses and serving our time for all these years ?
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Morning Phill,
In a later post BMB makes the point with regards these regulations have been in place since the introduction of 5973, he is absolutely correct. There were changes in the original version of TG20 which have since been removed BUT the regs have always been there just seldom enforced.

As an observation:
a job that has not fallen down seldom tells you how close it was to falling.
The erector may never know the outcome of a scaffold being loaded to its design loading. What if the wind had blown a little harder.

Walking across the M25 with your eyes closed and making it to the other side is not a clear statement that you will always make it.

Designed or non designed scaffolds are trickey subjects, Scaffolders doing enough to get paid and move on, Engineers missing bits off a design to get it off the board, (yes I do go back that far) neither of which are acceptable may not in themselves cause the problem but combined and then multiplied by the end users lack of knowledge by taking out ties and removing the odd ledger here and there this is where the problems may be exposed.
You are not erecting scaffolds to stand by themselves you are erecting scaffolds to withstand the idiots who use them.
regards
Alan

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aom said:
Phil, as ever you make a great argument and your right I have never had one come down that wasn't put up right but I do remember a situation when I first started out a 30 tonne front end loader did a lot of damage and there were some intense questions to be answered from the following investigation. That's why I advocate pictures and paper work to cover your back sides as I learned a lot from that time and am glad to report we were finally exonerated but still got shafted from insurance firm as they knew I didn't have the resources to chase them through the courts for my losses.

That's the main reason I feel BMB has made a good point and I for one decided to embrace it and invest in all sorts of daft stuff I know we don't need. As BMB has mentioned there is a far greater awareness of regulations but when I am asked to prove if the 9' span over a garden shed on a 3 lift independent I do shake my head but I also no they are technically entitled to ask and expect an answer, hence the dilemma draw it or pay for it. I would love to scribble a couple of calcs on the back of a fag packet but we all know that aint happening.:embarrest:
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Morning AOM
If you are doing lots of the same sort of work, short spans, bridges over lean too's high first lifts to shops etc. I would feel there is nothing to stop you getting your designs for the first one and creating a generic (worst case) design pack.
In other words Keep the designs you have had prepared create your own folder. A design for a 12m span over a conservatory may well be adequate for a 10m conservatory provided the same design principals are followed.
Take my word for it there are not many propper scaffold engineers out there who want to be drawing this stuff for a living.
regards
Alan
 
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BMB i fully understand the need to have certain jobs designed and them jobs are above the scope of the average scaffolder , the problem is HSE and site managers dont know what is basic and what needs designing , so they look for designs for everything makes you feel like a chimp that is just there to be shown what nuts to tighten up, i like most lads love my job , i love the challenge of getting around awkward corners , or hard to get to places.
Using my brain to think what materials i can use , can i transfer weight from the scaffold to floors or window sills , can i hang something down to support a corner , thats what we do as scaffolders on a daily basis .
I do also understand that a little knowledge can be a dangerous thing and you cant just let anyone loose on certain jobs but surely an experienced scaffolder is capable of more then just tightening up nuts and doing " basic" jobs , if not then we dont need to be trained any futher then this is a double put it in to the drawing instead of all the money time and effort we have all had to go through ?
 
In many cases a scaffolder will be able to trust his intuition and erect a job that is more than capable to withstanding the design loading requirement, but the flipside of this coin is that the structure is often over-engineered (ie "beef it up" and put in loads of extra tube that really isn't required (and sometimes isn't doing anything at all). One of the aims of a design engineer is to maximise strength while minimising material requirement / manual handling / man-hours / risk to personnel etc. We try to take the components to their SW limit, which is something that is near impossible to do without calculation.

In my experience I have also seen plenty as-built jobs that I've had to condemn and issue a drawing for as they would no way stack up to requirements, and I'm sure we've all seen bent tubes / beams or even popped welds where they have been overloaded. Intuition is a powerful thing but some things are hard to judge (reaction loads from cantilever projections / raker loads / overturning / far-side suction etc) for someone without engineering experience.
 
Got to be honest Mark, I have yet to come across a design that minimise's component parts more the opposite in fact. There in lies the gulf between scaffolders and engineer's we know what will hold but as you say impossible to prove without calculation. I must admit it's an interesting thread and does explain a lot.
 
aom said:
Got to be honest Mark, I have yet to come across a design that minimise's component parts more the opposite in fact. There in lies the gulf between scaffolders and engineer's we know what will hold but as you say impossible to prove without calculation. I must admit it's an interesting thread and does explain a lot.
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Well maybe I'm just talking for myself then! There is a minimum of 1.65:1 F.O.S. inherent in the manufacturer's SWL data, design formulae etc so I always try to maximise the usage of materials safe in the knowledge that a little overloading will be tolerated. I think it's great when I can go through a set of calculations and be extremely close to the maximum allowable values all the way through. My experience in engineering is that this is the methodology of most designers where costs are key, but maybe scaffold design engineers are erring on the side of caution too much to make sure their names aren't associated with a failure. After all they get paid the same whether their design takes a week to erect or 2 weeks, but the job with twice as much kit in will inevitably withstand greater loadings. I have a close relationship with the guys who have to erect my drawings so I am always keen to make it easier to read, erect and ultimately making life as easy for them as possible. It is a case of taking care to analyse the design requirements of the job and creating the structure that can fulfill those requirements most effectively.
 
i have known more then one designer to get himself out of trouble with a design by just putting in loads of more gear , i have yet to see a design where there is just the minimum amount of gear involved like Aom says its always the opposite. If scaffolders jobs done from experience are so close to failing then surely we would see a lot more jobs collapsing ?
What needs to happen is that the idiots need to be driven out of our game and contractors need to start employing REAL scaffolders instead of the cheapest cowboy quotes who undercut us and just throw something up, grab the money and run.
There are a lot of scaffolds without sign boards around , why i ask my self would you not want to advertise your company services and show prospective customers what you can do , if your legitimate you would
 
Morning Mark,
I feel you are correct in your assumptions about how scaffolds are in fact engineered with a commercial mind. Having been in this industry for a while now I am also sure that Scaffolders will seldom appreciate the input of a good Engineer.
I would also restate for this post that there are good and bad Engineers in scaffolding as are there good and bad Scaffolders. Good Scaffolders are born out of time in and experience more so than turning up and throwing up volume. Bad Scaffolders tend to be the result of over confidence without basis. Good Engineers are born out of training and time. Bad Engineers are also born out of over confidence and lack of training.
For the uninitiated, the design of scaffolding used to be all long hand, every drawing was produced using a pencil or pen, every alteration was carried out using a razor blade and rubber. All calculations were long hand and hand written. There were no short cuts or computers to stretch the limits with. All the results were taken as gospel, very few were revisited to improve the outcome. Since the introduction of computers to design this has changed dramatically. With the introduction of frame analysis for day to day design has come the ability to alter and move components in a frame to achieve a better result in seconds. This however is where the problems arise.
When an Engineer creates a frame design he inputs the information to attain the best possible result for the frame achieving the best stress configuration allowed in as many components as possible. This frame assumes that all the components are connected in the best possible manner i.e. that the node points (intersections of members) all come together at a certain point in space. This takes no account of the Scaffolder not putting the transoms next to the standards or on singles it takes no account of the brace being a foot from the standard and it takes no account of the Scaffolder stretching a lift. All of which alter the structural capacity of the scaffold.
Having had the misfortune of defending a couple of the world’s largest scaffolding contractors following collapses and failures, my experience tells me it is seldom that the omission of a single component causes a failure, it is more likely to be an accumulation of errors or alterations being built into a scaffold accompanied by the odd removal of ties by a third party. What I can confirm that I have never seen or heard of a failure caused by the insertion of too much kit by either a Scaffolder or an Engineer.
As a point for consideration I pose a question:
If you cannot prove by calculation that something works how do you know that there is enough or not enough kit in it?
Before you answer consider the following:
A scaffold that has not yet failed will seldom tell you how close to failure it is.
If a scaffold is not loaded to the designed loading is it over designed?
A scaffold may not have failed but how do you know what would have happened had it of been loaded to its believed capacity?

Other than gut instinct, what is your qualification for assuming there is too much kit in a designed job? It is worth bearing in mind that all the scaffolds you and our colleagues have or will build in the past or future, have at some time already passed through the hands of the Engineers you choose to insult.
There is nothing new in scaffolding without it being engineered, someone will have done it before you all you can do is try and do it better.
Regards
Alan

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Never meant to insult anybody Alan and if it came across that way I am sorry. I was enjoying chatting to engineer's and getting their perspective on it whilst as usual imparting mine.

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Mark, great you have a close relationship with the erector's which is as it should be. I wasn't questioning if you were right or wrong just commenting that it isn't recognisable from the drawings I have come across. More power to you.
 
Not a problem for me AOM I have broad sholders and have been around a few blocks.
Just trying to stimulate the discussion with a few thoughts from a different perspective.
Keep the thoughts coming, opinions are what makes it interesting
regards
Alan
 
I can’t see where aom was insulting anyone?

it’s that type of high and mighty attitude where engineers think they are better than scaffs that cause most of the problems between engineers and us!
 
everhigher said:
I can’t see where aom was insulting anyone?

it’s that type of high and mighty attitude where engineers think they are better than scaffs that cause most of the problems between engineers and us!
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Your assumption is that my post was directed at AOM. It was not. However stating that Engineers put more in than is required as ageneral statement is an insult to Engineers.

Nothing High and mighty about the attitude at all but you are of course entitled to your opinion, it would appear to be only Engineers that are not entitled.

For the record I have done almost every job within the scaffolding industry over the last 37 years so feel somewhat at liberty to comment.

regards
Alan
 
Hi Alan, your 37 years at the game more than qualifies you to comment and yes I do respect your opinion, however I did get the feeling that everhigher's assumption that insults were being leveled against designers and engineer's to be correct. Rightly or wrongly that's why I never answered your last post, insulting engineer's or anyone else is not my style unless we are toe to toe and there is money at stake. Apologies again if my remark insulted your trade, I was actually enjoying getting some feedback from the men in the know.

I also felt the original poster started a really good thread answering a few common questions and I may have hijacked it slightly to pick hid brain.
 
Alan Reade said:
Your assumption is that my post was directed at AOM. It was not. However stating that Engineers put more in than is required as ageneral statement is an insult to Engineers.

Nothing High and mighty about the attitude at all but you are of course entitled to your opinion, it would appear to be only Engineers that are not entitled.

For the record I have done almost every job within the scaffolding industry over the last 37 years so feel somewhat at liberty to comment.

regards
Alan
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it was directed at someone?

When you have completed your design on a job and done the calculations and they fall just within the acceptable limits, don’t add a bit to push it further over the line.
I to have done a few jobs in my time (only 26 years) and you would be the first engineer that I know of that wouldn’t add a bit. All the ones I have worked with do. It’s called ass covering and the result is we have to erect these over designed jobs. Which are normally priced by someone thinking as a scaff and don’t have the money in to cover making the engineer feel comfortable
Crossing the M25 with your eyes closed will get you killed, but we erect scaffolds with our eyes open wide.
Most anyone can make a job stand up, it’s about just making it stand up within the code
 
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