Steel Shop Drawings

[joemarch]

I think I need to vent a little bit......

Once and awhile I will get a request for the structural drawings and details from the structural steel supplier. I've always had a bad vibe about the steel supplier using the drawings as erection drawings. I clearly state on my drawings (in my structural notes) that the fabricator shall provide his/her own erection drawings.

My take on the whole deal:

1. If my drawings are being used as erection drawings then I should be getter payed for them.

2. Providing "fresh" drawings from the fabricator provides a second check.

3. The whole bidding thing (one guy bids the job assuming he provides drawings and the other under bids the job thinking he won't have to provide the drawings).

I recently rejected giving the electronic files to the steel fabricator, which then sent the contractor into a 5 year old temper tantrum. I tried to explain to him the things stated above. He gives me this,"the owner owns the drawings". I tried to explain that I still hold the liability for those drawings. Then he went on to say that this steel fabricator saved the owner like 200k and blah, blah, blah...

I just have a bitter taste in my mouth about this subject. Let me know what you guys/gals have dealt with this. Thanks

 

[71corvette]

Unless it's commonplace to give fabricators electonic drawings in your area of the industry (it is not in mine), the fabricator should be bidding the job assuming that they will need to create shops from scratch. I've been approached on this in the past and I really can't blame them for trying, the fabricator can make a fair amount of extra profit by eliminating this portion of the work. As for the contractor, sounds like typical intimidation tactics. I've met more than one of those guys in my day.

As for the drawings belonging to the owner, unless your client requires electronic submissions, I believe they only own the stamped hard copies (I wouldn't want to be the one to tell the client this though...)

On a side note, if an owner does require electronic drawings (actual cadd files), is there typically a clause in the contract which prevents the owner from disseminating those drawings to others (especially competitors).

 

[VirtualEngineer]

I guess I won’t get an “atta boy” with this post but I'm sorry, I kind of agree with the fabricator.

I've been working out here in the eastern part of the US and going back at least 50 years (I've personally experienced 25 or so), usually the fabricators make copies of the design drawings and put their piece marks on them. This is fairly common practice. Check some of the old AISC detailing manuals. They may even make reference to this procedure.

In the old days, they would make sepias and eradicate out information and details they didn't need, and then add whatever erection details may be called for.

I actually prefer them to use copies of my design drawings; otherwise I have to do a complete copy check of whatever erection drawing they create to verify it complies with my original design.

I am sure that the fabricator can just use a scanned copy of your design drawing to create his erection drawing, but a cadd file is more convenient.

Another thing to consider is the fact that having a good relationship with the fabricator is a valuable asset. He can be a big help in spotting any minor discrepancies. While preparing the details, he goes over the fit up details with a fine tooth comb. You don't want to lose his cooperation in bringing problems to your attention.

Regards,

JPJ

 

[JedClampett]

This issue might get hotter in the future. With the direction that computers are going, I can see a time where the Autocad or whatever files are given to the detailer and the piece marks, beam lengths and connections are automatically spit out. Heck, maybe there's some software already available that does this. Of course, the process will never be completely automated, but there's a lot of information that the design engineer produces that the detailers have to replicate. And maybe we'll have to adjust our drawings a little to make the software understand them better.
I think that structural engineers (all engineers)should be receptive to anything that makes a project cheaper and more accurate.

 

[cyrusr]

I'm a young mechanical engineer, studying to become a structural engineer. While I think that large amounts of data can be processed with computers, I also feel that they are becoming more and more of a crutch and less of a tool. Many people can generate a pretty picture, but when it comes down to it, grabage in, garbage out.

JedClampett - A fabricator that we used on a job had Xsteel, which took the one line drawings and generated the fabrication and erection drawings automatically including the connections.

-Cyrus

 

[JedClampett]

So, Cyrus, you got me in suspense. How did it work?

 

[TFL]

IN THOERY I HAVE NO PROBLEM WITH A FABRICATOR TAKING AN AUTOCAD OR RAM MODEL AND USING IS TO PRODUCE SHOPE DRAWINGS. HOWEVER THEORY IS NOT REALITY.

IN REALITY HOW OFTEN DO WE HAVE EVERY MEMBER LOCATED TO THE 1/16TH OF AN INCH. OUR LEVEL OF ACCURACY JUST DOES NOT MEET THEIR NEEDS

 

[steve1]

I am curently finshing up a degree program in computer aided drafting (degree #5). I can tell you where the future is heading - one 3D model of the entire building that will be used by all disiplines. In the process a new entity will be added to the design team, the building modeler. The modler will be responsible for integrating the various data into one model.

This 3D model will contain all architectural, structural, mechanical, and electrical info. Each disipline will add their database to the model, in addition to using it for analysis and design purposes. The model will then be sent to the various fabricators and suppliers who will produce their shop drawings from it.

As built info will be added during the process. All construction sites will have electronic access to the model and will print out drawings as required.

There is alot more to autocad type programs than simply drawing lines on paper.

 

[craigory28]

My two cents...

There is a lot of good points made in this discussion. There was an article in Structural Engineer just recently describing what Steve is talking about.

We allow structural details to use our drawings only after they sign a waiver saying that we are not responsible for the content of the drawings. To often we manually change a dimension if it is 1/4" off instead of redrawing everything. This could make a huge difference when detailing a drawing. If it is another discipline i.e. fire protection. We tend to charge them for our drawings. With sharing drawings I have developed good working relationships with engineers and like Virtual Engineer states it can be very beneficial.

On a side note if I share my drawings with a company and they do not remove my company's logo or something similar, I reject the shop drawings without looking at them and send them back. In my opinion, it isn't my drawing and they are being really lazy.

 

[SperlingPE]

I have allowed suppliers to use the contract drawings for their shop drawings, when they have asked and when they understand that it does not relieve them from checking dimensions and all other functins that they normally do. I will include some legal waiver (that is about worth the ink that it is printed with) on the drawing. Basically they can use it as their erection plan drawing showing sizes and piece marks and that is about it. Dimensions and detail marks must be added by the supplier. References to my company and my stamp must be removed.

 

[RARWOOD]

As an engineer working for a fabricator, I think it is a bad idea and not in the best intrest of the owner, to allow the fabricator to use cad files from the architect or engineer for their shop drawings.

I feel this way mainly because the company I work for can not afford the costs that may arise if the orginally drawings are inaccurate. The main reason we draw our own erection plans is to verify the accuracy of the information we have been given to work with.

It would be great if we could use the architects cad files and back charge the architect to replace any beams which were made too short because of a dimensional error in the cad files. The possibility of back charges, is why I don't think it is in the owners best intrest for the fabricators to use the architects cad files.

Even in a case where the fabricator ends up absorbing the loss, it is likely to add project costs somewhere else. It seems future back charges get inflated when a contractor or vendor absorbs a prior loss in a project.

I also think today there is to much dependence on Cad. I have dealt with too many people who when asked for dimensional information will just pull it off cad and give no though as to whether or not the information makes any sense.

The company I work for has a hard enough time assuring that our own people are drawing accurately, that we don't need the headache of basing our fabrications on someone else drawings which may have errors.