INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Query on Plant Layout drawings

Query on Plant Layout drawings

(OP)
Hi folks,
I have a small query on creating Plant layout drawings in AutoCAD. I just wanted to know how to start and proceed big drawings( in metres) such as Plant Layouts.My doubt is on setting the drawing limits, Plot scale (for plotting the drawing on an A3 sheet),if the drawing is given with a scale of 1:30 ,should I use the scale command.how do I manage the annotations and dimensions sizes for such drawings in print?

Can you please detail me on proceeding for such a drawing from scratch to Print?

Thanks in Advance.

RE: Query on Plant Layout drawings

Drawing extents/limits isn't something I worry about too much... I normally include property boundary. I use a standard set of drawing layers... similar to the AIA, but, with a heavier emphasis on structural items. If you have a survey, then you can include it on a layer. I make sure that the surveyor provides AutoCAD compatible drawings of his survey with the data on it. I may have 2 or 3 survey layers, all with different text heights for different scales. This solves the problem of having different text heights for the survey information if used for different drawing scales. . I then establish a base point on plan. This can be an actual benchmark, a property stake, a building corner, or whatever (something that will not move), and establish all work locations relative to this. I will define a new building corners as an x, y, and z offset from this 'benchmark'. I then go ahead and start my new structure with a building outline on the plan and the actual building drawings off the plan area. I use paperspace to set things out for plotting. Real CAD people may do differently; I've never taken any formal CAD courses... strictly from Omura's Mastering AutoCAD from several decades back.

I don't know if there is a current edition, but, the book was fabulous and an incredible help.

Dik

RE: Query on Plant Layout drawings

(OP)
Hi Dik,
Thanks a lot for your details.Highly appreciate your response.
But I just wanted to know how to start and proceed on a A0 size drawing in AUTOCAD?
What are the steps involved in it as it is a bigger size?

RE: Query on Plant Layout drawings

No difference... just use a bigger/smaller scale to suit... I have standard defpoint drawing sizes with 1/2" border... I put them on the model and increase them by the scale factor ... pretty quickly zero's in on the maximum scale you can use. A real CAD operator may have a better method than mine...

Dik

RE: Query on Plant Layout drawings

Was just thinking (an occasional occurrence) if you can use an A1 rather than an A0, you can shrink the drawing to an 11x17 size... I find the text on A0 to be too small when shrunk. it's a lot easier to work with in the field.

No one likes to work with large sheets.

Dik

RE: Query on Plant Layout drawings

(OP)
Thanks a lot Dk. Hope I can try these tips.

RE: Query on Plant Layout drawings

Glad to help... I was hoping that some one more knowledge would 'jump in'... there may be more professional ways of dealing with this.

Dik

RE: Query on Plant Layout drawings

I learned AutoCAD by reading 'Inside AutoCAD' from front to back, and working _all_ of the examples.
That was when version 10 (for DOS) was current.
I have no idea what text might be most useful now, but I do suggest working through one such guide instead of wandering aimlessly.
At least search YouTube for answers to your questions.


General suggestions:
Don't worry about drawing limits.
Aside from a numeric range limited to something like 16 decimal digits, the universe within AutoCAD has no serious limits. ... or units, really.
You can draw in Angstroms or in light years, it makes no real difference.
But you must draw full size, i.e., 1 unit on the model screen is one of whatever unit you choose.
Using the UNITS command or dialog early can be helpful with strange units like feet and inches.
Draw in Model Space only.
Dimension and annotate in Paper Space, mostly.

It helps to have a prototype drawing file to start from, hopefully something that's in the units you want, with a useful layer arrangement, and of an object about the overall size of what you want. Copy the file, or open and save under a different name, erase everything you don't need, and go. You can eventually make your own, but it's easier to start with one from someone who knows the software. There is a risk if you get a prototype from someone who is self-taught and does everything 'wrong' but in an internally consistent way, you will have difficulty producing what _you_ want.

Mike Halloran
Pembroke Pines, FL, USA

RE: Query on Plant Layout drawings

Thanks Mike... pretty much the same boat... I forced myself to sit down and do a chapter a night until I had completed the book. Maybe the site's policies about only engineers may restrict the comment. I was hoping that a real CAD operator that had been formally trained might be able to offer more technical information.

Quote (Mike)

But you must draw full size
Draw in Model Space only.
Dimension and annotate in Paper Space, mostly.

Missed those... and, drawing full size is critical and an essential habit to get into... A lot of my standard details are annotated with the drawing detail and scale factor of 16 and some with 12, but, often something else... I usually have my standard details in a defpoints 'box' with the dimscale, ltscale, text size, and last revision date outside the 'box'. I 'block' them into the model drawing and use different scale factors for the views in paperspace. There may be a proper way to do it... not aware of it. Just what I've done over the decades.

Should have added that honouring layer types is also critical and inserting blocks on Layer 0 is also important.

I usually have my borders and titleblocks as separate blocks with the titleblocks having attributes and insert these into paperspace; for a large project the common 'attributes' are filled in prior to inserting the block so I don't have to add them to the paperspace drawings. I also name the tabs in paperspace with the actual drawing name, eg., 17304S01, 17304S02, etc.

Dik

RE: Query on Plant Layout drawings

My comments pretty much fall in line with dik and MikeHalloran. However, I am also a self taught AutoCAD Certified Professional (ACP) with no formal training apart from OTJ experience.

We draw all drawings in model space but non-scaled drawings (i.e., P&IDs, PFDs, Isometrics) are dimensioned and annotated in model space and all scaled drawings are dimensioned and annotated (i.e., plot plans, orthos, etc.) in paper space. We plot everything to ANSI D (22x34) which allows us to print a true half scale to ANSI B (11x17) for convenience of handling. The only exception to that is Isometrics which are plotted ANSI B.

All annotation and dimensioning are done in paper space. Text heights are 0.125 (1/8") for general text, notes, and annotations and 0.1875 (3/16") for titles, labeling, and equipment tagging. Dimensions are left in inches up to 2'-0". Any dimension >/= 2'-0" is shown in feet-inch notation.

Every component is assigned a layer when drawn and all layers are given a discipline designator prefix (i.e., C for civil, P for piping, etc.) for ease of locating in the layer manager.

We don't really have a set scale for the drawings as the type of drawing can vary the scale. However, you can view the link below for common engineering scales.

https://www.engineeringtoolbox.com/scaling-bluepri...

Hope this helps,

DGrayPPD

RE: Query on Plant Layout drawings

(OP)
Hi Folks,
Delighted to receive such a detailed replies from you all. Wonderful!!

RE: Query on Plant Layout drawings

Typically use ANSI D, but, text is 5/64... some clients want 1/8". the smaller font is 'readable' when drawings are printed 11x17. I have a HP 350C D size plotter in the basement... my wife got upset and had me move it from the living room and due to difficulty, I hardly ever use it. Usually use ANSI D for drawing size... and plot to *.pdf which I can print on my laser printer...

Seems like everyone was 'self-taught'...

Dik

RE: Query on Plant Layout drawings

Go online for ACAD tutorials. From this forum you can not expect to learn ACAD correctly while it would take students several weeks to learn it correctly. I could teach you all the information that you are requesting but it would take several pages of instruction which is not the intent of this forum.

RE: Query on Plant Layout drawings

The resource provided by DIK is pretty a similar format that I used when I taught ACAD back about 17 years ago. It is a good program although it does lack a few features. Use it.

RE: Query on Plant Layout drawings

We had the same thoughts... tutorials... posted at 15 seconds apart...

Dik

RE: Query on Plant Layout drawings

(OP)
Hi Folks,
In continuation to this,i would like to clarify few points on units. When i start a drawing in metres (1 unit = 1 metres),what are the things I should consider when i take it to a print on an A3 paper which is in mm. Does it cause any problems? Need some light on this.

RE: Query on Plant Layout drawings

It shouldn't... draw your model space in units = m. Set your sheet and title block in paper space as full size in mm. Set your viewports and set the model space scale to suit... it's very easy and fast. Hopefully you've gone through a couple of tutorials on paperspace. There was one tutorial I encountered that was excellent, and, I cannot locate it. Good

Dik

RE: Query on Plant Layout drawings

(OP)
Excellent!Thank you Dik.May be I should try these tips straight away.

RE: Query on Plant Layout drawings

I'm a big supporter of 'tinkering' and I think too few people do it these days... once you have a working drawing in both model and paperspace, it's a matter of changing a few things, moving a few things around, etc. just to become familiar with the cad program.

As a caution, it is possible to change the original model from paperspace, so be careful and 'lock' your viewports.

Dik

RE: Query on Plant Layout drawings

(OP)
Hi folks,
In continuation to this, I just want to clearly understand the concept of defining limits in an AutoCAD drawing.
For example, I can draw any drawing of any size (which is in metres or MM) approximately and proportionally without any specific dimensions and I can take a print on any size. What is the significance of setting the drawing limits for a drawing? How does it affect my drawing sizes and Print sizes? Need more clarity on this topic please.

RE: Query on Plant Layout drawings

I don't use limits at all. I draw full-size, full-scale in model space. I draw in inches, decimals or millimeters depending on how the actual construction is measured. Only parts go in model space, everything else in paper space. I scale viewports in paperspace either for clarity or to specific scales if people will scale off the drawing in the field.

RE: Query on Plant Layout drawings

(OP)
Hi IFRS,
Thanks a lot for your insights.I expect few more replies from our experts on this.

RE: Query on Plant Layout drawings

A note about scales not mentioned yet.
After you've settled on a paper size you are going to use and have your border setup, you then know the biggest viewport you can fit on a sheet. Ideally, you will want to use the biggest viewport you can leaving room for notes, legends, keyplan, etc.

Once you have your basic viewport set, you can set your scale. The scale of your viewport(s) should be the smallest possible to fit your plan within the confines of the viewport AND be a standard scale. If you find that the drawing is illegible when showing the limits of the plant consider breaking things up and show only a portion of the plant on a sheet. This doesn't mean breaking up the model space drawing, just show a portion of the model in each viewport on each sheet. There is no limit to the number of sheets you can use, use as many as is necessary, a few years back I had a project that used about 20 sheets. The important thing is that the plans are legible. (And the same scale from sheet to sheet.)

A "standard" scale being a scale found on your desktop scale and fall into one of two types architectural and engineering. In my work, I use almost exclusively Architectural scales (1/8=1'-0", 1/4"=1'-0", 3/16"=1'-0", etc) so am not that familiar with all the standard engineering scales although 1:30 does look like one.

RE: Query on Plant Layout drawings

Standard scales are only needed if a user will use paper copies of the drawing and wants to measure things on the paper. This assumes of course that I know the printer they are using, their paper size and available print area, and that they are not using a copier or printer that arbitrarily prints to fit or copies not quite 1 to 1. Half of my clients never do this - they are machine or fabrication shops, their drawings are always B size 11 x 17 with viewports scaled for clarity, I zoom in to details without the need to restrict myself to standard scales.

RE: Query on Plant Layout drawings

(OP)
Hi,
Thanks a lot for your insights IFR and Dbill74 .very useful information. What I understand is that the plot scale of 1:1 is not mandatory in all cases and that the drawing just needs to be legible enough.
So can we conclude that the drawing limits we set is used for setting the sheet size on which we would be plotting?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close