Argument in Dimensioning

[ReMark]

I keep a minimum 1/16th of an inch off the object for the start of my extension lines. Once in awhile I'll bump this up to 3/32nds. This of course can be preset in your Dimstyle as you well know.

[Ryder76]

How would I adjust these lines I have circled then? The only ways I know how would be to manually adjust by grabbing the node and pulling back (which could lead to inaccuracies in the dims) or setting the offset in the properties pallet for each dim line.

 

I pride myself on making quick and accurate drawings and to do either one of these options means spending a few seconds more on each and every dim line that "doesn't look right".

 

Also if your dim is too far away from the object then you're going to have guess work for the reader.

 

I hope this topic isn't getting bothersome I'm just trying to understand.

 

No problem - When you grab the node snap it to the diagram line the offset in your dimstyle should be enough - if not change that in your properties or make a new dimstyle.

 

The 1/8" dim is fine. It is ok to have some dim lines on your part when it is the only way to accurately show the dimension, otherwise the dimlines should not cross the part or any other dimlines or leaders. With dimensioning there are rules to follow and exceptions to those rules.

 

And here is some more advice - sometimes it is better to just do it the way your supvervisor tells you even if they are ignorant of the truth.

[dbroada]

I keep a minimum 1/16th of an inch off the object for the start of my extension lines. Once in awhile I'll bump this up to 3/32nds. This of course can be preset in your Dimstyle as you well know.

just an observation here (not aimed at Mark) but it has been stated that there must be a gap between the object and the dimension lines. That was how I was taught as covered in British Standard BS308. However the latest edition of that publication (now with a long EEC number) calls for NO gap. Now that I'm used to it I do prefer it that way and find it easier to read. However my point is while all observations are relevant you should not tell people on this forum that things MUST be done this way. Local standards could easilly be broken that way.

 

This also emphasises why it is a good idea to include in yoour profile your country of residence.

[ReMark]

Without the gap things could get a bit confusing. I assume that you (Dave) use lineweight as a key indicator of what is geometry and what is a dimension. Yes?

[dbroada]

actually we don't, we use the ctb file. Cyan is our 1 thick colour, all other colours being thin. After a while you just get used to seeing cyan lines as thick. Of course our engineers insist on printing from true view and are far too busy to read the instructions I typed about using a ctb file so their drawings ARE confusing

[Ryder76]

Hey Dave & Mark,

 

I agree about including the country. Our standards here across the pond are not always the same. And I also agree about the MUST thing. Even as invloved as the dimesion standards are here in the US there are exceptions to rules. Basically, when it all gets boiled down - follow the rule in all cases accept when it is impossible and then follow the exceptions or if you can't then ensure the drawing in question is dimensioned to the point that it is clear and can't be misconstrued.

 

Like you Mark, I usually use a 1/16" offset from the item being dimensioned.

 

Dimensioning and drawing to scale is a pet peeve of mine. I'm sure yal have been exposed to the horrors of poor dimensioning practices and could probably co-write a book with me.

 

Anyway, I hope the OP gained insight and with all the wonderful information about what books to learn from I'm sure he/she will be a "world class dimensioning fool" ...in time.

 

BTW Dave good to have you back.

[dbroada]

BTW Dave good to have you back.

thanks but I haven't yet been! Pressure of work is keeping me away from the keyboard ATM. This time tomorrow night I will either be on the ferry going to France or more hopefully be already there having got away from work promptly and caught an earlier ferry.

[Ryder76]

Well...hopefully you will get to leave when you want and have a great time! I'll drink a beer to you and your family's honor.

[bbankston]

Thanks for the help, folks. I'll let you know how it pans out if you're interested.

 

Brandon Bankston

[rkent]

There isn't much you can do sometimes to avoid crossing the object, and as was pointed out above, don't have dim lines starting on the object.

 

I would have a bigger complaint with leader arrows pointing to open space, you have two of those.

[ReMark]

Maybe a "detail" of the congested area would have helped. Some of the dimensions could have appeared with the detail. Keep in mind dimensions should normally not be repeated.

[JD Mather]

I am not going to go through the entire set of rules, but we should carefully define out terms. There is some confusion here between dimension lines and extension lines.

There should be a 1/16" gap between extension line endpoint and the edge it is dimensioning. It is permissible for an extension line to cross over an object line that it is not dimensioning to. I think there is an example of this in lower rightish area of your drawing.

For actual dimension lines you can use wipeouts or other techniques to create gap over object lines or other dimension lines where not avoidable. Modern programs like Autodesk Inventor do this automatically for you.

In short, the standards can be set up in your dimstyles and should not require any extra work for the most part. The biggest problem I see is with dimensioning to points rather than to edges resulting in no gap between object line edge and extension line. As noted there are serveral books covering national standards as well as company defined standard references.

The entire goal is to make an aesthetically pleasing drawing that is easy to read and less likely to be misread resulting in costly mistakes. Extra work, if required, on the part of the drafter can save significant money out in the shop/field with reduced errors.