Need 3d symbol of Steel Bar Joists

[raltd9245]

I'm doing a residence with a steel bar joist roof found 2D symbols but would like a 3D cad symbol. any Ideas.

Ron Ravenscroft

[mtldesigns]

14 minutes ago, raltd9245 said:

with a steel bar joist roof found 2D symbols but would like a 3D cad symbol. any Ideas

Small world, I just got a project of the same caliper and thinking the same thing.  But also ideas on steel joist/corrugated base with concrete slab second floor.  Not the Out Of The Box stuff in Chief.  

[raltd9245]

3 minutes ago, mtldesigns said:

Small world, I just got a project of the same caliper and thinking the same thing.  But also ideas on steel joist/corrugated base with concrete slab second floor.  Not the Out Of The Box stuff in Chief.  

I have downloaded 2d symbols but no 3D.

[robdyck]

Depending on the level of accuracy that you'd like to model, you can use a floor truss to replicate the webs (adjust component sizes and material) and you can use a joist to act as the top chord. This will provide a simplified level of modelling. If you need more accurate modelling, then of course 3d symbols will need to be imported or created.

 

Awhile back I created my own in 4' incremental lengths. My method:

1. Create a symbol for the top & bottom chord with a suitable stretch plane. 
2. use a 3d molding to create the webs.
3. marquee select and convert to a symbol with stretch planes near the ends to maintain the clip lengths.
4. Joist the floor using the closest length joist and stretch or shrink as needed. Not perfect, but looks very close.

[mtldesigns]

34 minutes ago, robdyck said:

floor truss to replicate the webs (adjust component sizes and material) and you can use a joist to act as the top chord.

Ok, this is def. doable. I can then build the flooring sub structure based on this (corrugated and concrete).  I will have 2D details, so total "visual" accuracy in the model itself for the most part isn't really needed.  The dimensions will be correct, just don't need to make a 3D solid of the corrugated throughout, if that makes sense.  

[robdyck]

13 hours ago, mtldesigns said:

just don't need to make a 3D solid of the corrugated throughout, if that makes sense.

Exactly. 3d of the corr. metal and concrete becomes a real hassle, especially if your design is prone to changes. That being said, keep in mind that when a 3d model is very accurate, then most of the work is already done for section details. In the plan from where I grabbed those screenshots, I did have it all modeled in 3d which helped me with the 2d details, simply because there were quite a few and I used all live section cameras for my sections and section details.

 

So in summary, it's helpful to try to think ahead about the level of accuracy that you need relative to the number of drawings that will make it into your plan view. 

And of course another factor to bring into this equation is the re-use of details / components. A tidy 2d CAD detail is very easy to re-use, where as items based on the 3d model are not quite as quick and simple to re-use (or add to a template plan).

[Kbird1]

Try a little Forum searching perhaps, as I seem to remember Michael (Alaskan_Son) doing a library or symbol or something for these a couple of years ago maybe?

 

 

M.