Development and Updates for the Medeek Truss Plugin

[Medeek]

This is an example of the wireframe (temporary) graphic that is shown while creating a valley set.

[Medeek]

I've repackaged the .rbz file this morning so that when it installs into SU 2017 the extension will have the appropriate hash file and appear as "signed".  I have not yet rolled the revision (1.7.0) which includes the updates for stepdown hip truss sets, there is still substantial work before I am ready to release that module and version.

[Medeek]

Version 1.7.0 - 12.04.2016
- Added a "Layers" tab within the global settings; roof, wall and floor components can be assigned to specific layers.
- Enabled custom layers for the common fink truss.

Note that I have only enabled custom layers for one type of common truss (fink).  To enable custom layers for all other truss types, rafter roofs and other misc. items will take a few hours of going through each module of the plugin and adding in the "layers" code or conditional statements.  My arm/neck is not holding up very well but I thought it would be nice to at least get this out there for the most common truss type for testing purposes and feedback.

[Medeek]

I've had a number of people asking about adding in the connector plates for the trusses.  After giving this some thought it doesn't seem like too much work to implement.  I will try and work on this today and this evening.

I've already added in the option into the global settings:



Plate thickness can be set by the user (inches or mm).  The default will be 0.0575 inches (1.46 mm) which is the total thickness of a typical Mitek M-16 connector plate:

http://www.icc-es.org/reports/pdf_files/ESR-1311.pdf

If I could find some additional help for programming that would be useful right now.  I've come to the realization that I cannot realistically program all of the stuff I have planned.  I really need to expand this beyond a one man show.

[Medeek]

Version 1.7.1 - 12.08.2016
- Added truss connector plates within the global settings, plate thickness can be specified.
- Added a "roof_mpc" layer for roof truss plates, connector plates can be assigned to a specific layer.
- Enabled metal plate connectors for the common fink truss.



As with the recent layer upgrade I have only enabled connector plates for the common fink truss.  This is to provide a test bed for the connectors then once the interface is fined tuned I will roll it out for all truss types.

At the moment the plate sizes are hard coded in.  I am still trying to decide on the best method to use so that the connector plates can all be sized by the user.  The objective is to make this a flexible as possible while at the same time not over complicating things.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=8e1d46c3-e1e2-4bc9-b16b-69aa1085c8d1

[Medeek]

What I think I will do is add in one more option in the global settings which allows one to toggle the plate sizing to either auto or manual.

If auto is selected I will create a basic algorithm that looks at the truss span, truss pitch and depth of the TC, BC and webs and then sizes the plates accordingly.  I already have such an algorithm built into my Truss Designer here:

http://design.medeek.com/calculator/calculator.pl

If manual is selected I will have an additional html input screen appear that shows the location and size of each plate as well as the outline of the truss.  The input will look similar to this:



As each plate is adjusted it will immediately change in size showing exactly the configuration of the truss with its connector plates.  This involve quite a bit more coding however once I create one such html input, creating more will not be such a big deal.  Each plate will be labeled P1, P2, P3 etc...  Typically the location and rotation of each plate will have an optimal setting that does not need user input or adjustment.

The only question now is how to handle the gable end trusses.  I think for now I will auto-size the plates on them using the same heel and peak plate sizes as the common trusses.  For the the vertical studs I can use an algorithm that looks at stud length and then chooses either a 1.5x3 or 2x4 plate for connection to the top and bottom chords.

Adding connector plates adds a whole new level of complexity, but there have been enough requests for it that I think it is a valid endeavor.  After all this is the "Truss Plugin" and I might as well get the trusses right.

[Medeek]

Enabled connector plates for the common gable truss:



There gets to be quite a bit of geometry when you start modeling all of the plates, especially the gable trusses with all of their vertical studs.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=0f1b6741-f503-43e9-a627-663ceabec33b

[Medeek]

As an interesting side note, one can turn off the truss layer and then measure the volume of the steel plates which yields 113.85 in³.  Multiply this by 0.284 for mild steel and you end up with a total weight of 32.3 lbs.  That is actually quite a bit of steel plates in this rather small truss package.  No wonder the truss plate manufacturers like Mitek make so much money on the sale of truss plates, the volume of steel is definitely there (194 plates).

The weight of the wood can just as easily be computed, making an assumption on the wood species (G, specific gravity of the wood), and moisture content (typically 19% at dry service conditions).

The appropriate equation to use for the density of wood can be found in the AWC NDS:

http://design.medeek.com/resources/documents/NDS2012_SUPPLEMENT_P12.pdf

For DF No. 2 the density would be 34.2 lbs/ft³

The volume of the wood is 22.06 ft³, multipled by 34.2 lbs/ft³ yields a total weight of the wood at 754.5 lbs.  Steel plus Wood = 786.8 lbs.

It may be useful to provide weight information at both the truss component level and the entire truss assembly, wood, steel and total weight.

[Medeek]

Enabled metal plate connectors for the 4/4 and 6/4 scissor trusses:



Each truss type and configuration needs its own special function to locate and auto-size each plate.  The code required is not difficult since most of it can be recycled but it is still time consuming to generate for each and every truss type with all of the many possible configurations.  I have not even considered raised heel trusses yet.  At some locations (ie. heel plates on a scissor truss) the truss configuration may cause the plate to fall outside of the perimeter of the truss in this case some additional logic is required to check for these instances.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=16954124-d987-4a72-be11-5089a6be6221

[Medeek]

When it comes to plates and connectors there is also the bolted plate connected trusses with larger timber members used for more architectural and ornamental work.  I am wondering if there is any interest in having a separate module for those truss types?

Something along these lines:

[Medeek]

The current TODO list:

1.  Hip Sets (Stepdown, California, Midwest, Northeast, Terminal) with and without drop-in purlin frames as applicable. Hip truss algorithm per June 15, 2016 post.
2.  Flat Trusses with html input.
3.  Barrel Vault, Clerestory, Studio Vault, and Double Inverted trusses.
4.  Html menus for each truss type.
5.  Update the manual and create more video tutorials.
6.  Extend connector plates and layers to each truss and roof type.
7.  Open Joist Floor Trusses.
8.  Polygon entry for floor trusses/joists versus currently available rectangular assemblies, also add in a function to cut a hole in the floor for a stair way or other opening. See Jul. 2, 2016 post.
9.  Dutch and Half Hip truss sets (See Jun. 14, 2016 post).
10.  Gable roof with solid sawn beam.
11.  Gable roof with "two" glulam or solid sawn beams. (cantilevered rafters).
12.  Html menu for each truss type for manual connector plate sizing.
13.  Add the roof to the gable dormer, see June 19, 2016 post.
14.  Hip and Shed Dormer.
15.  Gable, Hip and Dutch Gable Roof Minor.
16.  Engineering for Rafters, Joists and Sheathing.
17.  Bring the truss and beam engineering into the plugin versus an external link to my engineering site.  This would require porting all of my Perl code into Ruby.
18.  Add a dual pitch gable rafter roof.
19.  Add raised heels to each truss type that currently does not have this feature.
20.  Finish adding bird blocking option.
21.  PDF or HTML output (printable) showing details of a truss assembly (ie. shop drawings and layout)
22.  Update order system allowing $20 yearly license renewal.
23.  Further investigate materials (colors) for specific layers.
24.  Allow "editing" of a truss, floor or roof assembly.
25.  Timber trusses (with bolted plates).
26.  Complex hip roofs, this is related to roof minors (item 15).  Need to devise a straight skeleton algorithm.
27.  Integrate more tightly with other plugins as opportunity arises (ie. Estimator etc...)
28.  Gable end trusses for gambrel attic and attic trusses.
29.  Complete all configurations of each truss type and verify that each advanced option is correctly working (ie. polynesian truss needs more configurations).
30.  Add gable and full returns to the roof return option, currently only the hip return is available.
31.  Transition trusses.
32.  The Trim function seems to be working now I need to work on the Extend function.
33.  Steel and hybrid steel floor trusses.
34.  Explore adding in a stairway module and deck module, however these may become part of the upcoming Wall Plugin.
35.  In the advanced options for gambrel attic trusses create an option for a crow's beak, see June 20, 2016 post.

I know I'm missing a few items that I have on one of my paper lists but I can't find it right now.

The question is, other than item 1, what are the highest priority items on this list?

I've been basically sidelined since end of August so I am anxious to get this operation (neck) done with and over and really begin again in earnest to advance the development of the plugin.

My new job keeps me busy but not so busy that I can't spend a few hours each night plugging away at this list and weekends are certainly my friend in that regard.

Please feel free to let me know what other items should be added to the list.

[Medeek]

I need to review some of my old files (local residential designs) to get a better idea of timber truss designs but out of curiosity I attempted to manually create a sample timber truss to see how long it took me create one.  About an hour into it I had come up with this:



View model here:

https://3dwarehouse.sketchup.com/model.html?id=355ab1aa-b040-4fca-a5c2-393f49bf71d8


Specifications:

- King Post truss with 4:12 pitch, 12" overhang and 1/4" buttcut, span 28'
- 6x10 Timbers (TC, BC, King Post)
- 3/8" Thick Connector Plates
- 5/8" DIA. Heavy Hex Nuts and Bolts
- 2 Rows of Bolts
- 4.5" between rows of bolts
- 4" bolt spacing between bolts in a row
- Plates offset from timber by 3/4"
- Bolts offset from end of plates by 2"
- Bolts offset from edge of plates by 1.5"
- No washers

This particular connector plate configuration uses two additional bolts at the apex of the heel plates, many other variations are possible.

Please feel free to comment.  This example is just a concept to give me a better idea of the design parameters and issues with this type of truss.

[Medeek]

Version 1.7.2 - 12.16.2016
- Enabled custom layers for roof returns, battens and counter battens.
- License renewal enabled in Medeek Account Manager.

[Medeek]

I like the new addition of the layers, it helps being able to hide certain aspects of the model.  This has led me to think it might be useful to somehow implement materials (colors, textures), either at the layer level or based on the geometry (ie. specific color or texture for the I-joist web -> OSB wood).

[Medeek]

Version 1.7.3 - 12.17.2016
- Added a "Materials" tab within the global settings; Auto material assigment (colors and textures) is now an option.
- Enabled materials and custom layers for floor trusses and joists.
- Enabled materials for common trusses: metal plate connectors, lumber, and OSB.



View model here:

https://3dwarehouse.sketchup.com/model.html?id=d9b8fa16-5a7a-43f8-8da5-fc8b913bcba7



A big thanks to those on the SketchUcation and SU board who helped me with the custom materials part of the API, the SketchUp community is a great asset.

By default the metal plate connectors, custom layers and auto materials is turned off in the global settings.