Adjust Member Cuts to Improve Plating

Before you begin, select a profile truss, such as a Common truss.

A plate pair can be over capacity because of how the members meet at the joint, not because the plate is too small. When several members are cut to different reference lines, the plate may not have enough of each member to grip. Adjusting the member cuts so they meet cleanly can often fix the plate without requiring a larger plate.

Run a detailed analysis

Step 1 - Click Analysis Options

Analysis Options is the gear button next to Analyze in the top toolbar.

Step 2 - Check Detailed

A detailed analysis provides more information about what is exceeding capacity, helping you determine the right fix. Detailed is unchecked by default; select it to see additional information.

Step 3 - Close the options and click Analyze

Find the failing plate

Step 1 - Click Analysis and History

Analysis and History is the history icon in the top toolbar. It is available once the truss has been analyzed. The panel opens in the left sidebar, with the check results below the analysis history.

Step 2 - In the check results, expand Plates

The Plates row shows the highest plate capacity on the truss, such as "Plates 99%". The plate pairs are listed with their highest capacity first. A plate pair over 100% fails. Note which joint it sits on and which members meet there.

Step 3 - Select the failing plate pair, such as 2 under Plates, or click it in the scene

Plate pairs are named after the joint they sit on, so Plate Pair 2 is the plate at joint 2.

Step 4 - Click Delete Selected Item(s) to delete the plate pair

You can also press Delete. With the plate removed, you can see how the members meet at the joint. Running the analysis again will replate the joint.

Adjust the web's cuts

Step 1 - Select the web that meets the joint, such as W2 under Members, or click it in the scene

Step 2 - Find Bottom Cuts in the member properties

Bottom Cuts lists each reference line the bottom of the web is cut to, such as a cut to the top of each bottom chord. Hover over a cut to highlight its reference line in the scene.

Step 3 - Click the delete icon next to a cut you don't need

A member needs at least one cut at each end, so you can only delete a cut when there are two or more.

Step 4 - Click the remaining cut, then click the reference line you want in the scene

The cut changes to that line, such as a horizontal reference line under the web, and the web is trimmed to it.

Adjust the chord ends

Step 1 - Select a chord that meets the joint, such as B1 under Members, or click it in the scene

Step 2 - Shift-click the same reference line in the scene

The end of the chord nearest the line is cut to it, so the chord ends where the web now does.

Step 3 - Select the other chord, such as B2 under Members, or click it in the scene

Step 4 - Shift-click the same reference line in the scene

Re-analyze the truss

Step 1 - Click Analyze

When the analysis finishes, review the check results again. If the plate pair at the joint now passes, you're done. To view the results, see Run & View Component Analysis.

Watch the video

In this video, the front porch gable truss from Training Plan 3 has a plate pair at 999% at the ceiling vault peak. Changing the cuts where W2, B1 and B2 meet fixes it.

Video Transcript:

In this video we will review the front porch gable truss from Training Plan 3 to address over capacity plating at the ceiling vault peak.

Click to open the C01-GBL, truss from the components list. The first thing we want to do is perform a detailed analysis for this truss. Make sure detailed is checked from the options under the gear icon. Then click analyze. The detailed analysis provides more information regarding what is exceeding capacity which is helpful for troubleshooting and devising a solution.

Now that the truss has been analyzed, we can click on Analysis and History, then navigate to the lower left and expand the Plates section. We see that plate pair number 12 is operating at 999% capacity. Let’s delete the plate and take a look at the ceiling peak joint. It looks like we need to adjust the bottom cuts here where W2, B2 and B1 meet up. To do so, let's select W2, and review the Bottom Cuts from the Properties Panel. Here we can see there are two cuts being applied. We want to delete the B1 Port bottom cut number 2. Then we want to click to select the B2 Port Bottom Cut number 1, and here we will select the horizontal reference line under W2 for this cut.

Next, we need to adjust the end of B1. Select B1, and shift click to select the same reference line we used for W2. We will repeat this for B2. Select B2 and then shift click on the reference line. Let’s re-analyze and see if adjusting the member cuts improved the analysis results of the ceiling peak joint.

Alright - Checks Pass and everything looks good!

Thanks for watching and see you in the next one.