Dynamic Block for Adjusting Thread Lengths

[noe_pardoen]

Hello everyone,

I am working on setting up a Dynamic Block in AutoCAD for DIN 931 ISO 4014 INOX A4 bolts, ranging from M4 to M36. I am facing some issues with dynamically adjusting the bolt and thread lengths based on specific parameters. Any help would be greatly appreciated!

Here’s my situation:

1. Objective: I want the thread length to automatically adjust depending on the bolt length. For example, with an M6 bolt, the thread length should change from 18 mm to 24 mm when the total bolt length exceeds 120 mm.

2. Current Setup:

   • I am using multiple Lookups to manage this. Lookup 2 and Lookup 3 allow me to select the desired view and M-size.
   • In Lookup 5 and Lookup 6, I have set up dual Lookups. Lookup 5 links various options to the visible name of the bolt, while Lookup 6 connects these names to their corresponding Visibility States.
   • This setup works well and is organized, with multiple tabs for easy access.

Where I Need Help:

Now I want to extend this functionality to all sizes from M4 to M36. However, I am running into issues with the Block Properties Table:

1. I can’t add multiple properties tables within a single block, which means I can’t specify lengths for all bolts (M4 to M36) without complications.
2. When trying to include sizes for both M6 and M8 bolts in the same table, empty cells appear, causing the table to malfunction if all cells aren’t filled.
3. Additionally, I can’t reuse the same size specifications for different bolt sizes. For example, the largest size for the M6 bolt is 160/24, while for M8 it’s 220/28. This means I either need a separate table or a way to "freeze" parameters, or a command that adjusts the thread length automatically once a specific measurement is exceeded.

Attached Link: I’ve added a link showing how the thread length changes in the table for reference.

https://www.traceparts.com/nl/product/bene-inox-boulonnerie-visserie-inox-410102-vis-a-tete-hexagona...

If anyone has experience with dynamic parameters or multiple Block Properties Tables for similar use cases, I’d greatly appreciate your insights. Also, if there’s a workaround or command that automatically adjusts the thread length when a specific length is exceeded, I’d love to hear about it.

Thank you in advance for your time and help!

[j.palmeL29YX]

I'd try to solve the issue with one Block Propery Table. 

Attached an example which allows you (I hope) to undertand my thoughts. The table is filles with fictive values, of course you must adjust and complete these. And for the both standards DIN and ISO I used the same value (I think in reals they are really nearly identical ?) . 

Give it a try and et me know if you have further questions. 

[noe_pardoen]

Thank you very much for helping me! I think it’s a great example, but could you explain how the table works? I don’t fully understand how everything functions. I can adjust and see the standard, size, and length, but the other four items in the table aren’t displaying. I tried to "break" the block to figure out what was causing the issue, but you've secured it so well that I can’t quite get it to work.

I would like to adjust the block to a top view and front view, since DIN and ISO are the same in this case. I only started working with Dynamic Blocks a week ago, so there’s probably a lot I still don’t know. If you have any further tips, I'd really appreciate them!

[j.palmeL29YX]

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@noe_pardoen wrote:

I can adjust and see the standard, size, and length, but the other four items in the table aren’t displaying.

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And that is how it is intended. If I were the user, I'd expect to be able to choose a standard, a nominal diameter and the length, the remaining geometry should be adjusted automatically.
I'll try to explain on the simplified example "screw" which I posted above. Again, the numbers in the table are fictional, they must of course be substituted and completed with the real values you need. 

How to add the top view I'll show in a second video tomorrow. 

[j.palmeL29YX]

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@noe_pardoen wrote:

I would like to adjust the block to a top view and front view, 

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Attached a file  example how that may be done (it is one of several ways). 

[noe_pardoen]

A big thank you to the person who helped me with my dynamic block for DIN 931 ISO 4014 INOX A4 bolts (M4–M36)! Thanks to your help, the automatic thread length adjustment is now working perfectly.

One small note: the base point for the Front view should actually be placed elsewhere. However, due to the constraints that move everything, I can't add a move action to position the bolt itself correctly.

Thanks again!

[j.palmeL29YX]

What about adding a basepoint parameter? 

[noe_pardoen]

Could you clarify what you mean exactly?

Are you referring to a move parameter that anchors to a base point, or do you mean something else?

[j.palmeL29YX]

Assuming you want an other base point, e.g. on the top of the head (I don't belive that, but only for demonstration) follow the steps in the video. 

[noe_pardoen]

I just made a video to show what I meant about moving the base point. I want the base point to always stay on the centerline, but when I try to move the section below the head to a new position, it shifts to a completely different location. For example, I couldn’t get it to move by exactly 0.25 at M6, and on certain lengths, the section even ended up above the head.

[j.palmeL29YX]

See attachment. 

HTH

[noe_pardoen]

Hello everyone,

I’m facing an issue with the display of countersunk bolt lengths in AutoCAD. The table is correct and shows the right lengths for the bolts, for example, 25 mm for M16, but the actual bolt length doesn’t match the table. This is because the head size in larger M sizes (like M16, M20, etc.) is larger than in M3, which increases the overall length of the bolt.

For example, the M16 bolt is supposed to be 25 mm according to the table, but due to the larger head size of the M16, the actual bolt length becomes 32.15 mm (for instance). The problem arises because the head size of the larger M sizes affects the total length of the bolt, while the table itself is correct.

What I’m trying to achieve is that the total calculated length of the bolt remains equal to the value shown in the table, even with the larger head size. The top of the head must always stay in the same place so that the thread length is displayed correctly and the total bolt length matches.

Does anyone have tips or experience on how to solve this issue? How can I set the thread length correctly without the head size affecting the total length?

Thanks in advance!