LVL lamination connections

[sinneDP]

Greetings all-

I am trying to add fasteners to a dynamic block of multiple plies of LVLs. Ulitmatley I would like to have it with either bolts or SDS screws in section. Through bolts in section seem to be easier and pretty straight forward. SDS screws are not so easy.

Here is background on the SDS screws-



And here are some assembly examples-

Attachment 104824



I am trying to figure out the best approach. The LVL's are all 1-3/4" thick. The screws are either 3-1/2", 4-1/2" or 6" long with thread lengths of 2-1/2", 2-3/4" and 3-1/4" respectively.

There can be either 2 rows or 3 rows of screws. The two row condition the screws are set 1-1/2" from the edge of top and bottom. The third row is on center (not shown in the pics).

I am trying to figure out if its better to use a visibility state with fixed number of plies or have dynamic screw lengths based on a lookup.

Are there efficiencies doing it one way or the other? The dynamic screw length is not so clear to me right now because the increment is not the same step as the screw length.

Has anyone tried something like this? Any advice?

Thanks in advance

sinneD

[MMccall]

Interesting ... ok, if I'm understanding it right, you'll have 8 possible LVL plies and bolt arrangements with the height of the LVL incrementally variable based on available sizes. LVLs are all the same width. Bolts are 4 possible lengths/threads and either in a 2 row or 3 row pattern.

I would approach this by trying to keep it as simple as possible. Array the LVLs and use a stretch action for their height. Set up 8 visibility states for the bolt pattern/size. Re-use the same parameter for the LVL stretch action for a move action for all the upper bolts. Re-use it again for a move action for the middle row of bolts but with a distance multiplier of 0.5. That should give you all the necessary pieces to add to a table for arranging all the expropriate combinations.

I would first set up LVLs. Draw in 1 LVL in the smallest height that would require a 3 row bolt pattern. Array this LVL with a horizontal linear parameter at a 1-3/4" increment. Set their height with a vertical linear parameter with a stretch action. Table those parameters and fill in the appropriate values based on product availability. (Note that we drew in the first one at a size that was available and would be in the table. This keeps the table from being forced to have a 'custom' size to accommodate how it was actually drawn) Add in the 8 bolt pattern visibility states. Make them all visible at the same time and add the two move actions to move them as the LVL height changes. Last, build the table of size values matched with a corresponding visibility state.


Update:
Re-reading this morning I noticed the bolt vs SDS screw scenario. This would add 2 more visibility states (2bolt,3 bolt), a streach action for them added to the horizontal parameter, and the addition of a user parameter to allow for selecting bolt vs SDS.

I picture the finished block with a grip for the width (plies), the height, one for bolt/SDS, and a flip grip.

[sinneDP]

The LVL definition for height and number of plies I have workd out, it's just a couple of lookups.

I am having trouble figuring out the overhead and resulting file size for all these elements as visibility states. Is there any documentation on block effieciency?

I am thining of using graphic liberty to simplify the thread lengths on the SDs screws to make it a simple stretch on the shank, or an array function on the threads.

[MMccall]

I'm not sure if the file size is effected much by by the method used to make something work. Obviously a lot of items in many visibility states would be larger than a single adjustable one.

Sometimes while working on a block the file size seems like its getting bigger than it feels like it should be. I wblock it out and it usually gets much smaller.