How to customize a hanger bolt?

Hanger bolt also know as double thread bolt, the most popular size is M10*200, M10*250, M10*300. Some will use M8 or M12, but it’s not commonly used.

Before talking about choosing size, that’s have a full understanding about hanger bolt.

There are 3 parts in the hanger bolt: Machine thread, Wood thread (hence the double thread) and shank length between 2 threads.M10*200 Total length of the above 3 parts is 200mm. While M10 means the diameter is 10mm.

Then how to install the hanger bolt?

Normally we will drill a hole on the metal roof and the purlin( Usually not penetrate the wood purlin but might penetrate the steel purlin), the hole should be larger than the wood thread diameter but smaller than the machine diameter. The we dill the hanger bolt into the hole with the shank part above the hole. One flange nut above the hole, while the other two nuts one below L feet/ mounting adaptor and the other above it.

Now we can talk about how to customize the hanger bolt

We are using M10*200 Wood hanger bolt as an example:

The length of wood thread should be less than the total length of wooden purlin + roof height. ( Standard 70mm-80mm) While the shank part are just use for EPDM rubber, so around 10mm.

And the metal thread is for the height you would require for the distance between panel and roof since the higher temperature the panel got the lower efficiency it might have. So some would choose with longer thread.

There are 2 types of hanger bolt, one for wooden purlin while the other for steel purlin.

For Wooden purlin, the thread is sharp while the other is flat and smaller than the wood thread to help with easier installation.