View Full Version : what type of bolts do you use in aluminium

21-08-2015, 06:56 PM
sorry for all the questions im just designing the build as i go along so i can understand my machine piece by piece :). anyways ive read that you cant use steel bolts in aluminium plates so what do you guys use and what size for 25mm thick plates?



21-08-2015, 11:02 PM
Not sure where you heard that.... as long as you do not strip the aluminium thread you will be fine. The size of the bolt will depend on what you want to screw done.

Granted, in some environments you do not want stainless steel to be screwed into aluminium for galvanic corrosion reason but in most machine builds it is fine.

21-08-2015, 11:11 PM
I've used M8 x 25 BZP grade 8.8 in my gantry which is mostly 20mm Ali plate.

22-08-2015, 08:21 AM
As said, steel bolts in aluminium are fine if it's kept dry. It's something to avoid, if possible, for things like outboard motor legs which live underwater - even stainless bolts can give problems. So unless you are building an underwater router, just go ahead!

22-08-2015, 10:04 AM
thanks guys