Attaching Gas Struts to Mast

[Colin Stone]

An engineering Q. I have 2 gas struts to lift my mast on a Dutch barge. At the moment, its only purpose is lift the mast head light to the correct COLREG height, fly flags and look impressive. I could use it to fly a small steadying sail, say 3 x 4 triangle.

Originally, I decided to use exhaust clamps at the mast end so I could fine tune the vertical position on the mast. After a full season using the struts, the position is spot and I'd like to make the fixing arrange a little less heath robinson and neater.

My idea, without doing a welding job, is to drill holes in the mast walls and fit 8mm internal thread to 10mm external thread converters in the wall with an 8mm threaded rod between them in the mast. Then fixed in mast with standard nuts and lots of JB Industroweld as I assemble to fix the thread converters in the mast wall. The 8mm ball extensions will screw to the outside end of the converters to take the strut ends.

Below is a pic of the current exhaust clamp arrangement and a drawing of my idea.

And Loctite 738 on all the various threads to stop anything moving.
The 8mm ball extension will permit the use of 1200N gas struts instead of 700N, so make lifting even lighter.

Wondered if I had missed anything or any thoughts?

[Benz]

Should work fine. Do you have a locking pin or means of holding the mast up in case the shocks fail?

[leecea]

If the mast is aluminium and the fittings stainless steel, as I understand it, you might need to consider galvanic corrosion between the two metals.

Perhaps the JB and Loctite products you mention take care of this, or perhaps you are in fresh water - I'm not an expert on this, so hopefully someone else is!

[Colin Stone]

... locking pin or...
Yes, there is a drop down bar on the front of the tabernacle.

... aluminium and the fittings stainless steel...
I'm pretty sure they'll be fine. Aluminium yacht masts are smothered with SS fittings.
And inland fresh water based.

The mast replaced a 6" x 6" 6.1m Douglas Fir mast which had started to rot. Now maintenance free.