I thought I should post my experience  in resolving an issue of fixing a broken stanchion post to maybe help others. 

My stanchion post is the type that has a solid top inserted into the stanchion which is held in place by a 6 mm bolt and the lower part of the post being a threaded 12mm rod inserted through the deck into an aluminium insert. Interestingly web site search indicated one type where the rod is threaded into the top section of the post and the other being machined unit from a solid blank of which mine was the latter.

The post is the solid section that my stanchions fits over - I visited my boat last week and found one of my stanchions unattached for what ever reason (“friendly” fend off by visiting boat or just past its use by date etc etc) - it was snapped off at deck level under the 2mm washer!

I sort advice from both Australian distributors and also Hanse as to how I could remove the stud and in both cases they only provided me with a variety of replacement types but not what I sort, ie how to get the stud out.

In the end I was satisfied from various posts on this site that the post is held in place via an aluminium plate that has been threaded and no bolts underneath.

To remove the threaded part of the post  I used a small diameter angle grinder cutting disk with a diameter of aprox 60mm (ie has been worn down after use from original 100mm size) and cutting width of less than a millimetre to create a slot across the top of the exposed threaded rod. I found that the electric grinder tool I was using was a bit too hard to hold on the the exposed head due to its power/torque so changed to a small battery grinder with far less torque that only took 50 mm cutting disks and was more effective however I did have to cut into the gel coat surface to get sufficient slot depth

It was a 2 man job to remove the threaded rod with one person pressing down heavily on top of an 8mm bladed screwdriver whilst I turned an 8 inch adjustable spanner attached to the screwdriver just above the top of the base. 

I had applied WD40 to the post a couple of times over previous day to help with potential electrolysis issues but don’t think it was necessary as when we finally removed the threaded bolt there was no sign of electrolysis but there was a little bit of sika on the tip- the first movement was very challenging with first movement only about 1 mm -ie revolution -  eventually we achieved one full turn and I then made a slightly deeper cut with the angle grinder - this additional depth gave as much better screwdriver grip and eventually it came out.

Bottom line, I think I should have made a deeper cut and not be concerned about gel coat damage as most of area is hidden by the washer and easily repaired. I would also ensure that no WD 40 residue remained as it seemed to make the screwdriver slip out until we wiped the bolt as well as we could. I should have also used the small angle grinder from outset as it was far easier to control than the electric unit.

I would not order required replacement unit until all removed as the length of shaft was different in the 3 replacement styles offered.  Although I am fortunate that our local rigger is a good friend and he is going to drill a new hole in the actual above deck mounting post and instal a new section of threaded post in line with the style of one of the replacement units. 

If I had recently purchased a new boat I would remove each post and then run lanolin grease over the threads and reinstall and then apply sika over last 10mm of exposed thread under the washer to minimise water penetration and mainly help with removal if a post may be damaged at some  future time. My rationale being that I didn’t sleep too well on the night after finding the problem as I tossed and turned trying to resolve issue and then when I first tried to remove the broken section on my own it wouldn’t budge until a friend helped me the next day.

Peter