Replacing a mast step on a Princess 18

[Brian and Anne on Princess 18]

I wish to replace my current mast step with a strong and reliable type of bracket and pin mechanism which will enable the mast to raised by one person. The present mast step has a concave cup pointing upwards into which the concave bottom of the mast sits. A photo of the mast step and bottom of the mast is attached. Whilst I do not have construction details for the princess 18 I believe the 4 screws of the mast go through the fiberglass into a pre-stressed beam moulded into the cabin roof. The 4 screws appear to have been smeared with a type of epoxy resin. I believe the only way I am going to carefully remove the screws is by patiently dripping acetone on the screw heads and if that does not work I could try heating the screw heads.

Consequently I would be extremely grateful to hear from anyone who has carried out such a replacement, especially on a Princess 18.

Many thanks

 

[rgranger]

You could probably clean out those screw slots with a box cutting knife.

 

[PaulK]

If they smeared epoxy into the slots on the screw heads, they probably smeared it all over the threads as well, so those screws are likely not going anywhere soon. They may have to be drilled out and replaced with bolts if you build a new setup.

Rather than re-engineer the mast step from scratch, would it make sense to simply extend sides up from the mast step? The extensions could be drilled (along with the mast) to for a pin or bolt to make a tabernacle. The mast would still sit on the same "bump", which spreads the load over a bigger area than a single hinge-pin would. (The side walls of your mast might not be ready for the point-loading that a totally new design, hinging just on a pin, might require.) If you grind down the aft leg of the mast casting you might be able to set the mast in the tabernacle with the pin in place and then lift the mast up up so that it still rests on the step as it did before, with the hinge-pin holding it from slipping forward instead of the aft section of the casting. Good luck!

 

[Brian and Anne on Princess 18]

Many thanks for your excellent advice and for opening my eyes to the concept of the tabernacle.

 

[dlochner]

If they smeared epoxy into the slots on the screw heads, they probably smeared it all over the threads as well, so those screws are likely not going anywhere soon. They may have to be drilled out and replaced with bolts if you build a new setup.

Warm the epoxied screws with a good hot air gun at max temp. The heat will soften the epoxy and it may be possible to back the screws out. The epoxy needs to be heated to around 158° F.

 

[Brian and Anne on Princess 18]

Many thanks but as suggested I think the optimum solution will be to install an appropriate tabernacle and leave the existing mast step alone.