tiki 30 beams for 26

[paul anderson]

hi everyone i have just read scott williams latest excellent blog and he suggests making tiki 30 beams for the tiki 26 as it is far less complicated to glass and all the structural bits are inside the beam itself.any help or suggestions would be appreciated as always.

cheers paul.

[paul anderson]

well after all the ideas expressed here i have decided to use a hardwood for the timber in the beams it is locally milled here called rose gum or flooded gum,it is the lightest of the local hardwoods.i discovered the mill by accident and it was a pleasure speaking to the bloke who runs the place a bonus being the guy is a sailor and wanting to build his own boat.

[Russell and Janet Puryear]

strength in tension and compression are what matters in the crossbeams.  you might check the properties of that grade gum against spruce to make sure it's not too far off.  Doug fir is stronger, but heavier than spruce.

[boatsmith]

There are many different spruces. When compared  with Doug fir it is usually Stika spruce which is being referred to. Stika spruce is not quite as strong as Doug fir but is lighter and a lot softer. What spruce you find commonly at lumberyards these days here in the states is called white wood and is not in the same league as Stika. It is soft and not very strong.  Stika spruce is available but very pricey.

[Russell and Janet Puryear]

Boatsmith spake the truth, I omitted the Stika, sorry

[paul anderson]

russell as per your advice i looked at the properties of the rose gum in more detail and it seems that it is prone to splitting and not very rot resistant,so for the extra weight penalty the gain is not much.i shall use hoop pine instead.

cheers paul

[paul anderson]

hi all

on the plans for the mast beam i am unclear what the plate with two screws is for,ie is it to cover the access to the bolt that holds the cable for the dolphin striker or is it part of the dolphin striker securing set up?the plans also talk about the removal of the bolt in question ,enlightenment is sorely needed.

cheers paul

[Scott Williams]

Paul, I'd like to help, but I'm not sure what plate you're talking about.  My set of plans is older, but I don't see anything like that shown.

[paul anderson]

Scott there is a drawing on sheet 12c of the mast beam showing the attachment of the 6mm wire with two note one saying'' plate with 2 screws + hole for bolt'' and another '  'leave gap in fairing to inspect +remove bolt''how did you attach your wire to the beam,and i presume there is no inspection plate on the beam itself.

regards paul

p.s how ya'll doing with those fearsome twisters?

[Scott Williams]

Okay, now I see what you're talking about.  That's the metal plate that has two holes for mounting it to the beam web and one hole in the end for a bolt that holds the end of the dolphin stay.  It's like a tang fitting on a mast.  The plans are somewhat vague about the sizing of it, but it would have to be as strong as the stay itself.  The gap in the fairing is a semi-circular cut-out to allow you at access that bolt in the event you need to replace the stay.

 

I haven't fitted a dolphin stay yet, but will likely use Dynex for that, same as my rigging.  On David's Tiki 30 there are heavy U-bolts for the attachment points at each end of the stay and with the Dynex it can be spliced to an eye to make up each end.  I will be working this out soon on my mast beam and posting to my blog, as the beams are now all glassed and just lack final sanding and priming before paint.

 

I will definitely make some kind of cover for the access holes, as well as fit screen or mesh of some kind over the drain holes in the bottom of the beams.  Around here, if you don't do that the wasps and dirt daubers will quickly take up residence inside them.  I found a red wasp nest yesterday in my aft beam, which has been holding the boat together  while I worked on the other two.  These wasps are bad around the water here and on my previous boat they would sometimes build nests inside the mainsail cover and make for a nasty surprise when you got ready to uncover it and raise sail. 

 

The twisters around here have indeed been fearsome, but so far they've missed my immediate area.

[paul anderson]

thanks scott

[Lee Dilkes]

Having just built mast and aft beam for my Tiki 26, yes very fiddly and time consuming but with all the curvy bits = very strong & sexy. Might look at encasing the backs with ply(4.5mm) to increase strength and glassing friendlieness using e glass.albeit utilising a different cockpit mount method.

Bit hard to carbon fibre bottom unless a ply panel is used there also, hmmm interesting idea, just need breather holes for condensation. Weight increase with all extras maybe 10%? VERY strong.

Will be using am aluminium mast section for the Fwd beam as advised by my local rigger/shipwright. Great for tramp mount too, not sure about aft beam yet.

 

[Ian]

Some years ago I made the beams for my Tiki 31, with good quality Douglas fir and 1088 ply, bronze gripfast, and WEST.

For the record, they took a short-week(ie officeworker time) of fulltime work each to make, and I am a woodworker.

They were then sheathed and painted 5 coats with twopack. I think you should build them to last.

They are incredibly strong and resilient. I would just like to mention the hours (eg 300) used for these parts when compared with the overall hours estimated by Wharram Design for the boat- build.