Mast identification

[johnk]

From the current Selden website
http://www.seldenmast.co.uk/dinghy/compare.asp

Fore and aft measurement first in mm
Lambda   63  51
Kappa      67  55  
Cumulus  69  58  
D Plus 3   73  57  
Epsilon    72  57  
Gamma   75  56

[johnk]

Super Spar data from

www.superspars.com with fore and aft dimension second

 M1 55 mm x 68 mm
 M2   57 mm x 72 mm
  M3   57 mm x 72 mm
  M4   57 mm x 72 mm
  M5   57 mm x 72 mm
  M6   61 mm x 74 mm
  M7  57 mm x 69 mm
  M8  55 mm x 69 mm
  M9  53 mm x 64 mm
  M11  68 mm x 86 mm
  M12  73 mm x 95 mm

[Tim Gatti]

Alistair - I have attached some photos of Proctor Alpha and C sections in case you are still trying to identify your spar.
Hope they help.
Tim

[Alistair Edwards]

Tim. Many thanks for the photos. I continue to be amazed at how helpful 12 sailors are!
I am pretty certain the mast must be an Alpha. It has exactly the same rounded profile.
Would I be right in thinking that this is a fairly bendy mast? I am currently trying to repair the mast screw. Just need to find the right threaded rod in stainless steel.

 I think I am going to need the mast screw to maximise power. I am going to be racing with 22 stones + on board.
Once I have done some strong breeze sailing I may try playing with the spreader settings if I need to stiffen the mast.

[Tim Gatti]

Yes - the Alpha is fairly soft - like the C and tha Lamda sections, and you will need some contol at mast gate level to control the bend.
Check out the N12 tuning guide - and dare I say it the Graduate website!! : http://homepages.rya-online.net/graddinghy/@graduatedinghy/gofaster.htm, for tips on sorting spreader length.
Or speak with other 12 sailors more knowledgeable than me on the subject!
I've got to set up an old Alpha in a few weeks time so it would be useful to hear how you got on.

[Alistair Edwards]

I have achieved reasonable control of sideways movement at deck level by packing out each side of the mast slot with thin /light aluminium plant labels. These labels are 20mm wide. Each label is less than 1mm thick so I have got a very snug fit.
 
I suppose it might be better to try and mount them vertically on the mast so as to spread the load over a bigger area. I think for inland sailing the current set up should be OK once I have the mast screw back in place.

Longer term I might fit some lowers. However, I am not sure how easy it would be to adjust a mast screw and lowers together whilst on the water. I could just set the rig up in the dinghy park and leave it alone when sailing.

[Dave Croft]

Alistair,
I think the Proctor Alpha is an excellent mast for a Tigress. Certainly my Cheshire Cat has always gone well with this section. They are fairly bendy above the hounds with good gust reaction (although nothing like as good as the new carbon masts). I have the spreaders fairly high on my rig and you need a very good kicker system but that's probably true of most 12's with hog-stepped masts.
Many years ago at Salcombe I was chatting to Dan Alsop (better known these days in Merlins) about his Tigress and he said that after he broke his Alpha the boat had never gone as well, he recommended I look after my mine!
Regards, Dave

[Alistair Edwards]

So if I did manage to break the Alpha the only logical option would be to fit a carbon mast! A Tigress with a carbon rig might be quite quick.

[THG]

N3143 is already quick when Matt was sailing her!
Tim - hope you're not planning on cutting up the new mast in the same way as the photos here show

[Tim Gatti]

No chance of that - the mast sections are courtesy of Brian Herring - who brought them down to the Dinghy exhibition on Sat.  Luckily, it meant I could photograph them quite easily without chopping up the spars I am trying to restore, which both now need some subtle welding work.
The bit of Alpha is to give me some spare section to repair an area of corrosion I have on the one I hope to use on N341. 
The bit of C section has a very old combined gooseneck/diamonds fitting attached - which Brian thought might help solve my shortage of a sliding gooseneck.  Luckily another N12 sailor kindly brought the genuine item to the show and handed it to me on the 12 stand so I'm half way to getting the C section sorted.
However - I'm stuck until I can locate the guy who said he could do the necessary welding for me - he seems to have disappeared off the face of the earth.  Why is it you can never find a good MIG/TIG welder when you need one?!