[Public-List] Comments about design of the new masthead fitting

[crufone at comcast.net]

Stephen, 



Looking at the photos on the Alberg 30 Web site of the last mast head which was mfg for this group.  I see a bail which is attached to the welded-on crane with four screws.  Is that bail used to attach the turning block for the spinnaker halyard?  Why is the crane offset to the Port side?  I would think that one would want the spinnaker halyard centered on the masthead fitting.  There appear to be four additional tapped holes in the forward upper surface of the masthead fitting, what is their intended use? 



I assume that the main and jib halyards each pass thru two sheaves at the masthead?  How far does the fitting slip down into the mast extrusion,1"?  Could this internal collar be extended to be longer to help beef up this part of the mast? 



I had asked these questions a month ago and I guess my post got lost in the fray.  I don't know if my mast head needs replacing but I do see a couple of areas where the second version could be improved a bit. I don't mean to be hyper critical, that is not the intent of my posting.  If the crane were to be extended directly off the front of the masthead then the spinnaker would be centered on the hoist.  Instead of having the crane weldment to Port, one could just have the top extrusion extend further forward.  This would eliminate the need for the weldment and not interfere which either the halyards or the forestay.  A shackle could be used to attach the spinnaker turning block and thus eliminate the need for the attached bail. Since the top of the fitting would be longer it would provide more surface to mount other gear. 



I don't believe that extending the fitting forward the same distance as the crane would increase the weight aloft much if any.  And the mfg. cost would be less because no fabricated weldment would be necessary. Again, I just wish to make helpful comments and not be bad mouthing your past design work. 



Stephen, thanks for your assistance to this class. 



Michael #133 
----- Original Message ----- 
From: "Stephen Sousa" < alberg114 at hotmail.com > 
To: public-list at lists.alberg30.org 
Sent: Friday, February 20, 2009 6:12:08 AM GMT -05:00 US/Canada Eastern 
Subject: Re: [Public-List] Mast Heads for the Alberg 


Rachel, 

  

The new mast head has four sheeves built into to the unit. The main halyard and jib run into that mast head for full hoist and at that point the sheeve in mast is no longer required. 

  

Hope this helps. 

  

Stephen 
  

 1235139196.0