quickrelease

j105 sparcraft mast issues

Recommended Posts

I have a four year old Sparcraft replacement mast on my 105.  The  spinnaker halyard has a masthead sheave and then travels down the forward face of the mast to a "halyard retainer" which sets the halyard at the its class legal height.  This fitting is riveted on the mast, and it was re-revitted by the J boat dealer  this past summer, with bigger and stronger rivets, and the POS thing still is wiggling and has 1/4 inch of play - see the picture and video.

 I hope it doesn't pull out in 25 knots of breeze.  Sparcraft has been less than helpful and I see that they have a one year product warranty.  What to do?  Anybody else have this problem?

retainer1.JPG

Share this post


Link to post
Share on other sites
1 hour ago, quickrelease said:

I have a four year old Sparcraft replacement mast on my 105.  The  spinnaker halyard has a masthead sheave and then travels down the forward face of the mast to a "halyard retainer" which sets the halyard at the its class legal height.  This fitting is riveted on the mast, and it was re-revitted by the J boat dealer  this past summer, with bigger and stronger rivets, and the POS thing still is wiggling and has 1/4 inch of play - see the picture and video.

 I hope it doesn't pull out in 25 knots of breeze.  Sparcraft has been less than helpful and I see that they have a one year product warranty.  What to do?  Anybody else have this problem?

retainer2.MOV

retainer1.JPG

Your JBoat Dealer Riveteer might stink at riveting 

Share this post


Link to post
Share on other sites
2 hours ago, Rasputin22 said:

.025" on a feeler gauge is a long way from 1/4" play as stated.

j73QUGr.jpg

  • Like 1

Share this post


Link to post
Share on other sites

Rivets can and do stretch out  We've had similar issues with 1/4" rivets holding the backing plate for our mainsheet bail.  Is the mast wall thick enough to just tap or helicoil for machine screws?  Another option might be Riv-nuts & machine screws, but I don't have any experience with them.

Share this post


Link to post
Share on other sites

are you sure it was riveted correctly in the first place. larger rivets on that fitting can be a problem to install because the rivet gun head is to large in diameter  to get the gun on straight causing a the rivet to be set at an angle and then they come loose. takes a modified gun head to set on that fitting. I installed the same on my spinnaker halyard and had to make a special gun head to rivet it. milled flat on one side. 

The Spacraft fitting is made for flat head screws with a 90 degree head  ( metric ) in there catalog they have  picture of the 6 screw fitting installed with very poor craftsmanship using button head screws instead of flatheads and not even centered in the hole on the fitting.. must be proud of the shitty work to use that pic in the brochure.  http://www.sparcraft.com/uk/products/hardware/fichiers/mast_accessories.pdf

Best would be to use screws with a threaded backing plate inside the mast.

I know that is not easy but how much is it worth to keep the spinnaker flying.

Share this post


Link to post
Share on other sites

yes, a backing plate or thru bolts, or a proper halyard sheave would be ideal, but what is the next best choice? 

Set it up with metric screws and tap some holes in the mast, drop in some locktight and hope for the best?

As far as the feeler gauge goes, i was only off by a factor of 10, which is not bad for government work.  And  I feel sorry for that Rasputin guy who is fixated on penis size - maybe if we multiply by 10 he can finally have a 10 inch dick.

  • Downvote 1

Share this post


Link to post
Share on other sites

Great way to start Newbie! See where that gets you. I'll be sure to be sorry for you when your mast falls down. Not really but hope you get the point.

2 minutes ago, quickrelease said:

yes, a backing plate or thru bolts, or a proper halyard sheave would be ideal, but what is the next best choice? 

Set it up with metric screws and tap some holes in the mast, drop in some locktight and hope for the best?

As far as the feeler gauge goes, i was only off by a factor of 10, which is not bad for government work.  And  I feel sorry for that Rasputin guy who is fixated on penis size - maybe if we multiply by 10 he can finally have a 10 inch dick.

 

Share this post


Link to post
Share on other sites

    I have had discussions with my sparmaker about using helicoils about this sort of use but he thinks they mash up the carbon threads needlessly. However I like the look of this use in a CF mast.

 

Share this post


Link to post
Share on other sites
9 hours ago, quickrelease said:

I have a four year old Sparcraft replacement mast on my 105.  The  spinnaker halyard has a masthead sheave and then travels down the forward face of the mast to a "halyard retainer" which sets the halyard at the its class legal height.  This fitting is riveted on the mast, and it was re-revitted by the J boat dealer  this past summer, with bigger and stronger rivets, and the POS thing still is wiggling and has 1/4 inch of play - see the picture and video.

 I hope it doesn't pull out in 25 knots of breeze.  Sparcraft has been less than helpful and I see that they have a one year product warranty.  What to do?  Anybody else have this problem?

retainer1.JPG

Those rivets don’t all look the same, and as others have mentioned, they almost certainly haven’t been riveted properly and you can’t measure for shit. 
 

Welcome to SA. 

  • Like 1

Share this post


Link to post
Share on other sites

ok, so i can't measure - the fitting jiggles around like crazy despite factory rivets and dealer rivets.  I did not realize there was such a big nuance to rivets and riveting in the first place. 

That backing plate on a CF mast - it looks like you have to make a hole the size of a shark bite to place the sheave, that doesn't seem that structurally sound either.  Is there a trick to getting a backing plate inside a mast, without tearing a hole in it? Please share the secret.

 

Share this post


Link to post
Share on other sites

Could this be rigged with a partial collar of sorts so that the fasteners get loaded in shear?

Share this post


Link to post
Share on other sites

Just tap the holes and drop in some short machine screws.  Take caution with internal running rigging.  TEF-GEL them for dissimilar metal corrosion purposes and Bob's Your Uncle.  Check them every time you check the rig.  Even if you use stainless pop-rivets they will stretch.

Share this post


Link to post
Share on other sites

Get two, turn it into a ketch.

Share this post


Link to post
Share on other sites

It's a step up from the Hall mast implementation. They used a sawzall to hack an oversized rectangular hole (with sharp corners) out of the front of the mast section at it's highest stress location and bolted the sheave in using #10 stainless screws into the aluminum. 

Share this post


Link to post
Share on other sites

One thing you could do would be to make an oversized aluminum or stainless plate shaped to the section. Bolt the fairlead to the plate and then rivet the plate to the mast with more than 4 rivets and space to use the rivet gun properly. Or, if you go stainless with the plate, have someone weld a 1/4" dia hoop to the stainless plate and use 6 or 8 screws/rivets to hold the plate to the mast.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now