Mast size

Expertise and know-how available for all builders from Class Members

Moderators: admin, Kevin

Mast size

Postby slowpoke » Sun Apr 29, 2012 7:37 pm

I just ran into a guy who has a Mercury sailboat with a spare 26' mast. My concern is that the mast is extremely tapered at the top, and they only run fractional spins. Any thoughts? would this mast be too small for the i550?
Rocky Shelton
Slowpoke, #288
Tijuana, Mexico
slowpoke
 
Posts: 365
Joined: Fri Mar 25, 2011 8:36 pm
Location: Tijuana, Mexico

Re: Mast size

Postby M&S » Sun Apr 29, 2012 8:42 pm

Rocky,
If the price is right then it can be made to work. My information is that it is a 24'6" height off of deck spar. Inline spreaders can be changed to swept back and run the uppers to near the masthead and bob's your uncle. But the price has got to be reasonable. Used sails from the mercury can get you on the water for cheap also. There is no shame in running a fractional kite while learning your boat. some of the spars were made by Ballenger a well respected sparmaker.
M&S
 

Re: Mast size

Postby Big_Dog » Sun Apr 29, 2012 9:35 pm

Rocky
I am starting out with a Viper rig and can put my thumb and index finger around the mast head. I'll aslo will also need to relocate the spin halyard and stays to the top.
Jon
Jon
#36 – Still In the Dawg House
Columbia, SC - Lake Murray
Big_Dog
 
Posts: 63
Joined: Wed Apr 13, 2011 4:04 am
Location: Columbia, SC - Lake Murray

Re: Mast size

Postby Chad » Sun Apr 29, 2012 10:09 pm

26' is a great starter length. I think it's about a 25 pound mast, so a little less than a pound a foot. That compares reasonably with the Dwyer sections others have talked about using. Mercury's use forward jumpers and no spin, so you'll be pretty much starting with a bare tube as far as reworking goes.

I have a friend with a Mercury, I'll ask him what he knows about the mast.
Chad
 
Posts: 806
Joined: Fri Mar 25, 2011 7:28 pm
Location: N. E. MO

Re: Mast size

Postby TexLex » Mon Apr 30, 2012 3:20 pm

Big_Dog wrote:Rocky
I am starting out with a Viper rig and can put my thumb and index finger around the mast head. I'll aslo will also need to relocate the spin halyard and stays to the top.
Jon


I too have a Viper mast I will be using. Obviously gonna have to cut it down a little.

I am wondering if I cut the top section down to where the Vipers run their kite from (just below the top) if the mast will be stable enough to run with just the single spreader as it is currently rigged. THOUGHTS???

Big Dog: How are you planning on rigging yours?

Chris
TexLex

Peregrine
Hull 030
http://i550peregrine.blogspot.com/
TexLex
 
Posts: 35
Joined: Tue Mar 29, 2011 3:39 pm

Re: Mast size

Postby Kevin » Mon Apr 30, 2012 8:07 pm

I think it was Tim Carter who figured out that you could trim a viper mast from the bottom and get pretty much right on position for the jib sheave and forestay. But it could be the other way around. I don't remember. That rig is built for a "7/8" fractional kite host above the hounds with single swept spreaders. If you trim from the top, you might be ok with a masthead assuming that it's basically where the kite hoist is currently located. From the bottom and you will need a 2nd set of spreaders to go masthead kite. The viper AL spar is sleeved. That makes it heavy and limits the amount of pre-bend you can dial in.

Good luck with the Mercury rig Rocky. If it gets you on the water and it's cheap then go for it. If he's giving you used sails with the package than you are that much closer to getting on the water.

Cheers, Kevin.
Kevin McDaniel
i550 #074 - PipeDream
Kevin
 
Posts: 457
Joined: Fri Mar 25, 2011 7:11 pm
Location: Evanston, Il

Re: Mast size

Postby Big_Dog » Tue May 01, 2012 7:40 am

Chris,
Congratulation. I see that you have a SB18 to play with in the Houston area. PHRFGB gave Lady C an initial rating was 245, but it has been revised down to 150. No pressure, but you could be the first i550 to race an SB18 design.

As for the mast: I’m planning to position the jib and forestay per the i550 rig dimension. That puts the mast head about 1 1/4“ higher than the i550 sail plan. I talked with a North Sail expert that recommended keel stepping the mast. I will need to cut off 6” – 10” from the bottom end. This also requires cutting out the compression post and building the step at berth height. I see a sawzall day coming.

I also talked to the local West Marine associate, which owned and raced an early Viper. He said that to get pre bend the rig loads are high than other boats he raced. Kevin is correct about the inner sleeve (Butt to spreaders). You could remove it and the Selden 3525 mast is 10% lighter than the Dwyer DM-4. Also you keep the tapered top section. If needed, I’ll could pull the sleeve later, or save for a CF. Also by cutting from the bottom end you are removing more of the heavier sleeved section. I’m thinking that I need to run wires from the mast step to the chain plates to help distribute the extra load. The spinnaker does exit needs to move up 30” (inside or out) and add stays (diamond?) to support the tip.

The Viper mast meets my requirement for a cheap first mast to get off the dock. About half the price of aluminum stick and 10-15% of CF rig. The tradeoff is the weight. 26 feet of mast is 3 lbs less than a DM-4 before adding 8 – 9 lbs of sleeve. Net is 5-6 lbs more. All boats in the SE are using Aluminum rigs.
Jon
Jon
#36 – Still In the Dawg House
Columbia, SC - Lake Murray
Big_Dog
 
Posts: 63
Joined: Wed Apr 13, 2011 4:04 am
Location: Columbia, SC - Lake Murray

Re: Mast size

Postby noemar » Sun Oct 21, 2012 7:28 pm

I am planning on keel stepping a Viper 640 mast on my i550. The plan is to laminate carbon fiber across the beam from chine to chine ,covering with 3/4 "hydro edge plywood then setting an aluminum I beam and then the keel step. I am visiting in Ellicott City MD this weekend returning back to MA tomorrow. I will then dry fit the keel step ,take some photos and send in for opinions.
Thanks,
Noel
noemar
 
Posts: 140
Joined: Sun Apr 17, 2011 12:42 am
Location: New Bedfod,MA Buzzards Bay

Re: Mast size

Postby admin » Sun Oct 21, 2012 10:24 pm

Darn, I was in the backyard all day sanding about 20-25 mintues away. And I have an extra longboard and lots of extra dust masks, too! :D
Viper mast sounds like a plan, cant wait to see the pix.

TF
admin
Site Admin
 
Posts: 474
Joined: Fri Mar 25, 2011 4:17 pm

Re: Mast size

Postby noemar » Mon Oct 22, 2012 7:14 pm

Next time I'm in Ellicott I send you a message
noemar
 
Posts: 140
Joined: Sun Apr 17, 2011 12:42 am
Location: New Bedfod,MA Buzzards Bay

Re: Mast size

Postby Marino » Wed Oct 24, 2012 3:33 am

I've also just purchased a viper 640 mast and would be interested to see the pix's, and what length of spreader(s) you woud be using.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby noemar » Thu Oct 25, 2012 1:31 am

Because I also got a mainsail and jib with the purchase of the mast I will try using the rig as it is. I do not expect to be racing one design so we will see out it goes.
But first I have to finish building the boat
noemar
 
Posts: 140
Joined: Sun Apr 17, 2011 12:42 am
Location: New Bedfod,MA Buzzards Bay

Re: Mast size

Postby Marino » Mon Nov 04, 2013 3:16 am

Need help
Have purchased a viper mast and I am thicking of converting it to s double spreader setup.
Has anyone converted their mast?
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby noemar » Sat Oct 10, 2015 3:29 am

Marino,
Did you ever get a response on converting to a double spreader rig? Spreaders can be purchased at APS in Annapolis but do not know where to get the spreader mast brackets
noemar
 
Posts: 140
Joined: Sun Apr 17, 2011 12:42 am
Location: New Bedfod,MA Buzzards Bay

Re: Mast size

Postby Marino » Sat Oct 10, 2015 3:58 am

Noemar i am purchasing the brackets and spreaders through VELOCITY BOATWORKS.
Mark Stieber has a breakdown of measurements he used on his viper mast on the S.A. i550 forum site. I believe its in one of the last three pages.
Also Ron Bowman on this forum ask about a double spreader system measurements in one of the last pages.
Hope this helps you.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby Marino » Wed Mar 16, 2016 10:27 pm

For those using a viper mast, did you need to purchase a mast step and from whom did you purchase one or did one have to be modified to fit the mast.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby jray » Fri Mar 18, 2016 3:29 pm

I have the measurements for the double spreader setup that Ron did. I did the same on my mast. Don't know how much help it will be as the measurements are for the C-Tech carbon.
Jon
#061 Critical Twist
jray
 
Posts: 531
Joined: Fri Mar 25, 2011 6:26 pm
Location: Polson, Montana

Re: Mast size

Postby Warren Nethercote » Sat Mar 19, 2016 1:46 am

Marino, have you considered making or having made a C-Tech style mast step to carry the bare Viper tube? It should work just as well for aluminum as for carbon. There are various pictures of the C-Tech mast step about. You could start looking in Chad's build log. I am on the road at the moment, otherwise I would attach a photo that I downloaded to my desktop.
Warren Nethercote
Boutilier's Pt, Nova Scotia
Build License 573
Build log: viewtopic.php?f=3&t=364
Warren Nethercote
 
Posts: 408
Joined: Sat Apr 25, 2015 2:11 am

Re: Mast size

Postby Marino » Sat Mar 19, 2016 3:00 am

Thanks Warren, will check it out.
Also to Jon, thanks for the info on the double spreader measurements.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby noemar » Sat Mar 19, 2016 2:40 pm

Marino,
I am using a alum. Viper mast but it will be stepped below. Try the Selden catalog for deck stepped mast step also you might want to try www.apsltd.com. They carry many Selden parts which fit Proctor masts There are also a couple of suppliers in Great Britain that are a good source for Selden mast and boom parts.
www.coastwatersports.co.uk or www.sailboats.co.uk A little pricier due to exchange rate and shipping, but if you need it and they have it you pay . No one said building a boat was cheaper. Good luck finding whatever you need.
Noel
noemar
 
Posts: 140
Joined: Sun Apr 17, 2011 12:42 am
Location: New Bedfod,MA Buzzards Bay

Re: Mast size

Postby noemar » Sat Mar 19, 2016 2:43 pm

Marino,
I never did find the measurements for setting up a double spreader rig.
Noel
noemar
 
Posts: 140
Joined: Sun Apr 17, 2011 12:42 am
Location: New Bedfod,MA Buzzards Bay

Re: Mast size

Postby Marino » Sat Mar 19, 2016 5:31 pm

Thanks Noel for the info for the mast.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby Marino » Sat Apr 09, 2016 3:20 pm

Any suggestions as to how to remove the inner sleeve in the viper mast. Rivet holes would be filled with rivets again and sealed with silicone.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Re: Mast size

Postby micah202 » Wed Apr 20, 2016 4:32 am

Marino wrote:Any suggestions as to how to remove the inner sleeve in the viper mast. Rivet holes would be filled with rivets again and sealed with silicone.



....sounds like you're the one 'in the know' now! congrats!
i550 #240 ''carbon offset'',vancouver,BC,Canadah
......please be surre to user a resperarator ,espectially doing largger areasa of epoxy.
.....utherrwise,yerulll endap takling uhnd rithing rike ah do--NAHT GUD,ehnytime
micah202
 
Posts: 390
Joined: Tue Jul 26, 2011 2:34 am
Location: vancouver BC

Re: Mast size

Postby Marino » Wed Apr 20, 2016 6:32 pm

Have removed the inner sleeve in my viper mast. with the suggestions offered by Michael and a few extra steps that were found to be needed, I was able to pull the sleeve out.
Unable to post picture, size of picture exceed the limit allowed. Will try at a later date to post some pictures and a description of the steps involved.
Marino Zorz
Toronto, Ontario
Build License 307
Build log: http://photos.app.goo.gl/M2m7Afvf2f8p35nz5
Marino
 
Posts: 174
Joined: Fri Jun 10, 2011 2:23 am
Location: Toronto, Ontario, Canada

Next

Return to Building an i550

Who is online

Users browsing this forum: No registered users and 2 guests