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Mast Arch

Posted: Wed Apr 27, 2016 3:32 pm
by Neo
My 2004 Mac has the mast crutch pole extending out of the helm and I quite like that.

But I now have a 4.5" mast and when I'm preparing to raise the mast and slide it back (on the crutch roller). By the time I get to the deck brackets 2 thirds of the mast is hanging (unsupported) on other side of the roller. This makes me very nervous and I believe this was one reason MacGregor introduced the mast arch, right at the back of the boat.

So I'm looking to have one made up locally (unless anyone has any other suggestions of supporting the mast?). I have the MacGregor engineering drawing and some say that it's a cheap thing to have made up but the SS tube wall thickness is specified at 0.12" (3mm) and thats very pricy tube!

Do you think that 0.12" is necessary?
Are there any alternative methods of supporting the mast or building a mast arch?

All the best.
Neo

Re: Mast Arch

Posted: Wed Apr 27, 2016 6:01 pm
by mrron_tx
Neo wrote:My 2004 Mac has the mast crutch pole extending out of the helm and I quite like that.

But I now have a 4.5" mast and when I'm preparing to raise the mast and slide it back (on the crutch roller). By the time I get to the deck brackets 2 thirds of the mast is hanging (unsupported) on other side of the roller. This makes me very nervous and I believe this was one reason MacGregor introduced the mast arch, right at the back of the boat.

So I'm looking to have one made up locally (unless anyone has any other suggestions of supporting the mast?). I have the MacGregor engineering drawing and some say that it's a cheap thing to have made up but the SS tube wall thickness is specified at 0.12" (3mm) and thats very pricy tube!

Do you think that 0.12" is necessary?
Are there any alternative methods of supporting the mast or building a mast arch?

All the best.
Neo
Neo..... I have an 2011 :macm: and probably have the same size SS tubing. I have My two solar panels mounted on top of the mast support with SS extension tubes at the bottom of each side. The factory ss is tough as nails....You will know if You drill into them.. My recommendation is to spend the bucks and never worry about it during a long / rough tow. Ron.

Re: Mast Arch

Posted: Wed Apr 27, 2016 6:29 pm
by Neo
Good point Ron ;-)

Re: Mast Arch

Posted: Wed Apr 27, 2016 8:15 pm
by Highlander
I made an extension crutch for mine
here,s the original with the bases welded on
Image

Here,s the new one I had made as per the factory spec,s
http://i844.photobucket.com/albums/ab1/ ... 0af196.jpg

I can lower the mast to 4 diff heights , here is a pic before I done that mod in this pic I could only lower to 2 heights
http://i844.photobucket.com/albums/ab1/ ... 010014.jpg

J 8)
PS it was cheaper to get one made locally than buy from a dealer because of freight charges

Re: Mast Arch

Posted: Wed Apr 27, 2016 8:46 pm
by Neo
Can I buy the original one off of you??? .... can you fit it in a she box an post it to me :D

Re: Mast Arch

Posted: Wed Apr 27, 2016 10:29 pm
by Neo
Has anyone ever filled an SS tube with Expoy to strengthen it?

Re: Mast Arch

Posted: Wed Apr 27, 2016 11:34 pm
by kadet
Neo wrote:Has anyone ever filled an SS tube with Expoy to strengthen it?
No but I hammered in a hardwood dowel into my davit posts which are stainless tube 25mmx1.6mm and they don't bend with 50kg hanging off them without the dowel they bent like pretzels :)

If the epoxy is re-enforced with areosil or some other fibres it should be ok (get all the air out). The idea is to stop the tube deforming therefore losing it's structural integrity.

But 3mm tube is just under 2x the price of 1.6mm and for the length say 3M you are dealing with and the with cost of the epoxy you are going to save what $80. I would get the thicker tube. I only used the 1.6mm cause I had it from another project and a wood dowel was like $10. Also use 304 instead of 316.

Re: Mast Arch

Posted: Thu Apr 28, 2016 12:32 am
by Highlander
Neo wrote:Has anyone ever filled an SS tube with Expoy to strengthen it?
Why !!
I roll my mast back on it & i have the extra weight of a 3rd set of shrouds , a second set of spreaders , 2 furlers with jib & genny , 5 sets of halyards & blocks = storm jib , jib , genny, spinnaker, main. 2 extra masthounds , 3 sets of spreader lights , 2 radar deflectors, rigid vang track I,d say my mast is easily 40% heavier than the reg :macm: mast

Just sayin thats all

J 8)

Re: Mast Arch

Posted: Thu Apr 28, 2016 12:53 am
by Neo
Highlander wrote:I have the extra weight of a 3rd set of shrouds , a second set of spreaders , 2 furlers with jib & genny , 5 sets of halyards & blocks = storm jib , jib , genny, spinnaker, main. 2 extra masthounds , 3 sets of spreader lights , 2 radar deflectors, rigid vang track I,d say my mast is easily 40% heavier than the reg :macm: mast
OMG...Loud and clear Highlander, loud and clear :D

Re: Mast Arch

Posted: Thu Apr 28, 2016 12:16 pm
by mrron_tx
kadet wrote:
Neo wrote:Has anyone ever filled an SS tube with Expoy to strengthen it?
No but I hammered in a hardwood dowel into my davit posts which are stainless tube 25mmx1.6mm and they don't bend with 50kg hanging off them without the dowel they bent like pretzels :)

If the epoxy is re-enforced with areosil or some other fibres it should be ok (get all the air out). The idea is to stop the tube deforming therefore losing it's structural integrity.

But 3mm tube is just under 2x the price of 1.6mm and for the length say 3M you are dealing with and the with cost of the epoxy you are going to save what $80. I would get the thicker tube. I only used the 1.6mm cause I had it from another project and a wood dowel was like $10. Also use 304 instead of 316.
Dowels in all of My non stock ss tubing as well as the spreader bars. Ron.

Re: Mast Arch

Posted: Thu Apr 28, 2016 5:20 pm
by DaveC426913
Highlander wrote: I can lower the mast to 4 diff heights , here is a pic before I done that mod in this pic I could only lower to 2 heights
http://i844.photobucket.com/albums/ab1/ ... 010014.jpg
Sorry, Highlander, did you mess up the above link? It be a pic of an oil refinery, like this:
Image

:D

Re: Mast Arch

Posted: Thu Apr 28, 2016 10:56 pm
by Highlander
DaveC426913 wrote:
Highlander wrote: I can lower the mast to 4 diff heights , here is a pic before I done that mod in this pic I could only lower to 2 heights
http://i844.photobucket.com/albums/ab1/ ... 010014.jpg
Sorry, Highlander, did you mess up the above link? It be a pic of an oil refinery, like this:
Image

:D
U only wish ur boat had half of my mods & u,ll never ever beat my price gouging abilities to p/u brand new equip. for next to nothing or half price or less & their r many on this site I have gotton stuff & equip. for @ 90% off & were totally amazed & astonished & thankful when I got involved with them & said what If !! ! :arrow: :?: :idea: & i struck a deal for them !! so there :) :P

just sayin thats all :wink:

J 8)

Re: Mast Arch

Posted: Sun May 01, 2016 1:45 pm
by taime1
I too have the 2004 model and am looking into putting the arch on the aft end. I also got a local shop to price one out using the MacGregor specs. Their estimate is about $240 (CAD) plus taxes. Seems a bit pricey, but I don't think I have many shops around here to chose from. It's probably similar in cost to getting it from BWY, converting the Canadian peso and getting it shipped, so may go that route.

I did get the arch holders from BWY, they seem kinda small to me. The BWY site indicates that I need a spacer to retrofit the carrier to the earlier model, but I'm not sure as to exactly where these are installed, nor how much of a spacer is needed.

Could anyone post a pic of theirs, please?

Re: Mast Arch

Posted: Sun May 01, 2016 2:03 pm
by Highlander
taime1 wrote:I too have the 2004 model and am looking into putting the arch on the aft end. I also got a local shop to price one out using the MacGregor specs. Their estimate is about $240 (CAD) plus taxes. Seems a bit pricey, but I don't think I have many shops around here to chose from. It's probably similar in cost to getting it from BWY, converting the Canadian peso and getting it shipped, so may go that route.

I did get the arch holders from BWY, they seem kinda small to me. The BWY site indicates that I need a spacer to retrofit the carrier to the earlier model, but I'm not sure as to exactly where these are installed, nor how much of a spacer is needed.

Could anyone post a pic of theirs, please?
Yes I think u do because I believe the stern side wall where these go has a halfmoon indent slot in the fiberglass
http://i844.photobucket.com/albums/ab1/ ... 010011.jpg

J 8)

Re: Mast Arch

Posted: Sun May 01, 2016 2:10 pm
by Neo
Great question Taime ... I'm like to know about that retrofit spacer too?.... Could you post up the BWY part number?

I'm having my arch made of SS 316 (Macgregor's Spec is 304) and my SS Tube bender/ Fabricator has quoted me AUD220 (similar rate to CAD) just to supply and bend the tube. But he doesn't do welding so a friend of mine is welding on the ears.....So I don't think your quote is so bad but if you purchase from BWY your shipping cost would be A LOT lower than mine :D

I agree the Socket holders look far too short. I have purchased the some 1 1/4" SS tube and will try an make a better job of that.
I've seen (somewhere) someone selling Socket inserts to make the arch tubes fit tighter ... Have you come across these?

Thanks Highlander, I'll check for that "halfmoon indent"


All the best.
Neo