After a lively sail in the Gulf of Mexico in 4 to 6 foot seas and 18 knots of wind, we tucked into an anchorage behind Matagorta island. It wasa little rolls and inward some thing banging around inside the mast. Was hard to sleep with all that banging and lancing going on. In the morning I started investigating. I found that by looking through the variouse halyard entry/exit openings in the mast I could see Avery conduit moving around and the banging coincided with the movement of the conduit. I also noticed that there are aluminum pop rivets along the forward port side of the mast. I presume the these we're used to fasten the conduit to the inside of the mast. I am assuming that old age, corrosion, and all those waves in the gulf caused a few of those rivets to let go.
The question I have for all of you is how do I go about reattaching the conduit, preferably without pulling the mast. Has any one noted what kind of clamp goes around the conduit? A picture would be great. Anyone about to pull their boat and un step their mast for the winter, be willing to post some pictures?
Paul : I hate to tell you, but I believe that you are in for pulling the mast to fix/resecure that conduit. I've had my mast down and believe the pop rivets are just thru the mast and into the PVC conduit.
My thought
Paul,
I too have that problem. I pulled the mast last weekend for the winter (haulout already next weekend :cry4`) With the mast on horses, I checked the conduit and it is loose. The sound it made when I rattled it sounded like most of the rolly nights that we've had at anchor for the last couple of years. I didn't notice any rivets along the mast but I'll check again tomorrow when I'm up to the boat. I've got until next spring to come up with a fix so I won't do anything hasty until I research this a bit more and hopefully others will weigh in with their solutions.
The best description I've seen about how to attach conduit to a mast is in Don Casey's book This Old Boat. I've never researched it on the internet.
Hi Dave,
Thanks for the reply. If you could take a picture looking up the mast and post it that would be most helpfully.
Stu, thanks for the reference to Don Casey. I have the book at home and when we get back home from our cruse down the Texas coast I will read that part.
Ron, I can't imagine the rivets go right into the conduit otherwise any wire pulled through the conduit would hang up. Unless the rivets did not go all the way to the inside of the conduit and that may explain why it came loose. Three years ago when we put the boat back together after hurricae Ike, I ran a new wind instrument cAble through the conduit using the old cable as a pull string. Had very little trouble doing that.
To lessen the noise, I have fished a coat hanger around the conduit through one of the jib halyard entry/exit ports and pulled the conduit tight against the inside of the mast. The conduit still slaps the mast some so the attachment point near the top must also be loose.
Here is a pic of mine looking in the base. Like Ron said, pop rivets go directly through the conduit. You can just see one out of focus at the very bottom. The rib along the right side is the sail track.
Ken
As noted, pop rivets will be semi-flush, so Ron's description is accurate. I'm conserving if you couldn't make some "question mark" shaped hooks, and feed them in the rivet holes for a temp restraint? Maybe alum or S/S welding rod. Not sure the diameter of the holes, however.
Quote from: pablosgirl on September 27, 2012, 07:41:43 PM
Hi Dave,
Thanks for the reply. If you could take a picture looking up the mast and post it that would be most helpfully.
Stu, thanks for the reference to Don Casey. I have the book at home and when we get back home from our cruse down the Texas coast I will read that part.
Ron, I can't imagine the rivets go right into the conduit otherwise any wire pulled through the conduit would hang up. Unless the rivets did not go all the way to the inside of the conduit and that may explain why it came loose. Three years ago when we put the boat back together after hurricae Ike, I ran a new wind instrument cAble through the conduit using the old cable as a pull string. Had very little trouble doing that.
To lessen the noise, I have fished a coat hanger around the conduit through one of the jib halyard entry/exit ports and pulled the conduit tight against the inside of the mast. The conduit still slaps the mast some so the attachment point near the top must also be loose.
Paul : Even if you have the mast down, I'm not too sure what to tell you on how to reinstall new pop rivits?!?
I'm not to sure how it was originally manufactured ?? They must have some way to hold/press the conduit against the inside wall of the mast as they drilled and installed the pop rivets!?! Let me keep on thinking about the "how to"?
Thoughts, but no solution
A long piece of flatbar, EMT or tube, run through the conduit as a "strong back" could keep the conduit against the mast as they sequentially drill and rivet, during original manufacturing.
Quote from: Ron Hill on September 28, 2012, 03:24:40 PM
Paul : Even if you have the mast down, I'm not too sure what to tell you on how to reinstall new pop rivits?!?
I'm not to sure how it was originally manufactured ?? They must have some way to hold/press the conduit against the inside wall of the mast as they drilled and installed the pop rivets!?! Let me keep on thinking about the "how to"?
Thoughts, but no solution
Paul : Ed has the ultimate solution on how to hold that PVC conduit(tubing) in place while you drill out the old pop rivets and install new ones.
You've got to pull the mast and might want to try this.
Get the mast on sawhorses. The get a 20 ft long 2x8 which you might need to plane some off to fit. Shove it in from the bottom leaving enough to grab to pull it out. It should wedge itself to hold the PVC in place. Remove and replace the old rivets - new holes? your option. Then remove the mast cap and do the same from the top of the mast. Don't forget to get new BB sheaves from Garhauer to replace the old ones. You might want to look at and replace the old wiring - anchor light/VHF/Hinkley TV antenna/deck/steaming light. Check the goose neck on the boom. Might even think of a new paint job if you are so unfortunate (like me) to have a painted mast&boom!
A few thoughts, Good Luck
I like Ron's idea on the 2x8 as a wedge against the conduit.
I have been doing some internet research on this and through a Google search on "attaching wire conduit inside mast", I came up with the follwoing links that were helpfull:
http://forums.sbo.sailboatowners.com/archive/index.php/t-83549.html (http://forums.sbo.sailboatowners.com/archive/index.php/t-83549.html) - The last entry by Moody Buccaneer was particularly good.
http://www.sailnet.com/forums/gear-maintenance/73532-electrical-wires-inside-mast-making-much-noise.html (http://www.sailnet.com/forums/gear-maintenance/73532-electrical-wires-inside-mast-making-much-noise.html) - The last entry by GaryHLucas was a good idea on using fom blocks to wedge the conduit into place again.
http://www.cruisersforum.com/forums/f55/installing-a-conduit-in-an-aluminum-mast-61324.html (http://www.cruisersforum.com/forums/f55/installing-a-conduit-in-an-aluminum-mast-61324.html) - the third entry by Beausoleil explains how to add a conduit to a mast and the sixth by cwyckham explains how to repair a loose attachment point. Looking at my mast one of the attachment points has two rivets 2" appart horizontally, which explains that this may have happened before and was repaired. This thread also mentions using alloy clamps to hold the conduit to the mast. But this might need the mast off the boat to get this to work.
I plan to try to re-attach the conduit at the double rivet point this weekend and I will post the results. I will first drill out both rivets and then use a stiff wire bent into a "j" hook and feed that through the hole that is off center from the line of rivets going up the mast. I will then pull the conduit against the mast with the j hook and try to place a pop rivet into the second hole and into the conduit. Probably sounds easier that it will be to execute on a standing mast. But, nothing ventured nothing gained. And I really don't want to pull the mast this year.
Paul
Sorry to dredge up an old topic, but we too have this problem and would like to tackle it with the mast up. Paul- Did you ever have success with your technique?
I had this same issue last season. In one of the spare halyard openings I was able to stick a large screwdriver into the halyard opening and force the conduit against the front of the mast. By doing this it stopped the banging so I knew if I could attach something at this point it would work for me.
I inserted the screwdriver again to force the conduit to the mast. While holding the conduit in place, I drilled a small hole in the mast and conduit. Once I felt the drill bit go through the mast, I slowed it down a bit while going through the PVC conduit. I didn't want to drill into the wiring. Once the hole was drilled, I inserted a screw into the hole. I filed down end of the screw so there wasn't a pointy end rubbing against the wiring. Has worked so far. Someday when I drop the mast I'll fix it better but it works for now.
mregan
Sounds like a great temporary solution. You had good luck by not damaging any wiring inside the conduit. If you eventually drop the mast to finish the job, I did this last spring and wrote it up here.
http://c34.org/bbs/index.php/topic,7170.15.html (http://c34.org/bbs/index.php/topic,7170.15.html)
The halyard openings are key to a positive result with the mast down too.
Dave
Good solution. On my previous C-30 the wires weren't even in a conduit, when I pulled the mast to route the halyards internally, I found the factory had stuck a large sponge (with a string attached) into each end of the mast. At the top it was stuffed about 3' down, at the bottom another was stuffed about 6' up. When I installed the halyards internally, I was able to keep the top sponge in place by cutting our 2 sections for the hayards to run through. At the bottom, i pushed the sponge up below the halyard openings. With the string on it, you could pull it down if ever needed. Never had any slapping. You could probably do the same on the 34 which might help the rivets from popping again in the future.
Replacing my conduit with a larger size and rivetind it was tedious but easy by tipping the spar so the conduit nestled "into the groove" while pop riveting. Went slow and deliberate, one by one and doubled the number.
One woulda shoulda that I didn't --- an occasional coupling will more than double the bite on holding w longer rivets.into the heavier wall section. Securely fasten the top w/ additional\closely spaced rivets so flapping doesn't get a place to take hold.
Ken
Tackled this today with what I can only call partial success. Inspection of the rivets above deck revealed one at the middle halyard exit, one at the steaming light and one a few feet from the top. Not a surprise that it would pull loose. Started by removing the halyard exit plates to reveal large"ish" slots on the port and starboard sides. These were easily removed by drilling out the 3/16" rivets. With these removed it one can see what was going on. The conduit at this point of the mast was resting on the starboard side. Drilled two new holes, one over the other, a foot apart, a foot below the lowest OEM rivet, on the port-side, front, inline with the old rivets. Used a long screwdriver in the port-side halyard hole to nudge the conduit to its home position, then used another long screwdriver on the starboard side to press the conduit against the mast. Then CAREFULLY drilled through the conduit. Riveted the conduit to the mast using the screwdriver on the starboard side to provide the necessary pressure. 3/16"x 1/4" rivets were long enough. Reinstalled the halyard plates and went to check on my work. Using a halyard I was able to seriously rock the boat. The difference was remarkable, but on the really big swings- noise could be heard from the upper part of the mast. Climbed back up, this time to the spreaders. There is no access there, but there is a pad-eye fitting for a spinnaker pole halyard. Removed the fitting and used a flashlight to try to get some view. The only thing visible was the jib halyard. Using a stiff wire, found the conduit on the port side in a forest of halyards. Tried to pull it snug, but it really resisted. I didn't feel comfortable riveting it since it seemed possible to foul a halyard. I assume the next higher rivet is also loose and that's how it found its new position. The mast is much quieter and we can finish the season this way, but it will require dropping the mast to properly repair- next winter. Good time to paint the mast, change the sheaves, replace the wiring and the VHF antenna, anchor light, steaming light .....
Well I finally got around to this project. We are preparing for a trip to the Bahamas and the Caribbean and pulled the boat apart to inspect the rig. The job was much easier than I expected. After placing the mast on saw horses with the leading edge up, I looked up the mast from the base and found the the conduit was only attached at the bottom, at the steaming light and the top! The attachment points are about every ten feet up the mast. To repair, I drilled out the rivets at the spinnaker halyard entry and exit plates and also the other failed attachment points. I fashioned a tool for pulling the conduit against the mast from a welding rod with 1.5" of one end bent at 90 deg. I also had to knock the coating off the welding rod to get it to fit through the 3/16" rivet holes. I simply inserted the welding rod bent end through the rivet hole near the center line of the mast. I then oriented the bend to point either up or down the mast and then lowered the bend to the back side of the mast. I then turned the welding rod 90 deg and started to fish for the conduit. Once I had the conduit, I pulled the conduit to the leading edge of the mast and held it there tight while I drilled a new 3/16" hole into the conduit. I then inserted the rivet through the hole in the mast and into the conduit and tightened the rivet. I then added additional attachment points between the existing ones to give additional support. This now works out to an attachment point every 5 feet or so up the mast. The hole job took 30 minuets! Now I feel that I could do the job from a bowsons chair on a standing mast. I am looking to forward to quieter nights at anchor without hearing the conduit slap the inside of the mast!
Ok old topic, but new problem to me. Last year at night when rolling at the dock got the dreaded banging from the mast. Had the mast pulled last fall to repair the mast step and had some time so decided to rewire the mast and switch to led lighting. Well found the bottom of the wire run loose in the mast but still attached further up. Did a search her and found lots of ideas on how to
re-rivet but came up with a different approach. Boat manufacturers join the top to the hull by glueing. So got a small tube of the devils glue 3m 5200 put a dab where the wire run goes and wedged in place with a wooden wedge. then went to the top and removed the mast head. Placed a small dab of 5200 between the wire chase and the mast so to keep the chase from moving and pulling out the rivets. Finally removed the steaming light and applied some 5200 between the chase and mast at the center point. Hoping all the horror stories are true and 5200 is permanent so this may work. Mast was left for a week without moving so it could setup. Launched boat, stepped mast and no noise so far.