I have been noticing the slow spread of corrosion at the base of my mast. A rigger told me I had water inside and that I should drill holes to drain out the water which I did over a year ago. I am planning to step the mast this summer and get a closer look. At that time I will seal any leaks on the mast. I will order a new mast "boot" from Catalina. But I'm wondering if anyone else has dealt with this problem and what you did? Will I need to grind off the corrosion at the bottom to even it out?? I attach a picture which also shows that the mast seems to have "sunk" into the deck more forward. Any experience on this issue would be appreciated. Thanks, Jim
mast base corrosion
- Thread starter sunwindsea
- Start date
im not familier with the boat, but it appears to be a deck stepped mast.... so there should be a mounting plate under it....
in my opinion, the plate sinking into the deck is more of a concern than is the amount of corrosion you have gong on.
I would bet the rigger is correct and there is quite a bit of water in the mast... this would easily explain the sinking mount.... water intrusion thru the retaining bolts and rotting the core.
that will need to be fixed as soon as possible to prevent further damage....
the mast should have had drain holes/slots in it before it was stepped originally, but sometimes people think the water will drain out thru the cracks.
this is true for a new assembly that has not has time to accumulate debris and corrosion, but after a few years the accumulation can effectively dam the escape route for the water and leave you with a problem that will eventually show up... and you have the photo to prove it.
unless it is a keel stepped mast, DONT use a mast boot.... for a deck stepped mast you want the area to have open drainage and ventilation.... inside and out.
a certain amount of water IS going to find its way into the mast, there is no getting around that... so the only fix is good drainage..... ventilation will be a natural occurrence if there is a hole at the bottom for drainage and a way for air to escape at the top.
get the mast off the base, clean away the debris and sediments that have dammed the drainage, install a more permanent and active rather than passive drainage route, and deal with the corrosion in what ever manner you choose, BUT ONLY AFTER reading about corrosion on aluminum..... because sometimes is better to just allow it to dry and leave it alone rather than grinding off the protective layer that it has created for itself.
but letting water set against it (inside) as it is now, is bad, bad, bad....
in my opinion, the plate sinking into the deck is more of a concern than is the amount of corrosion you have gong on.
I would bet the rigger is correct and there is quite a bit of water in the mast... this would easily explain the sinking mount.... water intrusion thru the retaining bolts and rotting the core.
that will need to be fixed as soon as possible to prevent further damage....
the mast should have had drain holes/slots in it before it was stepped originally, but sometimes people think the water will drain out thru the cracks.
this is true for a new assembly that has not has time to accumulate debris and corrosion, but after a few years the accumulation can effectively dam the escape route for the water and leave you with a problem that will eventually show up... and you have the photo to prove it.
unless it is a keel stepped mast, DONT use a mast boot.... for a deck stepped mast you want the area to have open drainage and ventilation.... inside and out.
a certain amount of water IS going to find its way into the mast, there is no getting around that... so the only fix is good drainage..... ventilation will be a natural occurrence if there is a hole at the bottom for drainage and a way for air to escape at the top.
get the mast off the base, clean away the debris and sediments that have dammed the drainage, install a more permanent and active rather than passive drainage route, and deal with the corrosion in what ever manner you choose, BUT ONLY AFTER reading about corrosion on aluminum..... because sometimes is better to just allow it to dry and leave it alone rather than grinding off the protective layer that it has created for itself.
but letting water set against it (inside) as it is now, is bad, bad, bad....
Center,
There have been numerous threads dealing with your issues. If you have had standing water at your base, I'll guarantee you have water in you coring also. You have noticed sagging & this is because your balsa core/plywood(?) is wet & soggy. This is due to bad design, installation techniques, no drainage & an open top masthead crane.
When you step your stick, start a new thread & I will tell you how I closed off the top, fixed the sag & re-did the wiring to seal off any water intrusion. I also have pics & sketches for my fix.
Alot of the guys will also have additional tips for you to fix your problem. So, you will be in good hands partner.
CR
There have been numerous threads dealing with your issues. If you have had standing water at your base, I'll guarantee you have water in you coring also. You have noticed sagging & this is because your balsa core/plywood(?) is wet & soggy. This is due to bad design, installation techniques, no drainage & an open top masthead crane.
When you step your stick, start a new thread & I will tell you how I closed off the top, fixed the sag & re-did the wiring to seal off any water intrusion. I also have pics & sketches for my fix.
Alot of the guys will also have additional tips for you to fix your problem. So, you will be in good hands partner.
CR
Thanks, CR, this is what I was hoping for. I plan to do this in the summer in San Carlos, Sonora, Mx (I took the boat down there from CA last May). Are there any special tools or material I need to take with me when I go down?
Don't forget to check your compression block.
While your mast is stepped, check the compression block in the bilge. We didn't even think about it. Duh on us. We now have to figure out how to replace it without going thru the added expense of having to unstep the mast and retune the rigging. The top of our mast is still open and we have drainage holes in the bottom. We have a 1978 Catalina Hull # 959.
While your mast is stepped, check the compression block in the bilge. We didn't even think about it. Duh on us. We now have to figure out how to replace it without going thru the added expense of having to unstep the mast and retune the rigging. The top of our mast is still open and we have drainage holes in the bottom. We have a 1978 Catalina Hull # 959.
Wind,
I hate to say this pal but, your problem is NOT a quick fix. It has to be done RIGHT to be done ONCE.
You NEED to step the mast, You NEED to repair/replace the compression block, you probably NEED to dig out the deck & coring rot under the mast & if so, you NEED to reseal your wiring penetrations & base plate, you NEED to close off the masthead crane & allow for drainage at the base. So, I wouldn't worry about having to re-tune your rigging, that's the least of your problems.
This is a BIG BAD design flaw by Catalina as, there have been soo many threads on this. To save money, first find a good glass man. You will have to support the headliner before you fix the compression block. This is pretty simple but if you are unsure, I would not attempt this repair yourself.
The deck is another part that I assure you is probably rotted core also. The compression block became soaked because of water in the bilge & because the block was NOT sealed off. If you find deck rot, chances are the thru-deck penetrations will have to be PROPERLY re-done also.
I hate to sound like the bearer of bad news but, I went thru everything except the compression block. Will it cost money? Yes, for the boatyard picking-n-splashing & stepping. However, if you can do repair work at your slip, have the yard drop the stick & hold it for you. Take your boat to your dock for all the repair work. When done, take it back to the boatyard to mount the mast. I would look for GOOD independents to do the work, not the yard if money is an issue.
I may have some good news for you, as I made a close-off for the top of my mast & came up with some great fixes for keeping the base & electrical penetrations dry. I also did a mast venting based on cooling tower science to keep it dry. I also have pics of what I did that may help.
Having a boat is gonna cost you money, that's just the nature of the beast pal.
CR
I hate to say this pal but, your problem is NOT a quick fix. It has to be done RIGHT to be done ONCE.
You NEED to step the mast, You NEED to repair/replace the compression block, you probably NEED to dig out the deck & coring rot under the mast & if so, you NEED to reseal your wiring penetrations & base plate, you NEED to close off the masthead crane & allow for drainage at the base. So, I wouldn't worry about having to re-tune your rigging, that's the least of your problems.
This is a BIG BAD design flaw by Catalina as, there have been soo many threads on this. To save money, first find a good glass man. You will have to support the headliner before you fix the compression block. This is pretty simple but if you are unsure, I would not attempt this repair yourself.
The deck is another part that I assure you is probably rotted core also. The compression block became soaked because of water in the bilge & because the block was NOT sealed off. If you find deck rot, chances are the thru-deck penetrations will have to be PROPERLY re-done also.
I hate to sound like the bearer of bad news but, I went thru everything except the compression block. Will it cost money? Yes, for the boatyard picking-n-splashing & stepping. However, if you can do repair work at your slip, have the yard drop the stick & hold it for you. Take your boat to your dock for all the repair work. When done, take it back to the boatyard to mount the mast. I would look for GOOD independents to do the work, not the yard if money is an issue.
I may have some good news for you, as I made a close-off for the top of my mast & came up with some great fixes for keeping the base & electrical penetrations dry. I also did a mast venting based on cooling tower science to keep it dry. I also have pics of what I did that may help.
Having a boat is gonna cost you money, that's just the nature of the beast pal.
CR
CR is correct on all counts. The deck/ fiberglass is the hardest part. The glass work is not impossible but just tedious.
I recored my cockpit sole last summer, the experience sucked so discretion and a little cash outlay may be the way to go.
You will be surprised at the amount of bird droppings that will come out of your stick when pulled. I just had my old step recoated added a plate underneath. Neither were that expensive.
I recored my cockpit sole last summer, the experience sucked so discretion and a little cash outlay may be the way to go.
You will be surprised at the amount of bird droppings that will come out of your stick when pulled. I just had my old step recoated added a plate underneath. Neither were that expensive.
Attachments
Sun,
Asking what tools are needed, I get the feeling You have not done very much glass work/structural repair. And, that's OK, as we were all first-time timers at one point.
After checking to see what & where damage, then comes planning your project. You will first need to repair the compression block. For this repair, you will need to jack up the head liner to the height it's supposed to be. You can call Catalina in Calif. @ 818.884.7700, Ask for the Engineering Dept. to send you drawings showing dimensions.
Once the block is replaced/repaired, next is the deck. For this, & the block repair, I would advise getting a good local Glassman. The prices in Mexico should be affordable.
There are numerous threads covering these fixes, I would advise you to spend some time & go thru these threads. They will detail specific info on what others did. Copy & paste posts needed for referencing details of the fixes & how-to's.
Remember ,to first write your plan in the correct sequence. When you have this completed, this will help you in making a material list & tools needed.
It's important you remain patient, organized & focused. I always say, "Work smart, not hard." As you get further into this, us guys on SBO can help with advice.
About closing off the mast top, here's a look at whet I did. Later on, I can go over what I did at the mast step for sealing wiring, step plats & vent drying.
CR
Asking what tools are needed, I get the feeling You have not done very much glass work/structural repair. And, that's OK, as we were all first-time timers at one point.
After checking to see what & where damage, then comes planning your project. You will first need to repair the compression block. For this repair, you will need to jack up the head liner to the height it's supposed to be. You can call Catalina in Calif. @ 818.884.7700, Ask for the Engineering Dept. to send you drawings showing dimensions.
Once the block is replaced/repaired, next is the deck. For this, & the block repair, I would advise getting a good local Glassman. The prices in Mexico should be affordable.
There are numerous threads covering these fixes, I would advise you to spend some time & go thru these threads. They will detail specific info on what others did. Copy & paste posts needed for referencing details of the fixes & how-to's.
Remember ,to first write your plan in the correct sequence. When you have this completed, this will help you in making a material list & tools needed.
It's important you remain patient, organized & focused. I always say, "Work smart, not hard." As you get further into this, us guys on SBO can help with advice.
About closing off the mast top, here's a look at whet I did. Later on, I can go over what I did at the mast step for sealing wiring, step plats & vent drying.
CR
Attachments
CR,
As to closing off the top I am installing these this weekend when I put on my windex.
5 Feet of Fly-bye Narrow Spike 100% Stainless Steel! No Plastic Parts. https://www.amazon.com/dp/B0001IMMC0/ref=cm_sw_r_awd_sqcPub0Y576CF
I have already drilled and cut the strips to fit. 2 side by side cover the holes nicely. Is there a downside to spikes?
As to closing off the top I am installing these this weekend when I put on my windex.
5 Feet of Fly-bye Narrow Spike 100% Stainless Steel! No Plastic Parts. https://www.amazon.com/dp/B0001IMMC0/ref=cm_sw_r_awd_sqcPub0Y576CF
I have already drilled and cut the strips to fit. 2 side by side cover the holes nicely. Is there a downside to spikes?
Gar,
I looked at a bird repellant product at the time, similar to this but mine didn't work.
Thanks for the link, I'll check it out pal.
What you used, what was the width man?
My close-off was simple but Ospreys keep breaking off my antenna.....them damn rats with wings!!!
CR
I looked at a bird repellant product at the time, similar to this but mine didn't work.
Thanks for the link, I'll check it out pal.
What you used, what was the width man?
My close-off was simple but Ospreys keep breaking off my antenna.....them damn rats with wings!!!
CR