Mast track bolts stripped...best fix?

[mrybas]

Cut the pulled out section of track and installed helicoils and reinstalled the track.  Then I went up the mast and found a few more stripped screws. With the random stripped screws, I was able to install the helicoil without removing the track (had to mod the helicoil installer Dodad to fit inside the track bolt hole.

Whats the deal with ‘glue on’ tracks?

 

[longy]

They have wide mounting flanges, about 3/4" each side to get surface area for the glue bond. Installed with HYSOL or equivalent epoxy. They still have fasteners at high load areas, usually rivets thru the side flanges. Antal has several flavors, but you have to use their cars (of course!)

 

[CaptainAhab]

Somebody must have done a shite job tapping those original holes. It’s not like anything is moving around. The typical problem is the mast corrodes and you can’t get them out. I guess it’s possible down low. Some guy might get a bit aggressive with the out haul when putting in a reef. Put it on a winch and pull that fucker tight.

 

[mrybas]

Somebody must have done a shite job tapping those original holes. It’s not like anything is moving around. The typical problem is the mast corrodes and you can’t get them out. I guess it’s possible down low. Some guy might get a bit aggressive with the out haul when putting in a reef. Put it on a winch and pull that fucker tight.

I think the issue is likely from dissimilar metal corrosion of the aluminum tapped track inside the mast.   2 years ago I attempted to remove the track to paint the mast.  I got 90% of the fasteners out, but the rest would not come free while trying all the tricks in the book. I used new fasteners when reinstalling, but probably should have helicoiled each one.

Ill just have to keep an eye on it for now and maybe replace the track next summer with glue and screw.

The reef was put in by hand (no winch), using the topping lift to get the clew close to the boom.

 

[slug zitski]

Cut the pulled out section of track and installed helicoils and reinstalled the track.  Then I went up the mast and found a few more stripped screws. With the random stripped screws, I was able to install the helicoil without removing the track (had to mod the helicoil installer Dodad to fit inside the track bolt hole.

Whats the deal with ‘glue on’ tracks?

View attachment 397856

On a carbon mast the epoxy isolates the aluminum track from the carbon spar 

the epoxy bed also provides greater surface track or hardware surface contact area and avoids point loading at the fasteners 

It’s a pro detail , replicate 

 

[CaptainAhab]

On a carbon mast the epoxy isolates the aluminum track from the carbon spar 

the epoxy bed also provides greater surface track or hardware surface contact area and avoids point loading at the fasteners 

It’s a pro detail , replicate 

The pro detail is to layup (1) 200g(6oz) layer of glass between the track and the carbon spar. You then bond the track down with the appropriate Plexus adhesive. Using masking tape until it cures. 

 

[mrybas]

The mast is carbon wrapped with a sacrificial layer of 4 or 6 oz glass on the exterior.

The mast track is tapped into a 3/8” thick aluminum bar stock glassed into the inside of the mast. I think 10 years of SS fasteners in the AL are compromised by corrosion.  No way around it.....unless tefgeling you’re SS on AL fittings on a yearly basis, the AL is going to corrode. 

 

[slug zitski]

The mast is carbon wrapped with a sacrificial layer of 4 or 6 oz glass on the exterior.

The mast track is tapped into a 3/8” thick aluminum bar stock glassed into the inside of the mast. I think 10 years of SS fasteners in the AL are compromised by corrosion.  No way around it.....unless tefgeling you’re SS on AL fittings on a yearly basis, the AL is going to corrode. 

On a mast track the lubricity of tefgel will cause the fasteners to back out when load cycled 

you must use a thread locker

many  thread locker products around

if you prefer to stay in the Tefgel product range use Tuffgel

 https://www.tefgel.com/contain.php?param=tuffgel_infor

it’s  a 1.7 Nm break strength thread locker 

 

[IStream]

On a mast track the lubricity of tefgel will cause the fasteners to back out when load cycled 

you must use a thread locker

many  thread locker products around

if you prefer to stay in the Tefgel product range use Tuffgel

 https://www.tefgel.com/contain.php?param=tuffgel_infor

it’s  a 1.7 Nm break strength thread locker 

No it will not and no you don't. 

As long as there is sufficient clamping force, there will be no relative movement between the fastener and the mast and no loosening of the fastener. Dissimilar metal corrosion that leads to thread degradation leads to working of the track, which leads to failure of additional fasteners. 

There's no harm done from using an appropriate thread locker that also provides dissimilar metal corrosion protection but I'd sooner take plain old Tefgel on stainless fasteners in aluminum over a thread locker that doesn't provide corrosion protection.

 

[Raz'r]

No it will not and no you don't. 

As long as there is sufficient clamping force, there will be no relative movement between the fastener and the mast and no loosening of the fastener. Dissimilar metal corrosion that leads to thread degradation leads to working of the track, which leads to failure of additional fasteners. 

There's no harm done from using an appropriate thread locker that also provides dissimilar metal corrosion protection but I'd sooner take plain old Tefgel on stainless fasteners in aluminum over a thread locker that doesn't provide corrosion protection.

In this case, the helicoils are already installed. The stainless screws won’t react with the stainless helicoils. The helicoils might react with the aluminum but that’s too late. Yes, thread lock could be used. But I’d use the light stuff, blue IIRC not the hard core red stuff.

 

[IStream]

You'll likely get at least as long out of the helicoils as you got out of the original fasteners. Forget it and go sailing...

 

[mrybas]

You'll likely get at least as long out of the helicoils as you got out of the original fasteners. Forget it and go sailing...

Leaving (OCMD)  tomorrow morning to go around Hatteras and spend a couple days at Cape Lookout.  
I think the track should be good for now, with the loose screw holes now helicoiled.  It’s something I’ll keep an eye on and consider replacing this track with a glue on next summer.

Out of curiosity what does 180ish .25”x1.25” screws weigh?

 

[IStream]

Roughly 40oz or 2.5lbs.

 

[SASSAFRASS]

Helicoils are common in OEM industrial applications mounting SS to aluminum.  As long as the aluminum is still ok I would go for it. Alot of the kits come with drill bit tap and insertion tool.  There is a specific loctite that is reccomended for inserts, I can't remember which one but Google is your friend.

It's a stronger connection than just drilling and tapping, the fastener compresses the coil making a better fit.

If it's a total shitshow you could get a couple new splice links and a short section of track.  Pull the existing with bad bolts and cut off some to move the bolt holes to new location add small piece at the bottom.

 

[CaptainAhab]

On a mast track the lubricity of tefgel will cause the fasteners to back out when load cycled 

you must use a thread locker

many  thread locker products around

if you prefer to stay in the Tefgel product range use Tuffgel

 https://www.tefgel.com/contain.php?param=tuffgel_infor

it’s  a 1.7 Nm break strength thread locker 

No

Does anyone remember what was used before all of goops we use now? 
 

Typical off the shelf lithium grease will prevent aluminium from corroding for decades. We refurbed the 1980 IOR custom in 1992. Zero issues taking out hundreds of 1/4-20’s. 
 

The world would fall apart if It was true that vibration loosened greased fasteners. You need to use the correct grease and know the appropriate torque. 

 

[longy]

For most uses, just keeping salt from the joint will prevent corrosion. A good silicone seal in the color of your choice will work fine, and have just a small bit of adhesion