1801 Scupper tube replacement

[Legal Bill]

Your hardware problem is not unusual. My old hardware often breaks at the point where the cap or head of the screw meets the shaft. I think it is stress corrosion cracking, but I never researched it. I have run into this on both vertical and horizontal installations. I now have a $300+ inventory of 316 hardware and try to use all new every time I rebed something.

 

[pelagic2530]

I did pilot and predrill. The hardware was the original ones. Has no issues with the other 3 scuppers.

I see. It's possible that the original hardware corroded where the sealant from the original installation deprived the stainless of oxygen. In an oxygen-depleted environment, the stainless treatment of the steel becomes ineffective, which can lead to wasting and/or weakening of the fastener if it's subsequently exposed to water. It's this reason that bronze is recommended for most hardware for use below the waterline.

Out of curiosity- did you happen to keep the hardware separate for each scupper as you removed them? Looking at your pictures, it appears that of the four scuppers, the bottom screw on each may be at/near the waterline, and those would be the ones most susceptible to this type of damage. That leads to four potentially damaged screws... which is the number you had break. Chance in a million that they'd all end up on the same scupper, but still...

I try to make it a habit of not re-using hardware, especially stuff that I know has been exposed or was used under/near the waterline. It's painful, but if a couple bucks per project keeps me from having broken screws, I think it's probably worth it.

 

[pelagic2530]

Your hardware problem is not unusual. My old hardware often breaks at the point where the cap or head of the screw meets the shaft. I think it is stress corrosion cracking, but I never researched it. I have run into this on both vertical and horizontal installations. I now have a $300+ inventory of 316 hardware and try to use all new every time I rebed something.

Legal Bill, I have a very similar inventory of hardware. I sourced mine in the boxed kits from Stainless Steel Marine Fasteners, Fittings, & Bolts Supply. Overall prices aren't terrible, and having them on hand has probably saved me hours of cumulative time driving to and from hardware stores over hardware that was just a HAIR too long/short/wide/etc. Plus, they never go bad in the box!

 

[tomc585]

All good points and .....lesson learned (the hard way). Tomorrow I'll be shopping for the hollow core bit to try to find one local. To many questionable reviews with the ones available online braking. I'd like to wrap this project up and drop her in the water where she belongs.

 

[tomc585]

Hollow screw extracters arrived today. Bought 3 for good measure. Good theory just difficult to exicute. They are thin walled and very brittle. You need to be perfectly centered and squared with the broken screw. If you hit it...it breaks without warning. If the screw was in on any angle you would need to follow that angle. I used a piece of 3/4" wood stock clamped to the transom with a 1/4" hole for use as a guide to keep it from walking, this worked for 2 holes then I had to make a new guide hole because it started opening up and was walking a little bit. So I'm 5 for 5 and only broke both sides of 1 bit. First break was in the first 20 seconds on one screw that was too large in diameter for the bit and I caught it. The bits I bought are 1/4" (3/16" ID) so little room for error. I should have bought the 5/16" but I was trying to keep the new holes as small as possible. Boy am I glad thats over.

 

[pelagic2530]

Glad you were able to get them out. How long were the screws you used? Those look awful long for something like scuppers.

 

[tomc585]

They were OEM and 1" at the most. The pieces I retrived are about 5/8" and shorter and were flush with the gelcoat barely making it throught the fiberglass.
Need to dress up the epoxy I set last night.

 

[tomc585]

Update: Happy to say that I am very pleased with the recommendation from Pelagic2530 on the T-H MaxFlo ball scuppers. The splash well has never been dryer and the blues dont seem to mind the noise. 4 drains seems like over kill but I've been in some snotty stuff and when the water comes over the bow its not on board very long.