Ericson 35-3 Cockpit Drain Hardware - Replacement screen available?

MarineCityBrian

Apprentice Tinkerer
I've got an E35-3 which has 4 cockpit drains (2 go directly to a seacock/thru-hull located just aft in the overhang beneath the transom, and 2 go to a seacock/thru-hull beneath the sink). Ever since I've owned the boat one of the drain screens has been missing/broken, and I was wondering if anyone has been able to secure a suitable replacement?
Here's a photo:
Cockpit Drain - Intact.jpg

I've never really found anything that exact diameter. All standard commercial drains seem to be a fair bit larger.

Thanks in advance for the help, and happy sailing! :egrin:
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
A quick on-line search turns up this shape of drain @ 3 1/4" diameter.
Exactly what diameter are yours?
 

Christian Williams

E381 - Los Angeles
Moderator
Blogs Author
Cockpit Drain Covers by Any Other Name...

Mine were worn out after 32 years. Dented, scratched, worn by a thousand days of Topsiders grinding potato chips into them.

But I couldn't find replacements for Perko cockpit grates anywhere on line.

That's because they're called "Perko Round Locker Vent Grilles." Exact replacements. Were they always called that? Who knows. Shiny news ones are a ten minute job that perks up the cockpit floor considerably.


 

MarineCityBrian

Apprentice Tinkerer
A quick on-line search turns up this shape of drain @ 3 1/4" diameter.
Exactly what diameter are yours?
I'll measure tonight. I'm not sure, but I'm pretty sure they aren't that big (They're < 3.25" in diameter).

Sea-Dog appears to make a similar one in both a 3.25" and 2.5" diameter, but there are only 6 slots as opposed to the 7 on my existing ones (I SWEAR a while back I had done an exhaustive search on this and came-up empty...of course NOW once I start searching I start getting leads.....but hey - maybe I can help others :) ).

From Sea-Dog's Web Site:
Sea-Dog Drain Cover Part Numbers and Sizes.JPG
Sea-Dog Drain Cover Drawing.JPGSea-Dog Drain Cover Picture - 6 Slots.JPG

I'll measure tonight to see if either of those dimensions jive with what I've got, and go from there. If they're a match, maybe I'll just order 2 and have a spare for the old ones. I'll keep everyone posted.
 

MarineCityBrian

Apprentice Tinkerer
Cockpit Drain Covers by Any Other Name...

Mine were worn out after 32 years. Dented, scratched, worn by a thousand days of Topsiders grinding potato chips into them.

But I couldn't find replacements for Perko cockpit grates anywhere on line.

That's because they're called "Perko Round Locker Vent Grilles." Exact replacements. Were they always called that? Who knows. Shiny news ones are a ten minute job that perks up the cockpit floor considerably.


Thank you Christian!!!! Of course, a completely different name....
I will search the interwebs directly!

Any idea which size was appropriate? I could not tell from your picture. They appear to be available in the same sizes as the Sea-Dog unit above (2.5" and 3.25").
https://www.perko.com/catalog/ventilators/360/locker_ventilator/
 
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MarineCityBrian

Apprentice Tinkerer
Perko thrifting throughout the years...

Also, amusingly, it's interesting to see the cost savings Perko presumably made on these parts throughout the years:
We start off with my early 80s example, with 7 slots, then move to the right with Christian's later 80s and more recent example with 6 slots, and finally the most recent example on Perko's web site with only 5 slots:
Perko Drain Cover Picture - 7 Slots.JPGPerko Drain Cover Picture - 6 Slots.JPGPerko Drain Cover Picture - 5 Slots.JPG
__________7 Slots_________________________6 Slots__________________________ 5 Slots___________

At the least I'd hope the material left between each slot would get thicker, making them less prone to failure (that's what happened to mine - the material between the slots cracked and it became sharp/dangerous so I removed it).

Again - will measure tonight and tell all the diameter.
I'm leaning toward the Sea-Dog stainless Steel version since they're both cheaper and should be stronger than the chrome plated brass...(and come in identical sizes)...
 

markvone

Sustaining Member
Brian,

Start with the Perkos. I got the Seadogs and the size is perfect but the mounting hole diameter is slightly smaller (1/8 - 1/4"). I had to fill and re-drill. The old holes are hidden under the covers. The Seadog quality is the same as the Perkos. HOWEVER, some may have the Seadogs per posts #8 and #21 in the link below.

http://www.ericsonyachts.org/infoexchange/showthread.php?15752-Replacing-Cockpit-Drain-(Scupper)-Cover

Seadog 3.25" cover bolt circle (dimension B in post 4) = 2.75"
Perko 3.25" cover bolt circle = ____ CAN SOMEONE MEASURE? (Est 2.875 - 3")

I also had one in the shower.

Another thing to consider: The cover slots reduce the the cross section area and increase drain time.

Mark
 
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debonAir

Member III
I got the stainless ones last year. They *almost* fit, had to drill out one or two holes to get the screws flush. Unfortunately, even with the wider metal, fewer slots they still bend if you step on them, After-all, a locker vent isn't going to be stepped on is it? I'd rather have a slightly thicker disc with more/smaller slots. Maybe I can make a batch with the new laser cutter at work.
 

MarineCityBrian

Apprentice Tinkerer
I would happily buy some from you if you do!
I was hoping the Sea-Dog stainless would be better than the Perko brass, but perhaps not. Perko does make a stainless version, so if they don't measure to be exactly the same as the Sea-Dog vents (which actually have the measurement for the bolt circle) then I have that option as well.
But let me know if you are going to do any laser cut ones. I'd happily whip up the CAD for them and could send it in whatever format you need.
 

debonAir

Member III
I'll ask the shop guys next week if they can cut stainless thick enough. I am guessing the vent covers I got are about 1/32 or so thick but 1/16 would be nicer, I'd also use 316 instead of 304 as well. The laser goes through 1/2 inch acrylic like butter and leaves a polished edge. I'm making a new cover for my engine control panel as well once I get that in CAD. If you have the Universal panel with the clear (or rather clear when new) cover that has cutouts on the bottom for glow/start on the left and key on the right, I will at least make one of those for you in exchange for the CAD files (scuppers and controls cover). DXF is fine. Also, if you have a drain cover out, measure the thickness and we'll maybe double it, and make more slots like the original ones.

McMaster sells 2'x2' of 0.06 polished 316 sheet for $155 which would be enough to make 49 scupper strainers I think (24" / 3.25" = 7, so 7x7 = 49) so that's about $4 per cover (shipping + bribing my coworkers). There's more waste if I use a smaller 1x1 sheet. I'll know on Monday if its possible, and if so, I'll post back here, then plz send the DXF files and I can crank some out. I know for sure I can do acrylic up to 1/2 inch at least.
 

MarineCityBrian

Apprentice Tinkerer
SWEET. I'll crank out a couple options for you to choose from this weekend and measure the existing thickness (tomorrow morning - never made it to the boat tonight). Agreed it could be at least double the thickness. Also, if brushed out unpolished is cheaper that would be an option, but polished would be awfully cool. In my experience laser cutting leaves small burn marks on metals. There's special laser cut stock with peel tape on it to minimize that. Plus if polished after cutting it would both remove any burn marks and soften the sharp edges left by the laser cutter. Possible with a Dremel and polish attachment.
I'll shoot you some pics of the CAD this weekend or Monday once I measure up the parts. Any min radii for your laser cutter? Typically they can create a sharp internal corner, so design options open up but that doesn't look as nice to me.
 

MarineCityBrian

Apprentice Tinkerer
Cockpit drain cover plate/Scupper dimensions!

Ok, the measurements are in:
Outside diameter: 3.255" (so the 3.25" diameter units are correct and I was completely mistaken in my understanding their diameter - Loren, you were spot-on).
IMG_20190503_085633.jpg

Bolt circle diameter: 2.875"
IMG_20190503_085711.jpg
The above at 2-7/8" means that the Sea Dog units will have to small a bolt circle since their part is listed at 2-3/4" for the bolt circle; 1/8" too small.

The thickness is, as was estimated, around 1/32":
IMG_20190503_085754.jpg

Next, I ask this question: If we're designing our own custom part, do we want to only have slots over where there's an open hole, to avoid exposing part of the drain as the current grates do?:
1556889954-picsay.jpg

If you want I can make the slots only occur within the red dotted circle. Or maybe a bit bigger and make them extend to the edge of the chamfer.
 
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Christian Williams

E381 - Los Angeles
Moderator
Blogs Author
First, I would certainly not reduce the slotted area, which would reduce flow and clog faster.

Also, who needs a custom replacement for a $10 item if you have the 3 1/4 deck molding for the covers?

If the holes don't match, drill new ones. The holes are covered by the plate anyhow.
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Slots vs restriction

Overall "thru put" is important for a cockpit drain.
These slotted covers devices are just there to catch and hold onto small items that would either be lost out the drain hoses or worse yet jam in the 90 degree elbow directly under the drain entry in amy of our boats.

While I cannot prove it off hand, I believe that the slots extending out to the outside of the top of the cast Marelon "funnel" help make up for the reduction in total flow that they impose on the ability of the fitting ID to pass liquid.

I have only been on one delivery where the boat was pooped and the wave crest stopped at the closed companionway door, I would not want that "ability to drain" compromised more than needed. (!)

Something to consider.....
 

mfield

Member III
Also, who needs a custom replacement for a $10 item if you have the 3 1/4 deck molding for the covers?
I don't think you are entering into the full spirit of this Christian. In the words of S.R. Hadden, why build one when you can build two at twice the price.

Damn the torpedoes and make them out of gold plated titanium.
 
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MarineCityBrian

Apprentice Tinkerer
Why would I create something better than I could buy? Because I CAN. :newwink:
That said, while debonAir was working out the details of the laser cutter, I went ahead and ordered a pair of Perko stainless units to at least replace the broken one I had (replacing a pair since they no longer carry the 7-slot units, and I need to keep the boat's feng-shui in order) and discovered that PERKO changed their design! The bolt circle is smaller than mine, so either Perko changed their design or Ericson got these earlier units from a different source.
I'm doing my best to line up each vent to show the difference in bolt circle (original unit above, new below):
IMG_20190517_101602.jpg

So I guess for now I'll mount these at a 45 and make new bolt holes. My Starboard side drain grates were always crooked anyway. The port ones are nice and pointing straight fore and aft. The Starboard; not so much.:newwink:
 
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Christian Williams

E381 - Los Angeles
Moderator
Blogs Author
I hate to keep making things easy, but somebody's got to do it.:)

Do some holes match? Fill the misaligned holes with epoxy and redrill them. Or drill all new holes, and if no epoxy is handy, stick caulk in the old holes. Total Work time 5 minutes each.

All grille slots must appear to the eye to be parallel. Otherwise they will draw a lightning bolt from Zeus right straight into your cockpit, and that is a proven fact.
 
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