This article showcases the port replacement I did on our 1979 CS-36T. After much research I chose New Found Metals portlights. As always double click any image to see a larger and higher resolution version.
Choosing to install new portlights is a complicated decision. There are many companies out there building poor products that sell for big money and others building beautiful products that sell for a reasonable amount. My decision involved much research and investigation into the minute details of portlight construction. Many of the larger, well known, companies did not stack up when I began to dig into the small details so I chose New Found Metals as my portlight supplier.
This project is not for the boater who barely knows the difference between a Phillips head and a slotted head screw driver and is about a 5-6 on the 1 to 10 complexity scale. The task is straight forward and does not require "artist" like skills akin to blending and color matching gelcoat but it is a long and time consuming task.
Our boat has 8 ports and I figure this project took me a little over 45 hours of time. Hopefully this article will save you some time and you can learn from my mistakes and time saving tips. I figured each port would take about two hours but I was a little off.
I do hope this article helps someone considering new ports or who needs some guidance installing NFM portlights.
As always click on any photo and it will get bigger and offer more resolution. This article is quite LONG and totals four pages and more than 40 photos so don't forget to click "next page" when you get to the bottom.
MAY-2006
Phase 1 - Measuring Exterior Offset
Before you can even order your New Found Metals ports (NFM from here on) you need to know the thickness of your cabin sides. All NFM bolts are metric therefore I used my calipers in metric mode to determine an accurate bolt size.
You need to measure the exterior off set from the widest point of the old port to the cabin sides. To do this I used my adjustable carpenters combination square as in the picture. Once I had the measurement I locked the set screw.
MAY-2006
Reading Exterior Offset
Before moving on to the next measurement you need to write down your measurement or transpose it, as I did, to my calipers. The exterior offset reading was rounded up to 13.5mm.
The picture shows the accuracy a little bit off but it was hard to hold the caliper and square in one hand and the large Nikon DSLR in the other and keep it perfectly in place..
MAY-2006
Measuring Interior Offset
You also need to measure the interior offset. I did not want the gasket compressing under the square, and throwing my reading off, so I removed the gasket/seal on the Beckson ports to get a more accurate reading.
Note the gasket grove or slot on the port and the staining & grime from leaking. I had totally cleaned each of these slots or groves last spring and installed new gaskets, yet a few of these ports continued to leak. I guess plastic, in the marine environment, has a useful lifespan that had been surpassed..
MAY-2006
Reading Interior Offset
Do the same for the interior offset and write this number down. I rounded this up to 9mm.
MAY-2006
Measuring Port Total Thickness - Interior View
Now you need the ports total thickness as measured from the widest/thickest point on the interior of the frame to the widest/thickest point on the exterior. I rounded this number to 34mm.
The math is now very easy. Simply add the interior and exterior offset numbers together. It looks like this:
13.5mm + 9mm = 22.5mm.
Next, simply subtract the offset totals of 22.5mm from 34mm. It looks like this:
34mm - 22.5mm = 12.5mm.
The cabin sides of our boat were roughly 12.5mm thick which translates to 0.4921 or roughly 1/2".
This is the number you call NFM with so they can calculate your total bolt length for you. It is very important to know this number before placing your order as it will save lots of time later. Physically cutting eight + bolts per port is a tedious and time consuming task! Trust me..
On a cabin with solid fiberglass sides, as my boat is, you will also want to order interior teak spacers or the spigot will protrude further than necessary. More on this bellow..
MAY-2006
Measuring Port Total Thickness - Exterior View
You can see my calipers clamped to the widest point of the port in this exterior view.
MAY-2006
Trim Ring Thread Depth
I had this metric bolt kicking around and decided to illustrated why proper cabin thickness is a must. I inserted the bolt until it bottomed out then wrapped some Teflon tape around it and backed it out.
MAY-2006
Actual Depth
My caliper shows this hole at 7/16 but most of the others were 5/16 just as NFM says they are. Plan on a quarter inch of room, as a safety margin, and you'll be fine. This bolt depth obstacle is kind of a tedious but it prevents any screws visible on the out side of the portlights which could leak and it looks better.
MAY-2006
The Old Ports
As you can see these ports were not very attractive. To make matters worse the barrel nuts used to hold the trim rings on were chrome plated brass not stainless. I'm guessing stainless barrel nuts were not available back in 1979..
MAY-2006
Phase 2 - Removing The Old Ports
Lucky for me, the Beckson ports had been installed with butyl tape and a double sided foam weather stripping, and not one of the high tenacity polyurethane sealants like 3M 5200. All I needed was to pry the trim rings off the cabin sides and then apply a constant pressure to slowly stretch the butyl and remove the ports.
I used my heavy duty putty knife, that I have properly dulled, so I don't scratch the cabin sides.
If your ports were installed with 3M 5200 please be very, very careful removing them. The tensile strength of 5200 is 700 PSI and the fiberglass to gelcoat bond is roughly 400-500 PSI. What this means is that if you try to force the ports off the boat you can literally tear the gelcoat clean off the substrate. In my opinion, garnered over many years of removing this stuff, 3M 5200 has no place on a boat! Use 5200 at your own risk and remember NOTHING ON A BOAT IS EVER PERMANENT NOT EVEN A KEEL.
If you're at a loss with 5200 try products such as De-Bond to soften it. Sometimes heat will help to soften the 5200 but do be careful using heat guns. They can burn the gelcoat if not used carefully, at safe temps, and kept moving at all times.
MAY-2006
30 Year Old Butyl Tape - Still Very Flexible
For those who doubt the utility of butyl tape on boats, and who chose to use polyurethane products such as 5200, for installing ports, this photos speaks for itself.
As you can see, after nearly 30 years the butyl tape still had elongation before break of more than 2000% at a minimum. The butyl tape on all 8 ports never failed and my leaks were from Beckson port gaskets, even after replacements had been installed.
I also had a couple of fasteners, that went through the foam weather stripping gasket used on the trim ring (not butyl), also leak.
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MAY-2006
Clean Up The Surface
To clean up the residue I used my "boat chisel". My boat chisel has been sharpened to minimize scratching the surface. If you're not skilled in the use of a chisel or dulling or sharpening them the right amount, find another way of removing the vast amount of sealant or you could scratch your hull.
Once I had the majority of the surface clean I used Paint Thinner (it works well on butyl) and then Acetone, with chemical resistant gloves on, to do a final cleaning.
MAY-2006
Phase 3 (optional) - Cabin Side Compounding
While you have your ports out you may want to take the time to compound and polish the cabin sides. It's much easier without the ports getting in the way. I simply used Gorilla tape on the inside of the cabin to seal off the port openings then buffed away.
For the compounding phase I used a Makita 9227C buffer at 600-1500 RPM, Presta Ultra Cutting Creme compound and a 3M compounding grade pad part #05711.
For the polishing phase I used a Makita 9227C buffer at 600-1500 RPM and Presta Chroma 1500 polish with the blue wool Presta polishing grade pad.
MAY-2006
Taping Off The Inside
Here's a shot of the Gorilla Tape (duct tape) I used when compounding the cabin sides to prevent a mess inside the boat..
MAY-2006
Polishing The Cabin Sides Before & After
There's no doubt it's well worth it to take this extra step!
MAY-2006
Temporary Duct Tape To Cover The Openings
Here's another tip, this one for keeping your boat dry while the work is in process.
I chose to remove all the old ports then prep, cut, drill, chamfer and bore the openings all at the same time but needed a way to keep the boat dry as I was going through the installation process.
I have been using Gorilla Tape from the makers of Gorilla Glue and it is far and away the finest duct tape made. It's thick, does not leave much if any residue, and sticks tenaciously to just about anything.
To seal the port openings, until you can install the ports, start at the bottom of the port opening and work your way up like clapboards on a house overlapping each seam by about 1/2". If you worked your way down water will get in but if you tape from the bottom up the seams over lap so they don't drain into one another.
Even though my boat is covered I didn't want to take any chances, and yes this stuff will keep rain out!
MAY-2006
Why I NeededTo Replace My Ports
After 29 years the plastic had become quite brittle and many of my hinges looked like this or worse. I won't have to worry about the NFM cast stainless steel ports degrading or becoming brittle.. ever!
MAY-2006
Why I NeededTo Replace My Ports 2
As I said some were worse! This hinge literally fell apart after I removed the port. In defense of Beckson these plastic ports lasted almost 29 years but should have probably been replaced about ten years ago.
It should be noted that these Beckson ports were no longer safe for any sort off shore sailing. One big wave surely could have broken them, in the brittle state they were in, and allowed your boat to take on green water..
MAY-2006
Phase 4 - NFM 4X14 Template With Drill Guides
This is the actual template from NFM. They charge you for it but when you return it they will credit back your $90.00.
Installing these ports without one is just being penny wise and pound foolish, so don't do it.
As you can see from the photo these templates are very heavily made and have built in drill guides which make drilling straight holes, through angled cabin sides, very easy. I have included a pen in the photo to show how robust these things are.
Please plan ahead when buying from NFM as they often run out of templates. I waited almost 5 months to get one and came very close to not buying NFM ports because of this!
Oh, and if you do use a template, please send it back when you're done so others don't have to wait eons to get one...
MAY-2006
Template / Guide & Hull
For the next step I needed to cut the openings for the NFM ports slightly bigger than the Beckson's had been and also accommodate for the spigot. I used the NFM Template (shown in the previous photo) which, as I said, is a must have item for this job.
To cut the openings I chose to use the NFM template as my router guide and use my Ryobi laminate trimmer with a bearing guided flush cut bit. Using a jig saw, hand saw or sanding drums just seemed like an awful lot of work!
This photo shows the template clamped to the inside of the cabin and a partial routed edge. Make sure you clamp tightly!
MAY-2006
Cutting The New Port Openings
In order to get the laminate trimmer around the entire opening you'll need to move the clamps as you go. Just cut a section them move the clamps. I was able to cut an entire port with only three clamp moves and the template stayed put.
As evidenced by the photo, using the flush cut bit and the NFM template as a guide, leaves a perfect cut that looked better than the original factory openings..
MAY-2006
Vacuum Tip
I know this has nothing to do with NFM portlights but the Rigid 6 Gallon wet dry vacuum, from Home Depot, at $39.00 is a great investment for working on your boat! I actually got rid of my big shop vacuums and now have three of these 6 gallon models. One for the barn, one for the garage and one for the boat!! It's tiny, powerful and easy to lug up and down ladders.
I always ditch the hoses that come with shop vac's and visit a local vacuum shop for an adapter and about 20 feet of central vac hose. This makes using a cumbersome shop vac a pleasure. The home attachments are better too. The horse hair brush (pictured) is one of my favorites. Within 25 minutes I had totally cleaned my interior of all the routing dust with the horse hair brush and the central vacuum hose.
I love this combo, so I thought I'd share.
MAY-2006
My Ryobi Laminate Trimmer / Flush Cut Bit
Here's a close up of my laminate trimmer. The base of my standard Porter Cable router was just a bit large for cutting these port openings. Unless you have lots of flat cabin side real estate on your particular boat use a laminate trimmer. The base of a laminate trimmer is nice and small and it worked very well, on our boat, when used from the outside. The cabin liner on the inside interfered with the base this is why I chose to cut from the outside.
Basically, once adjusted for proper depth of cut, the guide bearing rides along the surface of the template and the blade cuts the fiberglass. It's quick easy and neat but NOT clean.
I advise having a shop vac on board for this job. No matter how you try and contain the dust it makes a HUGE mess. One other tip is to remove your interior cushions before doing this job..
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MAY-2006
The Laminate Trimmer
This little battery operated laminate trimmer is the best $49.00 I've spent in a long time. I own lots of heavy duty professional grade tools from Hitachi, Porter Cable, Milwaukee, Makita & DeWalt but often find my self reaching for my cheap Ryobi ONE+ stuff.
I have yet to kill one of these "budget" tools and I use my Ryobi stuff quite often (professionally). I now have about 10 batteries, $49.99 for two, and two chargers, so I never run out of battery power.
Whether you chose to use a Ryobi, DeWalt, Hitachi or Bosch the small laminate trimmer, vs. a router, is the way to go regardless of brand..
MAY-2006
Ready To Bore The Holes
This photo shows the completed and routed port opening after moving the clamps to complete the full circle. It matches the Template perfectly.
Once the opening is cut leave the template in place and use the built in drill guides to drill the 8 3/8" trim ring holes. You will notice in the picture that I have drilled, from the inside while the template was still in place, many of the eight 3/8 inch trim ring holes already.
MAY-2006
The NFM $29.00 Counter Bore Is Worth It
Once you have drilled the 3/8" holes you need to counter bore into your cabin side exterior 1/2" deep to accommodate the bolt studs on the trim ring. My cabin sides were 1/2 inch deep so I had to go all the way through which is fine.
The NFM counter bore has a 3/8" guide pin, to match the previous 3/8" holes you drilled, and it bores it out to 5/8". It is well worth the $29.00 and is a very high quality & clean cutting tool.
MAY-2006
45 Degree Bearing Guided Chamfer/Bevel Bit
Having learned the art of bedding fittings from some of the masters at Hinckley Yachts I believe in the bevel/chamfer and tighten once method for most things. I don't generally subscribe to the "tighten over a few days to create a gasket" method.
Beveling the edges of the holes does a few things:
1)It forces bedding compounds into the hole, like a funnel, as you tighten the fitting.
2) It creates an o-ring of sealant that is about 6-8 times the thickness of what would be there without a bevel.
3) It allows you to tighten the fitting all the way down without coming back days later to do so which can break the seal that has already cured around the bolts threads.
4) It creates a surface area that forces sealant against and around the bolts threads or shank.
5) It prevents gelcoat crazing and checking around the bolt holes.
To use this process for the ports I used my laminate trimmer and a 45 degree bearing guided bevel/chamfer router bit. The router bits guide bearing fits in the 5/8" hole so I used the laminate trimmer for those holes too.
On these ports, using the butyl, it is very, very difficult to tighten them down all the way at once. I tightened the ports over two days, which is short enough so my polysulfide sealant did not fully harden, but long enough to fully compress the butyl.
WARNING: I differ from the NFM instructions on this particular procedure. NFM says to tighten over a few days letting the sealant harden to form a "gasket" so you make your own choice on how to seal the ports but here is my explanation of why I do it the way I do:
I've been bedding fittings, tighten once or before the bedding is dry, this way for a very long time and never once had a re-leak. The idea that tightening a fitting all the way down squeezes out all the sealant is just not true. Take for example the aluminum valve cover on the Volvo 5 cylinder engine used in the V-70 series and others. This valve cover uses no gasket and only a thin layer of Permatex (Silicone) is required to seal it. You apply the Permatex, install the valve cover, and torques the bolts. Valve cover gaskets are under positive crank case pressure and deck fittings or ports are not! I have used the above method (bevel then tighten at once) on underwater fittings as well and still never had a leak.
Again, it's your choice as to how to seal your ports and I'm merely telling you how I differ from the manufacturer on this one point.
EDIT: If I had to do this job over again I would NOT use the NFM black butyl tape and would instead use Bed-It Butyl Tape in gray. This will completely avoid the need to use both a sealant and butyl. The gray Bed-It Tape is far less messy than the black tape from NFM.
MAY-2006
Depth Of Chamfer/Bevel
This photo shows the depth of the bevel cut. It does not take much to create a good seal..
MAY-2006
The Chamfer / Bevel
Here is a close up of the beveling or chamfering. It runs all the way around the port and around each bolt hole. Every bedded fitting on my boat is, or will be, as I get to them bedded in using this method.
Most times I just use a drill and a chamfer or countersink bit but for big holes like this a laminate trimmer is the way to go. While that bevel may look big it's really only about 1/16 of an inch..
MAY-2006
Dry Fitting & Leveling The Ports
When I routed the holes using the NFM template I made sure it was level with the cabin top. Some boats have a large smooth radius cabin top so you'd need to find a way to measure for level but my boat has a nice square, clean edge to work off of.
Before applying the butyl tape I made sure to line up the ports and make sure they were level by using my combination square. Once they were level I tightened down hard on the clamps making sure to use a block of wood on the inside to prevent scratching the port.
This photo shows me checking the right side of the port with the combination square.
MAY-2006
Dry Fitting & Leveling The Ports 2
Checking the left side of the port for level. You can see, when the camera pulls away, how slight the bevel is. It's there but hard to see in this photo.
Again, CLICK ANY PHOTO TO MAKE IT LARGER
MAY-2006
With Teak Spacer & Without
The port in the foreground of this photo has the teak spacer installed and the port in the distance does not. You can clearly see why the spacers are needed on boats with thin solid glass cabin sides.
The NFM teak spacers are 5/8" thick and by adding them it left about 1/4" of the spigot protruding vs. almost one inch without.
MAY-2006
Teak Trim Rings
These are the NFM teak spacers. They are $40.00 each but are still well worth it. Do yourself a favor and pre-finish them before installation.
MAY-2006
Interior View
This view shows the teak trim ring and the wood blocks for clamping and aligning the port.
MAY-2006
Ready For Butyl
In this photo I'm getting ready to level the port and clamp it down to apply the butyl.
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MAY-2006
Clean The Port & Trim Ring
In the previous photo I had already cleaned & prepped the cabin sides. I can't stressed enough how important cleaning and prepping the surface of the boat is and cleaning the ports is also equally & very important.
That rag, in the photo, was white when I began cleaning this port. Just because they are new does NOT mean they are clean. I wiped the exterior of the spigot and the hull side of the flange with Acetone and there were plenty of cutting oils and grime to be taken away.
If you don't properly clean the stainless you run the risk of a leak. These ports are filthy when they arrive so please do clean them with a non-oily solvent of your choice.
MAY-2006
Wrapping The Butyl
In this picture I have already forced one round of butyl into the gap and I'm working on my second round. I found a silicone kitchen tool, don't tell my wife, that worked well for forcing the butyl into the grove without it sticking to the butyl to badly.
With the teak spacers it's very difficult to wrap the ports spigot first, as NFM illustrates in their instructions, before inserting it. Instead, I chose to clamp the port, level it, then install the butyl from the outside.
Again, I varied from the NFM instructions on this issue and installed my butyl from the outside not the inside but both methods will work.
I applied the butyl from the outside for one major reason. I don't believe in sealing any fitting, installed on a boat, from the interior side of the vessel. If I do get an external leak, between the fitting and hull, I want to know about it! If I sealed or bedded the cabin side of the fitting I may be trapping water or worse diverting it somewhere else because it can't escape out the back side of the fitting. Diversion of water by, internal sealing, creates an almost impossible scenario for tracing external leaks! Even though I don't have cored cabin sides I still chose to only seal from the front of the port to prevent trapping any water in there that could potentially freeze, expand and do damage in the cold Maine winters.. In short, I did not want any sealant between the ports inside flange and the hull only the outside flange, trim ring and the spigot.
In total I was able to get about five pieces of butyl around the spigot drain and two laps of butyl around the rest of the port, but I can assure you, this was NOT easy!
Squeezing in the butyl and seating it took almost 50 minutes per port before I even began to install the trim ring and bolts or clean up the "squeeze out".
Before you even think about installing the butyl & sealant please, for your own sake, clean the fiberglass surface with Acetone or another potent solvent or de-waxer but do wear chemical resistant gloves! If you don't clean the fiberglass & port you may get a leak! I first cleaned with paint thinner then followed that up with acetone.
If your previous ports were installed with silicone (read; BAD) you should, at a minimum, wet sand until you get NO water beading when you spray the surface with water. There is no chemical that will remove the embedded silicone from the gelcoat other than sanding. If anyone knows of one please email me! I've already tried just about every chemical known to man, even stuff only body shops can buy that is specifically intended for removing silicone. IT DOES NOT WORK ON FIBERGLASS either because it's to porous or it eats the gelcoat!
If water beads around where the trim ring is to seal it's NOT clean. I use a spray bottle filled with water for this test and do it every time I re-bed a fitting. Do not skimp on this detail.
MAY-2006
Using The Kitchen Tool
I sure hope my wife does not read this article! Here's the kitchen tool I used for seating the butyl. In combination with the waxed butyl paper this end worked well. The other, with the white silicone "spatula" part removed, worked great for stuffing it in between the hull and port.
I applied all the butyl with the clamps in place. When the butyl is finally installed, and packed in place, you can quickly remove the clamps, install the trim ring then re-place the clamps until you get the machine screws in place.
MAY-2006
Second Round Seating The Butyl
In this photo the second round of butyl is just about ready. You do not want to leave the butyl to thick here or it will squeeze out the OUTER edges of the trim ring and make a huge mess!
I had to redo my first port because I used too much butyl in.
EDIT: If you use a gray butyl tape like Bed-It Tape there is no need for the marine sealant!
You need enough to make a seal, and to squeeze out between the trim ring and the spigot, but not so much that is squeezes out the outer edge of the trim ring..
MAY-2006
Butyl Tip
When installing the butyl you need to understand and know this stuff is STICKY! It's like Silly Putty but tenaciously gooey. Here's the tip. Use the paper that it comes wrapped in to seat it.
You can see how I've forced it into the seam using the paper. When your done simply remove the waxed paper.
MAY-2006
Prepping The Trim Ring - Butyl
Before you can even begin to install the trim ring there are three steps that need to be taken.
The first is to actually clean the trim ring as stated above. The second, pictured, is to wrap butyl around each of the trim ring studs. I found out the hard and messy way that you do not want HUGE globs of butyl around the studs or it will squeeze out the top of the trim ring and make for some messy clean up. I actually re-did my first port because of this.
Seeing as I countersunk each hole I wanted just enough to fill the bevel and a touch more, that's it.
To make the butyl thinner I simply rolled it between my fingers while pulling slightly at the same time, like you would do with a joint, If your not familiar with this action a visit to any college campus will teach you. I then cut it using a knife and a silicone cutting board and wrapped it around each stud.
MAY-2006
Prepping The Trim Ring - Sealant
The next, or third step, in prepping the trim ring, is to apply the sealant. Do not skimp on sealant! Sure it will squeeze out and you will waste a lot of it but it's important that you have enough in there to seal the entire face of the trim ring. I also doubled up around the studs by applying the sealant on top of the butyl rings.
For this task I used 3M 101 which is a one part polysulfide. It has a bond strength of about 140 PSI and an elongation at break of over 400%. I have been using 3M 101 or Sikaflex 291 a lower bonding (220 PSI) single part polyurethane sealant for years and had great success.
I chose to use 3M 101 polysulfide because it's easily removable in the future, never hardens as it's what they used for the UV exposed seams in teak decks. Polysulfides are quite UV resistant by nature, without added UV stabilizers like the polyurethanes need. Even the lowest adhesion polyurethanes like Sikaflex 291, at 221 PSI, offer more adhesion than is necessary in a mechanical fitting which a port is.
NFM recommends, in their instructions, Sikaflex 295UV, a one part polyurethane. The problem I have with 295UV is this. 295UV bonds at 450 PSI (adhesion strength per square inch) which is 150 PSI more than other polyurethanes such as Sikaflex 291 at 221 PSI and 3M 4200 or 3M 4000UV which are both 300 PSI. Anyone who's ever used 3M 4200 knows how difficult a 300 PSI product is to remove let alone a 450 PSI product like Sikaflex 295UV.
I know the owners of NFM have the utmost confidence in their ports but at some point they WILL need to be removed or re-bedded and with a 450 PSI adhesion it will be difficult, quite difficult. Heck, it's even hard to remove stuff bedded with 3M 101 at 140 PSI.
EDIT: 3M 101 has been discontinued. If doing this project over again I would use gray Bed-It Butyl tape and avoid the entire marine sealant process.
MAY-2006
Setting The Trim Ring
Once the butyl is in place and you have prepped the trim ring with a polyurethane or polysulfide of your comfort and choosing it's time to set the trim ring.
If you used the method I outlined it is possible to remove the clamps, for a brief period, after you've seated the butyl tape so you can install the gooped up trim ring.
Once the clamps have been removed slide the trim ring over the ports spigot/flange and re-set the clamps. Do not over tighten them and use just enough pressure to get the machine screws started from the inside.
MAY-2006
3M 101 On Bolt Threads & Tef-Gel On Bolt Head
Why did I used 3M 101 & Tef-Gel on this machine screw?
Over the last 35 years of boating and messing with stainless steel nuts & bolts I've come to know a phenomenon called "thread galling" quite well. Some may not know what this is, even though they may have experienced it.
Thread galling is most prevalent with fasteners made of stainless steel, aluminum, titanium, and other alloys which self-generate an oxide surface film for corrosion protection.
During fastener tightening, as pressure builds between the sliding thread surfaces, protective oxides are flaked, sloughed or perhaps wiped off. These flaked off pieces create an interference or high point and thus seize or lock the nut and bolt together.
This clogging action causes increasing surface adhesion. In the extreme, galling causes seizing or the actual freezing together of the threads. If tightening is continued, the fastener can be twisted off or its threads ripped out.
Some stainless bolt manufacturers actually refer to this phenomenon as "cold welding." Anyone who has seen a bolt and nut seized in this manner understands the nature of this description.
Please use some sort of lubrication for the threads as this is the only way to minimize thread galling.
Galling is a problem that can occur between two un-lubed stainless pieces such as a nut and a bolt. Essentially, as you begin to tighten they bind together never to come apart again. You never know when this will happen it just does.
The last thing I wanted was to "gall" one of the machine screws into the flange as this would require a drill out and re-tap of the trim ring. I could have used Loc-Tite on the threads, to prevent galling, but I know from experience that Tef-Gel or 3M 101 works and it too prevents the bolt from backing out. I used Tef-Gel at the head of the bolt for lubricity for the stainless to stainless mating where the pan head machine screw meets the ports interior flange. This allows a very smooth tightening of the machine screw with no false "grabbing"..
EDIT: With 3M 101 now discontinued I would suggest using Tef-Gel for both the machine screw threads and under the head. I have not found that Tef-Gel has a tendency to loosen over time if properly torqued.
MAY-2006
The DAP CAP
This handy little item is called a DAP CAP and it's available in the Home Depot paint department. It serves two purposes. #1 It can be used to clean up the excess sealant that squeezes out. #2 It fits over the end of an open tube of caulk to seal it for future use.
WARNING: The DAP CAP does not fit Sikaflex nozzles but does work on 3M brand tubes.
MAY-2006
Clean Up The Squeeze
This is how you use the DAP CAP. Once the scoop is full simply wipe it onto a paper towel or rag and toss in a bag lined trash can. Then your ready for your next scoop of goo..
MAY-2006
Day Two Clean Up
I let all my ports sit after the tightening them down and then came back and did the final clean up. For the fine detail cleaning I used my boat chisel.
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MAY-2006
After the Chisel
By letting the 3M 101 set up overnight it was pliable enough to remove with my chisel and yet still soft enough to get a clean edge with a solvent wipe down..
MAY-2006
After The Paint Thinner
Here's the finished edge. I used paint thinner on a terry cloth rag to get that edge. DO NOT soak the rag in the solvent! You do not want the solvent to eat into or soften the sealant through transfer of of the liquid from the rag to the surface.
WARNING: You want just enough solvent to keep the rag damp, to smooth the outer edge of the sealant, that's all.
MAY-2006
Tighten The Bolts
This photo shows the clamp still in place and the bolts inserted about two to three turns. At this point, if you have subscribed to my installation method, you may begin tightening the machine screws in an alternating pattern. If you subscribe to the NFM method of creating a "gasket" follow their instructions.
It's very important, for the seal, and even distribution of sealant under the trim ring, using either method, to tighten the machine screws so the trim ring compresses as evenly as possible.
I find it much easier to tighten until you have some resistance, then stop and wait and repeat. I would move onto another project and come back fifteen minutes later and take another few turns. Doing this allowed the butyl to compress more slowly and evenly than force tightening all the screws immediately.
You'll notice the Tef-Gel around the bolt head which made for easy turning with minimal grabbing of the two surfaces. Once done, I simply wiped this excess up with paint thinner.
MAY-2006
The Final Result
Now that the ports are in I was finally able to remove the cover and snap a photo.
Good luck!!
MAY-2006
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