This article is written by Eagle customer, Colin Shead, whose windows we recently refurbished. The article is written for the Moody Owners Association magazine and is published here with kind permission.
For years I have been putting off sorting the leaking windows on Toodle Pip, preferring instead to use silicone sealant and Captain Tolley’s Creeping Crack Cure to try and stop the leaks due to the original window sealant (i.e. from the Acrylic window to frame) drying out and cracking, allowing annoying dribbles of water into the cabin. Needless to say the original windows (1986) were also heavily crazed due to solar damage.
The Corona Virus lockdown, with the boat in the yard, gave us the opportunity to do the job in the summer. Eagle Boat Windows had previously made a very good job of reglazing the hatches, so I contacted them again and was pleasantly surprised by their quote to reglaze the frames; if I could take them out !
Frame Design
The frames are in two parts see section sketch below (not to scale). The outer alloy frame carries the acrylic window and projects through the cabin side into the boat. The inner frame fits snugly around the outer frame when it is in position. The outer frame is secured to the inner frame with stainless screws, which grip the GRP of the cabin side as well as having a couple of turns into the inner alloy frame, so it’s all clamped together with the outer frame sealed to the cabin side with mastic sealant. The inner frame also traps the headlining into position.
Frame Removal
There are 25/26 screws in each window. Stainless in alloy is always problematic due to corrosion in sea water.
First step is to get a screwdriver that fits really well, my screws had Pozidrive No. 2 heads. I used a decent quality power driver bit in a hand screwdriver. Technique is to whack the screwdriver with a hammer before attempting to turn the screws out, this hopefully breaks any corrosion of the screw thread into the frame. Go gently ! The screws shear off easily !
In my case all but four screws turned out quite easily, the sealant used had protected the screws from the sea water. Three screws sheared off in the frame corners where sea water must have got in (see later section) and one screw had been butchered by a previous owner who had obviously tried tightening the screws to stop leaks, to no avail no doubt, as I don’t believe these windows ever leak from the outside edge.
I drilled the head off the butchered screw with cobalt steel drills, taking care not to damage the much softer alloy frame. Later I removed the broken off screw studs, see later section.
I used a narrow filling knife, with the edge filed into a blunt chisel point. Starting from a corner, with the chisel edge outward, simply tap the scraper between the cabin side and the outer frame, and gently lever the frame outwards.
If you take care no damage to the gelcoat or frame results. The frames in my case came unstuck quite easily, the sealant was still very sticky and messy, and would give as you worked the scraper along the top edge of the frame, warm weather helps a lot. Once the top edge was free it was easy to slowly work the frame out. Go gently as you obviously do not want to bend the alloy.
Extracting the Broken Screws
All the broken screws broke off at the level of the cabin side, so there was no way of gripping them for easy removal.
The glass fibre of the cabin side is about 6mm thick, so I used a 12mm hole drill in a drill guide to drill out a 12mm core of glass-fibre around the stuck screw. After fiddling the core out bit by bit with a small screwdriver/pliers you are left with the screw stud, still firmly screwed/corroded into the alloy inner frame.
The 12mm hole drill I bought cheaply on eBay (£3) and I made up the drill guide using a small off cut of 5mm thick hardwood. Remove the pilot drill before drilling the GRP.
The photos below show the drill guide clamped into position, and after cutting showing broken off self-tapping screw studs.
A spot of PlusGas or WD40 and wiggling with pliers through the 12mm hole got some of the studs out. Others were welded more solidly into the frame!! On the forward cabin window, it was easy now to lift the inner frame off, being careful about the headlining. Using a small pair of mole grips the screw studs were carefully removed, by wiggling a little and turning. Try not to break them off as drilling stainless screws out of an alloy frame is very difficult.
Screw studs stuck in the aft cabin window frame were more difficult, as the inner frame is trapped behind the companion way bulkhead and cannot be removed. From inside the cabin, I wedged the inner frame out sufficiently so I could get a small pair of mole grips onto the broken studs. I had used paper towel in the frame channel soaked in WD40 overnight to assist, and once I managed to get a good grip on the studs, I was able to remove them.
I refilled the 12mm holes with marine filler, having first stuck a matchstick into the inner frame screw hole. This makes it easy to relocate the hole in the inner frame, you can simply drill out to 3mm when the filler is fully cured to take a new screw. I used a detail sander to sand down the surface of the filler when cured to be flush with the gel coat. The filled hole is hidden under the outer frame when refitted, so finish is unimportant.
Covering the Window Apertures
I cut some heavy gauge plastic sheet to size and secured with Duck Tape. This was fine, but the Duck Tape does leave a sticky residue on the cabin sides which has to be scraped off then wiped off with white spirit or similar.
Cleaning Off the Old Mastic
The old mastic when left for a day or forms a skin, which enables the bulk of it to be easily scraped off using a plastic or blunt steel scraper. Any residue can be cleaned off using white spirit on a rag.
Eagle Boat Windows prefer that you clean off the mastic on the frames before sending them for re-glazing, and you also have to clean off the old sealant on the cabin side.
I left the sealant residue on the cabin sides until I was ready to refit the windows. By then the sealant had dried out quite a bit and was easy to scrape off.
Dealing with the Headlining
The Headlining on the cabin sides is trapped under the inner window frame. If the inner frame is removed (or falls down when the screws are removed), it’s likely that you will find that the headlining has come unstuck from the cabin side and droops down. If you carefully use some ‘super double sided tape’, the type used to fix car accessories etc., along the edge, it can be temporarily secured in position whilst the window is being replaced, and the screws done up.
Cabin Side Vinyl Graphics
It is possible that you will damage the edges of the Vinyl graphics when you change the windows unless you are very careful. I was going to replace mine anyway due to sun and sailing boot damage over the past 16 years, so I was not concerned.
Fitting the Re-Glazed Windows (two people essential)
First off, get some new screws, personally I would not attempt to use the old ones. I bought 200 stainless 19mm No. 6 screws with Torx T10 heads for about £9 on eBay. Torx heads are much easier to use than Pozidrive etc. as there is no chance of the screwdriver slipping. Just make sure the thread pitch on the new screws is the same as that on the old screws, so that the screws take up nicely in the original holes.
Eagle Boat Windows supplied cartridges of ARBOmast BR Butyl Rubber sealant, and some plastic scrapers made from Perspex off-cuts. Two cartridges are needed on a Moody 28. Use plenty of sealant, easier to clean up the excess that deal with leaks afterwards!
Right - ARBOmast BR Butyl Rubber sealant and an Eagle Boat Windows supplied scraper that works really well at cleaning off old and excess sealant without damaging the gel coat.
Initially offer the window up without sealant to the boat, to make sure that the frame is not distorted etc. Whilst held in position get the crew inside the boat to make sure that the inner frame will fit snugly over the outer frame.
If all is well, lay the window on an old towel on the deck, and gun around a 6/7mm diameter bead of sealant around the frame along the line of the screw holes. Put extra sealant around the frame corners. It is super sticky stuff, gets everywhere unless you are careful.
Offer the frame back on to the boat and push the frame onto the cabin side. Insert a few screws along top and bottom edges through the frame and into the holes in the GRP and into the inner frame. Whilst you are doing this it is essential for your crew to push the inner frame against the cabin side, close by the screws you are tightening, to make sure that the screws fully engage into the inner alloy frame. Go round the frame inserting screws and tightening gently as the screws engage with the inner frame. Leave the corners till last. Be careful on the corners to tighten the corner screws evenly and progressively, as otherwise you may distort the frame joint. When all the screws are located work around the frame progressively tightening. Don’t over-tighten, the surplus sealant with gently ooze out of the frame side. Make sure that you do see sealant all the way around the frame, if not you have not put enough sealant on in the first place !
Lots of sealant will likely ooze out of the joint and through the screw holes. Looks a mess at this point !
After 20/30 minutes progressively tighten the screws a wee bit more, so that they all feel to be at the same tightening torque, then walk away ! The edge of the alloy frame should be well seated down onto the cabin side, with no gaps, just a line of sealant. Don’t be tempted to clean up the surplus sealant at this time, it will get everywhere.
After a day or two you can scrape off most of the surplus sealant as it will have skinned over a bit (use the Eagle Boat Windows supplied scrapers). Remove the residue with white spirit on a rag.
Left - Frame and sticky sealant after tightening screws !
Note that the sealant is the most sticky stuff ever !
If you are of a certain generation you will recall cheese fondue dips; well the Butyl Rubber sealant resembles that on overdrive !
You need lots of patience, old rags, and kitchen paper towel to get rid of the excess. It is fortunate that it is easily cleaned off with white spirit which is harmless to gel coat and the new acrylic windows.
After a good clean up, you are finished, and hopefully you have some nice looking windows which do not leak !!
Colin Shead - July 2020
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