Category: Miscellaneous Projects

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Replacing lens on Atkins & Hoyle hatches

I will update this page with pictures and more info once I complete the project. My boat is an A32 but it shares the same size hatches as many other models.

Material

As per OEM, I’m using 2074 (15% grey) grey cast acrylic (Plexiglass or Acrylite brand). Cast acrylic is stronger and more scratch reistant than polycarbonites (like Lexan) and has a much lower expansion coefficient (less prone to leakage). All hatches are 1/2 inch (12 mm)  thick.

I also have the DXF files for laser cutting the plastic:

File technical details:

– line color: RGB Red|
– line width (stroke):  .01mm
– file format: AutoCAD DXF R14

Large Hatch
25 1/4 inches square (641.35mm)
Corner radius: 2 inches (50.8mm)
DXF file: https://www.alohaowners.com/dloads/LargeHatchFinal.dxf

Medium Hatch
20 5/8 inches square (523.875mm)
Corner radius: 1 3/4 inches (44.45mm)
DXF file: https://www.alohaowners.com/dloads/MediumHatchFinal.dxf

Small Hatch 
11 1/2 inches square (291.1mm)
Corner radius: 1 1/4 inches (31.75mm)
Note, hinge and spring notches are included
DXF file: https://www.alohaowners.com/dloads/SmallHatchFinal.dxf

If you want to view or print these files, download “FreeCAD”. It’s free and works like a charm. Get it here: https://www.freecadweb.org/

Instructions (from a conversation with A & H):

There is only one product combination they use on OEM and rebuilds:

– Sikaflex 295 UV adhesive/sealer
– Acrylic edge MUST be primed with Sika’s 209N primer.
– Aluminum MUST be cleaned/prepped with Sika’s 205 cleaner/activator

Do not use ANYTHING other than the 205 cleaner on the aluminum bonding surfaces (alcohol, mineral spirits, etc will affect the bond).

Be SURE the Sika products are not expired. This is critical with the 209N primer. Expiry dates are marked on the products. It may be difficult to find fresh 209N.

The aluminum bonding surfaces should be free of any sealant and lightly sanded before using the 205 cleaner.

The easy/mess-free way to install the new lens is with 3M VHB tape. Use  1/4 or 3/8 wide on the lower flange to bond the lens in alignment and make it easy to fill the vertical gap with 295 UV. The tape will also keep the 295 from leaking out the bottom.

Be sure to remove an inch of the protective cover from the bottom (people have forgotten).

Be sure to prime the edge of the lens too (note that working time is short before the 295UV needs to be in place).

Drop the lens into place and press gently to seat it onto the VHB tape. The easy way to perfectly center the lens when dropping onto the VHB tape is to make shims to use on all four sides. Be precise as once the lens touches the VHB tape it’s almost impossible to remove.

Mask as needed and fill the vertical gap with 295UV. Use a gloved finger to smooth/remove excess. Lens should be slightly proud of the frame.

Close hatch and dog it down so proper alignment is maintained while the 295UV cures (at least a few days – a week is better).

It’s a precise process but it’s how the OEM does it and considering the cost and effort to replace a lens, I think it’s worth following.

Regarding VHB tape. Most production boats now only use VHB to mount fixed windows. It’s that strong. So it will also provide considerable adhesion to the new lens.

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PSS (Packless Sealing System) Shaft Seal

PSS (Packless Sealing System) Shaft Seal from PYI Inc. This does not drip, and requires little or no maintenance or adjustment.

A possible downside is that if the packing in a stuffing box starts to fail, you simply get an increased drip rate. If a PSS fails, it usually does so with a very substantial inflow that is difficult to stop, and that your bilge pump may even have difficulty keeping up with.

Written by Liam Fitzgerald

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Your Own Collapsible Lazy Jax

Here is an outline of the design of a collapsible lazy jax which Richard Gegenwarth is putting on his Aloha 8.2 #139 Dulcinea. Except that the total length of line required would change, the same arrangement could be applied to any model of Aloha.

Mount a cheek block (e.g. Ronstan 30151) on the mast below the spreaders on port and starboard.

A cleat (e.g. Ronstan RF5106 combination fairlead/V-cleat) is needed at a convenient spot on the lower section of the mast, again port and starboard.

There are three eye straps (e.g. RF134) on the bottom of the boom in front of the vang (D), in front of the mainsheet (C) and half way in between (A).

The length of Line#1 is twice the distance from (A) to (F) to (C). Thus when pulled forward, those lines lie along the boom. That line is connected to eye strap (C) at its mid-point with a simple loop.

You need two of Line#2 (one port, one starboard) of length equal to (F) to cheek block and back to the cleat. Line#2 has a stainless steel thimble on one end and a stopper knot on the other end.

The length of Line#3 is twice the distance from ( D) to (F). It is connected to the eye strap (D) at mid-point by a simple loop. There is a 1″ x ¼” stainless steel ring on each end attached to the line with a stainless steel thimble.

To set up – attach Line#3 at it’s mid-point to eye strap (D) – attach Line#2s over cheek blocks to the cleats (port and starboard) – attach Line#1 at it’s mid-point to eye-strap (C) – now thread Line#1 through the port Line#2 thimble (B) and port Line#3 stainless ring (E) and attach to eye strap (A), then do the same on the starboard side.

When you pull on the two Line#2s to raise the structure you will have a problem with the rings – they fall down. Hence “Jamstoppers” (they look like split balls that get screwed together) need to be attached at an appropriate spot on Line#1 to port and starboard.

One last thing. To collapse the structure, release the lines on the mast and pull the rings forward. Then attach the rings and thimble to the mast using a piece of shock cord with plastic hooks or whatever works for you. The shock cord can be attached to the mast with an eye strap for example.

I figured that I needed about 90 ft of 1/4inch line so I bought about 110feet. Total cost was about $70 with most of the gear purchased through SailNet.

Written by Richard Gegenwarth

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Aloha Cabin Side Logo

Many Alohas came with the name displayed on the cabin side. If yours either didn’t, or they have faded or worn away, we can help provide you with replacements.

This photo shows the transfers I had made for “Bliss”, based on a tracing which Dennis Clarke kindly provided from the original transfers on his 28, which he replaced a while ago.

Get some made!

To get these made, I created a Corel Draw file with an image the exact size (approx 21cm x 7.5 cm) of the originals. Many sign makers can use a Corel file as a starting point to import the logo into their own software, although they usually spend some time “cleaning up” the edges to produce the best result. The sign-maker I used charged CDN $35 to tidy up the artwork and CDN $20 for 4 logos themselves, plus tax.

If you want to approach a sign-maker local to you, then download either the  gif file by clicking here

Written by Keith Denham