Avid readers of the blog will be aware that many many moons ago (Aug 2020) I removed the 1980's composite Canpa hatch from my own boat, the Halmatic 30 Liberte Boo (see Blog - Lids4Lend in Practice - Fitting a Lifeboat Lid) . At the time (all together) I had intended to complete the job quite soon after but clearly failed. Covid is a convenient excuse but to be honest I couldn't decide what to do and left one of our Lifeboat Lids (see Lids4Lend) in place for the duration.
I had acquired some Ocean 60 hatches in good condition for refurb (from an Oyster 82 no less) but as these had flange bases (mine was flat) this never quite happened. Eventually, I decided to refurb the Canpa, so gave it to Tim. He replaced and resealed the acrylic and I spruced up the faded composite exterior with a couple of coats in satin black from a can of Plastikote paint (we use this on handles too).
So now I was ready for the refitting, to put into practice the advice we pass on daily. Hopefully you can benefit from my experience.
As you can see, the whole deck was looking rather sad after wintering in the yard....
Step 1 - Clean up and prepare for battle
With the Lifeboat lid removed I cleaned up the deck surround with IPA (Iso Propyl Alcohol) and likewise applied this to the underside of the hatch base too. I then placed the hatch in position for a dry fit, with a couple of screws in place. Next, I put a line of masking tape around the base. With hindsight, doubling this up from 25mm to 50mm may be better if doing this).
Then I removed the hatch.
Lastly here, I put a little bedding compound into the screw
holes on the deck. Note that if using interscrews you would not do this as you should try and keep the threaded ends of the machine screws free of compound to avoid this getting introduced to the captive bush parts.
Step 2 - Add the goo
So first I put a line of the ARBO GZ (butyl) tape (white in photo) around the inner edge of the flat base. This serves two purposes; first it would hopefully prevent bedding compound from leaking into the hatch opening and second it would ensure at least 1mm of the bedding compound remained between the base and deck when the base is screwed down (as the underside of the base is flat).
Then I applied the bedding compound (ARBOmast BR - grey in photo), applying more, rather than less to be safe. In hindsight I would suggest not putting compound too close to the outer edge as I found when I picked up the hatch my hands touched the goo and it started to get a bit messy.
Step 3 - Contact
I now picked up the hatch, turned it over and placed it as level and centrally (using the blue masking tape as a guide) onto the deck opening. I then added the screws and started to apply pressure, going around several times to gradually wind the hatch down. Clearly at this point bedding compound starts to squeeze out. Let it and under no circumstances attempt to clean this up. Resist!
Step 4 - Mop up the stragglers
A client said using bedding compound reminded him of a 1980's fondue party, specifically the stringy cheese that just hangs on to everything it contacts. I concur.
Inevitably you (as I) will touch this compound in some areas and the result will be like a spiders web of stringy lines sticking to everything in between. Small deposits can at this stage easily be wiped away with a cloth liberally doused in White Spirit. If the deposit is significant (you'll work out what this means) then leave it as you'll just turn a local mess into a wider mess.
Step 5 - Go away
Now leave for at least 24 hours, or a week if you can so that the excess bedding compound can skin over and harden.
Step 6 - Remove excess and clean up
I used one of our acrylic scrapers but a shaped piece of wood or plastic will work as well. The aim it to prise the over-spill away from the hatch edge and onto the masking tape.
Now get a suitably large bag or cardboard box into which the excess laden masking tape can be removed and in the same motion deposited in said bag/box without touching anything in between.
Do as above. Once all the excess/masking tape is safely removed and disposed of you can start the cleaning up. Again a cloth and white spirit can be used to wipe up and smooth off the hatch/compound/deck join.
You will probably find that bedding compound has oozed past your screw heads. If excessive you may have to clean this off in stages as cleaning a lump in one go is likely to result in more rather than less mess, such is the nature of bedding compound. Remove as much as you can with a stick/scraper and then leave to skin over, come back and repeat. Patience is a virtue.
Step 7 - Admire your work
First, at this point I removed the protective covers we'd placed on the acrylic (we do this for refurbed hatches to help avoid damage during transport/refitting). I then gave the new acrylic a final clean.
Good as new - well almost. I'd even cleaned the deck too :-)