Cutting Access Ports

[Guest Dennis M]

Good morning, I just cut out the access port on my fwd bulkhead with a jig saw. The plywood face threw off splinters in a frightful manner and the scars will need to be faired with epoxy putty. While I had good intentions for the perfect shape of the port, I must say that it looks rather postmodernish in a unappealing way and I am at a loss as to how to set things right without cutting a new bulkhead. Question: what tool is best for this type of work?

Thanks, Dennis

[Ken_Potts]

I'm not sure if there is a better tool than a jigsaw for cutting things like ports.  There are 2 ways I know of to cut down on splintering.  You can use a razor knife to cut into the first veneer of the plywood along the outline of the hole you're cutting then run the jigsaw just inside that cut line (if you cross the cut line you'll get splintering).  And use a sharp, fine-tooth blade.

[Tom Lathrop]

You should use a fine tooth metal cutting blade for this work and don't use any orbital action.  What Ken suggests will also help but it can only work on one side of the cut.  That is fine if the cutout is to be scraped.  Laying on a light coat of epoxy to seal the fibers is also a good idea. 

[Guest Dennis M]

Thank you, Tom and Ken. ~Dennis

[Ken_Potts]

  I like Tom's advice more - Thanks Tom.

[Guest Dennis M]

I just used the fine tooth metal jigsaw blade with no orbital action, and the blade cleaned up the cut nicely. A little sand paper did wonders for the edges and it looks pretty ship shape now. It is a little bigger than originally drawn, but not by much. Thanks again for the help.  ~Dennis

[Hirilonde]

I keep a package of Bosch "backwards teeth" blades for occasional use on plywood where I need a finished edge on the side I am cutting from.  The blades cut on the down stroke instead of up stroke.  The result is excellent but it is difficult to get used to using them.  The saw tries to jump off the wood on the down stroke and consistent significant pressure against the material is needed to avoid this.  I also like the knife scribe idea, but it may be hard to be accurate doing this for a circle.  A straight line is easy as you can use a straight edge to control the knife.  Definitely seal the new exposed edge as Tom suggests.

[Peter HK]

The cleanest standard cut blades I've come across are the Bosch T101AO labelled "clean for wood". Not perfect but pretty good.

but it may be hard to be accurate doing this for a circle.

One technique for neat circles- say for a plastic inspection port- is a router with a small diameter straight cut piece and an arm on the router with a pin to fit in a hole in the centre of the circle.

Peter HK

[Christopher M-K]

As a neophyte boatbuilder, I don't have any tips of my own to add to the list. But as a pretty experienced web surfer I can contribute the following:

http://fivenineclimber.com/boats_sailing/articles/hatch_job.htm

There you will find a nice little write-up by Jan Nikolaisen on just this topic.

I found the other articles there helpful as well.

[maligno]

Black and Decker has "hollow-ground" jigsaw blades with different teeth counts that make very clean cuts in plywood and laminates.

[SUKIE]

Perhaps I'm being old fashioned, but I do cuts like that by hand, with a fine toothed, thin bladed saw. I imagine if one were to also seal with epoxy first it would be a flawless cut.  Of course, I don't have the power tool skills that most of you do, and the manual cut takes much longer.

[Apteryx]

That bulkhead hatch is now an option in Graham's CS17 kit, and that's what I'm going with.

I've been thinking about adding some extra stowage, too.  For instance, port and starboard above the seats in that same aft bulkhead.  An opening maybe 12 inches wide and ten inches tall, whatever would fit and still leave adequate strength in the bulkhead - I don't have the plans in front of me to see the available dimensions.  Behind the opening a box, open to the front with the bottom side sloped to spill water back out, watertight, otherwise.  Either a net or a fiddle to keep stuff in there.  Binoculars, air horn, that sort of stuff.

On either side of the mizzen, an open plank box structure on the under side of the thwart, open to the rear, this one with the bottom slanted away from the open face to help keep stuff from falling out.

It would be nice to have a long skinny place to keep rolled-up charts.  Maybe a shelf hung on the underside of the aft deck, accessible through that bulkhead hatch.  Before closing up the after deck, some horn cleats in there to hang spare cordage, maybe a shelf port and starboard, understated recessed lighting and discrete wiring troughs for the home theater system.  Just kidding, of course, the theater is in the guest spaces forward, not in the captain's suite for crying out loud.

While daydreaming, how about four rods leading radially from the center of that bulkhead hatch, linked to a rotating piece on the backside of hatch handle.  Turn the handle to set or release four catches simultaneously.  In case the latch mechanism failed I guess a battery powered sawzall would be a workable backup.  And a big supply of kleenex, 'cause I'd cry like a baby...  ;D

Southern Skimmer has a box-like thing beside her mizzen that I suppose is a shade and spray shield for a GPS.  That sounds like a good idea, too, but it would have to be out of the way of the mainsheet, aft-led main snotter, and any other rigging on the mizzen thwart.  Maybe a GPS housing on one side of the mizzen, a compass on the other.

There's some room under the side decks, too, isn't there?  Along the length of the cockpit seats?  Seems like some possibilities for organized stowage there, too.

My present vessel, a Horizon Cat, has quite spoiled me on capacity.  When I pack for a week there's very little left unsecured or laying about, and I'd like to get as close to that as possible on my emerging Core Sound.

[Charlie Jones]

Yes- that's a spray shield/box for a GPS on Skimmer- we did a quick modification to it in my shop pre- Texas 200.

[paul_stewart]

Charlie,

Are there photos somewhere (we can see) of that GPS box on the Skimmer?  Thanks..

--Paul

[Guest Dennis M]

Here is the drawing of the hatch that Graham sent me and I used for the fwd bulkhead. Since we are on the subject of hatches, what gasket material would one use? Also, what would one recommend to use as latches? Thanks, Dennis.

[Greg Luckett]

Dennis,

I bought a circle cutter for my RotoZip to make the access holes in my S12 seats and forepeak and will be posting some pics of that in the thread about its building.  I did not have the forsight to cut them prior to assembly but did think of it before the seats were installed.

[Charlie Jones]

Only if Graham has some. The day we were doing the mods we were sorta rushed because this was sitting in my front yard, with a bunch of sailors waiting for us so they could head south again. ;D

[Charlie Jones]

Dennis- at ACE Hardware we found some 1/2 inch sticky back foam tape- (harder stuff-NOT the soft foam) that we used inside the hatches on our 25 footer. Worked very well. That type thing should do quite well to seal that hatch. Remember though- you'll have to allow for it's thickness when you do the flange.

Also- from the drawing it looks like the latches are the standard metal twist type turn buttons. You can buy them in many marine outlets. One is shown on page 560 of the 2007 WEST Marine catalog, called a "door button" Graham may even be able to supply them- check with Carla.

You could also just make wooden turn buttons that would do the same thing.

[Tom Lathrop]

Charlie,

I have had the best luck with truck camper top sealing tape.  It is pretty wide and I usually have to cut it to the width I want but it works well.  It is the dense foam type and the stick seems to hold up well.  I use it to seal the large plywood access covers to fuel and water tanks in the cockpit of powerboats and it works well there as well as seat hatches in B&B sailboats.  All of these tapes should be compressed a bit lengthwise when installing to prevent them moving over time.  There is a tendency to stretch them slightly when installing and memory will draw joints open.

[Charlie Jones]

Tom- it's been so long since I had a topper on one of my pickups I forget about that stuff. You're right - that IS good foam. I'll try to keep that in the online memory banks, instead of offsite storage ;D