Installing Raymarine ST60 Instruments

[Tim]

The new owner of the Daysailor wanted some instruments installed. I chose the Raymarine ST60 instrument pack that includes knotmeter, depthsounder, and wind instruments.

When I opened the packaging, I was startled to find that the instruments required a 3.5" hole for installation--huge. Since I planned to install the instruments in the mahogany cockpit bulkhead, I was understandably nervous about boring such large holes in the varnished surface.

Eventually, I had no other choice but to just do it. I proceeded with great care to avoid damage; it doesn't take much for a large hole saw to bind and chew up the surrounding surface.

Here is the raised panel bulkhead before beginning the installation.



Next, I covered the whole area with masking tape for protection against chipout.



The instruments include drilling templates, which I taped to the bulkhead in the proposed configuration to see how things would fit. Fortunately, there was just enough room for all three instruments in the field of the raised panel.



Next, I marked the centers of the holes with an awl. Each instrument requires the large 3.5" hole for the main body, plus two smaller holes (3/16") for the studs that secure the instrument. Once I had marked the holes, I had no choice but to go ahead and drill.

I used a new 3.5" holesaw chucked into my big, slow-speed right angle drill. I began on the exterior, drilling very slowly and carefully until the hole saw bit well into the wood. Once I had the hole partially cut, I bored the center hole all the way through with a 1/4" bit, then brought the big drill inside the boat to start the hole cutting from inside as well; this would prevent the plug from chipping out the interior surface.



Finally, after some minutes, I managed to bore all three huge holes successfully. With the thick solid wood panel, the overall thickness of the bulkhead was over 2".



Of course, the studs supplied with the instruments were too short for my thick bulkhead, so I had to modify some longer screws to replace the studs. Since I couldn't find screws with a fine-enough thread (the studs were some thread count finer than 8-32), I used 8-32 screws that I managed to thread into the receptacles on the back of the instrument, thanks to the soft brass threads.

Here are the instruments completely installed, with covers on.



And here they are with the covers removed.

[JetStream]

Really looks nice Tim! For others contemplating a similar installation, it is important to know that the mounting studs for the ST-60 instruments are not symmetrically located above and below center. You really need to use the supplied template as Tim did. The studs have a metric thread with no proper way to make sure they are threaded all the way in. I've often wondered if you should leave the fancy covers on when the wind is expected to be over 40 knots at the mooring. At what point will they blow off and require an expensive replacement?

[Tim]

One really has to wonder why these instruments are designed the way they are. To me, the size of the opening required seems beyond excessive; there would be plenty of room for the connections if the hole was half the size.

I wasn't aware of the asymmetrical position of the studs; with the template, it wasn't an issue, but again: one must wonder what is gained by making these asymmetrical when all logic would dictate that they were symmetrical.

Electronics designers are apparently isolated in their own little world where end-user function is irrelevant.

As to the covers, they do seem to be fairly tight at this point, but will surely become a bit sloppier over time. They sure fit better than the ones on my Horizon instruments on Glissando.

I like the look of these ST60s, and I know they're nice instruments. But I wouldn't have ordered them had I known about the cutout size.

[Robert The Gray]

it always seems to amaze me that these instruments have not gone through any design refinements as far as size. I am longing for a 2" diameter depth/compass heading/speed log with small remote sending units Three little numbers! Casio can make a watch that connects to an atomic clock, you can produce a feature film on a laptop Mac, and it seems that they will make a gps soon that fits in your ear! Why are these things so big? Whoops, I am in the ramble rant section now. Great job tim, each of your process posts are are like handouts for journeyman/master boat class. Thanks for all the extra effort for the photos and the writing. All our boats are lucky to have you.

R.

[dasein668]

Hehe I was eyeing those babies in the box when I was over there reworking my boat cover. Tim wasn't around and I was thinking, "nah, he'd never notice if I replaced them with the old beat-up instruments from my boat, would he?"

The install looks great Tim, though I do prefer the plain raised panel look with no instruments!

[Tim]

The install looks great Tim, though I do prefer the plain raised panel look with no instruments!

Me too!

I was thinking, "nah, he'd never notice if I replaced them with the old beat-up instruments from my boat, would he?"

I'm sure I never would have noticed.