A quick fix for an old speed log--thanks Dan

[Oldrig]

Here's a simple tip for an instrument LCD that doesn't seem to be working: try attaching a piece of stick-on polarizing film to the screen.

Creme Brulee still has her original 29-year-old Signet instruments. The depth sounder has always worked, but the numbers on the speed log have been broken up and mostly illegible since before I owned her (2003). The previous owner simply told me, "That thing doesn't work. Forget it."

Still, despite my instructions to the contrary, the boatyard has consistently cleaned or replaced the rotor if it was clogged or broken. A while back, I noticed that I could read some numbers some of the time, provided I was wearing polarized sunglasses and the sun was at certain angles.

Last year, when Dan "Adriftatsea" was helping me install my tiller pilot, he suggested I might try getting some stick-on polarizing film and applying it to the non-functional LCD screen.

This year I finally got around to doing so. I ordered some optical-quality polarizing screen ($16 plus shipping for the smallest sheet available), cleaned off the LCD and applied the polarizer.

Now I get a fairly consistent reading from the old speed log. It's useful when trimming sails or estimating current velocities--but I still use my GPS for SOG, the most important number as far as I'm concerned. The small amount of cash I spent on the polarizing screen sure beats the cost of replacing the display unit--whether with a Signet or a newer speed log.

BTW, an oil-delivery tube burst on my engine last weekend, so poor old Creme Brulee won't be out on the water until sometime next week. (That's assuming that I turned off the engine in time--which I think I did.)

--Joe

[AdriftAtSea]

Glad to help Joe.  Sorry to hear about the oil tube. Keeping my fingers crossed for you and Creme Brulee. :)

[Amgine]

Sounds like a great fix!

Njordson has Datamarine circular instruments, and the depth sounder is slowly but steadily becoming unusable. Anyone have any ideas  as to a replacement instrument which will fit the same hole in the cabin bulkhead?

Best of luck with the engine, Old Rig...

Edited 'cuz my mind is a seive: I have datamarine instruments not Horizon

[Oldrig]

Amgine:

Signet Marine is still in business, in California. Their website, www.signetmarine.com gives prices for various instruments. They will also service the original equipment.

However, it seems like they want more than $400 for the cockpit unit for their round knot logs. So, for the time being, I'm using the stick-on polarizing film.

DataMarine is out of business. However, there's a company in Pocasset, MA (where I grew up) that specializes in servicing DataMarine gear and sells replacements that fit the DataMarine cutouts.

Their website is: www.dmimarine.com.

I have not dealt with them. I sent an e-mail asking if their products could be used to replace Signet instruments, but never got a reply. However, they do have phone numbers on their website (just remember you're calling the East Coast from the West Coast).

Best of luck!

--Joe

[AdriftAtSea]

One point I'd make... if you normally wear polarized sunglasses—which are invaluable on the water for both cutting glare and helping you spot deadheads and other obstacles that may be submersed slightly—repairing the instrument with "circular" polarizing film rather than the traditional "linear" polarizing film will make the instruments easier to read with the polarized glasses on.

A "circular" polarizer is basically a regular "linear" polarizer with a quarter-wave plate laminated to it.  Be aware that circular polarizer films can really only go on one way, where linear polarizers can go on in either direction.

[Oldrig]

Dan,

I wish I had known that when I ordered my polarizing screen.

I DO wear polarizing glasses almost every time I'm on the water--except in fog and cloudy weather.

However, the film that I put on the LCD screen seems to help, whether or not I'm wearing polarizing glasses.

--Joe

[Tim]

Joe do you have a link for that polarizing film?

thanks Tim

[AdriftAtSea]

Joe—

I wish I had mentioned it previously, but hadn't thought about it until just this past week... since I just got some new glasses, and the polarization angle is a bit different on them from my old glasses.

Tim—

Try this place...

Dan,

I wish I had known that when I ordered my polarizing screen.

I DO wear polarizing glasses almost every time I'm on the water--except in fog and cloudy weather.

However, the film that I put on the LCD screen seems to help, whether or not I'm wearing polarizing glasses.

--Joe

[Oldrig]

Hey Tim:

Dan found the place! That's where I ordered my polarizing film.

How big is your LCD screen?

I had to order an 8 x 10 sheet and only used a small piece.

--Joe

[Tim]

LOL 3"x1" ;D My truck radio is impossible to read with my sunglasses on

I haven't had the problem with my fishfinder or gps because I can move them around easily, but I thought that it would be good to have some for any future problem.

I would gladly share in your cost and buy a piece from you.

PM if you are interested, but it is not a big deal either way.

Tim