JumbleDuck
Well-known member
I want to buy one of those laser-sighted IR thermometer gadgets to keep an eye on my stern gland temperature. Loads of different models on eBay, starting at around a tenner. Any recommendations or horror stories?
Laser Thermometer
- Thread starter JumbleDuck
- Start date
pvb
Well-known member
I bought one from Maplin a few years ago, about 30 quid I think. Excellent! Have used it at home and on the boat. Recently lent it to a mate who'd installed underfloor heating and who wanted to check temperatures.
JumbleDuck
Well-known member
ProDave
Well-known member
I bought an ebay one for under £10 from Hong Kong
Took a while to get here but it works fine.
Took a while to get here but it works fine.
pvb
Well-known member
One of these?
Yes, very similar.
Rigger Mortice
N/A
They're fine, but they do register the temperature over a beam, not just at the dot. In other words you need to get in reasonably close to read temperature at one spot.
TBH for that application I would be looking at an ordinary digital thermometer. Stick the sensor on and feed the wire through to a convenient mounting point for the display.
Unless you want to check the temperature of the rotating parts....
TBH for that application I would be looking at an ordinary digital thermometer. Stick the sensor on and feed the wire through to a convenient mounting point for the display.
Unless you want to check the temperature of the rotating parts....
daveyw
Active member
Also, they don't work very well on shiny surfaces. You need to stick a bit of black insulation tape on it first or paint it black for a good result.
prof pat pending
Well-known member
I would look at something like these
http://www.burtonpower.com/parts-by...l-instrumentation/temperature-indicators.html
You stick one on in the area you are interested in. It stays at the maximum temperature seen, so you only need to replace it if it exceeds at temperature you are happy with.
It doesn't matter if you forget to read it and go back later, the max temp seen will always be there until it is exceeded
They come in a number of ranges, so may sure that you buy the right set
http://www.burtonpower.com/parts-by...l-instrumentation/temperature-indicators.html
You stick one on in the area you are interested in. It stays at the maximum temperature seen, so you only need to replace it if it exceeds at temperature you are happy with.
It doesn't matter if you forget to read it and go back later, the max temp seen will always be there until it is exceeded
They come in a number of ranges, so may sure that you buy the right set
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Rigger Mortice
N/A
And another thought........
You can get digital thermometers that will trigger an alarm once you reach a preset temperature.
Cheaper than a laser one too.
SteveTibbetts
New member
I use a laser thermometer sometimes at work (tyre tread temperatures) the one I use cost about £8 from Amazon and is just like the one pictured. Works just as well as the expensive versions. The laser itself doesn't actually have anything to with the temperature readings though. Useful as a technical looking bit to impress an audience though - they like a bit of science
JumbleDuck
Well-known member
Thanks for all the responses. I don't want a permanent thermometer - just the ability to make a couple of checks the first time I motor any distance. Access is very awkward, so something I can use at a range of about three feet over the top of the engine would be ideal. I know the laser is a sighting gadget!
Rigger Mortice
N/A
From three feet away it will be next to useless.
JumbleDuck
Well-known member
Ah, right. That might knock the idea on the head. What sort of range could I usefully expect? I don't need great accuracy, just the ability to tell whether the stuffing gland is getting unreasonably hot.
sailorman
Well-known member
Why do you need to constantly need to check this ??????????
JumbleDuck
Well-known member
I don't. I want to check it a couple of times, that's all. The yard have just tightened it up but though the shaft turns freely, they weren't able to get the recommended one drip every twenty seconds. They've recommended that I keep an eye on the gland temperature for the first couple of hours of motoring, and by far the easiest way would be to point something at it. In fact, that's probably the only practical way, as access is very, very limited.
PlankWalker
Active member
I bought one from an outfit in Portsmouth for £7 + battery, to do exactly the same as you, works fine at about 2ft from stuffing box.
Rigger Mortice
N/A
Look at the "DS" ratio (distance:spot). This one http://www.maplin.co.uk/p/infrared-thermometer-with-laser-targeting-n92fx has a DS ratio of 8:1. At a distance of 8" it will measure a spot of 1" diameter. So, at 3ft you would be measuring 4.5" diameter. Heaven knows what the effect of a round target would be but I would expect that you would need to be getting a fair bit closer to get a meaningful reading. I'm sure that you can get them with higher ratios though...the Maplin one was the first I found.
That's why I was suggesting the digital one. You can get them for just a few beer tokens, but I don't know if you could find a way to reach the gland so that you could stick the sensor on.
sailorman
Well-known member
mine doesnt get "HOT" & doesnt drip. or spew out grease i installed the shaft 10 yrs ago
JumbleDuck
Well-known member
Ta. With a bit of contortion I can probably get that far away.
I couldn't. I am not wholly impractical - I have changed the clutch on a Citroen DS singlehanded - but I am a largish chap, in all directions, and there is only about 8" clearance over the top of the engine en route to the shaft, which is why I paid the yard to do the adjustment. I don't know if they have a supply of skinny technicians or just a big tub of vaseline, but they managed ... just!
Mine has given no problems in the five years I've had the boat. As I said, I just want to do a couple of checks in the first few hours of motoring, after which the thermometer will come back to my workshop. It's not greased, by the way.
savageseadog
Well-known member
A thermal imaging camera would be easier to use and generally more effective and modern ones can give a spot reading (I have one), normally expensive, there are some cheap ones to be had on ebay etc but if you have another use for one.................
