Artimes
Active Member
I have a NASA Target masthead unit that has lost its "cups" Can this be repaired at the masthead, are parts available, can they be fabricated, can cable be disconnected at masthead...thanks
WIN SPEED INSTRUMENTS REPAIR
- Thread starter Artimes
- Start date
Shanty
Well-Known Member
NASA will sell you a replacement set of cups for a reasonable sum. Fitting them at the masthead would be feasible, but not easy, as there are several small components involved - depends on how comfortable you are with working at the masthead.
The cable is wired in to the masthead unit - the cable ends are soldered to a circuit board within the unit - not really a masthead job - I've tried.
The cable is wired in to the masthead unit - the cable ends are soldered to a circuit board within the unit - not really a masthead job - I've tried.
Twister_Ken
Well-Known Member
Nasa really should do something about its biodegradable masthead unit.
Bodach na mara
Well-Known Member
Could I use this thread to ask if there are any reliable wind instruments (preferably at a reasonable price.) I ask because my own is Autonic and ancient and needs replaced. The masthead sensor usually lasts only a few seasons before the bearings develop so much resistance that it takes a good force 2 to get it to start turning at all. I have had good service getting them replaced, but I wish I didn't need to.
rwakeham
Well-Known Member
I have been through two sets of Nasa cups. Generally I find their equipment ok, but I have replaced it with a Raymarine ST60. Fitting it was fairly easy.
Twister_Ken
Well-Known Member
My Raymarine (actually Autohelm) stuff has been up there a long time and still does the trick.
ShipsWoofy
Well-Known Member
<u>Refurbish and modify a nasa wind masthead</u>
Due to losing the pin on my nasa masthead unit I was left with two choices, send my crew up to attempt to glue a new pin in place and face the possibility of not getting it straight or losing another set of cups, this was the second time we had lost cups. I fancied, rather than just replacing the pin, replace the whole base unit which uses a better M2 nyloc nut to hold the cups in place.
I called nasa who sold me a base unit for £10.00. This was great. I am far more confident that the newer method with a thread and nut is superior to the spring clip arrangement they did employ.
I also wanted to make the head unit easier to repair, so have modified it to include a plug and socket at the masthead, this means my crew just has to unscrew four screws and the connector to bring the whole unit down, to be worked on in comfort.
Part One – Replacing the base unit
When you unscrew the seven nuts and bolts which clamp the head unit together it splits as below> This is actually the new base before I put it back together, hence the silicone grease added to keep water out. It was bone dry when I separated initially
We need to unscrew the circuit board from the base unit, this is held down by three self tapping Phillips screws.
It is then necessary to unsolder the five wires from the stands on the edge of the circuit board, make a note of the order of these wires before removing. Removal is best using solder wick or a solder pump.
You should now be left with the wires free of the circuit board, gently extract them by pulling on the cable from the bottom of the pole, you will of course need to loosen off the plastic nut which forms a cable clamp. Retain this nut as the replacement head unit does not come with a clamping nut, best leave it on the cable.
You now need to gently push the cable back up the tube of the new base unit, this may require a little wiggling over the kink in the pipe. Once through solder the wires back in place using the removal guide you wrote out earlier. Now you screw the circuit board back down and close the case using the seven nuts and bolts. Note I have painted the case and joints in silicon grease to maintain waterproofing.
Part Two – Modifying - This of course is personal choice, just added to give ideas.
I decided to add an in-line plug and socket at the masthead, this was purchased from Maplin, I have chosen a screw locking type, it actually sits under the mast cover up top to keep the weather off, but you could use a tie-wrapped rubber boot to keep it dry if you chose to leave it outside.
The connectors had 8 pins, I only needed 5 which is not a problem. You may find a 5 pin plug and socket, but I would advise against the din type nasa use as there is no way to lock them together up top.
Here I have stripped back the outer insulation. The four wires were stripped back and tinned. A fifth wire (grey) was soldered to the screen (braid) to enable me to ensure the screen connection remained unbroken by connecting it through one of the pins.
The plug clamp also clamps down onto the screen, this should stop the connector creating any noise onto the signal wires within the screen. Note. I have also cut ready the heat-shrink pieces to seal the joints to the pins. These should be removed when you start soldering, just adding them to each wire in turn, otherwise the soldering iron will shrink all of them before you have a chance to pull them over the joints. Sealing could also be done satisfactorily with Vaseline or silicone grease.
The plug soldered up and ready to be closed up.
A similar method is used to connect the socket, ensure you write out your pin-outs carefully and if blue is on pin 1 then it should also be on pin 1 of the socket, it is easy to get them back to front, check and check again, the plug and sockets have pin numbers on the back, follow them!
The re-assembled masthead unit, without and with wind-cups and my new in-line masthead connector to allow the unit to be brought down for future repair.
Hope this helps a little.
J
It is probable if you have an older masthead unit you do not have the M2 threaded pin but just a plain pin which uses a spring clip to hold the cups in place. This can be replaced at the masthead but is fiddly. Prior to this repair my crew fitted new cups up the mast, but I fear she may have weakened the pin working up the mast as within a couple of months we had lost the replacement cups and the pin which is known to fall out. A replacement pin can be sourced from nasa but when I tried they had none in stock. They were happy to sell me the new bottom unit with the screw fitting which you see above, it gives me far more confidence.
The pin just fits into a hole in the base unit, it would be easy to glue a new one up the mast as the hole is deep enough to keep the pin aligned. Most people use araldite for this job, but as the base unit was £10 I was happier to go that way.
New cups are available from allgadgets windcups.
J
Due to losing the pin on my nasa masthead unit I was left with two choices, send my crew up to attempt to glue a new pin in place and face the possibility of not getting it straight or losing another set of cups, this was the second time we had lost cups. I fancied, rather than just replacing the pin, replace the whole base unit which uses a better M2 nyloc nut to hold the cups in place.
I called nasa who sold me a base unit for £10.00. This was great. I am far more confident that the newer method with a thread and nut is superior to the spring clip arrangement they did employ.
I also wanted to make the head unit easier to repair, so have modified it to include a plug and socket at the masthead, this means my crew just has to unscrew four screws and the connector to bring the whole unit down, to be worked on in comfort.
Part One – Replacing the base unit
When you unscrew the seven nuts and bolts which clamp the head unit together it splits as below> This is actually the new base before I put it back together, hence the silicone grease added to keep water out. It was bone dry when I separated initially
We need to unscrew the circuit board from the base unit, this is held down by three self tapping Phillips screws.
It is then necessary to unsolder the five wires from the stands on the edge of the circuit board, make a note of the order of these wires before removing. Removal is best using solder wick or a solder pump.
You should now be left with the wires free of the circuit board, gently extract them by pulling on the cable from the bottom of the pole, you will of course need to loosen off the plastic nut which forms a cable clamp. Retain this nut as the replacement head unit does not come with a clamping nut, best leave it on the cable.
You now need to gently push the cable back up the tube of the new base unit, this may require a little wiggling over the kink in the pipe. Once through solder the wires back in place using the removal guide you wrote out earlier. Now you screw the circuit board back down and close the case using the seven nuts and bolts. Note I have painted the case and joints in silicon grease to maintain waterproofing.
Part Two – Modifying - This of course is personal choice, just added to give ideas.
I decided to add an in-line plug and socket at the masthead, this was purchased from Maplin, I have chosen a screw locking type, it actually sits under the mast cover up top to keep the weather off, but you could use a tie-wrapped rubber boot to keep it dry if you chose to leave it outside.
The connectors had 8 pins, I only needed 5 which is not a problem. You may find a 5 pin plug and socket, but I would advise against the din type nasa use as there is no way to lock them together up top.
Here I have stripped back the outer insulation. The four wires were stripped back and tinned. A fifth wire (grey) was soldered to the screen (braid) to enable me to ensure the screen connection remained unbroken by connecting it through one of the pins.
The plug clamp also clamps down onto the screen, this should stop the connector creating any noise onto the signal wires within the screen. Note. I have also cut ready the heat-shrink pieces to seal the joints to the pins. These should be removed when you start soldering, just adding them to each wire in turn, otherwise the soldering iron will shrink all of them before you have a chance to pull them over the joints. Sealing could also be done satisfactorily with Vaseline or silicone grease.
The plug soldered up and ready to be closed up.
A similar method is used to connect the socket, ensure you write out your pin-outs carefully and if blue is on pin 1 then it should also be on pin 1 of the socket, it is easy to get them back to front, check and check again, the plug and sockets have pin numbers on the back, follow them!
The re-assembled masthead unit, without and with wind-cups and my new in-line masthead connector to allow the unit to be brought down for future repair.
Hope this helps a little.
J
It is probable if you have an older masthead unit you do not have the M2 threaded pin but just a plain pin which uses a spring clip to hold the cups in place. This can be replaced at the masthead but is fiddly. Prior to this repair my crew fitted new cups up the mast, but I fear she may have weakened the pin working up the mast as within a couple of months we had lost the replacement cups and the pin which is known to fall out. A replacement pin can be sourced from nasa but when I tried they had none in stock. They were happy to sell me the new bottom unit with the screw fitting which you see above, it gives me far more confidence.
The pin just fits into a hole in the base unit, it would be easy to glue a new one up the mast as the hole is deep enough to keep the pin aligned. Most people use araldite for this job, but as the base unit was £10 I was happier to go that way.
New cups are available from allgadgets windcups.
J
Artimes
Active Member
Thank you one and all for your valuable advise "to the masthead we will go!"
ak7274
Member
Did mine last week up the mast on Sanda..dead easy job,if it has a nut take up long nosed pliersand keep all washers in your mouth. I put them all on a piece of sellotape and stuck it on my chin so as not to lose them.The nut is the hard bit if you have thick fingers.The clip is easier
smudger_6635
New Member
I have a NASA Clipper wind instrument that has developed a fault which I think is due to a connector problem. It has two connectors, one up at the mast head and one going through the deck. Does anyone know what the signals are that come from the masthead unit? This would allow me to test at deck level and see if the fault is in the through deck connector or if I have to get up the mast.
ShipsWoofy
Well-Known Member
What is the fault?
oldharry
Well-Known Member
Re: WIN SPEED INSTRUMENTS - BIRD ATTACK!
Does anyone know any way of stopping our avian friends from trying to perch on the vane of my NASA wind machine - and breaking it off! At least, I can not think of any other reason for it breaking twice in 6 months. Any ideas?
Also the wind speed indicator is reading low - around 10kts in 15kts of wind.
Does anyone know any way of stopping our avian friends from trying to perch on the vane of my NASA wind machine - and breaking it off! At least, I can not think of any other reason for it breaking twice in 6 months. Any ideas?
Also the wind speed indicator is reading low - around 10kts in 15kts of wind.
smudger_6635
New Member
The fault is that when I switch it on, the wind speed jumps all over the place, from 20 to 2, back to 40 etc. I have set it to average but it made no difference. The direction indicator is stuck on South Easterly. However, when I disconnect the deck plug it reads North Westerly. I have obviously made a mess of the plug connections somewhere because it was working OK when I connected it before I cut the cable to make up the plugs.