As you are probaly aware the factory branded dew shields and Dew Heaters are very expensive for what you get...most serious astronomers build their own......
Any tips on what to use and how to build both of these product....I have already spoken to Westsky who builds his own but what does everyone else use or have built?
Nichrome wire or a string of power resistors and some method of controlling the current flow is all that is required. There are quite a few DIY web pages out there if you are handy with a soldering iron:
Like Vermin says, nichrome, and contrary to what he says an electrical dunce like me can (has) done it. I simply sourced a suitable gauge of wire, and at a suitable length to go with the power supply I use (12 volts). In most I make it a semi permenant fixture, by sheathing the nichrome, and attaching it with electrical tape, in a neat fashion. Wires leading from the nichrome to the other heaters all finish at a plug, and this gets fed to 12 volts. The only trick is the right length/gauge to allow a warming, and alo the fact that you can't solder Nichrome, bummer.
Gary
I have finished my first attempt at a dew shield.....I rung up my trusty people at Dyman Foams and they sell matt black close cell foam in sheets 2 x 1 meter 1 cm thick.....$17...then I went to Bunnings and got some heavy duty Velcro for $8....with this amount of foam I can make 3 dew shields......not bad for about $10 total each......
Total weight is feather like....
Funny that Clark rubber wanted to charge me $55 for a piece 1 x 1 meter for the same stuff..........talk about mark-up......grrrrr
Anyway here is my first attempt.....positive and negative comments welcomed.
Hey Striker,
I'm currently having a dew shield made by a local engineering shop,it will be made of stainless steel with three attaching thumb screws so they will look pretty much like the originals, i'm going to paint it Meade blue which l have already matched.
Once it's done l'll post some pics, if anyone's interested l can get some more done they estimated a price of about $100 ready to prime and paint, not bad compared to Meades $450 or thereabouts.
Mick
The stainless steel is only 0.6 mm thick so therefore it is fairly light but also very rigid it will also act towards being a balance for any accessories mounted at the viewing end. Mine is being made 400mm long but can be made to owners requirments.
Mick.
Nice shiled(s) Tony, I too have used this sort of material, and an added bonus is the fact that it keeps your "soon to be made" dew heaters heat in. Makes it more effective.
Gary
P.S, As Robby for a picture of his C8 dew shield, it shows how old he is, psycodelic (is that how you spell it).
Haha Robby......nice colour scheme.....but wouldn't those bright interior colors reflect some light........dont you want it to be a matt black interior.?
heyyyy....STRIKER !!!! thats a great dewshield you've made there!!!!...I remember going to a telescope store & they wanted over 100 bucks for a dew shield..!!! I was like WHOA !!! forget that noise !!!!....so , I went out and got some insulation stuff at a hardware store and lined it with a felt-like material...I agree that a LIGHTWEIGHT dewshield is far better than some heavy thing that will just cause the scope to take a NOSEDIVE !!!!...here is a pic of the one I've made for my 12 " GSO scope.....cheers !!!!
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Markus
12" GSO SCOPE
There is a US based company called Astrozap that makes both the flexible foam and rigid metal dew shields. The metal ones are available in colors to match your scope. Recently they have introduced a flexible model, similat to that shown as the "Striker Shield", with built in dew heater. They call it the "Flexi-Heat" dew shield. It sells for $74.95 US in the eight-inch size, $85.95 in 9.25 inch, $92.50 for the ten-inch, etc. The problem as you might imagine is that these ship in fairly large boxes, so the shipping charges to Oz could be a real killer.
Hey Starkler !!!!.....this dewshield is held on simply by using "VELCRO" on the bottom. I stretched it around the tube as tight as I could , then I made a line with a marker and I put velcro with adhesive to hold it in place....LMAO!!!my neighbour used to see me setting up in the yard and she said " oh hes getting ready on his launching pad", then I invited her & her husband over for a peek at jupiter because they didn't believe it was a telescope !!!!!....HAHAHAHAHAH
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MARKUS
12" GSO SCOPE