Hi, I am hoping i may be able to please get some advice from members who have successfully managed to get insulation material for large diameter scopes like the Celestron C14.
It looks like most people over seas in the US use a material called Reflectix
Basically it is like our silver foil that we use in our roofs and walls, except this stuff it more like a silver foil bubble wrap product.
I have yet to find a place where i can get this stuff locally.
Would simply wrapping the silver foil that we use in the roofs and walls do the same thing, or is there another product out there that people are using?
Well I’m not bold enough to say it’s the best option… but I’ve got my c14 wrapped in heat/sound insulating foam they use for cars. I got it off eBay and it similar to this stuff:
It a cheaper and I reckon would give better insulation than the reflectix imho. It sticks on so it’s more of a permanent solution and if I ever choose to take it off it’s going to cause a terrible mess- but it seems to work well flattening out the temperature drops (still need to adjust focus every hour for dso imaging) and reduces heat gradients. Advantage of it being stuck in is that it acts as a vibration dampener and it was really easy to cut to size. I never need to adjust it and it’s really heavy duty. It’s not particularly pretty, but I really don’t care - I don’t think anyone buys a c14 cause of its looks!!
Note that a good dew shield and dew heater are still absolute necessities even when wrapped. My dew shield extends 550mm and on a very dewy night still can get some condensation if I’m aiming at the meridian.
Thanks for the link, It looks like a good option as well.
I wonder how that would go compared to the Bubble wrap foil?
My thinking is that the air gaps in the bubble wrap would keeps temperatures on the tube a tad more stable,
But open for any opinions or suggestions of course.
I have a dew heater for it + a Velcro type dew shield.
Going to look at adapting some tiny fans in the vent holders also, pretty much the same idea that the Temest Fan uses.
I’d try one step at a time- I’ve heard it said that the fans aren’t necessary if its wrapped so maybe try the wrapping first as it’s a lot cheaper/quicker solution. Also, fans are going to be pumping moist air into the tube so I imagine that could cause issues too?
I’m pretty any insulating wrap would work as they are pretty much all either foam or plastic with closed cell air gaps (obviously the insulation I use consists of billions of much smaller air gaps, but still the same principle). I’ve seen one guys uses yoga mats on his ota with apparent success.
My AP Honders scope came with a wrap around blanket with velcro. Its like wetsuit type material. A bit stretchy and not too heavy.
It seems to work well.
If you really want to try the bubble foil wrap as a dew shield, it is sold in Bunnings but shininess is a problem .
A proprietary clip on dew shield is more secure , enables the bahtinov and you could wrap that with dark Clark closed cell foam and tape or blanket if you like.
I think extending the dew shield is a good thing and a dew band at the corrector end and wrapped around the camera coupling works best with that.
Appreciate the replies and advice.
I will get some of either the wetsuit material or that car insulation foam.
Best to go with something that is tried and tested.
Appreciated.
I used this for my old 10" which was terribly dinged (Beyond the panelbeater's ability) but perfectly usable. It was first intended for cosmetic reasons, but has the added advantage of reducing dewing due to rapid temp loss/variation. Zip ties to affix to OTA. Have also used it on a couple of old Mak's since.
Also available in gold, and only has 2mm of tight cell foam - just enough/not too thick. It's super light as well. Used by aeromodellers for "wing bags" to protect during transport.
You can also cut the foam to shape a "scope cover" to protect when on mount also, just determine your shape, and no sewing! A hot iron carefully run around the edge "welds" the seam shut and gives a good professional finish.
I used something similar to this for my C11.
It is very effective as dew shield and stiff enough to hold shape.
I painted it black (originally, foam was dark gray, ~10mm thick) with flat black spray (Bunnings).
One of the little items I've used in the past for a multitude of photographic applications is Cinefoil. It's almost a standard within the film industry, and while a roll of it can set you back a little, it can be re-used over and over again, re-shaped, and it will hold shape. It take a fair amount of use for it to wear through.
Appreciate all the replies and advise, lots of options there to chose from,
I have some 10mm Automotive sound deadener foam coming.
I figured being a tad thicker it would help just that little bit more.
My C14 lives inside at the moment until i build my roll off roof observatory.
I plan to insulate the read end as well and fully block the rear vents.
I also have a dew heater for the corrector plate.
My theory is and could well be wrong, But I figured that the more it is insulated, the less chance it has to get those horrible tube currents especially since it lives inside at the moment.
You could paint your tube in Aerogel bead filled paint which , besides insulating , is hydrophobic and fantastically expensive. You would need a lot of coats. But the paint is lightweight.
Quote:
Originally Posted by mura_gadi
The darker the colour the faster you will get dew, so white exterior if you can.
Remember your also insulating any remaining heat in the tube once in place, only way out now, is to dissipate heat via the ends of the tube...
Ps.
Be interesting to see if anyone has used hydrophobic paints on the dew shields as part of dew control.
Reflectix is just R1.08 insulation - not the 4.8 claimed on some websites.
There are alternatives locally available, usually sold as roof/wall insulation; on my scope I used a piece of Bradford Polyair Performa 4.0 XHD leftover from a reno.
