Can you use an 8" dew strap on a 5" scope?

[Chris]

Hi, I apologise as this is my second question today, but as I would really like the general consensus on this one I'm going to risk it

Is there any reason why I couldn't use my dew strap from my old 200mm C8 on my new 120mm Apo? I was thinking I could just wrap it round further but as it wouldn't go all the way round twice would any uneven heat be a problem does anyone know?

It would save a bit of money if I can use the one I already have.

Any thoughts, does anyone already do this?

Cheers in advance

Chris

[Space Dragon]

Chris

I use the strap from my 9.25 on my 6" refractor with no problems, I think the output from these things is nowhere near enough to cause tube currents etc, but stand to be corrected.

I'd rather spend money on other astro bits than another ******** dew strap :-)

Cheers

[Stu]

I agree, I use the one from my mak on my 4" with no problems. It is a very gentle heat so I can't see it causing any issues.

Stu

[ollypenrice]

Blimey, we wrap owt around owt here! Just keep the wet off. Get on with it and enjoy!!!

Olly

[Chris]

Thanks all  

You guys have just saved me about 35 quid! Although I've just spent 86 quid at FLO on a focus mask and a 15" ADM Losmandy dovetail

[Macavity]

If you have un-sewing skills (lol) you might try unpicking the "lead" end and have a look inside. 

Some strips seem to contain a "ladder" of flat resistive material encased in insulating plastic.

The ends sealed with insulating tape. I imagine it may be possible to cut the strip to length?

Fewer "rungs" mean fewer "resistors" in parallel? Higher Resistance = Fewer Watts etc. etc.

If you have a multi-meter, you can start by measuring resistances? Do a few calculations? 

I mean... DIY Astronomers have been know to make their OWN strips with resistors / wires.

WARNING: Don't know what you're doing with electrical stuff? (even low voltage) then Desist!

P.S. Here's someone else with an inquiring mind...

http://www.cloudynights.com/ubbarchive/showflat.php/Cat/0/Number/2048746/page/33/view/collapsed/sb/9/o/all/fpart/1

[Chris]

Hi Chris, its good thinking but I will go with the if its not broke dont fix it approach if folk say that it wont matter if I wrap it round 1.5 times. I do like what that guy has done on the link, I think that there might even be a market for that kind of thing? might be good for when simple dessicant just doesn't make the grade