Last updated: 8 June 2002

Another Homemade Dew Cap

From: (Tony Miles)

I just wanted to drop you a line to say thanks for putting up what has to be in my opinion the best ETX website on the Internet.....

Anyhows, I wanted to share my cheap alternative to a homemade basically is the same as Michel's from Belgium, the one you posted the other day, the only difference is the materials are easier to obtain....

dew cap
This is all the materials I used...two C-clamps, a knife, a ruler, a metal bar, a tube of mutli-purpose bonding cement, and a sheet of "Funky Foam" (available at most hobby or craft shops in thickness' of 1mm-5mm....I chose a 3mm sheet. It costs only 79 cents for 12x18" sheet!)

dew cap
I measured the circumference of my ETX90's OTA to be 13 inches. I cut the foam sheet to 14 inches to make a sheet 12x14". I applied a bead of the bonding cement to each side of the 12" length of the sheet. The each bead needs to be a half-inch wide. I used the metal and C-clamps to hold the dewshield together while the bonding cement dried. Usually an hour or two is sufficient.

dew cap
Once dried you have the finished dewshield of 12 inches in length. I cut mine in two equal lengths of 6 inches each. At 6 inches, the dewshield can be slipped over the OTA to be protect it from scratches when not in use.

Here is the finished product on my ETX90....

dew cap

This can easily be done with an ETX125. I'm sure someone else with a little more creativity and materials could make this dewshield with Velcro attached to the edge of the foam so that it be stored flat in a case when not in use.

Now, if I could only get lucky enough to have a night of clear skies. The skies over Atlanta, GA have been cloudy for the past few weeks it seems.

Take care,
Tony Miles

Subject:	Additional info for homemade dew cap
Sent:	Sunday, June 2, 2002 12:25:13
I would just like to add to the homemade dew cap articles.  I could not
find the "Funky Foam" that Tony Miles mentioned in his article, but I
found a foam just like it at Michaels - The Arts and Crafts Store. 
Since these stores are found throughout the U.S., I thought it might be
useful for others to know.  The foam is called "Flexi-Foam", it measures
12" x 18", it costs 79 cents a sheet, and it is made by Fibre-Craft
Materials Corp (  In addition, the store sells Craft
Foam Glue by Beacon that really bonds the foam well.  I made a dew cap
with these materials yesterday (for ETX-90EC) and it turned out great.

BTW, you have a great site.  Thanks for allowing my input.

Brian Huntsman

Subject:	...and more regarding a dewshield...
Sent:	Wednesday, June 5, 2002 12:25:59
From: (Stan Glaser)
In regard to the latest post from Brian Huntsman and a previous post by
Tony Miles, I too made a dewshield about a year ago out of the same
"Flexi-Foam" material that I purchased at our local Michael's - The Arts
and Crafts Store, and I DID add velcro as Tony had suggested. I hadn't
thought much about the adhesive required when I first started, and I
found it very easy to glue the Flexi-Foam to itself just using regular
contact cement. But gluing the velcro tabs on to the Foam proved harder,
particularly when I tried to remove the shield by undoing the velcro --
basically the velcro tabs just came unglued off of the Foam (boy, velcro
sure holds tight to itself -- no wonder NASA invented the stuff!) I then
tried Elmer's white glue, and that was a little better, but it still
failed. I ended up trying the glue that Brian mentioned, CraftFoam Glue
by Beacon (should have used that from the start!), and so far everything
seems to hold together very well (over a year now), even after numerous
closings and openings when I need to pack the scope away for traveling.
I've attached a couple of quick photos to show the setup. I happened to
have the small square velcro tabs laying around from a previous project,
so I ended up using 5 of them. A long strip would work just as well,
although I think it's easier to undo them when there's that small gap
between each piece.

Stan Glaser
Dew shield Dew shield

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