What do I need one of these for?

If you have ever been frustrated by trying to find an astro target using the typical optical finder that comes with most scopes, you will be pleasantly surprised at how simple a red dot finder can make that task. These finders project a red dot on an optical window, that when sighted through, seem to place that dot in the sky. Instead of a magnified, reversed and narrow field of view you typically get with an optical finder, you see the entire sky, unmagnified and un-reversed. Using this finder is as simple as placing a red dot on object that you want to view and you are ready to go.

This idea was first used as a sight for firearms, but the astro community quickly saw the potential of these devices for aiming scopes and adopted them.  There are many Astro-Related companies selling a version of this idea, but often they carry a pretty high price tag, anywhere from $25 to $50 and more.  This project will describe how you can put together your own for around $10.

Daisy, Daisy, give me the altitude....

The main component of our finder is known as a Daisy Electronic Point Sight.  It is widely sold through sporting goods stores and big discount stores.  They typically sell for less than $10 - I found mine for $6.99. Once you have the Daisy, you have half of the solution, we still need a way to mount this sight to the scope.

The Kit

As you can see, the components are pretty simple - a couple of binder clips, two 3" number 10 stove bolts, some matching nuts and lock washers and a small block of metal known as a "machine key" - all available at a decently stocked hardware store. In the event that you cannot find the machine key, a small block of hardwood, or other similarly shaped material will work just as well.

To put the mount together, you start by drilling 2 holes in both binder clips along the top side - evenly spaced, down the center line, just large enough for the bolt to slip through. You can make drilling the holes easier by clamping the clip on a narrow piece of 1/2" plywood or wood stock while doing the drilling.

Now take your stove bolts and a nut for each. Thread the nut all the way to the head and then squeeze open the binder clip and insert the bolt through bottom side of the hole. When you are done, the head of the bolt should be inside the clip.

Now take a lock washer and another nut and run those down the bolt and tighten firmly against the binder clip.

With another nut for each bolt, thread it down just far enough to allow the end of the bolt to pass through the other binder clip and have just enough bolt exposed to start another nut. Add that nut and tighten them tightly against both sides of the binder clip.

Take some time to make sure that all of the nuts are tight - doing that will prevent the mount from twisting, introducing the possibility of errors in pointing.

Now we take the Daisy sight and remove the two screws that attach the dovetail clamp to the unit and remove them- we will not be using the dovetail clamp or the screws.

You can now attach Daisy sight by squeezing the binder clip and sliding the bottom portion of the sight into the clamp.

Mount Up

Mounting this to the scope is where the "machine key" comes in. Simply apply a strip of double sided tape to the bottom of the key and, taking care to insure that it is lined up well with the centerline of the tube, press it into place. To mount the finder, you clamp the bottom clamp to the block, ensuring that the lips of the clamp are firmly down against the tube. By making sure it is seated on the tube you provide a reasonable degree of repeatability.

Conclusion

For those concerned with having the flashiest gadgets out there, this little idea probably falls short. However, for situations where you need an inexpensive and easy way to add a red dot finder, this is a great solution. Club scopes, Kid's Scopes, Grab and Go's, anywhere that cheap and easy is the idea.

Here's what I like about it:

Total cost including the Daisy sight - less than $9.

The assembly is easily mounted and removed in just seconds.

The height provided by the 3" bolts moves the finder off of the tube to a position that is much easier to view through than if it was attached directly to the tube.

It does provide good repeatability - at least on par with the Rigel Qwikfinder I use on one of my scopes, it takes just a small tweak to zero it in upon reinstalling it on the scope.

It is reasonably light weight.

The mount does not mar the scope - no holes.

 

If you wanted to "dress things up a bit" you could always spray the entire thing black.  Maybe some heat shrink tubing over the bolt shafts.  Once you mounted the Daisy, you could even remove the arms from the top binder clip (although I might throw them in my eyepiece case just in case I needed them sometime).

If you have been thinking about adding a red dot finder to your scope, or if you would like to help a beginner or child have a whole lot more fun with their scope - make them a gift of one of these finders and mounts. They will always be grateful, and you can't get much better return than that on a $10 investment.

rnabholz@yahoo.com

 ©2007 Rod Nabholz

Twin Tube Telescope * Manual Dob Setting Circles * Binocular Chair
Kid Peek Telescope* Downward Looking Binocular Mount * Easy Alt/Az Mount Mod
Barn Door Mount * Observing Stool * Cheap and Simple Red Dot Finder Mount
PST Eyepiece Shield * Eyepiece Case * Key Reel Red Light Keeper
 Kid Peek II * Observation Log and Sketching Forms *  Telrad Dew Shield 
Telescope Mounted Green Laser  *  Observer's Eyepiece Bag
Vintage Telescope Restoration  Towa 339 "Katana"  *   DIY SCT and Mak Cooler

 

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