Telrad that won't stay put...

[Mr Spock]

I have a Telrad on my 12". It keeps falling off.

I've tried new sticky things, glue, even Velcro (which worked but was wobbly). Short of drilling it and putting bolts through, I can't think of a solution. 

Any ideas?

[M40]

I've found the sticky pads for car rear view mirrors work well for most things, particularly the 3m ones. Clean the surface first though. All the best 

[Ratlet]

How is it falling off?  I found with my quickfinder it stuck to the dob fine, but it wouldn't stick to the plastic.  If you aren't using the findershoe, or have a spare one on the dob I can print you up an adapter for it.

https://www.printables.com/model/55851-telrad-dovetail-mount

Or I could do something like this:

https://www.printables.com/model/116497-telrad-reflex-sight-mount-for-telescopes

And you could use straps to hold it on.  Or I could give it a larger surface area where it meets the mount so it will stick better.

[PeterStudz]

Personally I’m not a fan of sticking/glueing things onto a telescope - never got it to work well enough. I’m more happy with getting a power tool out and drilling some holes.

Edited April 1 by PeterStudz

[Paz]

When I used to have a telrad on my ST120 I wrapped a couple of zip ties around the ota and over the tetrad base, and had a bit of sleeping bag roll mat under the base and zip ties to protect the ota. This held the base down firmly enough and was reversible without damaging the ota.

This is a much smaller scope, but some of the principles might translate to a big Dob.

[Mr Spock]

Ties won't work on my 12". I'm thinking either drilling the Telrad and tube, or fitting another finder shoe and using my Baader which is a lot smaller.

[Ricochet]

As the tube is rolled steel perhaps some magnets could be epoxied to the bottom of the Telrad base to help it stay put. However, from memory the Telrad base has a V-block profile to allow it to be used with a variety of different sized scopes. With a 12" dob the arc of the tube under the Telrad base will be relatively flat so perhaps the problem with the original/replacement sticky pads is that there is only a very slim area of contact along each edge of the base. In this case you could potentially make some sort of adaptor or fill some of the space under the base to create a larger contact patch for the sticky pads to stick to.

[Louis D]

36 minutes ago, Mr Spock said:

Ties won't work on my 12".

Why not?  Is it just the roughly 3 foot circumference?  I've daisy chained a dozen or more zip ties end to end to go around very large items successfully.

[wookie1965]

I use this my Telrads have not fell off 

https://www.amazon.co.uk/Mammoth-Powerful-Grip-Tape-double-sided/dp/B0038LUASA?th=1

[Spile]

I can recommend adapting it for a dual dovetail…

[Highburymark]

Here’s my bizarre solution, which works surprisingly well. I can’t remember how I sourced the parts to adapt it to a normal finder shoe, but I’m sure they are still available.

[Mr Spock]

Solved the problem - switched to a Baader like I have on the Tak.

A lot less bulk and does what I need it to - point!