Fixating OTA on top of the mount

[Denys]

Hello my friends,

I apologize in advance for what may be a very stupid question, but I would like to check how you fixate the dovetail that is on the OTA on the top of the mount…

There are two bolts there on the mount (see picture) that I assumed should be used to tight the dovetail in place, but the point of contact between them is rather small and it ended up leaving some marks of the tip of the bolt on the dovetail. Is there a way to prevent this from happening? Maybe using a piece of rubber or plastic to stay between the two metal components and avoid scratches... Do you use something like that?

Thanks!

[dweller25]

Yes, this is what I have done for over 30 years.......

[DaveL59]

The screws will always mark the dovetail on this type of mount unfortunately, you'd have to replace the head with a clamping type to avoid this but is perhaps not worth doing unless it is a problem that bothers you too much.

The risk of inserting something to cushion the bolt end from the dovetail will be ensuring that you have things well clamped so that the dovetail doesn't slip or worse disengage and the OTA falls off the mount. Depending on the scope and accessories you use you may find you need to shift the OTA up/down to maintain balance. A very heavy eyepiece for example could change the OTA balance point. Having a filler piece between the dovetail and securing bolts could complicate that especially in the dark.

Edited November 20, 2020 by DaveL59

[Denys]

Just now, DaveL59 said:

The screws will always mark the dovetail on this type of mount unfortunately

Thanks, this is what I was trying to find: if it was a design problem or if it was me doing something wrong! But you have a good point about using something else in between.

[Neil H]

Bresser dove tail has a small plate on the side of it were the screws hit and this plate has 2 small screws holding it on the dove tail you could do the same to yours so would not damage the dove tail 

[Chefgage]

You fix the dovetail to the mount exactly like you have done. It's just the design of this type of connection. There are different types out there as mentioned but the marks/indents do not hamper it's performance.