Mounting Plate 6mm or 8mm

[The Mekon (John Briggs)]

I am looking at making a side by side mounting plate for my AT 106 and the finder. Now that I have sold my AP130, (which needed a tall pier) I find the pier mount too high to use the finder scope when below altitudes of around 30 degrees without a step up. So the plan is to mount the finder beside the scope rather than above it.

Q. Is 6mm aluminium plate sufficiently stiff, or should I go for 8mm?
Am looking at making a plate 200mm x 250mm with a dovetail bar bolted beneath.

Cost is around $25 for the 6mm, $35 for the 8mm.

thanks for any suggestions

[Saturnine (Jeff)]

Hi
I've made a few side by side plates but they are for more weight than you'd be mounting. Mine are 300 x 100 x 10mm and 250 x 80 x 12mm and are for 102mm x f6.5 scope and 80mm x f5 guider and ED80 + 80mm f5 guidescope.
Can't see the harm in going for the 8mm plate just for more rigidity though I don't see the need to have the plate so wide, 100 to 150mm would be plenty.

Clear Skies

Jeff

[The Mekon (John Briggs)]

Thanks Jeff, looks like yours would be a vote for 8mm. The plate is approx. 200mm width to keep the ring spacing at 165mm - though the mount will primarily be an EQ6, I use an older Vixen SPDX at times which fixes this figure.
I already have some 140mm x 6mm aluminium flat bar and it seems pretty stiff, hence my thoughts on using 6mm.

John

[el_draco (Rom)]

You may like to consider future proofing your scope and building a solid SBS to cater for a second OTA. In that case, thicker is better provided the mount can handle the weight.

[nebulosity. (Jo)]

I'd go with the 8mm

Jo