They look pretty darn good. How high to the fins have to be to minimise vibration, and with a permanent pier do you recommend customers to fill the shaft of their pier with oil, sand or cement to even further dampen vibration and improve stability?
G'day there,
On the 150 dia pier, the top gussetts measure 32x128x6mm, bottom 50x200x6mm. The 190 dia pier has all gussetts 50x200x6mm. These figure may change as the product is still evolving, but hopefully should be sufficient to help minimise vibration and give the pier structural integrity and good weight bearing characteristics.
As for filling the piers, I would recommend either washed river sand, cement or fine granulated rubber as the best materials to use as a vibration dampening medium.
Steve Bain
Southern Cross Piers
very nice piers you have there. great engineering work. im for one hate carrying my equipment then packing it up at the end of the night. will the pier fit an EQ6 mount? The pier looks abit too low next to you or maybe you are just tall
I just added four brackets to my pier and its now as stable as a rock. I super sized it - and went for four fins 1.1 metres by 15cm by 1cm width. The pier looks alot like the tail end of a 2,000lb bomb, and my friend who did the welding said eveyone who saw him drive down the street with it upright in his ute gave him a what the ... heck look
G'day once again Guys,
Just a couple more pics showing details of pier with EQ6 adapter plate for Houghy.
Astrojunk, thanks for your kind words. As I hope you can see in these pics, I reckon they are looking even better now that they are finished in hammertone powder coating instead of just being spray-painted.
Cheers,
Steve Bain
The three stainless steel bolts on the adapter plate are each 12mm thick and have a tensile strength rating of at least 70kg/sqmm. The bolts are 65mm long, and once the securing nuts and washers are fixed there will only be a maximum of 10mm of exposed thread per bolt, even less if level is acheived with minimal adjustment. The bolts are also threaded through the top plate of the pier to minimise any potential movement. The top and adapter plates are 10mm thick aluminium sheet cut to a diameter of 215mm, with the bolt holes drilled at approx 90mm radius in each. Assuming a load of around 30kg (scope and mount) being placed at the center point of the plate, I am sure any potential flexure of the plate would more than likely be of little or no consequence. In fact, when you think about it, the only forces in play should be the movement of the scope around the RA/DEC axes of the mount, with perhaps a minor amount of torque force from the mount motors being transferred to the pier during acceleration/decceleration of motors, but not neccessarily during normal tracking.
Hope I haven't rambled on too much.
Cheers,
Steve Bain
The three stainless steel bolts on the adapter plate are each 12mm thick and have a tensile strength rating of at least 70kg/sqmm. The bolts are 65mm long, and once the securing nuts and washers are fixed there will only be a maximum of 10mm of exposed thread per bolt, even less if level is acheived with minimal adjustment. The bolts are also threaded through the top plate of the pier to minimise any potential movement. The top and adapter plates are 10mm thick aluminium sheet cut to a diameter of 215mm, with the bolt holes drilled at approx 90mm radius in each. Assuming a load of around 30kg (scope and mount) being placed at the center point of the plate, I am sure any potential flexure of the plate would more than likely be of little or no consequence. In fact, when you think about it, the only forces in play should be the movement of the scope around the RA/DEC axes of the mount, with perhaps a minor amount of torque force from the mount motors being transferred to the pier during acceleration/decceleration of motors, but not neccessarily during normal tracking.
Hope I haven't rambled on too much.
Cheers,
Steve Bain
ok 20kg counter weights, eq6 mount and an 18kg 12" meade OTA and 1.5 kg for the lumicon giant easyguider. hope that doesn't flex!
It wasn't carrying capacity that I felt could be honed, it was each bolt say carrying a 10kg load on a 12 mm outside thread stainless steel. I pondered would you have noticeably less vibration (considering both sideways sheer or flex and sideways sway) from a bolt say in the 12mm to 18mm diameter range - or is this totally not a problem anyway?
Of course if you go for six over-sized bolts rather than three bolts you will totally kill any exposure for sway - if there even is any in the first place, for a extra cost under $10 maybe?
well, s'pose it wouldn't hurt to give it a try sometime, at least. Gonna have to have a look around now for some measuring instruments to do some tests on the piers.
I just wanna pop in and say that I made my own pier (with the help of a steel factory of course ) and it was about $300. Here's some pictures including a plan: http://www.flickr.com/photos/siovene...7625165411361/
