21 replies to this topic

[N1ghtSc0p3]

After reading up about the Todmorden piers, I decided that something like that would definitely make imaging a little easier, especially if I can leave the mount out full-time (covered, of course). So this past week I set about procuring the materials, and then spent this weekend putting it all together. I ended up putting half a cinder block in the footer, since I bought one in case I wanted the pier higher than ~32". I used about 125lbs of instant-set concrete, and a 16" square, 2" thick paver, with the base and two cinderblocks tied together via J-bolts and 1/2" stainless bolts.

 

 

Footer hole dug, with 2" of gravel for drainage in the bottom.

 

I used a transfer punch to mark the locations of the holes.

[N1ghtSc0p3]

Here's the half-cinderblock:

 

The anchor bolts being held in position for the concrete to cure.

[N1ghtSc0p3]

Anchor bolts in position

 

Base plate (paver) leveled and in place

[N1ghtSc0p3]

I forgot to take pics as I placed the cinder blocks in place with the construction adhesive and bolts, but the top of the top block ended up pretty level:

 

 

And here's the result at the end of yesterday, after about 5 hours of work.

 

[N1ghtSc0p3]

So one of the problems I ran into was the stainless bolts I bought to mount the plate did not have a consistent head circumference. The one that I tried at the store fit in the recessed hole in the plate, so I assumed they'd all fit. Not so much...2 of the 3 wouldn't drop down into the recess. Fortunately I have a lathe, and was able to turn down the bolt heads just a few thousandths to fit.

 

 

 

Here's the general arrangement of the bolts, with the plate turned upside down. The fender washers will sandwich the top of the top cinderblock.

 

Edited by N1ghtSc0p3, 27 September 2020 - 02:35 PM.

[N1ghtSc0p3]

Here's the leveling mechanism, with the top nuts in this picture securing the plate to the bolts, and the bottom nut/washer combo used to level the plate.

 

 

Here's the underside of the cinderblock top, with the fender washer/washer/lock washer/nut combo.

 

 

Here's the level in N-S:

 

 

And the level in E-W:

 

 

[N1ghtSc0p3]

And here's the completed pier with the plate mounted, leveled, and aligned. When I set up my MYT last weekend, I made note of the N-S orientation (354 degrees) and aligned the plate to the pier with the same measurement. That's why it looks a little off-kilter. The MYT has some azimuth adjustability, so I don't need to be spot on, and I think I'm within a degree of 354.

 

 

I'm hoping to get out tonight, if the weather cooperates, and do a calibration run to polar align the mount. Then I plan on leaving the mount out and covered, so I only need to add the scope/camera, connect the computer, power up, and start imaging. I figure this will ease my setup time by ~80% over using the tripod.

Edited by N1ghtSc0p3, 27 September 2020 - 02:37 PM.

[ldcarson]

Thanks for the pics and write up.  This is on my list of things to do when I get back home to Texas.

[N1ghtSc0p3]

Sure thing, stay safe down there!!

[N1ghtSc0p3]

Just a quick update. So far this has been nothing short of transformational for my imaging. Not necessarily the quality of images that I produce, [I'm still a total newb on processing!!!] but more on the ability to get out for a quick photon collection party. Last night the forecast was good up until about midnight, and with a new toolbox setup with all the imaging control stuff inside, and only a handful of cables to plug in, I was up and running in under 3 minutes. Then shutting everything down took less than 7 minutes around midnight when the humidity cranked up and some high clouds rolled in. I got 3 hrs of subs in, and it took up ~25 mins of my time total, including setup, teardown, building the sequence in TheSkyX, and running an AutoFocus routine after an hour's worth of subs.

 

If anyone is on the fence about doing one of these little piers, get off said fence and do it! 

[mikenoname]

Couldn't agree more. Mine is a simpler version, but still gives me the ability to leave the wedge outside permanently polar aligned which saves a ton of time at setup!

 

 

Attached Thumbnails

• 

[N1ghtSc0p3]

Totally agree Mike...its all about the time saved. I love your setup...another 'quick n dirty'...what did you use for adhesive between the blocks? I'm also really intrigued by the plywood wedge...how's that working out for you? 

 

And completely jealous of your Bortle skies. I'm on the edge between orange & red. 

[mikenoname]

I just used a tube of construction adhesive from the local big-box hardware store, nothing special. The cinderblocks were construction scrap collected by my pack rat landlord, so they were just hanging around for free already.

 

The plywood wedge was something I built a couple of years ago for an ETX-70, a much lighter scope. But, my dad always taught me to overbuild everything and so I made this out of three-quarter inch cabinet grade plywood and hardware that was well more than enough for the job for that little Meade telescope.

 

Fast forward to now, I had the Evolution mount and the six-inch imaging Newtonian that I wanted to try on a cinderblock pier. I figured I wanted to make a bigger wedge than the one I used for the ETX-70, but in the meantime, I thought that little wedge would be good enough to at least be a proof of concept for the larger rig. Turns out that it worked, and continues to work, so well that I don't think I'm ever going to build that larger wedge. I carefully polar aligned it two months ago and have done at least two dozen sessions on it since (including a number of them live streamed – see the live streams thread in the EAA section here on Cloudy Nights) and it is just rock solid.

 

I will probably get out there at some point during the next couple of weeks when the moon is in the sky and I normally do maintenance type things anyway, and check the polar alignment using the SharpCap polar alignment tool. I don't expect to see that it has changed much, if at all in that time.

 

It's working far better than I even hoped!

 

And if there is any threat of liquid sunshine coming my way, I just bungee cord a trash bag over the top and it's all good. Simple and easy.

[CCD-Freak]

A buddy and I are buying some land under Bortle 2 sky (SQM 21.99) about 200 miles west of Dallas / Ft Worth, TX and the first thing I plan to do is install a couple Todmorden piers so I can enjoy imaging as I develop the site.  One will hold a fork mount I have set up for wide field imaging and the other will be for my Ultima 8.  When I build an observatory for my larger mounts I will probably pour a concrete pier but I am considering possibly using a Todmorden.

 

John Love
CCD-Freak

WD5IKX

[Bob_Stan]

This is just an uniformed question - why bother with leveling bolts? A good polar alignment does not depend on the base being level, it is just that being level makes the alignment process easier.  But on a pier you will only be aligning once. It seems the rigidity of the mount now depends on the strength of the three bolts.

[archer1960]

This is just an uniformed question - why bother with leveling bolts? A good polar alignment does not depend on the base being level, it is just that being level makes the alignment process easier.  But on a pier you will only be aligning once. It seems the rigidity of the mount now depends on the strength of the three bolts.

I have wondered the same thing, but one thing the bolts do for you is make the plate removable if you ever need to change it out. Of course, you could also add more bolts (5, for example) and stiffen it up quite a bit, though you then need to be careful to get the bolts all at a consistent height so you don't warp the plate.

[Lola Bruce]

Six jaw scrolling chuck. I thought I was the only one anal enough to have one.

[archer1960]

And here's the completed pier with the plate mounted, leveled, and aligned. When I set up my MYT last weekend, I made note of the N-S orientation (354 degrees) and aligned the plate to the pier with the same measurement. That's why it looks a little off-kilter. The MYT has some azimuth adjustability, so I don't need to be spot on, and I think I'm within a degree of 354.

 

IMG_7573.jpg

 

I'm hoping to get out tonight, if the weather cooperates, and do a calibration run to polar align the mount. Then I plan on leaving the mount out and covered, so I only need to add the scope/camera, connect the computer, power up, and start imaging. I figure this will ease my setup time by ~80% over using the tripod.

Did you use bolts to hold the above-ground cinder blocks together (in addition to the adhesive)? Or are the only bolts the j-bolts at the bottom, and the standard ones at the top to hold the plate?

[speedster]

Gluing the blocks together is asking a lot of construction adhesive.  Thermal cycling, water saturation of the block, accelerated brittleness, etc. - it's going to fail.  It's just a question of when.  A bolt would at least let me sleep at night.  Even better, use thin-set mortar.  Same thermal expansion, not harmed by water, and the block will break before the bond breaks. 

[N1ghtSc0p3]

This is just an uniformed question - why bother with leveling bolts? A good polar alignment does not depend on the base being level, it is just that being level makes the alignment process easier.  But on a pier you will only be aligning once. It seems the rigidity of the mount now depends on the strength of the three bolts.

So the primary reason is because the adapter plate for my MYT...if you look at the plate's outer holes, those are where the mount mates with the plate...its bigger than the top of the cinderblock. Since I had to use bolts to mount the plate, I figured I might as well make it level. The MYT tripod has little levels on it so you can make the top plate as level as possible. I'm not using a machinists level or anything like that. I'm sure there is some error in the plate, but as you mentioned, TheSkyX TPoint calibration + ProTrack results in good tracking. 

[N1ghtSc0p3]

Gluing the blocks together is asking a lot of construction adhesive.  Thermal cycling, water saturation of the block, accelerated brittleness, etc. - it's going to fail.  It's just a question of when.  A bolt would at least let me sleep at night.  Even better, use thin-set mortar.  Same thermal expansion, not harmed by water, and the block will break before the bond breaks. 

So all blocks are mechanically joined with bolts, either J- or regular. I don't trust construction adhesive on its own, either. Also, please keep in mind that this is not a permanent solution -- i.e. I don't envision this lasting more than 5-7 years. This was mostly an exercise in getting a cheap, quick, "good enough" solution up to try out the situation having the mount set up semi-permanently. So far it has been a rousing success, as I've had a couple of 3-4 hour sessions, with minimal setup/teardown time. I hope to post some images that I've gotten as a result of this endeavor to this thread soon. 

 

Cheers!

[N1ghtSc0p3]

Six jaw scrolling chuck. I thought I was the only one anal enough to have one.

Yeah, I got lucky when I purchased the lathe; it came with the Buck 6-jaw, a nice, British 4-jaw independent, and some basic tooling to get me started. The Buck chuck was about 40% of the total purchase price, and its a beast.