Shadow of the Mountain Observatory

Shadow of the Mountain Observatory - The Build

April 17-18, 2011: Pier Footer

4/16/11: Here's a picture of the unfinished pier my buddy is fabricating for me. It is 5 feet tall made from 10" diameter schedule 40 steel. It weighs in at over 280 lbs! The chore for this weekend is to pour a concrete footer suitable to hold this pier.

4/17/11: Again I had to wait for the April showers to subside; I didn't want to fool around with ready mix concrete in rainy conditions! I had initially estimated the needed concrete at about 31, 80-lb. bags, so this is more than I need. The extra will be used to pour footers for the gantry section later.

4/17/11: Since the location is remote, I had to concern myself with bringing enough water to the site. Each of the Aqua-Tainers (Walmart $11.88) holds a little over 7 gallons. A couple trips to the local river and I was able to fill two 18 gallon tubs. At an estimated gallon and a half per bag of concrete, this should be plenty (I actually used less).

4/17/11: Time to dig that big hole. This was the worse part. The deeper the hole became, the harder it was on my back! Approximate dimensions are 24" x 32" by 36" deep.

4/17/11: That translates into a lot of dirt! That's enough for tonight. Tommorrow I will start mixing and pouring the concrete.

4/18/11: Here the form is in place over the hole. A couple of 1 x 4's are used to hold it in place nice and level. 4' rebar is hammered into the ground for strength. I had initially designed the footer to come to within about 2 inches of the floor, but after seeing the pier I decided to drop it down to about 8 inches. This will hide the gussets below floor level and give it a nice clean look.

4/18/11: There's nothing like doing it the old fashioned way. I had considered renting a mixer, but I wanted to see if this old dog still had it in him. Digging the hole was actually more work, IMHO.

4/18/11: Getting close. About 23 bags, or not quite 1 ton at this point.

4/18/11: A couple of templates were cut out of sheet metal. These correspond to the holes in the bottom of the pier. I sandwiched some scrap wood between these to give it some rigidity and bolted on the J-bolts. These will be plunged into the concrete before it sets and will provide the means for mounting the pier to the concrete.

4/18/11: All done. Final count was 27 1/2 bags or 2200 lbs. It was a bit tedious getting those big bolts down in the concrete. I think it was 10% strength and 90% motivation. Hopefully the bolts will be plum and true enough to fit the pier!

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Shadow of the Mountain Observatory - The Build

April 17-18, 2011: Pier Footer

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