2017-08: SKY HEX

Taken by someone from...Texas.

So a guy I've met from...Texas (the state that steals water from New Mexico)...has a clever observing accessory in the form of a portable building that he constructed that he can tote around with him to his observing sites and star parties. He calls it a Sky Box, and the picture above is of it standing up just fine to a bit of a blow out in...Texas...somewhere.

When you are at the scope two of your enemies -- in addition to snakes, spiders and mosquitos -- are light and a cold breeze. A shelter like this does a good job of minimizing those two. It doesn't do a lot to stop the other three. They are just occupational hazards. There are no snakes, spiders or mosquitos in Antarctica, but the same thing applies down there. Get out of the wind and you will last a lot longer.

I decided to take a stab at something similar, and try not to stab myself in the process.

I don't know for sure, but the official Sky Box seems to be, let's say, about 6' or 7' wide by 12' long. That's a nice size. It is made using metal piping and fittings and it all comes apart for transporting. It seems fairly easy to put up and take down, but that's a lot of parts for me.

There was a company that disappeared around 2012, Dark Sky, Inc., that sold light duty wind and light screens made of PVC pipe that could be connected together to make whatever size and shape of wall you needed. Their idea seemed like a good one, their going out of business notwithstanding, so I decided to try it that way.

My shelter started with a couple of restrictions on the design and construction. I needed something fairly light. I only have a small Toyota Tacoma pickup, and I didn't want this shelter to add too much weight. I'm not at the weight limit or anything, but the automatic transmission already goes a little crazy on the hills around New Mexico when hauling my telescope junk and towing my portable astronomical unit (Aliner trailer). I thought that a metal version of what I wanted would be too heavy.

The other restriction was size. I don't have a lot of space available when I'm fully loaded and heading off into the sunset. I really just need to get a bigger truck, but I have to make due with what I've got.

I guessed that making the thing out of PVC plastic pipe and fittings would keep the weight as low as possible. Since I was going to use plastic pipe I had to keep the size under control, because I didn't want to be able to take the thing apart to individual pipes and fittings. It seemed like it would be a lot of extra work to have to construct and deconstruct it each time I used it. I already had to do that with the mount and scopes. The Dark Sky Panel system was all put together with small self-tapping screws to connect the pipes to the fittings. You could take apart or leave together as much as you wanted. I was afraid that the plastic would crack around the holes, especially if the wind got out of control, so I wanted everything glued together and transported as whole as possible.

The design started with a basic box. For my stuff, and just me using it, I decided that a box about 7' by 7' square would be just right. In the interest of keeping things "up" I immediately started drawing braces that cut across the corners to make things more rigid. That design lasted about a day. One problem was that I can't haul walls that are 7' wide. The bed of my pickup is only 5' wide. That means that the walls would need to be broken into panels, each probably about 3'-4' wide. That would be fine, except eight sections of wall to put up seemed like a bit much, both in numbers, and in how to stack them. You see, all of the telescope stuff goes IN the bed of the pickup. The walls were going to have to be ON the bed of the pickup. You'll see what I mean.

It dawned on me that I was starting with a box and right away cutting off the corners with bars that were only going to get in the way of observing, so I thought why not just start with a box that was more roundish, like a real observatory. The "hex" part of the Sky Hex was born. With the same 3 or 4' sections I was going to make for the square box I could still get a shelter that was about 7' across and do it with fewer parts by not making a square box.

I laid out the floor plan -- six pieces of painter's masking tape -- on the floor of our warehouse at work and deemed the size to be just right. I don't know if it is true or not, but I felt that the hexagon shape, with one-piece walls, would also be a bit sturdier all by itself than a square with multi-piece walls. I thought a "belly band" around the middle of the structure would tend pull everything together, rather than try to collase the whole thing like it would if the walls were just straight. We shall see.

The last thing to guesstimate was how high the walls should be. The diameter of the shelter wasn't going to be very large, so they couldn't be too high or it would cut off a good portion of the sky. They still had to be tall enough to do some good at blocking light and wind. Being able to see out and not let the wind in are really not compatible...unless you stumble across the items in the picture above. PVC hinges!? Who knew?? They opened up a whole bunch of possibilities. With them the walls could be high enough to block stuff, but could be tilted out of the way when observing lower. Now I had a project!

I brought some of my telescope stuff in and set it up inside my masking tape dots, pulled out a measuring tape and went to town. With my Losmandy mount, 12" extension, and my Celestron 8 I figured about 68" would be a decent height. That would keep out most of the riff raff. However, for shorter/smaller mounts and scopes, or for looking down to the horizon, or for looking to see if that noise in the night was a bear, the minimum height looked like it could be somewhere around 48". Any lower didn't gain you anything. With the hinges none of that was a problem.

   

I did some quick estimating about how much stuff I was going to need and started in.

I started by ordering a few of the hinges to see if they were going to be sturdy enough to hold up half a wall. They were really nice. You depressed the button on the hinge to unlock it, moved it to the angle you wanted and then let go of the button to lock it in place. They were adjustable in 22.5° increments. Perfect. I ordered the rest of them. $18 a pair!

Home Depot online ordering has gotten a bit strange. It seems you can't place an order for more of something than they have in stock at "your" store, and then wait for more to come in before going to pick everything up. I don't remember it always being that way. "My" store didn't have enough of the parts at the beginning of the week. I kept checking. Just as I was about to head north to visit all of the stores in Albuquerque to find enough parts my store in the town of Los Lunas, had everything I needed in stock. Order placed. Order filled. Road trip accomplished.

   

With all of the parts in hand I was able to sit down with a micrometer to measure the dimensions of everything and make some detailed plans. PVC fittings from every manufacturer seem to be different sizes. For that reason each of the four different types of fittings for this project were all from the same manufacturer. The diameter of pipe from different manufacturers is also not created equal, so I bought all of the pipe I was going to need and it was all from the same company. I came up with some simple drawings and somewhat complex spreadsheets to make sure all of the pipe pieces were cut to the right lengths.

I knew this saw had a purpose. There were about 40 pieces of pipe in this first panel.

Once everything was cut it was time to sniff some glue. That stuff really does smell good, but the ventilation was on high, so I only got to smell it once-in-a-while and only lost a few brain cells.

Having no real good idea how to approch this I started building from the bottom up. It turned out to be a good idea. Everything was pretty straightforward. Only the top two rows were a bit difficult to put on. Since I was working by myself I could only glue one joint at a time, so as the pieces of pipe got shorter the amount of flex got less from the glued joint to the next unglued one. It was kind of like zipping up a zipper by working from one side of the frame to the other. It all worked out.

Poof! A wall panel is born. Four feet wide and about 68-1/2" tall. Originally I thought the hinges would be closer to the center of the panel and that the frame would need that second row down from the top to make the top half of the frame more rigid. After I measured things out when I brought the telescope equipment to the warehouse I determined that the hinges could be higher than half way (around 45"), but I kinda forgot about doing away with that second row from the top. Once I got this panel together it became obvious that the extra row wasn't needed. The frame was pretty sturdy. Prior to getting it all together I had no idea what it was going to be like. I may remove that extra row someday. I did remove it from the plans for the other four wall panels.

   

I hadn't decided what to try to use for the wall fabric, but I bought three "beach blankets for two" from Brazil to try out. At 56"x72" they were just the right size. The ad said that they were "luxurious". I don't think that word means what they think it does. They were nice, but not quite as thick as I had hoped. This one wasn't quite Roy G Biv, but pretty close. We'll see how they work.

   

A co-worker had used these Snap Clamps on one of his projects. They seemed to hold the top end of the blanket to the frame just fine. I ordered some. They were a little under-sized in that the blanket could be unsnapped not easily, but kinda. Which wasn't a bad thing. Since this was all made of plastic I thought I'd rather have a gust of wind blow the thing apart and have the sails be let go, instead of have the clamps hang on tight and have the whole thing blow away or snap in half. It's a theory in progress.

Now do you get it? They had to fit ON the bed of the pickup and my BackFlip2 bed cover. This was just right, but now I had to dream up a mount to keep them in place while on the road.

One down, seemingly hundreds to go.

The next thing I wanted to tackle were the clamping blocks I had thought up to hold the panels together. Unfortunately they turned out to be like William "The Refrigerator" Perry blocks to tackle. It seemed like a simple idea. Two pieces of wood with two 1" diameter holes for a piece of pipe from each panel to go through, and a bolt to make the two blocks clamp together around the pipes. I managed to get my butt kicked trying to make one...and a second one.

       

I didn't know redwood 2x4's had gotten hard to find. I used to use them all the time for projects. They had to be special ordered around these parts, but I managed to scrape up two pieces at our local lumber yard. They had three total, and they were using them to sit on out where the lumber was. I had the wrong kind of drill bits. Twice. The spade bit was just too violent to work on a small piece of wood that couldn't easily be clamped down, and the self-feeding bits were too grabby and hard to work with on the same hard to clamp down piece of wood. On top of that I didn't have the right size bit to fit around the pipes. The 3/4" pipe was 1-1/16" diameter on the outside. If that wasn't enough the range of travel on the drill press I had was 1/4" too short to go through a 2x4 the long way (3-1/2"). Trying to go as far as possible, and then turn the block over and come from the other side didn't go well. So I had to shave smaller blocks out of the 2x4's with the miter saw. It was a bit of a mess, but the Internets saved the day. I ordered some stuff and gave up on using wood.

I went back to cutting plastic and sniffing glue. The second piece I needed to build was the doorway section. I had no idea if it would be sturdy enough. It was mostly air.

Each section of pipe had a letter designation on my door drawing above, and on the drawing for the regular panels before. The letters were also in the spreadsheets, so I could tell what length to cut each piece. As I cut them I wrote that letter and the fractional part of the length on each piece so I could triple-check where each piece went before the glue was applied.

   

It took about an hour to get all of the pieces cut.

I followed the same bottom to top assembly plan as with the regular wall panel.

Somehow I even managed to get these two upper corners to go together without forgetting a piece. The gap is supposed to be there, because the spreadsheet said so, and because all of the different types of fittings had different lengths from the center of each fitting type to the ends of the holes, so gaps were needed here and there to compensate.

The keystone pieces...

Presto! It even fit on the masking tape dots on the floor. Sure as heck I'll end up stepping on the piece of pipe across the bottom and cracking it someday, but it had to be there or the sturctural integrity wouldn't have been. As it was it didn't flop around too much. I was happy. I figured I could make some kind of a wooden landing to cover up the bottom pipe and to force people to step over it. I knew where I could get some leftover redwood 2x4's.

I like people that bring me stuff...like the mailman. After the redwood fiasco I ordered 44 blocks of high density polyethylene (HDPE). This is the same kind of stuff that plastic cutting boards are made out of. I used it in a shelf project for my GM-8 mount. I also ordered two 1-1/16" Forstner bits, which was the correct outside diameter of the PVC pipe.

With that many blocks of plastic to drill I needed a jig. I had one, of sorts, that I had made for a woodworking project experiment that had just been sitting around. It would allow me to get each block in the same position under the drill bit. Since I had to drill through the block I drilled out the area under where the blocks would be.

I did a little bit of experimenting and found that a 23/64" bit drilled just the right hole for the 5/16"-18 T-nuts that I planned to use.

I got the jig clamped into position by marking the center point of the side of a block and then moving the jig around a bit before clamping it into position. That Jorgensen clamp came in handy. It had a long reach and the jaws were wide. Once everything was where it needed to be it only took about 20 minutes to drill the bolt holes in the 36 blocks. I ended up drilling 42 not just for the fun of it.

After I got the first two holes drilled I tried the system out, but the T-nut that takes brads to hold it in place just wasn't going to do the trick. The plastic was too slippery and the T-nut without any brads spun around. I thought about using JB-Weld to hold it, but figured that wouldn't stay stuck to the plastic for very long. I switched to the T-nut with teeth. I thought when I was buying them that the teeth wouldn't work well with the hard plastic, or that I might have to drill little holes for the teeth to go into, but the two that I set in place (with a large vice) seemed to be OK. They will only have a chance to fall out for the few seconds that the eyebolt is out of the block while the two halves are put around the pipes and the eyebolt is screwed back in, but they didn't seem too interested in falling out.

Zoom! Zoom!

Time to make the big holes. I wanted about 3/4" between the holes to make sure the fittings on each section didn't bump into each other, plus a little. Just to make it easy I marked the center of the holes 1/2" to either side of the 3/4" gap, so I ended up with 11/16". Good enough.

   

Oooo. Just as designed. The 1-1/16" Forstner bit turned out to be just the right size. When the two halves were clamped together they had just the right amount of grab on the pipes. I figured having the clamps be just a little loose would be better if the thing blew over. The pipes would be able to rotate and the whole thing would just go flat, instead of grabbing so hard that the pipes would be twisted and snap.

I've spared you the bone-chilling, spine-tingling details of what it took to get the two holes drilled in this first clamp, because I figured out how to do it correctly as I was wiping away the sweat and putting everything away for the evening. This clamp ended up OK, but it didn't go very well.

Operational check -- sat. I just laid the two pieces against the back of my pickup, attached the clamp, and then was able to spread the two sections apart to the desired angle. Easy peasy. One or two more clamps will go below this one at each junction between the sections when it gets set up for real.

Guy wires get attached to the eyes of the eye bolts, so "something" will go on the pipe below the position of this clamp to keep it from sliding down and loosening the guy wires since the clamps are not designed to squeeze the pipes tightly. The last thing you want as the whole thing is shaking in the wind is for the wires to loosen.

Still can't figure this out. It looks like the panels will also fit this way. This allows the end section of the bed cover to be opened if needed. I'm leaning toward simple foam rubber pads of some kind and simple ropes to keep things in place. I just have to come up with a way to keep the foam rubber in place, and find something to tie the ropes to. Still thinking.

Back to cutting for number three.

This is way simpler than the doorway. That doorway was a killer. It's also simpler than the first panel, because the extra rung above the hinges is gone.

Made it this far without a problem. I put each hinge on and just kinda eyeballed them into position. They have a bump in the plastic that I can line up with a line in the plastic of the tees or crosses, but the parts aren't always rotated the right way, so sometimes there is only the line in the hinge plastic and I just had to guess.

Done. One pipe didn't go all of the way in. Second from the left. I tried putting the top on the panel 'differently' than before. I never did it that way again. I'll try to fix this panel someday.

With three of the planned six sections under my belt I had only had one incident where the glue dried so fast that I had to throw away the part I was working on. I got brave and cut all of the pieces for the remaining sections, so just sniffing glue would be left. That was a lot of pieces. That was going to be a lot of sniffing glue.

When I was finished I went through all of the fittings and counted out everything that would be needed for the last three sections.

But wait! There's MORE! There really was. There were enough parts left over to to make one more section, with the exception of three rubber feet. I mean what self-respecting member of the Hill Tribes wouldn't want a SEVEN-sided shelter for their telescope? A Sky Sept! When in Santa's workshop north of The Wall you just keep cutting. Didn't take very long compared to making three sets of everything.

And a box full of parts for one. I picked up three more rubber feet after I finished for the day.

   

Two 10' sticks of pipe and a small box of small pieces remained. Not bad. I did have a collection of crosses left over from removing the extra rung and a few tees. Cutting really short pieces from really short pieces was a little too exciting with that miter saw, so some of these didn't get used. I cut on the wrong side of the line on that "S 11/16" piece, so it wasn't 14-11/16" by the time I finished. Only did that a couple times, but that was OK. They got used for some of the 2" pieces.

Snow in August. That was a lot of cutting in one day, but it only took a few hours.

Plodding along. Got panel four built and made all of the row portions for number five in one evening. Having the parts pre-cut helped a lot. Gluing together a whole panel from the beginning took about 1-1/2 hours with a couple of oxygen breaks. Good thing the ventilation in the area where I was working was good, or it would have taken longer...maybe it did and I just didn't notice.

I didn't get to work until later one night, so decided to just work on the clamping blocks. They're HARD! The Forstner bits didn't really do a great job of getting rid of the cut plastic, so I had to keep stopping and cleaning out the bit. They don't clog up like that when the material is wood.

Managed to get over half of them made in about an hour. A couple of them were messed up a little, but it didn't show in this picture...whew. Unfortunately some of the sets were unique in that the halves would have trouble being swapped with halves in other sets. Not a problem. They will be kept together all of the time with the eyebolts, except when they are being put on and taken off of the panels. I knew getting all of the parts to match probably wasn't going to happen. I'd hired me to cut and drill stuff before.

Almost the final push. With all of the pieces cut it was easy to get the panels partially built by connecting all of the horizontal pieces. Those are the parts for panel number 6 down at the far end.

Here is number 5 which was partially put together last time.

Number 7. We'll see if panel 7 gets built, or kept for spare parts.

The difference in how the pieces went together was shocking. Some parts fit together very easily and then the next ones, which had been treated exactly the same would have to practically be stood on (and I'm not light) to get them to go together. And a lot of the time it wasn't even obvious that the pieces were not in the right place. This was one of the pieces that fell about 1/4" short of all the way in before it couldn't be moved anymore (about 2 seconds or less). It was obvious that it was bad. I had to bring out the big guns and take off the extra bit. It will be a weak point, but I don't think it will matter.

2/3rds of what it was supposed to look like. At this point I still didn't have a real good plan of how to carry all of the panels around, but I was quickly getting them together to see how it was going to look, so I had to hurry up and come up with one. I still wasn't 100% on board with using the big beach towels for the covering. I still only had the original three.

Numbers 4 and 5 done. 6 and 7 on the shelf. 1, 2 and 3 in the self-storage place.

For the sixth panel I got a little smarter. Most of the holes that the pipe had to be glued into were 1" deep. What better way to point out that you failed to get the pipes all of the way into the holes than put a mark at each end of all of the pipes 1" from the end. It worked well.

The last joint. Unless I make the seventh panel. It's not glued yet. That's why you can still see the 1" mark. I managed to not mess up this sixth panel.

Ta da! Big enough to hold a human.

Seven foot diameter. Right on the money. I liked that carpet. It was made of polypropylene and seemed well made. I bought it from a seller on Ebay. It was just right. The next size up was 8-1/2'. That might not be a bad idea. Having the carpet go up the inside of the walls a bit might help keep the wind from blowing under my skirt. After I try the shelter out in the real world I'll see if the wall fabric will be enough or if a larger carpet would be better.

And there it is. Just what it was made for...except for being without the fabric covering and actually being outdoors.

This was well on the way to achieving the primary design objectives. It looked just like the pictures in my head. At this point I was kinda giddy. Maybe that was just the glue.

Ah ha! So that's what those hinges were for! When you absolutely, positively just HAD to look at something close to the horizon the upper sections could be tilted out of the way. One or all of them could be tilted down depending on where the night's observing was going to be done. I guess you could also make the tilting sections trapazoids, stick four hinges on the door section, and get the thing to make a bit of a dome on top when the sections were tilted inward. Maybe for version 2.

This was one of my lower tripod/telescope combos, so if a taller setup were being used the panels would not have to be lowered as much, which would, of course, improve the cold wind blocking ability.

I couldn't fight four hinges at once so three clamps were used to help me out by squeezing the hinge buttons, while I operated the forth one and adjusted the angle with my other hand.

Easy set up. Easy take down. Just attach or remove the blocks.

Quite a bundle of joy. This was the six panels, with possibly one more being added down the road. I had to get to this point to be able to come up with the right sized device for keeping them on the back of my pickup.

Good to know...

Other than the panels having quite a range of different heights it all didn't turn out too badly. Of course I hadn't gotten to the fun and excitment of trying to keep multiple pieces of fabric attached to the panels. These projects never seem to end.

If you build it, it must be hauled. I tried to come up with the simplest[-minded] way to keep the panels attached to my pickup. Above was the idea. With the panels tied off at each corner the only problem was to keep each panel from going its separate way and all of them turning into a pile of loose sticks.

They couldn't move too far forward, because the cab was in the way, and the ropes in the front kept them from moving backwards, so it was really just side-to-side movement that I was worried about.

I cut the lumber -- who knew you could freehand stuff on a table saw and cut a weird angle part? -- then screwed the redwood wedges on to the cedar pickets and glued a thin layer of rubber to the bottoms of the pickets.

How to load the carpet was still a work in progress, but that's the whole concept.

Getting the blocks finished had to be done. That little vice sure worked well. The going got a little easier when I figured out that a lot of the bit jamming problem had to do with pushing down too hard and trying to rush the drilling. Lightening up helped.

Done! I made enough for seven panels or six and some spares.

Number 7. I figured I might as well put it together. I put the magic 1" mark on everything and started in.

This slip-up again. These short pieces were tricky. Something about them seemed to make the glue dry extra fast and there just wasn't much pipe to grab to fight them into position.

The real final joint...unless I decide to make it an octogon someday.

       

Some of the blocks grab the pipes tightly, and some, like the top one on the left which is now down in the middle, don't. With the bottom two mounting points it doesn't matter. They can just slide down until they come to rest on the tops of the fittings. The top one can't be allowed to slide down. It will be where the guy wires get tied to. If the blocks slip the guy wires will become loose. To keep them in place I glued a half-length snap clamp to each outer pipe. This was in the original design, but I had planned to use a normal PVC coupler fitting. Using the snap clamps was way easier and quicker.

   

I suppose it will depend on the circumstances, but the structure seemed sturdy enough with just two blocks at each junction. It was designed for three as in the right picture above. You can see the glued-in snap clamps in action under the top clamping block.

The Septagon!

Gonna need a bigger carpet for the sept. There is an 8-1/2' foot version rug which would be just right.

VERY good! 80 pounds.

With seven panels it goes to 92 pounds. The original idea was to keep the weight around 100 pounds. Mission accomplished.

The block stoppers. The one that is a little chewed up was the first one that I glued on. I had a brain fart and put it too high. I was able to cut it with my Dremel tool and peel part of it off before the glue was set up. A little sanding made it look better than this.

With all of the panels finished it was time to finish up the rigging for transport. I stacked all seven panels -- worst case -- onto the racks I made and started sniffing burnt rope. I have a hot knife machine for cutting rope and burning the ends so they don't frey. I love that thing.

The plan was pretty straightforward. Tie down all four corners and let the two racks do the rest.

Once the four corner lines were in place I ran one line from the front left corner, down to the middle of the two lines at the rear corners, which were tied together, and then back up to the front right corner line. A trucker's hitch there cinched all four corners tight. If any of the four corner ropes became loose I only needed to tighten that one hitch.

The pickup's frame has these square holes in various places. I used open S-hooks to connect the front two ropes which then went up between the cab and the bed of the pickup and to the front two corners of the panels. The tension on the lines kept the hooks in place. The black part is the bottom of the plastic bed. Where the rope is heading is the gap between the bed and the cab. There were no sharp edges for the rope to get cut on going this route.

   

For the rear two corners I was able to connect to the tie down rings in the bed and then come up through the hole where the bed, BackFlip2 cover and tailgate meet. There are a couple of chaffing points there, so I bought some small plastic tubing for the line to go through. The rope that I used was a cheap $4 per bundle of 50' from Walmart variety. It was rated for 100 pounds, but the thing about it that caught my eye when I was first messing with it was that it hardly stretched AT ALL. It became my instant favorite rope for the job.

   

I bundled up the carpet and tied it to the top of the panels with a single piece of parachute cord. An adjustable loop on the end around the carpet and a pipe, a half hitch in the middle around the carpet and a pipe, and then the carpet tied to a pipe at the front. Simple.

I threw a bungee-like cord around each side of the bundle as a little more insurance. It all worked out really well. Once all of the lines and their lengths were worked out I made another spare for each line. You can see that the four vertical wedges on the two racks were a little bit taller than they needed to be. That was in case I ever decided to make one more panel and turn the shelter into a dance hall. For just me I figured six panels would make it big enough.

To help keep the package of panels a little more level I added four foam bumpers to the panel that was designated as the bottom panel. That was the first panel I built. The rest of the panels could go on in any order with the door panel being the last one on top.

Up to this point I had never had more than one beach towel attached to the panels, so it was time to see if the towels were going to work at all. They did.

I only had three at this point, but that was enough to let me see what was going to happen at the corners. All of the bright colors and white were not really the usual dark and dreary colors of astronomy, but I wasn't sure how much difference that would make. The white interior walls could make it a bit easier to see what you are doing when inside the shelter. At least it looked interesting. After this bit of testing I ordered two more towels and then a few yards of several different blackout curtain materials.

       

With the towels being a bit wider than the panels a couple different things could be done at the corners. Clips, in this case just clothespins, could be applied on the outside, or the excess material could be gathered together on the inside and clipped together in there. Gathering the material on the inside made the fabric tighter. The final answer won't be clothespins, but maybe snaps or Velcro or bungee cords. After this I ordered some fancy stainless steel clothespins just to try out.

This was the concept of a belly band going all of the way around at the hinge level. I added two more ropes below this one to help keep the fabric in place. Other than getting the fabric to cover the remaining panels this was as far as I was going to go with this experimental arrangement. It was good enough to see what was going to be needed.

All of these clips and clothespins and belly bands were not going to be able to keep the fabric in place while the wind was blowing, but that was sort of the point. All of these clips and clothespins and belly bands were going to make it quick and easy to detach the fabric and keep the shelter from breaking and/or blowing away. At some point the pieces of fabric will be more sophisticated. I'm thinking of something along the lines of a mitten that slides on over the top of each panel.

The plastic snap clamps I was going to use to hold the beach towels on ended up working a little too well. They were pretty hard to slip on and off and I was afraid the towels would get ripped. I took a bunch of the clamps and cut some in half and a few others into thirds. Doing that also gave me many more clamps.

It was time to finsh the clamp blocks and it required a new toy. I'd wanted to get one of these for a while. This seemed like the perfect time. This Bosch router table wasn't too bad. The table could be a lot smoother for working on small items, but it did the job. It didn't dawn on me until I pulled it out of the box that it was going to take all evening to put it together.

I bought a new DeWalt DW618 router to go with it. I didn't want to be chewing up a lot of time mounting and unmounting my little Makita compact router. This one is also 2-1/4 H.P. vs about 1-1/4 H.P. for the Makita. The combo worked very well.

The collection of mounting holes for all of the different brands of routers were the main problem with this table. I only needed three of them for the DeWalt router. The rest were just potholes for the plastic blocks to fall into and get hung up on. Someone suggested filling them with bondo. That could happen.

The production line.

That plastic was hard, and the corners were sharp. A 1/8" roundover bit in the table and a few seconds knocked all the corners off. Slick! I just cleaned out the inside diameter of the holes with my pocket knife.

All dusted off and put away. This was a great buy.

Once the routing was done it was time to press in the T-nuts and give each block a 2-1/8" long 5/16" stainless steel eyebolt and washer.

To take the whole thing out into the world and give it a try these were the last piece of the puzzle. The green line shows which way the halves have to be turned to get them to match up. That will maybe just be something like a shallow hole drilled as a marker in the future.

Ready for Okie-Tex 2017 and the first field test...which I ended up not getting to go to. Oh well, there will be the Enchanted Skies Star Party 2017 in New Mexico in October. I'm helping with that one, so I have to go. I didn't make it to Okie-Tex, but it turned out to be a real mud bog event at the end. It still sounded like fun. It would have been a good test. I gotta get a bigger truck. Maybe then I'll be able to make this out of metal pipe if the PVC doesn't work.

This all took about five to six weeks to put together. I started the begining of August. It could have been done in two or so if I lived in a bigger town and didn't have to wait for stuff to come in the mail and didn't have to have a day job. I'll put a layer of paint on the pipes to finish it off.

THE END

2018-03-03