Building a Bridge

This was a quick little project this week. Wendy wanted me to build her a bridge. Not a bridge in the typical sense, but a bridge for the horses to walk across when doing the obstacle course. This would be our own bridge for practice and rehearsal, but it might also be used at some of the horse shows we go to, so it needs to be somewhat portable.

Framing the bridge

After some discussion, we decided that the bridge would be 32 inches in width by 4 feet in length.

I had some leftover 2×6 which I could use for the frame so the height of the bridge would be about 7 inches – the 2×6 plus the thickness of the boards on top.

I cut the 2×6’s to length and made the frame as shown in the photo. Given that the horses would be walking over this, I wanted it to be good and sturdy, so I used three (3) rails to support the top boards with cross braces in between.

I had to purchase some 5/4 pressure treated deck boards for the top. I cut each of them to 32 inches in length on my table saw.

The frame was assembled and squared up with the help of four corner clamps and two longer clamps. I used 3 inch screws to hold it all together. Two of the pieces of 5/4 inch decking were used for the ends.

After assembling the frame in the shop, we carried it upstairs to the garage before adding the top boards, which would add considerable weight.

Finished

The top boards were attached using 1 1/2 inch wood screws. I also drilled a couple of holes in each side rail with a 3/8 inch bit and inserted a 24 inch piece of nylon rope through the holes.

I tied knots in the ends of the ropes and sealed them with a torch. They should last a long time.

The finished bridge is heavy (it needs to be), but 2 people can lift it and carry it with the use of the rope handles on the sides. It should fit in my truck bed if we need to take it to a horse show.

I didn’t add anything else, but there is always the option to add handrails to the sides of the bridge. These would be mostly decorative so I would probably make them so they are easily detachable. PVC pipe would be a good material for this.

All in all, this was a straight-forward project that took only a couple of hours of actual work. It should keep the horses occupied for years to come.

Another Cutting Board

Had a request for another cutting board from my real estate agent daughter. This is the second one for this client.

This was different type of cutting board than the first one, still made from solid maple laminate.

Because of the style of board, I was able to cut the letters a little bit bigger and thus a bit deeper with the 90 Degree and 60 Degree V-bits.

The logo symbol at left was a simple pocket cut with a 1.5 mm single flute downcut bit.

After giving the piece a light sanding, some clear epoxy was applied and allowed to cure for 72 hours. The epoxy fills the carved out areas and makes the surface nice and smooth.

Then it was given a good sanding to remove excess epoxy followed by a coat of my beeswax/mineral oil mixture. That finish really brings out the beauty of the maple – the photos don’t do it justice.

As before, this was designed in Carbide Create and carved on my Genmitsu 3018 PROVer CNC machine using CNCjs.

A sign for the Farmhouse

Wendy asked me long ago if I could make a sign for her family farmhouse. I bought some plastic sign material almost a year ago from Trotec at engraving-supplies.ca but never got around to making the sign. Well, I corrected that today.

The sign as it came off the CNC machine

I had made a small name sign on a piece of scrap 2-colour plastic I had laying around so I was pretty sure that my feeds and speeds were good. When milling plastic, the thing to avoid is going too slow. If you do, the plastic will melt on the bit.

So I used a 1/8 inch single flute upcut bit with a feed rate of 500 mm/min which is about double my normal feed speed for wood. I also took a deeper per pass than normal because of the softer plastic material. I cut the design to a depth of 0.6 mm in a single pass into the 1/8 inch (3.175 mm) material. These settings seemed to work well as I made lots of plastic chips and no melting.

The sign presented a challenge because at approx. 300 x 300 mm, it was twice as large as the work are on my 3018 PROVer (280 x 165 mm). The design had to be split into two separate carves, each of which being within the limits of my machine. After carving the top half of the sign, I repositioned it on the bed and cut the bottom half. The piece was held down with double-sided tape as it was too big for me to clamp it. Man, that tape really holds! I was worried I might break it prying it off the tape, but I was careful and successful.

The finished sign.

I have a happy customer with this one!

Polar Unite

I bought myself a new fitness smart-watch, the Polar Unite.

Polar Unite

I’ve been wearing a Polar A300 watch for almost 4 years now. Got it when I was in cardiac rehab after my heart surgery. In combination with a Polar H10 chest strap it did a great job of tracking my heart rate during workouts. However, it did require the chest strap to be worn to get the heart rate.

This new watch has built-in heart rate monitoring right on my wrist, so it’s there 24/7. It also has a touch screen with a vivid colour display. It connects to the Polar Flow app which I’ve been using to track my training sessions. I get a lot more information on this new watch including my training history in charts and graphs. I think I’m going to like it.

I’m a big fan of the Polar line of fitness products and I didn’t want to see the old one go to waste. So my old A300 smart watch found it’s way onto Wendy’s wrist. Got it all set up for her, the change-over was pretty straight forward, and she’s looking forward to tracking her own daily activity tracking.

TV Stand Project

This is another “retro-post” of a previous project. Last year Wendy wanted a new TV stand for Hanna’s Irish Vacation Farmhouse. We decided to make it from some nice wormy maple that I was able to source locally.

Finished TV Stand in place at the farmhouse

After careful measuring to fit both the available space and the farmhouse’s TV, I came up with a design and started cutting the pieces and began the assembly.

Table during assembly

All the joinery was done with pocket joints. It’s a good effective way and provides a strong joint.

Assembly

I decided to personalize this table by carving “Hanna Farm” into one of the front rails. Before assembly, I put the piece into my Genmitsu 3018 PROVer CNC machine and made the carving with a 90 Degree V-bit.

The top

The top was a beautiful piece of laminated wormy maple and was the single most costly item in the whole table. I mixed up some clear epoxy and filled in the knot holes on the top. It was then given a number of coats of polyurethane. The rest of the pieces got the same polyurethane finish before final assembly.

All in all, this was a very worthwhile project. The wife was happy and that’s the most important thing.

Homemade ADS-B antenna

I wasn’t really satisfied with the range of reception my ADS-B receiver was getting. With the kit antenna, I was receiving signals from aircraft up to about 50 nautical miles, but more reliably only really 30 miles. That was with the antenna situated inside my patio door. I found that moving it outside increased the range but it wasn’t a practical idea to have the patio door cracked open in March. I wanted a more permanent setup with even better reception.

After a bit of research on the interwebs, I decided to build myself a homemade “co-co” – coaxial collinear – antenna. I made my antenna based on a couple of YouTube videos and this excellent description at www.balarad.net

A collinear antenna consists of a number of equal length segments of coax cable joined by alternating the center conductor of one to outer sheath of the next. The ideal length of each conductor is calculated based on the frequency to be recieved (1090 MHz) and something called the coax velocity factor. Luckily there are calculators on-line like this one at jeroen.steeman.org

The videos and other resources I found had calculated the length for each antenna segment at either 116mm or 118 mm. So after careful consideration, I decided to split the different and go with 117mm. Fortunately, I had some unused RG6 coax cable which I was able cut into the required segments.

Assembling the collinear coax antenna

The antenna can have as many segments as you wish, but it seems that any more than 8 doesn’t offer a great deal of improvement. So I went with 8 segments. The photo above shows how the segments are joined with the center conductor of each inserted into the sheath of the next. A piece of electrical tape not shown here is placed between the conductors. Then each connection is wrapped with more electrical tape.

After assembling all 8 segments (the last one has an F-type fitting) the whole thing is inserted into a piece of 1/2″ ABS pipe about a meter in length. The top is capped and the fitting at the bottom is wrapped with electrical tape until it fits snug.

antenna mounted to deck

I mounted my new antenna outside on the corner of the wall of my deck and ran a 25 foot piece of RG6 coax cable into the house to the NooElec SMArtee SDR reciever on my Raspberry Pi 4B computer.

So was it worth it? Absolutely, my reception has gone from 30-50 nautical miles to 150-200 nautical miles. At times I have been receiving signals from over 100 aircraft. That’s a big jump form the 10-15 I was getting before.

My ADSB data is being fed to the flight tracking services of ADSB Exchange. If you check their website, you will see aircraft tracked by my ground station (and many others all over the world).

ADS-B antenna

Here’s a couple of screen captures that show the reception I had with the kit antenna (top) and with the new “co-co” antenna (bottom).

Reception with kit antenna
Reception with outdoor “co-co” antenna