The GPS and XM antenna mount. This is the only all aluminum mount I made so far. One of the antennas specified that it should be mounted on metal for best reception.
The black GRT GPS antenna on the left mounted with two tiny screws into threaded holes in the back. I know everyone has a trick for transferring the hole pattern to a mounting surface, but here is one more. I save scraps of that clear plastic that toys and other products come packed in. I trim a piece to match the mounting surface of the gadget. I mark the holes by holding against the mounting surface of the gadget and drawing the hole location with a Sharpie. It's great because there is no measuring. You can simply see the holes. I then drill the holes in the template, hold it on the mounting surface and mark it there - perfect every time.
I have GPS antennas for the Grand Rapids WAAS unit and the Avmap EKP backup unit. I also have an XM antenna for weather and music. They need to have a clear view of the sky. They see through fiberglass, but not aluminum or carbon fiber. I thought about mounting them on top of the landing light housing, but there is the carbon battery access door above that area. I ended up doing what most people do, mounting it on the canard, just forward of my pitch trim servo mount. I used .032 aluminum and my cheap Harbor Freight metal bender. It turned out to be sturdy and very strong.
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It seems like you need to make or modify a mount for every gadget in the plane. First up, a mount for the Grand Rapids magnetometers. I got dual AHRS and that means dual magnetometers. The manual says that they need to agree with each other within 1/2 degree in pitch and yaw. I figured that would be impossible (for me) to accomplish with separate mounts or even with fiberglass. I decided on a one piece dual mount. It is fairly simple and consists of 2 plates, 2 angles and one piece of bar stock. They are both riveted and bonded with structural adhesive for extreme rigidity. It came out pretty well.
Here is a front view, from the side that will face out of the strake. The nose of the aircraft would be to the right.
Here is a top view. Note the slot for adjusting heading. If Andy's product is the Millin Beefy Yet Highly Adjustable Mount, this can be the Riley Somewhat Adjustable Mount (some jiggery pokery required at time of installation)
Here are the magnetometers in place on the mount. It is light, sturdy and actually within a fraction of a degree in pitch between the two.
Here are the magnetometers on the mount viewed from the side of the mount that will be glued to the bulkhead in the strake end. I still need to rough up the surface a bit to ensure a good bond.
Here are the magnetometers on the mount propped into the location where I will affix the mount to the side of the baffle with structural adhesive. I will get the plane perfectly level, use plumb bobs fore and aft along with the I beam that came with the kit to get a line next to the plane which is perfectly parallel to the longitudinal axis. I will then measure in to the mount from that to get the mount aligned, then structural adhesive it in place with a collection of jigs to hold it in place until it cures. Once this is done, I am committed as to pitch unless I use brass or nylon shims. I can bend to adjust in roll and use the adjustable feature for the most important axis, yaw.
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Next up, the mount for the autopilot roll servo. On my first Velocity, I just glassed aluminum hard points to the floor. However, with the Dash 5 cut down keel, the bell crank faces up and is about 6 inches off the floor. The rod end bearing and push rod need to have a 90 degree approach angle to the bellcrank, which means that the servo arm attach point and the bell crank attach point need to be at about the same height off the floor. I decided to accomplish this by building a u shaped box base out of 1/4 inch plywood with 2 bid on each side and aluminum threaded hardpoints on the underside. I made up a cardboard model first and used that to build this. I can then fit and file to get it just so before glassing it to the floor in final position.
Here is an end view of the assembly. You can see the edge of the hardpoint and the holes drilled and tapped.
Here is a side view of the roll servo mounted on the completed assembly.
Here is a top view of the finished roll servo and push rod mounted on the mount. I am going to wait to glass it onto the floor of the fuselage until I remount the wings and get the required up and down travel. The servo has a maximum allowable travel of 2 1/2 inches so that I will need to drill a hole in the bell crank slightly closer to the center of rotation to mount the rod end on it .
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Next up is the supplemental oil cooler mount. It comes as a kit with a 3 inch flange, two side panels, a top, an oil cooler just like the one up front and some rivets and bolts. You will need to file the top part to get it to fit perfectly and to silicone a gap between the cooler and the mount at the top. (flange side)
Here is a side view of the completed mount. The part on the left will face up and will accept the 3 inch SCAT tube from the left plenum runner. It will then exhaust warm air directly into the bottom of the cowl and out the back.
Here is a view of the finished mount from the side that will mount to the firewall.-------------------------------------------------------------------------------------------------
Mount number three, the mount for the Grand Rapids Engine Information System. Since I have two 8 1/2 inch EFIS units in the panel which can display the same information, I will mount this on the cabin side of the firewall. The idea is to make a mounting surface for the four mounting holes in the unit and stand it off enough to clear the data ribbon cables coming out of the back. I'll then simply epoxy the back of the mount to the firewall.
I used a Dremel to make recesses for 1/4 inch thick hardpoints at the ends of the U so that I can drill and tap them to mount the EIS. I made shallower recesses all around the other edges so that I could add a thin layer of microballoon and cover with tape glass for a better finish and more strength. This is my setup to do all of the tape glass and the hardpoints in one night. Note the duct taped popsicle sticks clamped on to hold the tape glass in place on the sides. Without them, you will find that the micro slowly oozes down and in the morning you'll find it in a puddle at the bottom of the part. Note also the wax paper which serves to protect my wife's countertop (and me from her if I goop it up). It is 0nly in the 20's out in the garage, so this one will set up overnight on the kitchen island. Putting the hardpoints down on the counter surface ensures that they will be flat and even for the mounting surface of the EIS.
It is finished except for mounting the EIS and weighs only 3 1/2 ounces. Not bad!
And here it is, the completed EIS mount. It is drilled and tapped for 6-32 machine screws and I found some nice black screws. I'm trying to resist the urge to paint the mount. Andy's looked nice painted black, but I figure I will be gluing the thing onto the cabin side of the firewall, which is also au natural, so I think I'll just leave it.
Next up, I have the oil cooler, in line filter and Weldon fuel pump ready to mount. I didn't have enough real estate to mount them right to left as I wanted them unless I screwed the filter right into the pump. Scott Baker fabricated the fitting for me and it is being shipped out tomorrow. Hopefully, my firewall will have the filter, cooler and pump mounted by next weekend. Pictures to follow.
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