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Manager - AB7RG
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Not Your Typical Mobile Mount

Created by William Ohlrich, KD8QAE on 2020-12-08

"Editor's Note: Due to the popularity of some of eHam's older articles, many of which you may not have read, the eHam.net team has decided to rerun some of the best articles that we have received since eHam's inception. These articles will be reprinted to add to the quality of eHam's content and in a show of appreciation to the authors of these articles." This article was originally published on: 10/24/2012

 

 

Not Your Typical Mobile Mount

A custom fabricated fiberglass mount

A common problem facing mobile ham radio operators of today, is where to mount that modern radio, in your modern car, and not have your wife call you spaceman, or refer to your car as Medusa every time she gets in. We're all familiar with the suction cups, cup holder mounts, arms, braces, flex arms, vent mounts, bean bags, and the ever popular 3M double sided tape, sheet metal screws, and Velcro so many of us have resorted to using in the past. These mounts, while most serve their purpose, walk a thin line between being functionally ham sexy, and something a little better than that. The problem is they all look like add-ons. I'm very particular, I like things to gel, I don't like holes in my dashboard, I don't like wires strewn all over the place, I like the buttons within close range, and I don't mind building things to make that happen.

When I set out to mount my new Kenwood in my truck I had considered all the options mentioned above. Some were better than others, but none were very appealing. Did I mention I'm particular? My eyes kept coming back to this HUGE cubby hole I had in the middle of my console. It was at the right height where I could rest my arm and reach all the controls, plus it was enough out of the way I could tuck the radio head in there somehow and make it look decent, but how? As I continued to ponder, I broke my own rule, I brought out the roll of Velcro and stuck it somewhere.

Sure it was functional, and out of the way, but lacked that professional, custom look I wanted. I started my search on the net. custom "Ham Mounts." While bringing some results, most of them consisted of pig roasts with custom smoker grills, and a small number of antenna mounts. There were some pictures of mobile installs, some done better than others, but most if not all utilized the mounts we had spoken about earlier. Once again not quite what I had in mind. At some point I had been playing on YouTube and came across how to's for custom speaker cabinets made of fiberglass. This was more what I was looking to do. After some videos, and more brainstorming, I had settled on my plan of attack.

My first plan was to get some foam from the local craft store. Shape, glue and mold this foam into a shape I liked, then fiberglass over top of it to make it durable. Sounds easy in theory right? Well after some messing around molding the foam into shape, I began the resin and glass. Let's just say don't try this particular technique. The glass mat, and resin are hard to work with, and take all the detail and defined shape out of the foam as you slowly build a durable layer on top. No realistic amount of sanding will ever get the definition

back and make this a suitable final product. Fail. Back to the drawing board.

I thought back to another technique I had seen, this involved the use of a wooden frame, and fleece stretched over it. The fleece was then "painted" with fiberglass resin to create the hard shell of the part you're making. At the time, this seemed like so much extra work. Wood, fleece, resin. I should have started with this and just done it right from the beginning.

A quick trip to the hardware store and I was ready to begin. The first step is a wood frame. The frame only needs to shape the important parts, the baseplate, the area where the radio head will be framed, and the angle of the head. The area where the faceplate will be mounted is basically just a box with a back on it. It's then epoxied onto the base with a few pieces of scrap wood "tooth picks" to hold the angle I wanted the head at. A few tips at this stage:

1. Fabric is going to cover all of this. It doesn't have to be pretty. You're only making a frame for the important parts, size, general shape, angles, and how it will be mounted. Not pictured here is a few strips of wood on the bottom that will prevent the whole thing from sliding around once set in the cubby.

2. Think about wire routing at this point. Where will the wires be brought in? where will adapters for cat5 cables and such be hidden. After the above picture was taken I drilled a large hole in the middle of the rectangle frame, and also a hole in the base plate large enough to pass a cat5 cable and a barrel connector to connect the head control and mic cables through.

3. If the surface where you will be placing this is curved, there are techniques readily available on YouTube to custom mold a baseplate to match these curves. Basically it involves laying plastic over the surface you wish to mold(dash, cup holder etc.) then using something that can be shaped and held in place, cardboard or heavy weight paper works well, while it's held into place OVER THE PLASTIC applying a coat of resin. Keeping in mind resin is NASTY stuff, and this is being done inside your car, lay down way more plastic than you think you could ever need. Resin cannot be removed from seats and carpet. Once the resin is cured, the baseplate now molded in the contour of your dash can be removed and reinforced with glass mat, and more resin. You can then build your frame on top of that to you're liking.

 

At this point you're happy with all of the above. It's time to lay fabric. The material of choice for this seems to be fleece. It can be stretched and thus all the wrinkles removed, it also has some girth to it. This makes for a stronger shell later on. I cheated, and used what I had around, an old tee shirt. The shirt worked well enough and to this day has not cracked even after over a year of use in my mobile. Stretch the fabric as tight as you can, removing any wrinkles as you go. Any wrinkles will later need to be covered with Bondo, and sanded out if you wish to have a smooth finished piece. The fabric will be the final shape, so make it look as you want. Secure with staples around any points or lines you wish to have shown off in the final product. As you can see in the photo below I wanted a bit of a flat spot on both the front and rear of the base plate for a more custom molded look.

Once you apply resin, the wood and fabric will essentially become one piece. There's no need to secure the cloth to the opening where the radio will be mounted. It will be cut out later, and sanded smooth. Now the fun part, Resin. Run to your local hardware store and get a gallon of resin. I estimate a small project like this actually took less than a quart to fully coat and saturate the cloth, but the local Home Depot only sells gallons. Better luck locating smaller quantities can be found at local boating stores such as West Marine. A note of caution, FIBERGLASS RESIN IS NASTY STUFF. Work outdoors and in a well ventilated area. Wear gloves, and a respirator. They aren't very expensive at your local home store. I have seen people work with this stuff with only a fan running for fresh air, attempt that human trick at your own risk. Saturate the cloth while the resin is fresh and easy to work with. You'll have around 10 minutes working time after the hardener is added to the resin to "paint" the cloth and saturate it. After that time you'll notice the resin will start to become thick. The smoother this application is, the less filling with Bondo, and sanding later you will have to do.

Once your resin has hardened, you can give a quick sanding to smooth out any air bubbles that may have formed during the curing process. I've been told that a heat gun can be used while the resin is still wet to remove any air bubbles, I have not tried this trick myself. Hardener in the resin helps cures through a partially exothermic reaction, heat from a hot air gun will speed curing. If you're very lucky you may be able to sand in several grits to get the finish smooth enough for paint, or a filling primer. In most cases a thin coat of Bondo will be needed to fill any voids, such as the impressions formed by the staples. Take your time here, just like body work, the smoother the surface is the better the final product will look. Self leveling primers may hide some scratches, paint won't wide anything. Use varying grits of sand paper and a backing pad, or block when applicable.

From here it's on to finishing, primer and paint. Use what works, and more importantly what matches your interior, I nothing much more to add to that. I used Velcro on the rear of the radio head, and a piece within the rectangle to secure the radio to the new mount. My wires for the control and the mic enter from the bottom and hook into a couple of barrel type connectors for CAT5 lines epoxied on the underside. From there I can plug my mic easily into the bottom, as well as the stock cable from Kenwood used to plug the head directly into the radio body. On Kenwoods V71 it's a proprietary cable of CAT5 on one side, and a weird almost RJ11 on the other, this solution works for me, and was cheaper than purchasing the separation kit just for the cable. As a final step I applied some thin strips of the soft side Velcro to the bottom on the mount around the perimeter to prevent any kind of scratching or marring to the surface of my dash. Install, plugin and enjoy.

Questions and comments appreciated. 73 N8DOA

 

 

 

AB8JC2021-04-06
Not Your Typical Mobile Mount
Now, you can just 3d print custom stuff, or find a friend with a printer.
WO7T2020-12-13
Not Your Typical Mobile Mount
Keeping with the no-drill approach, go to Amazon.com and check out "WixGear Universal Flat Stick On (2 Pack) Dashboard Magnetic Car Mount Holder" to mount microphones in autos. Depending on material of button on back of mic, may have to epoxy on a steel washer matching the button size. Even in shack they are nice for keeping hand mics in place, and not strewn about.
W9WLW2020-12-10
Not Your Typical Mobile Mount
Terrific article, and what a creative way to mount a mobile radio head. I have tried some creative mounts myself through the years, but yours looks very professional.