One of the few problems with my Subaru when it came from Japan was a broken roof antenna. This antenna got even more broken after an unfortunate incident with a low garage door. Ebay provided a replacement, but the replacement needed some modification to get it to fit on the car.
Full disclosure: this is definitely a KLUDGE. As I started this project, I had the best of intentions and a sketchy plan. It works, but… just!
There are a number of modern cars that have this style of roof-mounted antenna. For reasons I am unable to figure out, they’re what is called a “fuba” antenna. Volkswagens have been using these for years. Subaru North America didn’t use these in the 90s, but Subaru Japan did. I don’t know why the locale-based difference, but I do like these roof-mounted versions more than the North American pillar-mounted antennae.
I found out after my antenna arrived in the mail that Subaru antennae are different than the other manufacturers’ fuba antennae. The threaded mounting stud is slightly bigger than the 5mm stud used by VW and others, as you can see in the above picture. I let the antenna sit on the shelf for a few weeks while I thought about potential solutions to the problem.
What I decided to do was to cut off the stud from the Subaru antenna, drill it out, and thread it to make an adapter to allow the smaller replacement stud to screw into the larger Subaru antenna roof mount. As you will see, this was only marginally successful.
I started by peeling back the plastic from the original antenna, exposing the parts I would need to cut off and modify. There’s no turning back now!
Out came the threaded copper stud, and the excess was cut off with a Dremel:
If this was going to work, the drilling of this piece would have to be very precise. Marking the exact centre of the piece would be very important. For this, I chucked it into my drill press, and used a centre punch to trace out an exactly centred circle in the soft metal.
So far, so good. Here’s where things start to go wrong. All that precision went out the window when it came to actually drilling the stud. My drill press table and vise aren’t exactly calibrated, so it was about 0.5 to 1 degree off axis, which meant my hole didn’t perfectly line up with the stud.
This is the kind of job that should really have been done on a lathe. Unfortunately, I have yet to find a cheap lathe (though I’m always looking for one to come up in the classifieds). At the end of the hole you can see that it is way too close to the edge, resulting in some thin, fragile threads.
No matter - I press on! The next theoretical step would be to thread the inside of this hole with a tap to match the threads on the replacement antenna. I thought threading a steel nut onto the stud would help hold things together while I threaded. Nope! Snapped!
I decided that if this had any chance of working, I would need to support the outside of the threaded piece to keep it from exploding. The Subaru roof antenna actually has a small extension piece that could be removed from the car to hold the new adapter piece while I attempted to thread it.
There was a small amount of success had with this new method, as I managed to cut a few threads into it before it turned too far into the extension. Just enough to get some bite on the new antenna:
It’s not as far into the extension as I would have liked, but it’s snug enough to hold.
There we have it. New antenna with a kludgy execution. It’s on there, but to say I’m happy with how it turned out wouldn’t be accurate. One unexpected bonus is that the radio reception actually improved.
Cost breakdown:
$1.20 - Ebay shorty fuba antenna (shipped! How does anyone make money this way?)
Full disclosure: this is definitely a KLUDGE. As I started this project, I had the best of intentions and a sketchy plan. It works, but… just!
There are a number of modern cars that have this style of roof-mounted antenna. For reasons I am unable to figure out, they’re what is called a “fuba” antenna. Volkswagens have been using these for years. Subaru North America didn’t use these in the 90s, but Subaru Japan did. I don’t know why the locale-based difference, but I do like these roof-mounted versions more than the North American pillar-mounted antennae.
I found out after my antenna arrived in the mail that Subaru antennae are different than the other manufacturers’ fuba antennae. The threaded mounting stud is slightly bigger than the 5mm stud used by VW and others, as you can see in the above picture. I let the antenna sit on the shelf for a few weeks while I thought about potential solutions to the problem.
What I decided to do was to cut off the stud from the Subaru antenna, drill it out, and thread it to make an adapter to allow the smaller replacement stud to screw into the larger Subaru antenna roof mount. As you will see, this was only marginally successful.
I started by peeling back the plastic from the original antenna, exposing the parts I would need to cut off and modify. There’s no turning back now!
Out came the threaded copper stud, and the excess was cut off with a Dremel:
If this was going to work, the drilling of this piece would have to be very precise. Marking the exact centre of the piece would be very important. For this, I chucked it into my drill press, and used a centre punch to trace out an exactly centred circle in the soft metal.
So far, so good. Here’s where things start to go wrong. All that precision went out the window when it came to actually drilling the stud. My drill press table and vise aren’t exactly calibrated, so it was about 0.5 to 1 degree off axis, which meant my hole didn’t perfectly line up with the stud.
This is the kind of job that should really have been done on a lathe. Unfortunately, I have yet to find a cheap lathe (though I’m always looking for one to come up in the classifieds). At the end of the hole you can see that it is way too close to the edge, resulting in some thin, fragile threads.
No matter - I press on! The next theoretical step would be to thread the inside of this hole with a tap to match the threads on the replacement antenna. I thought threading a steel nut onto the stud would help hold things together while I threaded. Nope! Snapped!
I decided that if this had any chance of working, I would need to support the outside of the threaded piece to keep it from exploding. The Subaru roof antenna actually has a small extension piece that could be removed from the car to hold the new adapter piece while I attempted to thread it.
There was a small amount of success had with this new method, as I managed to cut a few threads into it before it turned too far into the extension. Just enough to get some bite on the new antenna:
It’s not as far into the extension as I would have liked, but it’s snug enough to hold.
There we have it. New antenna with a kludgy execution. It’s on there, but to say I’m happy with how it turned out wouldn’t be accurate. One unexpected bonus is that the radio reception actually improved.
Cost breakdown:
$1.20 - Ebay shorty fuba antenna (shipped! How does anyone make money this way?)
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