finally got back to working on my miata roll bar install

General chat that fellow COM'ers may be interested in.
Post Reply
n1gzd
Speed Racer
Speed Racer
Posts: 483
Joined: Sat May 28, 2011 8:48 pm
Location: Acton, MA

finally got back to working on my miata roll bar install

Post by n1gzd » Sun Jan 08, 2012 8:00 pm

Hi,

I did not really get moving on this last month because of the holidays and work schedule. However, I worked on it today finally.

I am installing Hard Dog Hard Core Hard top with double diagonal.

Here are my comments and issues so far:

I like the design and quality.

There were important things that I did not see in the instructions (I am pretty sure that I am using the correct document). As some of you warned me, they should have instructed that the seats be removed (based on language later in the document it is clear that they think that you can do this without removing the seats - ridiculous).

I carefully cut out the section of the hat shelf using the pattern that was indicated in one of the drawings (hard core hard top needs hat shelf cut for clearance of the rear braces). However, after I got it done and tried fitting it, I determined that it was not even close to being correct if you have the double diagonal. I had to cut a significantly larger area (and a different shape was needed than the one in the drawing that I used). On one side the "X" barely clears the fuel tank itself. I will need to do similar cutting of the metal cover that was removed earlier (but now I know what shape needs to be cut).

Because of the unexpected differences in the fit of the model with the X brace I had to attempt to install and uninstall the bar over and over and over (as I experimented and cut more metal and played around with the wires). I scratched up the car paint a lot and also chaffed the wiring insulation a lot. I think that it was all superficial.

I did this without a friend to help. It was difficult for me but I was able to do it (as I was able to remove the hard top as well. The trick is to stand up in the middle of the car with the soft top down (seats need to be out).

By the way, I chose to do this work without uninstalling the soft top. I used "spark paper" to protect the rear plastic window (during cutting the top had to be up so that it was out of the way) and to catch metal filings below where I was cutting. I like spark paper and it works well for me. However, because my work was interrupted by the holiday I left it stuck too long and it left a residue on the plastic. Can I use something like white gas to get this off? I know that it is ok to use that on a lexan aircraft windshield. Anyway, this is not important yet.

There are two large rubber plugs that need to be removed from the body or roll bar feet will not lie flat. There was no mention of this in the instructions (unless I missed it somewhere).
I covered up the holes with foil tape. Also, it was necessary to remove some seam sealer on the drivers side where the outside edge of the rear foot sits or it would not lie flat either.

The problem that I am running into today is in understanding how the bar should bolt up to the shelf area where it sits below the seat belt reel.
I am pretty sure that the seat belt reel mount point goes aft of the bar (bolt goes through the hole in the roll bar before it goes through the tab at the bottom of the seat belt reel. However, if I do that then there is a gap between the car body and the verticalish part of the roll bar foot (while the foot in the trunk is lying flat). Am I supposed to need to shim it. Before I tried to install the seat belt reel it seemed to fit correctly. What am I doing wrong?

Some pictures:
riveted parts that the instructions said to remove from the seatbelt reels.
riveted parts that the instructions said to remove from the seatbelt reels.
2012-01-08-056.JPG (129.02 KiB) Viewed 1774 times
passenger side hat shelf before cutting.
passenger side hat shelf before cutting.
2012-01-08-060_cropped.jpg (82.65 KiB) Viewed 1774 times
passenger side hat shelf after cutting.
passenger side hat shelf after cutting.
2012-01-08-091_cropped.jpg (80.88 KiB) Viewed 1774 times
see next entry for rest (only permitted three)

n1gzd
Speed Racer
Speed Racer
Posts: 483
Joined: Sat May 28, 2011 8:48 pm
Location: Acton, MA

Re: finally got back to working on my miata roll bar install

Post by n1gzd » Sun Jan 08, 2012 8:08 pm

Few more pics:
Drivers side hat shelf after cutting. Picture is dark but you can see that I had to cut the metal back right to the edge of the tank. The cross bar almost touches the tank.
Drivers side hat shelf after cutting. Picture is dark but you can see that I had to cut the metal back right to the edge of the tank. The cross bar almost touches the tank.
2012-01-08-093_cropped.jpg (78.65 KiB) Viewed 1771 times
my fingers show where there is a gap if I put the seatbelt reel mounting tab aft of the vertical part of the bar mount (trunk feet are flat).
my fingers show where there is a gap if I put the seatbelt reel mounting tab aft of the vertical part of the bar mount (trunk feet are flat).
2012-01-08-094.JPG (77.25 KiB) Viewed 1771 times
what the bar looks like without the seat belt bar installed yet.
what the bar looks like without the seat belt bar installed yet.
2012-01-08-088.JPG (123.15 KiB) Viewed 1771 times
I would really appreciate some help getting the bar to bolt up perfectly. I can't drill the holes and bolt it up until I solve this mystery. If there is an obvious thing that I am doing wrong that you can point out then perhaps I won't need any help.

thanks,
Rebecca

n1gzd
Speed Racer
Speed Racer
Posts: 483
Joined: Sat May 28, 2011 8:48 pm
Location: Acton, MA

Re: finally got back to working on my miata roll bar install

Post by n1gzd » Sun Jan 08, 2012 8:30 pm

More pics:
for my year car you have to grind off the outside upper stud for the computer bracket (and modify the bracket which I did not get to yet).
for my year car you have to grind off the outside upper stud for the computer bracket (and modify the bracket which I did not get to yet).
2012-01-08-052.JPG (58.62 KiB) Viewed 1763 times
hope to finish this up next weekend so I can put the pieces sitting on top of and behind the Desoto back on the car (in the way). I need the room to start the mess for the next project (rear bulkhead for Midget and updated suspension for Miata)
hope to finish this up next weekend so I can put the pieces sitting on top of and behind the Desoto back on the car (in the way). I need the room to start the mess for the next project (rear bulkhead for Midget and updated suspension for Miata)
2012-01-08-098.JPG (132.47 KiB) Viewed 1763 times

WillM
Administrator
Administrator
Posts: 1453
Joined: Mon Oct 06, 2003 10:14 pm

Re: finally got back to working on my miata roll bar install

Post by WillM » Mon Jan 09, 2012 10:15 am

Hi Rebecca,

It has been several years since I've touched a rollbar install, but if I remember correctly, the rollbar bolts are a bit finecky to install. Things need to be aligned just-so for the bar to go in square.

The two bolts you are having trouble with are the first two that you install to secure the bar in place. As such, they are a requisite PITA to align properly, and the fact that other hardware bits (the seat belt reels) are involved doesn't make it easier. I would position the bar as close to 'in place' as possible, then work on one side to get the first bolt threaded. Then focus attention on the 2nd bolt and get it aligned and threaded. Then I'd alternate back-and forth a few times to walk the bar into place. Pop your head in the truck and check that the rear mounting plates aren't getting hung up or digging into anything.

Once that is done, move onto the bolts that thread into the top of the seat belt towers.

Once those are done, start drilling. Drill one hole, thread a bolt. The rollbar mounting plates may not be flush against the sheet metal, but they will be. The important thing is that all 4 feet of the bar are resting solidly against the frame.

Are you using the correct instructions for your exact model rollbar and car?
The Bethania Garage's (Hard Dog Fabrication) shows this illustration for installation of M1 Hard Dog Hard Core Hard Top bars:

Image
96 Miata #72 SC
PRA 4 :sunny:

n1gzd
Speed Racer
Speed Racer
Posts: 483
Joined: Sat May 28, 2011 8:48 pm
Location: Acton, MA

Re: finally got back to working on my miata roll bar install

Post by n1gzd » Mon Jan 09, 2012 11:12 am

Yes. These are the instructions that I am using and I have that drawing. I am able to install that bolt exactly as the picture shows.
However, if I do it with the seat belt reel tab (as pictured) it sets the lower part of the bar mounting plate (the part that is almost vertical) out a little from the body (a large gap forms). Without the seatbelt reel installed I don't see this problem the bar assembly sits square against the body at all points.

Rebecca

n1gzd
Speed Racer
Speed Racer
Posts: 483
Joined: Sat May 28, 2011 8:48 pm
Location: Acton, MA

Re: finally got back to working on my miata roll bar install

Post by n1gzd » Mon Jan 09, 2012 11:46 am

I just talked to Tom at Bethania Garrage. He has cleared up this mystery for me.

The large gap that I am seeing under the lower mounting plate was intentional. He says that this lower mounting plate of the bar will bend when these bolts are tightened. They designed it this way on purpose. He says that I should tighten these bolts last.
He also apologized that the instructions do not mention that considerably more metal will need to be cut from the hat shelf if you are installing the X brace style bar (can't use the supplied drawing for what area to cut). They are going to add this soon.

Rebecca

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 1 guest