Targa Panel Tang Replacement

 

Why Do It?

If your Targa Tangs have started to rust (like these) then you must replace them. There are two reasons for this, firstly they may not secure the roof well enough at high speed and secondly if left to rust the swell and will break the fibreglass in the roof panel leading to a more difficult repair (trust me I know). The Tangs are available from TVR Car Parts for approximately a fiver and the job is easily done in about 6 hours spread over a fortnight (allows for cure time and one panel done at a time).

NOTE DO ONE TANG AT A TIME - IT WILL SAVE TIME IN THE LONG RUN AND WILL GUARANTEE A BETTER FIT

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Get Access - Peel Back the material

The first thing you must do is get access all around the defective Tang. To do this carefully peel back the material for the hood cover and interior lining. Take great care in doing this as any damage may require the roof to be recovered or leave it looking tatty. I carefully peeled back an edge with a knife and then while applying pressure (as in the photo) I carefully used the knife to cut the glue very very slowly. I also had to create an extra cut to get the black outer cover over the old and new Tang, but did this on the underside of the tang so when the roof is fitted it doesn't show.

Once peeled back secure the lining out of the way (masking tape will work)

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Drill Out the Tang

Now carefully using relatively small drills (5mm was the largest I used) drill at the ends of the Tang (larger Drill) and all the way along the side (lots of individual holes) of the tang (smaller drills - 3mm was fine). While doing this make sure you drill straight, also ensure that you do not break the roof panel top or bottom surfaces and take your time. If you drill to a depth of 4-5cm that will be plenty (use your new tangs as a guide to set the depth of drilling)

Once drilled all round the tang take the largest drill you dare (3mm for me) and then drill at an angle across the holes you have already made to join them up. Take care that you don't break a drill as this can be difficult to remove. Once you have done this and are happy that the bond is now weak use some pliers to wiggle the tang back and forth until it comes loose. If it doesn't wiggle drill some more

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Tang Removed

You will be left with this
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Clean Up the Hole

You now need to use a file, dremel, drill or whatever tool you have to celan up the hole that is left. If you have drilled too far you will also have a hole into the hollow centre to the roof panel. If this is the case then use some fibreglass sheet and resin to fill this now as it will stop your resin running away when you rescure the new tang later
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Fixing the Tangs and Setting Position
No Photo Here

To fix the tangs they must fully align with the slots on the car, Therefore you need the car. Use a supermarket carrier bag to protect the car by placing it over the slots where the tangs engare the roof. Cover all slots where you are going to have new tangs being secured as some fibreglass will run out and will set on the car if you don't do this. Next loosely fit the roof panel you are not working on (if it is the uspper panel then you'll need to fit this after you have put the worked on panel on)

Now mix up some fibreglass resin and cut small strips of fibreglass sheet. Holding the Tang approximately central in the hole and at the correct height (pad up to the right height with fibreglass sheet) carefully push strips of fibreglass down all around the tang and add resin as you do so to ensure the sheet is full soaked. Build up this mix all around the tang quackly as you don't want the resin going off before the panel is fitted to the car. Continue this until you have almost completely filled the hole.

Now use masking tape to cover the wet fibregalss and hold it in the hole when the roof is fitted as best you can. If done well very little will ooze out. Then fit the panel to the car and leave until fully cured (at least a couple of hours).

Once cured remove the panel, clean up the mess from the carrier bags on the car and using a file clean up any excess from the roof panel. The new fibreglass finish will not be neat but this doesn't matter and it will also have migrated to the bottom of the panel. Clean up until no fibregalss protrudes beyond the edge of the roof panel and then secure the roof panel vertically so the tang area is upright and the top of the hole is level. Mix up some more resin and pour this into the hole until it is flush with the panel edge and allow to cure (protect the panel material from overspill). Once this has cured clean up with a file.

Re-fitting the Material

Next use some contact adhesive to coat the back of the material and the roof panel, then stretch the roof lining material over the tang and back into position ensuring that you smooth out any creaes and clamp until dry.

Now repeat the process on the next defective tang

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Pictures Courtesy of

Peter Dee

 

 

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