Doing the perfect roof...
Discussion
I have my new roof, I've read the article on The Griffith pages at least ten times and I'm now pooing myself! 
My old targa covering is off and I'm just about to remove the old glue in preparation to put the new (very nice and very black!) covering on.
What top tips are there to get it perfect? How have you done it to achieve an excellent finish?
I'm assuming I use the spray glue on the main body and the brush on stuff for the edges.
My main concern is the initial positioning. How have you gone about this if you've done it?
Do you do one side first and then mask it and spray the other side? The thought of spraying the whole thing and hitting the target first time is making me a bit nervous!!!
Any tips, hints and pointers greatly achieved.
My old targa covering is off and I'm just about to remove the old glue in preparation to put the new (very nice and very black!) covering on.
What top tips are there to get it perfect? How have you done it to achieve an excellent finish?
I'm assuming I use the spray glue on the main body and the brush on stuff for the edges.
My main concern is the initial positioning. How have you gone about this if you've done it?
Do you do one side first and then mask it and spray the other side? The thought of spraying the whole thing and hitting the target first time is making me a bit nervous!!!
Any tips, hints and pointers greatly achieved.
Hi
I intend to do this over the winter - I have already replaced the rear hood section and I have the matching hemmed and shaped mohair piece for the targa. I haven't been able to bring myself to rip off the prefectly good mohair yet - but the material weave is different so I just can't leave it.
I had thought of carefully positioning the material and using some double sided tape, front and back centre, to hold it in place. I was then going to roll back a one foot strip from one side, apply a narrow band of adhesive to the targa on that side and then carefully smooth the material in place, Leave to dry and then apply the rest of the adhesive and smooth the material into place working from the stuck side to avoid air bubbles. That way the glued strip will stop it from sliding out of place.
Was it hard to remove the old mohair and glue?
OscarT
I intend to do this over the winter - I have already replaced the rear hood section and I have the matching hemmed and shaped mohair piece for the targa. I haven't been able to bring myself to rip off the prefectly good mohair yet - but the material weave is different so I just can't leave it.
I had thought of carefully positioning the material and using some double sided tape, front and back centre, to hold it in place. I was then going to roll back a one foot strip from one side, apply a narrow band of adhesive to the targa on that side and then carefully smooth the material in place, Leave to dry and then apply the rest of the adhesive and smooth the material into place working from the stuck side to avoid air bubbles. That way the glued strip will stop it from sliding out of place.
Was it hard to remove the old mohair and glue?
OscarT
Hi guys,
I haven't gotten around to covering the folding section yet using BB's instructions, but I wrote one of the targa panel 'How Too's' on The Griffith Pages.
Cleaning off the old glue probably takes the most time. It's worth the elbow grease to get the targa panel completely free of the old glue and to give it a lite sanding to get off any remaining glue. Try and get it looking almost as if it was a new panel about to be covered for the first time.
Before you glue do a dry run. This will be easier with a second pair of hands.... Drape the material over the roof and position correctly making sure that there is enough over hang on the front and back edges. Stretch the stitched edges of the new material into their final positions. When you are happy that the material is properly positioned for all four edges clamp into position. I just used clothes pegs (see pictures in the write up). Then un-clamp one half of the roof and gently fold the material back making sure it doesn't shift or move out of position. Again this is where it is useful if a second person can hold the material so that it doesn't shift as you are applying the glue. Glue and lay... then repeat on the other side. Make sure the glue is brushed on evenly with no lumps. Once you have glued the top surface flip the roof over and glue down the edges.
I used a tin of glue and so painted it on... not having used the spray I don't know what it's like but I fear it could go everywhere if you're not careful.. Use which ever you are happier using...
I was pretty nervous about laying the material too, but if you are really concerned about not getting it riight on the first go it might be worth buying some Evo-stik Timebond Thixotropic contact adhesive from you're local DIY store. It's the same as ordinary contact except that while it grips well when first laid it doesn't make a permanent bond for about 10 mins. This means that if you are not happy with the way the material has gone down you can lift it and re-lay.
Hope this helps
G
I haven't gotten around to covering the folding section yet using BB's instructions, but I wrote one of the targa panel 'How Too's' on The Griffith Pages.
Cleaning off the old glue probably takes the most time. It's worth the elbow grease to get the targa panel completely free of the old glue and to give it a lite sanding to get off any remaining glue. Try and get it looking almost as if it was a new panel about to be covered for the first time.
Before you glue do a dry run. This will be easier with a second pair of hands.... Drape the material over the roof and position correctly making sure that there is enough over hang on the front and back edges. Stretch the stitched edges of the new material into their final positions. When you are happy that the material is properly positioned for all four edges clamp into position. I just used clothes pegs (see pictures in the write up). Then un-clamp one half of the roof and gently fold the material back making sure it doesn't shift or move out of position. Again this is where it is useful if a second person can hold the material so that it doesn't shift as you are applying the glue. Glue and lay... then repeat on the other side. Make sure the glue is brushed on evenly with no lumps. Once you have glued the top surface flip the roof over and glue down the edges.
I used a tin of glue and so painted it on... not having used the spray I don't know what it's like but I fear it could go everywhere if you're not careful.. Use which ever you are happier using...
I was pretty nervous about laying the material too, but if you are really concerned about not getting it riight on the first go it might be worth buying some Evo-stik Timebond Thixotropic contact adhesive from you're local DIY store. It's the same as ordinary contact except that while it grips well when first laid it doesn't make a permanent bond for about 10 mins. This means that if you are not happy with the way the material has gone down you can lift it and re-lay.
Hope this helps
G
Like Oscar I’ve done the folding section, quite pleased with the results and have yet to do the panel, which on mine is a good match, so I’m hanging on.
I would not use spray glue. Go to an auto-motive upholsterers and buy a tin of the right stuff, it’s not cheap but worth it. I found that whilst stretching it into position if it wasn’t quit position right I could lift and reposition if quick.
I used standard thinners to remove the old glue and yes that is time consuming but worth it again to get a good clean surface to bond too.
Cheers,
Simon.
I would not use spray glue. Go to an auto-motive upholsterers and buy a tin of the right stuff, it’s not cheap but worth it. I found that whilst stretching it into position if it wasn’t quit position right I could lift and reposition if quick.
I used standard thinners to remove the old glue and yes that is time consuming but worth it again to get a good clean surface to bond too.
Cheers,
Simon.
Simon.b said:
I would not use spray glue. Go to an auto-motive upholsterers and buy a tin of the right stuff, it’s not cheap but worth it.
Trust me Simon, the spray glue is the right stuff for this application and that very spray glue is used and tested to far higher standards than an aftermarket upholsterer would normally use. Brush on tinned glue can also work but is dangerous if you over apply, it's VERY easy to get lumps beneath the hard panel material. Brush on glue is certainly possible, in fact it's not too hard to use with a little care. But 3M Scotchweld 90 IS the correct type of adhesive for the main bulk (flat/curved expense) of the hard panel.
David H said:
Simon.b said:
I would not use spray glue. Go to an auto-motive upholsterers and buy a tin of the right stuff, it’s not cheap but worth it.
Trust me Simon, the spray glue is the right stuff for this application and that very spray glue is used and tested to far higher standards than an aftermarket upholsterer would normally use. Brush on tinned glue can also work but is dangerous if you over apply, it's VERY easy to get lumps beneath the hard panel material. Brush on glue is certainly possible, in fact it's not too hard to use with a little care. But 3M Scotchweld 90 IS the correct type of adhesive for the main bulk (flat/curved expense) of the hard panel.
In the end I called a local TVR dealer who in turn gave me the phone number of the upholsters that they used to refurbish the hoods. The upholsters told me that they used a trade version of Evo-stik Timebond Thixotropic contact adhesive and that the branded (Evo-stik) would be the ideal choice because the glue allows you a period of time before it bonds permanently so that you can lift and re-lay if needs be.
I don't know if you can find this product as a spray version, if you can you might find it easier. My only concern with sprays is that you can end up wasting a lot of glue through overspray which can be both messy and expensive, but again use which ever you're happiest using.
Evo-stik Timebond (in a tin) has the consistency of wax polish, like propper car wax or shoe polish, so its not runny like normal contact adhesive. Paint it on with a brush covering both the underside of the material and the panel and just make sure you brush it on evenly and with no lumps. I actually found that it spread nicely, didn't get any lumps and of course because it isn't runny there were no messy drips or spillage. I think the trick here is to make sure you coat the glue evenly, with no gaps and reasonably quickly. Don't go back over glue that has begun to dry as this is when you might create lumps.
G
Edited by GJR on Wednesday 7th November 13:39
I haven’t used the spray stuff, but like I said I went to the experts for mine. They told me what and how to use it, also made me up a spreader, which I didn’t actually use.
I cut a new piece of thick cardboard for each application varying the width depending on how much I was using. The glue spread very easily without any lumps or bumps and was easy to work into corners and around edges.
The largest flat area I did was the hoop and this was done in two stages. The rear hood is done fitted to the car and I just can’t see how spraying would give any advantage without the risk of over spray or extensive masking that would get in the way, though if you’ve managed it then OK.
Might be different on the panel as that is done off the car, but for me I’ll do mine with what I now know.
Cheers,
Simon
I cut a new piece of thick cardboard for each application varying the width depending on how much I was using. The glue spread very easily without any lumps or bumps and was easy to work into corners and around edges.
The largest flat area I did was the hoop and this was done in two stages. The rear hood is done fitted to the car and I just can’t see how spraying would give any advantage without the risk of over spray or extensive masking that would get in the way, though if you’ve managed it then OK.
Might be different on the panel as that is done off the car, but for me I’ll do mine with what I now know.
Cheers,
Simon
I used spray on adhesive for my carpets, and would suggest a few trial goes with the spray before using it in anger. Its not as easy as it would appear to get a nice layer laid down without a lot of mess around the edges - but once you get the hang of it its not so hard. I would always practice first rather than mess up the important bit of work 
Dave
Dave
spend said:
I used spray on adhesive for my carpets, and would suggest a few trial goes with the spray before using it in anger. Its not as easy as it would appear to get a nice layer laid down without a lot of mess around the edges - but once you get the hang of it its not so hard. I would always practice first rather than mess up the important bit of work
Dave
I agree with Dave practice first it can shock you how quick it comes out and the distance it can travel ( i am glad for covering everything up before hand.Dave
I have used both what David H supplied and the EVO one GJR and in my experience so far there isnt any difference in it doing the JOB it is needed to. I found the Evo stuff a little easier to use and didn't feel so rushed as it does give a little more time to move the material slightly if needed. I was unsure whether the Spray would give me that time but if you have perepped the roof thoroughly before hand this should be a problem anyhow.
Removing the old Glue for the targa panel took me about 3 hours and then and good sand down and cleaning you can get a real smooth surface bump free surface. If you find your roof has some holes or chips on it you can use the Fibre glass paste found in Halrauds and fill and sand down aswell.
I done the panel in two halves. matched the material to the roof and then clamped down one half as GJR suggested with pegs and G clamps( them plastic ratchet type ones are good for this). I the lifted it around half way and glued and replaced the material back down smoothing it down across the edges from center to outer edges..I thne clamped this end and done the other side the same.
Dont forget by lookig at your old one you will see some little tags you will need to cut into the new roof material to make it smoothly fit around the corners. It doesnt mater too much if they are messy where the go under to where the seal rail will sit as they are covered by the rail and the sealant you will add to finish of the edges.
HTH
I think Spend and BB have hit the nail on the head...
Whether or not the glue is in a tin or a spray form, it's more or less the same stuff.... it's contact adhesive (I am assuming here that the spray is traditional contact adhesive!?!?). When it's on and the material is laid they both do the same job very well. The only difference between normal contact adhesive and the Timebond stuff is that normal contact adhesive bonds the moment the two layers touch. If you do make a mistake and you try and separate the material from the panel you risk lifting the glue from their respective surfaces which would cause lumps and at worst you might have to start over again taking off the old glue etc. Timebond allows the glue layers to touch and grip like the normal stuff, but if you make a mistake the two glue layers are designed to separate easily... but only for a limited period of time.
It then just comes down to which method you are more comfortable with, and your confidence and experience in doing this kind of job.
Someone with a great deal of experience in this kind of job will be far more confident to use a spray quickly and cleanly, but as BB suggested, the tinned stuff allows you to take things a little slower (within reason) to make sure you're doing it right and getting everything coated that needs to be.
When all is said and done the professional companies use different techniques.... David H says that spray is best... I was told by an upholsters used by a TVR dealer that they used a trade version of Timebond and paint it on !?!?
Either way..... figure out which you are happier using and go with that.
G
Whether or not the glue is in a tin or a spray form, it's more or less the same stuff.... it's contact adhesive (I am assuming here that the spray is traditional contact adhesive!?!?). When it's on and the material is laid they both do the same job very well. The only difference between normal contact adhesive and the Timebond stuff is that normal contact adhesive bonds the moment the two layers touch. If you do make a mistake and you try and separate the material from the panel you risk lifting the glue from their respective surfaces which would cause lumps and at worst you might have to start over again taking off the old glue etc. Timebond allows the glue layers to touch and grip like the normal stuff, but if you make a mistake the two glue layers are designed to separate easily... but only for a limited period of time.
It then just comes down to which method you are more comfortable with, and your confidence and experience in doing this kind of job.
Someone with a great deal of experience in this kind of job will be far more confident to use a spray quickly and cleanly, but as BB suggested, the tinned stuff allows you to take things a little slower (within reason) to make sure you're doing it right and getting everything coated that needs to be.
When all is said and done the professional companies use different techniques.... David H says that spray is best... I was told by an upholsters used by a TVR dealer that they used a trade version of Timebond and paint it on !?!?
Either way..... figure out which you are happier using and go with that.
G
Edited by GJR on Friday 9th November 12:30
Right, the glue is finally off... Lesson one, don't piss about with solvents. I spent ages and it was really slow going and in the end I reverted to using some 3M paint stripping sandpaper. Much better 
It shifted the glue in no time and helped key the surface ready for the next bit.
I've had a bit of a brainwave
I'm going to invert the old covering and masking tape it to the new one to protect it from overspray and so I can also use my secret weapon without fear of damaging the new covering... A small wallpaper roller to help press it on. Cunning huh?
Wish me luck guys
It shifted the glue in no time and helped key the surface ready for the next bit.I've had a bit of a brainwave
I'm going to invert the old covering and masking tape it to the new one to protect it from overspray and so I can also use my secret weapon without fear of damaging the new covering... A small wallpaper roller to help press it on. Cunning huh?Wish me luck guys
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