JPS # 044 body restoration.

[CHANGES]

SET UP and PLANNING.. 

Here we are at the start of the body restoration on JPS # 044 .. 

There is evidence it has had previous repair work, with a half rear quarter section put in ..  Unfortunately this has not been done that well and is very easy to see..   As we have said in previous threads , any impact repair on GRP has to be explored with consideration of how far the gel crack will travel .. The usual stress points along with the direct connected area will all crack .. 

In the case of # 044 this consideration was not taken into account and some time after the repair all the gel crack has exposed itself .. I am sure the person who did the original repair was not aware this would happen,  but as you will see from the photo's it is quite severe. 

These cracks stop in a straight line exactly where the new section was butted up to  .. 

I have marked the worst area's , but to be fair they are not that difficult to spot .   Stress cracks are very apparent in the seams of  the 'B' and 'A' posts , both sides , but more prominent on the N/S .. 

The shell has also flexed on the o/s rear quarter with gel crack spreading all down that panel aswell . 

    

We also have flex area's in the front compartment that will need addressing, 

It also appears to have impact damage on the front that has not yet been repaired , but has split the front seam and caused extensive gel crack to the front panel . Both headlamp pods have seen better days and will need some creative reconstruction. 

  

The only other main area to cover at this point is the roof..  It has been fitted with after market sunroof , which the customer wants removing and putting back to original .. There is also some gel crack in the usual spots. 

I will cover all the other points as I go through the main shell , section by section . The panels will addressed later in the thread....    First job is to get that smashed screen and the old sunroof out ..    

Let the fun begin..   

 

 

[faye2000]

1 minute ago, CHANGES said:

SET UP and PLANNING.. 

Here we are at the start of the body restoration on JPS # 044 .. 

There is evidence it has had previous repair work, with a half rear quarter section put in ..  Unfortunately this has not been done that well and is very easy to see..   As we have said in previous threads , any impact repair on GRP has to be explored with consideration of how far the gel crack will travel .. The usual stress points along with the direct connected area will all crack .. 

In the case of # 044 this consideration was not taken into account and some time after the repair all the gel crack has exposed itself .. I am sure the person who did the original repair was not aware this would happen,  but as you will see from the photo's it is quite severe. 

These cracks stop in a straight line exactly where the new section was butted up to  .. 

I have marked the worst area's , but to be fair they are not that difficult to spot .   Stress cracks are very apparent in the seams of  the 'B' and 'A' posts , both sides , but more prominent on the N/S .. 

The shell has also flexed on the o/s rear quarter with gel crack spreading all down that panel aswell . 

    

We also have flex area's in the front compartment that will need addressing, 

It also appears to have impact damage on the front that has not yet been repaired , but has split the front seam and caused extensive gel crack to the front panel . Both headlamp pods have seen better days and will need some creative reconstruction. 

  

The only other main area to cover at this point is the roof..  It has been fitted with after market sunroof , which the customer wants removing and putting back to original .. There is also some gel crack in the usual spots. 

I will cover all the other points as I go through the main shell , section by section . The panels will addressed later in the thread....    First job is to get that smashed screen and the old sunroof out ..    

Let the fun begin..   

 

 

This rings a bell 

[Bling]

I like the analysis @CHANGES - learnt something as well

[tomcattom]

59 minutes ago, CHANGES said:

Looks like something has taken a big bite out of that head lamp pod How did it get damaged like that there?!?!

[Djs44]

1 hour ago, tomcattom said:

Looks like something has taken a big bite out of that head lamp pod How did it get damaged like that there?!?!

I think the headlights must have been up when the bonnet was open ( or similar ) as the damage has been done by the bonnet hinges ? 

And to think ,  I thought all that would polish out  

[Rudi K]

Probably a good idea to get rid of the sun-roof – it did leak from time to time. My wife found some (grainy) photos of #44 from late 1983 or thereabouts. I'm sure Dave will rise to the challenge of putting this JPS back to form…

[Erikl]

I will sleep better tonight knowing 44 is in Changes hands and he is taking the sunroof out!  Good stuff!

[Djs44]

17 hours ago, Rudi K said:

Probably a good idea to get rid of the sun-roof – it did leak from time to time. My wife found some (grainy) photos of #44 from late 1983 or thereabouts. I'm sure Dave will rise to the challenge of putting this JPS back to form…

Fantastic  to see those pictures - do you have any more info/pics ? Love the history bit 

[CHANGES]

On 07/06/2021 at 23:53, Rudi K said:

Probably a good idea to get rid of the sun-roof – it did leak from time to time.

Well it did not leak due to fitting, It was stuck in with no intensions of it ever needing removing.. The leak must have come from the seal to the glass..

Needless to say the sun roof was a real pain to get out , but with patients it eventually came free without damaging the roof .. The smashed screen was a messy job but all done and out of the way .. 

This is where we start the voyage of discovery .  As we saw from the external pics of the repaired quarter , it was looking a bit ' ify '.    So before starting to sand off the paint and gel coat , I decide to have a good look inside the section..   To my surprise there was no GRP layers at all .. 

On closer inspection the joint did not even seem to but up. In addition to that, the but faces were clean .  This means the only thing attaching the sections is a thin skin of GRP bridging the outside ..  This would explain why the repair was so visible..   Also the the imperfect panel profile .. 

Upon sanding off the paint , we encountered filler, followed by a thin GRP layer over the joint .  Very weak and poor  !!!.   What we were left with was a 5mm gap between the sections..  I decided to leave a couple of small area's not fully sanded , so the shape could be retained whilst I applied a GRP layer to the inside to re-stabilize it , before starting the next step  .

The above pic was how it started to appear when removing the surface layer .  The one below is how it appeared when all flatted out ..  It is difficult to show on a pic how clean that joint was, I did not touch it , that is how it came out ..   

I think this is a classis example of measure twice cut once .  It would seem by how parallel the cut joint is, time was taken to cut neatly , but they got the measurements wrong.. Uhmm ..      

Some nasty impact GRP crack also came to light on the new section , this will need fully grinding out .. 

 The next area to get started on is the roof ..   First job was to sand off all the paint and gel layers in preparation for filling in the sun roof hole .. 

In the above pic you can just make out the thickness of the panel, which will need recreating across the hole . 

The first task was to make a profile blank to bridge the hole , This had to fit neatly and slightly curve in both plains. 

The profile section was supported from the underside , without any vertical pressure, so as not to distort the original form.  Once happy with the fit and shape I could start grinding off a large taper area around the hole . This left a razor sharp edge where the new and old section join . 

A release wax a release agent was carefully applied to the profile so it can be removed when the new roof is formed over it .. 

When all  prepped. the new GRP layers can be applied .  I started with 1 layer the same size as the hole, then 4 more each getting progressively bigger to neutralise the taper that was ground in . Finally two full layers were applied .. 

This now needs to be left for several days to fully cure before i can continue this section .. 

Next week,  I will start to get that quarter panel back as it should be..   '' Uhmm ...loads more itchy scratchy to come ''    

[Steve4012]

Hi Dave. Very interesting as always. The black profile section underneath the sunroof hole. Did you make that as well or is it a flexible sheet that can be encouraged to form the correct roof curvature from underneath?

[drdoom]

The "repair" of the damaged body rear 1/4 as revealed by DL seems to validate that most are of the opinion, " if it ain't metal it's got no strength ". Therefore one is free as a lark to plaster away over any joint with whatever muck seems handy. Driver's door on my S2 had been dealt with in much the same manner as I discovered when sanding away at excess putty on the inside, eventually realising I'd see daylight before sound GRP. Still have the souvenir cutout dangling from a hook in the garage, largely resin in composition. Technical know-how is so vital in proper auto maintenance, no matter what the car, and I fear it's becoming scarce!

Great stuff, as always Dave.

[CHANGES]

8 hours ago, drdoom said:

The "repair" of the damaged body rear 1/4 as revealed by DL seems to validate that most are of the opinion, " if it ain't metal it's got no strength ". Therefore one is free as a lark to plaster away over any joint with whatever muck seems handy. D

This sadly is so common and as I said in the recent OOP's repair thread, once the paint is on the customer does not get to see what or how its been achieved  ..  Hopefully these threads will expose the short cuts made for profit and enable the owners to be more knowledgeable should they be unfortunate enough to need a repair . 

Acceptable methods will vary from one repair shop to another , which is why I always try to gather as many photo's for the customer whilst doing the job . They can then share the involvement and better understand what has been done and why ..     

[CHANGES]

11 hours ago, Steve4012 said:

Hi Dave. Very interesting as always. The black profile section underneath the sunroof hole. Did you make that as well or is it a flexible sheet that can be encouraged to form the correct roof curvature from underneath?

This is something that is made for the particular job..  I used sheet steel cut to the shape of the hole but 60mm wider in all directions ..  I form rolled the edges which introduces a curvature close to what is needed.. I will never be exact, but dam close .. I then used the old sunroof clamping frame from the inside to add some rigidity, whilst at the same time it refined the curvature to match the roof section .   Because the curvature is so slight when applying any downward force the steel can flex or invert the curve if pressing hard enough in the centre..   To prevent this happening when applying the GRP layers, a centre support was also fitted .. None of the supports were under tension, but positioned in a way to stop any flex and movement when being worked on ..

The aim is to get as close to the same thickness of GRP as original , but more important is to maintain a uniform thickness over the complete panel .. Slightly thicker is preferable to thinner..     

[Barrykearley]

Proper tidy job as always - that layup should never sink either in the sun like so many seem to 👍👍.

[CHANGES]

1 minute ago, Barrykearley said:

Proper tidy job as always - that layup should never sink either in the sun like so many seem to 👍👍.

Thanks ..  The reason they sink over time is usually because the profile is incorrect.. The slight upward curve acts like an Arche , so in the heat with expansion it should rise not sag ..  However this is only fully effective if the inside profile is consistent to the outside and the thickness uniform over full area..  All logical really, but maybe overlooked in some cases..   

[Erikl]

Will you add layers on the inside as well?

[Erikl]

After the steel blank is removed, I am assuming a similar build up scheme on the inside?  1st layer is same size as hole, then progressively larger layers?

 

[CHANGES]

19 hours ago, Erikl said:

After the steel blank is removed, I am assuming a similar build up scheme on the inside?  1st layer is same size as hole, then progressively larger layers?

 

 

No.  This will not be the case .   The purpose of grinding back a taper on the upper face is to replace the original thickness with as much overlap as possible for strength.. The two full layers are to create a uniform fully bonded surface .. This will need comprehensive flatting to get the smooth profile correct .. Once the flatting process and checking is done a final application of GRP will be applied with a tissue finish for refinement ..    If we did a build on the inside as the outside as you were assuming , it would massively increase the thickness and weight of the panel .  When the former is removed a light sanding will be done to smooth the joint area before fully assessing the situation .. I expect it will need no more than a layer of weave and possible a tissue layer to fully encase and bond the joint area .  I will cover this when we get to that stage ..       

[Erikl]

Tissue Layer.. Please show a pic when you get there.  Not familiar with the terminology. 

I am very curious because I have a large hole in the floor to repair and I am excited to use the same procedure (but with a large dash of amateur thrown in!)  Fortunately under the seat so not obvious.

Thanks for sharing what I am sure is decades worth of experience.  Fascinating.

 

[CHANGES]

On 14/06/2021 at 22:26, Erikl said:

Tissue Layer.. Please show a pic when you get there.  Not familiar with the terminology. 

I am very curious because I have a large hole in the floor to repair and I am excited to use the same procedure (but with a large dash of amateur thrown in!)  Fortunately under the seat so not obvious.

Its just a Type of matting used .. Here is a pic of the 3 most common i use ..  left to right .. 450 chopped strand matting,  tissue matting , weave strip . All these are applied with the resin coat , The weave us put in stress or edging area's , 450 matt for general build and repairs , tissue is for a finishing coat,  it will all become clear as the thread progresses . 

 

[CHANGES]

This week saw some more relentless sanding to remove the cracked gel coat .  Unless you have done this you can not appreciate what a Naf  job this is ..  The problem is you can not just hack at it with a grinder , it needs a certain degree of finesse. The reason being it will form the base you will be building on , so the more even it is the easier the next stage will be .. 

The grey coat  is the primer , the white the sealer coat , the pink is the gel coat , This all has to come off this shell as there is to much crack to localise sections .. When i looked at the lower section of this quarter panel I spotted two bad area's that I marked, but to the left of the top one you can see a spiders web gel crack appeared with the dust ..   Just as well I decided to do the all .. 

Apart from surface gel crack this panel was quite good . The section with the GRP layer did show deep cracks from the collision flex . These were ground out and the GRP applied . 

On the other quarter where we showed the poor cut joint,  we applied a couple of layers of the chopped matting to the inside when we did the roof ..  When this had time to cure I ground out the long taper as i did with the roof , but this time down to the new inner layer .. Then using the same progressively larger sheet of matting I filled the taper back with layers to original thickness with max strength.. 

 

The same procedure was carried out on the rear panel in the two area's where the cuts had been made..  In this case because the inside was very accessible the previous repairer had applied an inner layer , unfortunately the outer layer was mainly filler and a poor joint as the other was .. So doing the same process as other sections  we can restore the original strength while providing a quality substrate for the next layers .. 

After the roof had cured out , the former was removed from the inside .

This was then sanded back to smooth the joint . This came out absolutely spot on, but i forgot to take a 'pic' before applying the weave  tape over the joint , then a tissue layer over the whole area .. 

The inside now conforms to the original shape , it will have a light sanding when fully cured to just smooth finish ready for roof lining .. 

This week we also set about the front panel . This had a lot of gel crack with impact damage on both corners .. The seams on the front had cracked free directly behind the front of the headlamp bucket..  This area does not have an inner bridging layer and relies in the joints paste to hold it .. Hence the reason it split apart ..  I manage to to fiddle in some inner bridging layer through the indicator hole and from the front compartment , enough to hold firm whist we ground back the outside. Then in the same way as previous we applied GRP to reshape and strengthen the corner area's .. 

All of these area's done so far will need extensive sanding to establish the correct shape before the next layers are applied .. 

So next week  more sanding and dust to come  along with itchy scratchy ..       

          

[Barrykearley]

I can actually smell your garage from here.

[giorgio67]

That's is a piece of cake compared to mine...🤣

[CHANGES]

@giorgio67  You certainly seem to have a lot of fillers to deal with .. It seems the previous repairer chose not to use GRP ..  The problem with those sort of repairs is routing out the extent of the gel crack .. It will only be possible by removing all the layers in the effected area's and associated stress points then applying a stain to expose it ..  This is why on jobs like 044 i just remove all gel coat on damaged panels , it minimises any risk of crack appearing in finished repair ..    You will note i always grind back the badly effected areas, then replace with as close to the original thickness of panel as possible.  I do this to prevent sinkage or distortion that can appear later as the composites fully dry out ... This can take months and be effected by temperatures . 

Are you going to apply a GRP tissue bridging coat to seal in your repair Or just prime .. ?  

2 hours ago, giorgio67 said:

That's is a piece of cake compared to mine...🤣

They all have their challenges , maybe this is more what you had in mind.

 

 

[giorgio67]

All the repairs have been done last years, car is finished now and is amazing.