Mad4slalom
Well-known user
Well , another epic fix underway Tim , so impressed with the way you just get stuck in and get it done . 
72 Corvette - Restoration Updates
- Thread starter TimP
- Start date
Plenty more episodes to come .....
Many thanks for your kind words - which reminds me I ought to write another one. I find it really enjoyable and highly therapeutic to spend an hour or so in the workshop every day just fixing stuff - and my '72 has given me many opportunities for that . It's also good that I'm not really under time pressures (part from getting older!) to get finished. Happy days.Many thanks - much appreciated. PM sent.
Mad4slalom
Well-known user
Would love a look in mr cricket’s Corvette cave, to see his seemingly endless hoard of corvette goodies
quite a few of us have benefitted from his supply, Myself , a pr of LT 1 valve covers and numerous other bits , all at great prices and even a free nos tyre donated to make a clock. Thank you stuart
ps , still hunting for an LT1 or big block short hood . . Glad 
you are helping move Tim’s 72 along too what a great forum this is ! 
This week has been a bit busy on other things but I did manage to finish the upper patch....
I removed the top of the birdcage bow to get access to the welds for the T-Top longitudinal frame piece thingy. The bow has been acting as a collector for an awful lot of rust flakes - not surprising that there were so many holes.....
Next: to complete the lower patch which attaches to the underside of the birdcage bow...
... and then try it out for a welding dummy run although I probably won't use these weld clamps as the join is curved and the clamp is straight so the clamp pushes the pieces of metal further apart than they should.
It all seems to be going together ok at the moment (famous last words) so the next job is to unpick the spot welds on the birdcage bow and construct a new section to replace the rusty bit..... A 700mm square of 2mm steel arrived earlier this week so I think I have everything required to do this.
I also need to start thinking about how this all goes back together as the positioning and sequencing of the puddle welds is going to be important as I don't want to do any welding up side down....(is it even possible?)
I removed the top of the birdcage bow to get access to the welds for the T-Top longitudinal frame piece thingy. The bow has been acting as a collector for an awful lot of rust flakes - not surprising that there were so many holes.....
Next: to complete the lower patch which attaches to the underside of the birdcage bow...
... and then try it out for a welding dummy run although I probably won't use these weld clamps as the join is curved and the clamp is straight so the clamp pushes the pieces of metal further apart than they should.
It all seems to be going together ok at the moment (famous last words) so the next job is to unpick the spot welds on the birdcage bow and construct a new section to replace the rusty bit..... A 700mm square of 2mm steel arrived earlier this week so I think I have everything required to do this.
I also need to start thinking about how this all goes back together as the positioning and sequencing of the puddle welds is going to be important as I don't want to do any welding up side down....(is it even possible?)
Mad4slalom
Well-known user
Blimey! It's been nearly three months since I last posted on this - how time flies.
When I first started the work on the rear bow I think I said it was going to be tricky but that turned out to be a complete under estimation of the task in hand. It was really hard and when you look at the photographs which look like a nice process from A to Z, please spare a thought for the number of interactions where it went wrong and I started again. The main U-shape that forms the strengthener for the bow is shown here in its third iteration. I also don't show that the number of times the glass fibre section that I cut out was refitted to ensure that it was going to fit back on again when everything was done.
So, carrying on the sequence from last time...here is the lower patch being trial fitted with the existing U-section (at the rear) but with a new front section.
This lower patch was then welded in place to form a platform for the top patch assy that I had fabricated earlier...
I decided to brace the butt weld with a 'bonding strip' reinforcement
.... which was then plus welded in place and coated with weld-thru primer
This upper patch was then welded in place ....
.. and then the old u-section was removed (as was the jig that was holding everything together originally)
Then a new u-section was fabricated... this its bowed so had to be (third time lucky) made up from scratch. The first two iterations were made originally from 1 inch square section bent to shape over a wooden former. These looked perfect to start with but when these were welded in place the residual stresses made their presence felt and the heat of the welding straightened them out again. You live and learn......
Here is the old and new u-section on the bench for comparison...
... carrying on this post in a minute ....
When I first started the work on the rear bow I think I said it was going to be tricky but that turned out to be a complete under estimation of the task in hand. It was really hard and when you look at the photographs which look like a nice process from A to Z, please spare a thought for the number of interactions where it went wrong and I started again. The main U-shape that forms the strengthener for the bow is shown here in its third iteration. I also don't show that the number of times the glass fibre section that I cut out was refitted to ensure that it was going to fit back on again when everything was done.
So, carrying on the sequence from last time...here is the lower patch being trial fitted with the existing U-section (at the rear) but with a new front section.
This lower patch was then welded in place to form a platform for the top patch assy that I had fabricated earlier...
I decided to brace the butt weld with a 'bonding strip' reinforcement
.... which was then plus welded in place and coated with weld-thru primer
This upper patch was then welded in place ....
.. and then the old u-section was removed (as was the jig that was holding everything together originally)
Then a new u-section was fabricated... this its bowed so had to be (third time lucky) made up from scratch. The first two iterations were made originally from 1 inch square section bent to shape over a wooden former. These looked perfect to start with but when these were welded in place the residual stresses made their presence felt and the heat of the welding straightened them out again. You live and learn......
Here is the old and new u-section on the bench for comparison...
... carrying on this post in a minute ....
Attachments
..... Once again coating everything with primer...
Then seam-sealing the inside with er.... seam sealer.
... and then welding the top section on and after grinding the welds smooth...
.. and with a coat of etch primer.
It's not quite as it left the factory but it is strong, functions as it should and everything (at this stage, he adds carefully) seems to fit. Incidentally there was one oddity on the bow section: on my car the 'width' of the bow (front to back) was 5 mm less on the passenger side than it was on the driver's. I had assumed originally that it would be the. same dimension all the way along but it actually tapered quite a bit - just under 10% of the width. Whether they are all like that or whether this was just the hand built nature of the car I don't know. Its was one of the reasons why I had to start fabricating some of the pieces again, once this was realised.
All that needs to be done now is to apply two coats of epoxy primer, drill a hole in the top and fill the inside with Dinitrol or something similar (this car isn't going to rust again if I can help it) and then re-bond the missing glass fibre section.
I'm glad to say that this is the last piece of the birdcage that needed to be redone so that's now all behind me. Next, I need to replace all the bits that have been removed to make sure that everything fits and work, and then remove the body and do all the bits (fuel and brake lines etc) that are beneath.
Onwards and upwards....
Then seam-sealing the inside with er.... seam sealer.
... and then welding the top section on and after grinding the welds smooth...
.. and with a coat of etch primer.
It's not quite as it left the factory but it is strong, functions as it should and everything (at this stage, he adds carefully) seems to fit. Incidentally there was one oddity on the bow section: on my car the 'width' of the bow (front to back) was 5 mm less on the passenger side than it was on the driver's. I had assumed originally that it would be the. same dimension all the way along but it actually tapered quite a bit - just under 10% of the width. Whether they are all like that or whether this was just the hand built nature of the car I don't know. Its was one of the reasons why I had to start fabricating some of the pieces again, once this was realised.
All that needs to be done now is to apply two coats of epoxy primer, drill a hole in the top and fill the inside with Dinitrol or something similar (this car isn't going to rust again if I can help it) and then re-bond the missing glass fibre section.
I'm glad to say that this is the last piece of the birdcage that needed to be redone so that's now all behind me. Next, I need to replace all the bits that have been removed to make sure that everything fits and work, and then remove the body and do all the bits (fuel and brake lines etc) that are beneath.
Onwards and upwards....
Attachments
I forgot to mention in the last update that I had also bonded in two 4 x 1and a 1/4 inch painted steel plates to help brace the butt welds at either end of the bow. I used the same 3M marine bonding adhesive that I used to rebuild the glass fibre front end of the car and to bond it to the birdcage. It's pretty strong stuff - quite a bit stronger than Tiger Seal - and although its probably not necessary, it doesn't do any harm to give the bow welds some extra reinforcement.
There are two bolts on each side of the bow on the inside that secure the castings for (I think) the rear T-Top clamps. Unfortunately during strip down all four bolts had declined a polite offer to be removed and had to be drilled out leaving four stubs to be extracted. Welding a bolt to each of the stubs heading allowed me to get some purchase on them and I expect the added heat of welding helped break the threads....
The piece of glass fibre 'roof' that I cut out was given a given a quick test fit....
..... prior to preparing each end of that section and the sides of the roof where it was going to be joined. Using an electric file I thinned down the glass fibre as much as I dared (from 3mm to about 1mm) to allow for approx 3 inches width of new glass fibre to be let in. The old section was then bonded in place with Tiger Seal across the top of the steel bow and held in place with a fairly Heath Robinson arrangement to make sure that it was properly positioned whilst the adhesive went off.....
... and then this section was glassed in place. Cling film was used as a release agent and then some weight placed on top to give some better shape to the fresh glass fibre. There is a also a length of 25mm box section clamped in place to give the leading edge approximately the right profile...
... and then after it had gone off each side (driver's side shown here) was trimmed down with a selection of files, a DA sander, and a sanding block.
The underside has been glassed in too, in the same way although I haven't got round to sanding that down yet. Hopefully, by the time I have finished it should be difficult to tell that this section was ever removed - that's my intention anyway. The joins will need a thin skim of filler when the body work is in pre-paint and there are a few areas around some of the pre-drilled holes that need to be repaired.
It took about 3 months to get this section of the bird cage done and I am glad to have it behind me (figuratively and literally) now. Come to think of it, this marks the end (fingers crossed) of all the birdcage restoration so a major milestone I suppose.
After a fairly intense clean - there is dust everywhere - I will test fit the rear window ( '72 was the last year of the removable window), all the trim and brackets that join to the bow and make sure everything goes together nicely before putting those bits back in the box and moving focus on to the engine/transmission.
There are two bolts on each side of the bow on the inside that secure the castings for (I think) the rear T-Top clamps. Unfortunately during strip down all four bolts had declined a polite offer to be removed and had to be drilled out leaving four stubs to be extracted. Welding a bolt to each of the stubs heading allowed me to get some purchase on them and I expect the added heat of welding helped break the threads....
The piece of glass fibre 'roof' that I cut out was given a given a quick test fit....
..... prior to preparing each end of that section and the sides of the roof where it was going to be joined. Using an electric file I thinned down the glass fibre as much as I dared (from 3mm to about 1mm) to allow for approx 3 inches width of new glass fibre to be let in. The old section was then bonded in place with Tiger Seal across the top of the steel bow and held in place with a fairly Heath Robinson arrangement to make sure that it was properly positioned whilst the adhesive went off.....
... and then this section was glassed in place. Cling film was used as a release agent and then some weight placed on top to give some better shape to the fresh glass fibre. There is a also a length of 25mm box section clamped in place to give the leading edge approximately the right profile...
... and then after it had gone off each side (driver's side shown here) was trimmed down with a selection of files, a DA sander, and a sanding block.
The underside has been glassed in too, in the same way although I haven't got round to sanding that down yet. Hopefully, by the time I have finished it should be difficult to tell that this section was ever removed - that's my intention anyway. The joins will need a thin skim of filler when the body work is in pre-paint and there are a few areas around some of the pre-drilled holes that need to be repaired.
It took about 3 months to get this section of the bird cage done and I am glad to have it behind me (figuratively and literally) now. Come to think of it, this marks the end (fingers crossed) of all the birdcage restoration so a major milestone I suppose.
After a fairly intense clean - there is dust everywhere - I will test fit the rear window ( '72 was the last year of the removable window), all the trim and brackets that join to the bow and make sure everything goes together nicely before putting those bits back in the box and moving focus on to the engine/transmission.
I had hoped to be able to say in this latest post that I had been working on the engine and it's all working just fine...... but I really wanted to get the car outside before trying to get it started and we just haven't had the weather (not down south here anyway) to do that.
So I decided to carry on with the bodywork. Before finishing the bow glass fibre I needed to refit one of the reinforcement plates that hold on the T-Top brackets. The bolts that fix the bracket in place had seized and there was no other way to get them off other than to drill out the rivets and let it fall out the bottom of the bow glass fibre.
Inspecting the plate confirmed that a new one was required (as can be seen from the pic) so a new one was made up, painted and then threaded up the same glassfibre that it came out from and then riveted in place (holes at the top of the photo). The rivets are slightly oversize and needed to be shaped to fit.
Originally I thought I was going to have to cut another hole in the bow to get this bracket in but by drilling a small hole in the end of the plate and hot glueing a piece of stiff wire into it I was able to push the plate to the right place, put a couple of bolts in to secure it in position and then tug on the wire to free it from the plate. Then the plate was riveted in place. It turned out a lot easier than I thought.
So I decided to carry on with the bodywork. Before finishing the bow glass fibre I needed to refit one of the reinforcement plates that hold on the T-Top brackets. The bolts that fix the bracket in place had seized and there was no other way to get them off other than to drill out the rivets and let it fall out the bottom of the bow glass fibre.
Inspecting the plate confirmed that a new one was required (as can be seen from the pic) so a new one was made up, painted and then threaded up the same glassfibre that it came out from and then riveted in place (holes at the top of the photo). The rivets are slightly oversize and needed to be shaped to fit.
Originally I thought I was going to have to cut another hole in the bow to get this bracket in but by drilling a small hole in the end of the plate and hot glueing a piece of stiff wire into it I was able to push the plate to the right place, put a couple of bolts in to secure it in position and then tug on the wire to free it from the plate. Then the plate was riveted in place. It turned out a lot easier than I thought.
Next thing to do was to finish the bow glass fibre and give it a coat of protective epoxy primer. Starting with glazing putty top and bottom ...
Then repairing the holes that help align the chrome T-Top trim which were all damaged....
After multiple iterations of fill, sand, inspect, repeat.... two coats of epoxy primer were rolled on. This is to protect the original glass fibre and prevent any dampness from getting into the original (somewhat hygroscopic) finish.
The eagle eyed will notice that a door has been fitted - progress! The rest of the old paint has been stripped from the back of the car and the next job is to finish off the primer all over the rear. More soon.....
Then repairing the holes that help align the chrome T-Top trim which were all damaged....
After multiple iterations of fill, sand, inspect, repeat.... two coats of epoxy primer were rolled on. This is to protect the original glass fibre and prevent any dampness from getting into the original (somewhat hygroscopic) finish.
The eagle eyed will notice that a door has been fitted - progress! The rest of the old paint has been stripped from the back of the car and the next job is to finish off the primer all over the rear. More soon.....
Attachments
Mr. Cricket
Committee Member
Sorry Mad I hadn't seen this post and your Vette is looking very close to an LT-1 set up now!Would love a look in mr cricket’s Corvette cave, to see his seemingly endless hoard of corvette goodies
Myself , a pr of LT 1 valve covers and numerous other bits , all at great prices and even a free nos tyre donated to make a clock. Thank you stuart
Having just seen Tim's new post and the progress made I'll get the goodies I have to one side for him over to him asap as I'm in to the last stages of completing the Corvette cave so I need to clear out stuff and organise the last few bits. I NEED to get rid of 3 x 6' x 3' glass display cabinets that came with 178 model Corvette collection I purchased but they don't work for me so they're in the way and need a new home FOC
Mad4slalom
Well-known user
happy new year
Mad4slalom
Well-known user
Yes - it's beginning to take shape! I have promised the organiser of our local car show that I will have it on the road for the next event in July so I'd better get a move on.
Many thanks - you are too kind....Absolutely fenom , phenhom , fernom in ,…..…
“BRILLIANT “ work Tim
johng
CCCUK Member
When in July? Hopefully it won't clash with the Nationals, as I'm sure there are plenty of us keen to see it there.Yes - it's beginning to take shape! I have promised the organiser of our local car show that I will have it on the road for the next event in July so I'd better get a move on.
Mr. Cricket
Committee Member
It's a MUST that Tim brings it to the Nationals
CCCUK Corvette Nationals 19th & 20th July 2025 Sywell Aerodrome
As mentioned in the latest Vette News, we have booked Sywell again for 2025 following this years successful and sunny event so please put it in your diary for next year. Accommodation at the Aviator hotel on site is fully blocked for the weekend so please don't try to book until we notify...
www.corvetteclub.org.uk
Much as I would like to, that's a bit of a stretch! It's a 300 mile round trip for me and I need to get some shakedown miles in to make sure that everything is working as it should, safely and reliably. 2026 definitely but let's see.......