73 MGB GT restoration

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Hazza1190
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Forename: Harry
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73 MGB GT restoration

Post by Hazza1190 » Mon Jan 07, 2019 2:31 pm

Afternoon all,

I have finally got somewhere to store my MGB GT which means I can begin the restoration. I am going to first start with the exterior as it has had a pretty dreadful respray at some point in its life so a lot of paint is damaged or very bad quality. There are also a few patches of surface rust that need to be sorted, hopefully nothing too substantial.

I will firstly start by removing all the exterior bits and bobs (Chrome bumpers, door handles, grill, chrome trim etc etc) so that i can get a good look at it. It will have to go back to bare metal as i simply don't trust any of the paint on the car, i have a feeling it will cause problems in the future if i paint over it. I would like to do remove the paint myself so that i dont have to pay the re-sprayers to do it, but unsure of the best way to go about doing this? I thought about paint stripper, but its far from a delicate procedure and worried that it will cause more trouble than good? The main benefits to it though are that its easy, and wont damage the metal underneath (scratch it up for example). What other methods are there to remove all of the paint?

Has anyone got any good info or tips for a restoration? As its beginning to look like quite the experience!!!

I also want to put the car up on axle stands so that i can work on the underside of the car. It has way too much under-seal thats been carelessly sprayed on that i want to scrape off. Im a bit worried to do this as i have heard that when the car is on 4 axle stands it can become unstable and easily topple over. Any ideas for a safe way to do this?

Thanks,
Harry.
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Peter Cresswell
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Location: Stone, Staffordshire

Re: 73 MGB GT restoration

Post by Peter Cresswell » Tue Jan 08, 2019 2:25 pm

Hi Harry
As a starter I would suggest you get hold of the MGB Restoration Manual by Lindsay Porter, published by Haynes. As the title suggests this covers all aspects of restoring the MGB, and it is better than the workshop manual as it tells you how to repair parts and components which the workshop manuals invariably don't cover.
As far as stripping the paint off the car it is entirely possible to do it yourself at home, but it takes a long time and is a very messy process. You need hand and rotary wire and/or nylon brushes plus copious amounts of paint stripper. For this reason many people will take the car to a professional and get it soda blasted. You can hire soda blaster and do it yourself at home but again it is a messy process. Ideally you need the car to be completely stripped down to a bare shell for doing this, and remember that whether you opt for the diy approach or professional the bare metal will go rusty very quickly - within the hour you will see rust starting to form! If you are going to all the trouble of a bare metal respray you really should think about spraying the whole shell and the only way to do this is a complete strip down.

This site will give you an idea of the costs involved. http://www.thepaintshoppros.co.uk/hire- ... paint-car/

As far as working underneath the car whilst it is on axle stands, yes you do need to be very careful, and it is probably better to lower the car onto 4 car ramps as these are much more secure. If you do use axle stands, make sure the (usually) three feet of each stand is firmly on the ground as they tend to tilt slightly as the car is lowered onto the stands, especially if you only have one jack and have to jack up a lower onto the stands one end at a time. Before going underneath, give the car a good push sideways. If it is going to fall off the stands it is better to have this happen when you are not under the car. Remember as well that you will be scraping off the underseal just a few inches above your own body!!
Pete
1969 MGB Roadster
2002 MG TF 135 (Now sold and joining the previous 8 MGs I have owned)
2011 MG 6 TSE Magnette
2002 Toyota MR2 Roadster
2007 Mercedes SLK
Ian Fozzard
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Re: 73 MGB GT restoration

Post by Ian Fozzard » Tue Jan 08, 2019 3:08 pm

Hi Harry,
good advice from Peter which I endorse (as usual!), here are some of my thoughts which you may wish to consider:
# if you are thinking of a full professional respray then stripping down to bare metal would be worthwhile, but if (like me) you are doing a home repaint job then I wouldn't say bare metal is necessarily the best starting point. I would rub down with coarse wet and dry and plenty of water. Try some professional grade 120 grit with a sanding block and plenty of water and a little pure soap flakes for lubrication.Indasa Rhynowet is good quality paper - infinitely better than some of the stuff that the high street chains will sell you. This avoids a lot of dust and produces an inert waste, unlike paint stripper. You will probably find the original paint and filled areas, and rusty bits, and you can deal with each as it requires. If you use paint stripper this will damage any areas of filler which have been used and necessitate a lot of work which may be really unnecessary (if filler has been well aplied to a sound metal surface there should be no reason to remove it all).

# First job for me though would be to get under the car, remove that underseal and make absolutely certain that you have no structural issues to deal with. As you may know the MGB sills are complex double box section affairs which extend under both the front and the rear wings. If you find any significant corrosion you should be removing the front wings to do a full inspection and repair as necessary. You should ensure that the structure is perfectly sound before contemplating any repainting of the upper bodyshell.

# for supporting the car I would agree with Peter that ramps are safer than axle stands, but you ideally need to have the wheels off the car so that you have full access to all of the underbody area. I use a sturdy pair of axle stands widely spaced on the back axle, and a further pair adjacent to the bases of the front wishbones. As an insurance measure I have some large sections of timber which I place under the car across the chassis or wherever required which would prevent the car falling far if it did come off the stands. These can be moved around as required to allow access as you work around the car.

# It is possible to respray yourself using cellulose paint, which can still be legally purchased for classic car painting. This paint is probably not as good as cellulose was back when in common use, but it's not advisable to attempt to use any 2 pack paints without full professional equipment and training. If you are stripping the bodyshell yourself of course you will have to consider applying some paint to prevent rusting of bare metal even if you are getting a professional to apply the colour coats. Acid etch primer would be my choice for this job, after you have removed all rust or welded in new metal if required. If you have an autopaint motor factor near you it would be well worth going in for a chat and asking their advice on what materials and equipment they would be able to recommend and supply (again, best to avoid that well known high street chain for a big job like you are planning).

Hope this might be some help,

Ian F.[attachment=0]L1050264e.jpg[/attachment]
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Hazza1190
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Forename: Harry
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Re: 73 MGB GT restoration

Post by Hazza1190 » Wed Jan 09, 2019 3:32 pm

Hi Both,

Thank you for the very useful replies!

Peter:
I actually think i have the MGB Restoration Manual by Lindsay Porter at home so i will definitely be giving that one a read!

I think one of the main issues with the previous paint job was to do with the prep, as the paint just doesn't seem to have correctly stuck to the metal (this is mainly a problem on the drivers rear wing, drivers door and bonnet). I may be able to just rub down the rest without stripping it entirely.

The 'garage' floor, unfortunately, isn't very flat so that is what makes me most nervous. I am sure that i can make it flat enough, but due to this i am going to be super careful when it comes to going under the car, mainly but putting large cinder-blocks under the car, and as suggested, keeping 1 end on ramps instead of all 4 corners on axle-stands.

Ian:
Im pretty sure im going to go down the sanding method, but may have to completely strip both the door and the bonnet as these are the worst panels. As you mentioned, it's a good idea to preserve any filler to for ease. I have been round the car with a magnet and sock and cant find any substantial areas of filler which is a good sign.

Im pretty sure the car is pretty structurally sound, as i cant really see any rust on the car. It has had the sills and front wings done at some point, but unfortunately the car was a barn find with absolutely no history, so there is no way to tell when this was done. They weren't done amazingly neatly, but they seem to be pretty sound so i think i will leave them as are as i cant see any rust. The only problems are with the front wing baffle plate mountings, they are damaged i believe so they don't seem to mount the baffle plates properly so i need to get them looked at.

I love your Idea of respraying the car myself, not only because it will be a lot cheaper, but it will be a great skill to learn. Even if i completely mess it up and end up having to get someone to do it, i wont have lost much money in giving it a go. Is the image attached one that you have done? If so, do you have any good tip's/information or articles that helped you do it?
Are you able to get a good shine on cellulose paints? I will most likely add a ceramic coating over that too if it doesn't react with it.

Thanks again!
Harry.
Ian Fozzard
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Forename: Ian
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Re: 73 MGB GT restoration

Post by Ian Fozzard » Wed Jan 09, 2019 5:31 pm

Hi Harry,
one important thing first - I would advise very strongly against using cinder blocks/bricks/stone/concrete as your supplementary car supports! These all can (and have done) crumble very easily when a load is applied - can be lethal. Get some big bits of timber - railway sleeoer size - these definitely will not crumble or crack.

Yes, that's my MGBGT which I had just finished spraying with cellulose in my garage. There is such a lot of advice and information to impart on using cellulose I would find it difficult to know where to start! Whereabouts are you? Probably not close enough to where I am to speak directly I suspect?

Just a few points to start with:
# cellulose paint is usable for a home respray but does still present hazards and you must be aware of these before starting. The solvents are hazardous to health (yours and your neighbours!) and are explosive if allowed to accumulate in a closed space. The paint mist is also not something your neighbours will want to be expsed to.
# it is a very forgiving material to use, can be polished to a brilliant shine after application, and can be retouched very easily (because it is solvent bourne any fresh application blends in easily. However, compared to two pack paints it is brittle and will chip fairly easily - touching up stone chips is an annual task.
# as a minimum you would need to invest in a reasonably sized compressor, a water separator, hoses and a spray gun - your local autopaint factor could advise. I also find a small airbrush very handy for repairs to small areas. You would also need an organic vapour respirator, some nitrile gloves, and a visor or goggles to protect your eyes. Then you would need to have a bit of a practice before anything more committing!
# for the paint I would recommend an acid etch primer, then primer/filler, then cellulose gloss. If you need to fill any deeper areas the Plastic Padding Professional filler is the material I would use (flexible so does not crack). UPOL can provide most of the paint materials except the colour coats, for these I have used cellulose paint from Paints4U or Jawel. If you can supply the Colour Code (Teal Blue is BLVC 18) then they should be able to mix the colour for you. Get good quality thinner for the paint - standard cellulose thinner will not suffice for spraying - it is usually recovered solvent and can contain lots of things including water.

That's probably enough for now, but I can help as much as required if you decide to go down this route for the job,

Ian F
Hazza1190
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Re: 73 MGB GT restoration

Post by Hazza1190 » Tue Jan 15, 2019 11:25 am

Hi Ian,

Ahh yes that's true! I definitely wont be using any concrete type blocks!

I live in Mid-Devon so i suspect that we may be a ways away from one-another! I will try and do as much research on the matter over the next few weeks as i have only started dismantling the car last weekend!

Luckily my garage is situated over in the field across the way from my house, meaning that it shouldn't make it anywhere near to the house which is good! I will definitely make sure to take all the necessary precautions when spraying as i know its not great for your health!
Thank you for all the other information, it will all come in very handy when it comes time to start the paint prep and spraying! It's a long way off yet but exciting nevertheless!

Kind Regards,
Harry.
Hazza1190
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Forename: Harry
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Re: 73 MGB GT restoration

Post by Hazza1190 » Tue Jan 22, 2019 11:59 am

Hi Ian,

I have stripped away the majority of the exterior chrome, lights, trim etc now and ready to begin the prep stage.
A few more questions if you dont mind me asking you!

I was thinking of using an orbital sander to do the preliminary 'rough' sanding. Is this something that you used on your car, or was it all elbow grease and sweat?
What would be your recommendations on the first grit of sandpaper, there seems to be a lot of deviation from search results, some suggesting 80 grit all the way through to starting on 500 grit.

Im not too sure whether to take off the front wings for repair, as the beading between the wings and the rest of the car are a bit messy. However, they dont look rusty, maybe just some surface rust. If i don't remove the wings, do you have any ideas on how to neaten them up so that they look correct, as im not too sure how to correctly sand the edges without distorting the shape of the beads (i hope that makes sense). If its easier i will get some photos of the condition of them?

I will be removing the front windscreen as the mouldings are a bit knackered, i have researched this so not too worried about it. However the rear looks fine, and i will be keeping it in-place during the respray. Is this a bad idea, as im not too sure how the edge between the moulding and the new paint will look?

Finally, i need to re-paint the radiator, any suggestions on the correct black paint to do so?

Thank you very much for your help!

Kind Regards,
Harry.
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Peter Cresswell
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Location: Stone, Staffordshire

Re: 73 MGB GT restoration

Post by Peter Cresswell » Tue Jan 22, 2019 8:43 pm

Hi Harry,
If you are taking the front screen out you should read the advice here: http://www.mgb-stuff.org.uk/bodytext.htm#screen

It not quite as easy as it looks! Even Ed China got a professional in to fit the screen on the GT they tarted up!
Pete
1969 MGB Roadster
2002 MG TF 135 (Now sold and joining the previous 8 MGs I have owned)
2011 MG 6 TSE Magnette
2002 Toyota MR2 Roadster
2007 Mercedes SLK
Ian Fozzard
Posts: 137
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: Fozzard

Re: 73 MGB GT restoration

Post by Ian Fozzard » Wed Jan 23, 2019 11:19 am

Morning Harry,
here are some of my thoughts on what you've asked, based on my experience, so other folk on this forum may want to contribute their views which may differ from mine! I will send you a PM with my phone number so that you can call me for a chat about anything if you might find that useful.

# Orbital sanders - I wouldn't use one of these unless you are taking the bit you are working on back to bare metal. One of the most difficult things to achieve is a nice smooth surface with no undulations or unevenness - these will really show up if you manage to get a good shine on the finished paintwork. For this reason I would recommend a sanding block (you may need several sizes) with wet and dry paper. This keeps the surface nice and flat and even. With good quality paper of the correct grit you will be surprised at how quickly the paint comes off!
# As a check on the previous bodywork I would suggest taking the paint off down in the lower part of the rear wing, just behind the bottom of the door. This part of the rear wing has to be removed to do the sills properly - the sills extend behind the rear wing. You can then make sure that the job has been done properly, see the quality of the welding etc. If this panel has not been cut out and replaced then it probably means that either the whole wing has been replaced or the sills have not been repaired properly. You could use an orbital sander or any mechanical device to get the paint off in this area to check the metal work.
# For grit size and a sanding block I think it depends on how much paint you think there is to remove. Ideally it would be good to get down to the original primer with just that left on the metal if it is in good condition. Of course you will be very lucky to achieve that all over the car. If you suspect that there is just single layers of primer/filler/top coat then I would use 240 grit and go carefully. If you suspect there there are multiple layers of paint (not unusual in these cars) then you would want to remove most of it and perhaps start off with 120 grit. You really need to check the recommendations of the paint manufacturer for advice on what the final grit should be - you will probably find that each paint has a specific recommendation for the final sanding before applying the paint. Rubbing down between coats and final finishing of cellulose I use a progression of sizes down through 400 - 800 -1200 followed by polishing compound such as one of the Farecla products (G3 is good).
# For the front wings - if you are doing a job of this size then I would definitely take them off. The junction between the wing and the scuttle panel is prone to corrosion and you can't sort this out unless you take the wings off to get below the joint. Once removed you can do a thorough job on both the wings and the scuttle panel. It will also allow you to check the front ends of the sills and all of the other metalwork under there to make sure it is all sound and properly repaired.
# Similar considerations for the windscreen - if you can see any corrosion around it you really need to take the screen out to remedy it. As Peter says it is a bit tricky but I managed to get mine out and back in again with a bit of care. I did have to replace all of the original chrome trim though as it distorted as I took it out and wasn't really re-usable. I used the string technique to get the rubber back in place and made a flat 90 degree hook device to get the chrome trim back in!
The rear tailgate does not seem to suffer so much from corrosion around around the glass and I didn't take that out. To respray with glass in place you need to work a long piece of string all around the outer edge of the rubber to lift it clear of the metal, and then use masking tape on the rubber and the whole of the glass. Doing this you can spray right under the rubber and there will be no edge visible when you remove the string and put the rubber back in place.
# for the radiator I would say any semi-matt finish paint would suffice - your paint factor will be able to supply a suitable aerosol.

As a final thing - here is a link to a website you may find helpful:

https://www.mig-welding.co.uk/spray-painting.htm

Hope this is usefull,

Ian F.
Hazza1190
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Forename: Harry
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Re: 73 MGB GT restoration

Post by Hazza1190 » Mon Feb 11, 2019 5:13 pm

Hi Ian,

Sorry for the belated reply, i have been a bit busy of late!

Again, you have been extremely helpful with your fantastic information, so thank you very much!!!

I think i will try to avoid the orbital sander then and will just do it all by hand, will probably end up with muscly arms by the end of it haha! In regards to the sanding block that you used, i purchased a rubber block from Screwfix along with some 120 grit wet and dry sandpaper as i need to remove quite a lot of paint from a few areas. The rubber block was actually very hard and didn't have much give in it at all. Is that correct, or should i try find something with more give as i can't see how to get a good finish on parts of the body with a heavy curve on them (like the wings for example)? May i ask what sanding blocks you used?

I have recently stripped back some of the paintwork and have fount a bad repair on one of the sills. It will definitely need a new outer sill on one side, but not too sure about the other. If the sill is rotten inside too then i will try to do the entire sill replacement myself. Ive not had much experience with this myself but I am quite a good learner and think i have the capability to do the job myself. I have a welder at home so will get some practice in with that first, maybe attend a few welding classes. If its just the outer sill then that will make the job somewhat easier. Is this something that you have any experience in?
The rear wings look in good condition, i also believe that the entire rear wing has been replaced at some point too (not just the small repair section).

I will definitely remove the front wings, they are in perfect condition, the look brand new yo be honest, so think they may have been replaced more recently.

I am definitely not looking forward to the front windscreen, but it definitely has to be taken out as the rubber seal is in a sorry state so almost at the end of its life, From what i can see, no water has gotten past it yet so im pretty confident that there is no rust.

Thats a great tip for the rear windscreen seal, using the string to move it out the way; i will most definitely be using that technique!!

Thanks again!
Kind Regards,
Harry.
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