My 1973 TVR 2500M : Renew and Restomod

TurnerX19 said:

In reply to TVR Scott :

I must say it took several years for the Vixen to show the print thru, and it is probably amplified by the metallic feces brown color. I will try to get a photo of it next time I am working there on his Jag Mk2.

Metallic feces brown.  Lovely.

That will not be my choice of color.  I'm going for metallic urine yellow.

Not actually.

You do wonder who picked the color palette for some of these sports cars. Seriously these are two seater limited production sports cars,  that does not mean they all have to be Ferrari Red or Fly Yellow but not a lot of creativity here. It looks like from this paint chart, that TVR Silver Bronze is the actual name, but I really like Metallic Feces Brown,  wonder what the local PPG dealer would say if you asked for the paint code for it 

In reply to dherr (Forum Supporter) :

I like that the paint system is Gipgloss.  Like it couldn't get any weirder.  I'd better not show my younger daughter the Silvery Green color - she's been campaigning for BRG for years.

All this print-thru business has totally settled my mind away from farming out an expensive paint job.  I'll either paint it myself or wrap it, but no way I'm going to spring for a 5-figure spray only to have it print thru a few years later.

I'm a sucker for maroon over beige/tan/brown interiors, so I had to look up the burgundy. glad I did! I'm not sure if it's the right color or not.. but maybe it should be.

reference link: https://www.rcnmag.com/fresh-finds/solid-buy-1974-tvr-2500m

I vote funky green and tan. 

I love green cars 

I really had decided to stay with blue, leaning toward Land Rover Arles or Marine Blue.  Now I'm back in the BRG camp, but that just narrows it down to about a dozen choices.  Leaning toward one of the Triumph TR6 greens from the mid-'70s. One of the lighter, "creamier" British Racing Greens.  I'll have to research what it's called.  NOT Java Green, by the way.

I know it's a Taimar, but I think that color just looks right with the car's styling.  Personally, I thnk the car looks better with the chrome air vents and NACA ducts, but I would like to have the hatchback!

I have to say I am glad my customer does not frequent this board. He absolutely loves the color on his Vixen. I love the car, but it would get a paint brush before I parked it in front of my house.

In reply to Stu Lasswell :

That's a good looking car.  I'm not painting mine green, but I do love that look.  Don't show Lucy that pic though!

I like the burgundy too, though I swore I wouldn't paint this car red.  My last three cars/truck have been red, and the girls have promised a general strike.  I still might paint it red...

I did a bit more work this afternoon.  For crack-dye, I picked up some resin dye and mixed it with acetone:

Smeared it on:

After a few minutes, I wiped that off with clean acetone and got this:

Oh my lord.  I know what I'm doing for my winter vacation...

I do like how the dye makes the crack depth very obvious.  You can really see it here:

I also beveled the edge around the "carb-hole" cut in the hood.  That'll be my first lay-up on the hood, and will let me verify my technique and confirm all the materials play well together.

I ripped off the PO's fiberglass "reinforcements".  Ripped them off by hand.  Awesome.

And I removed the screens over the NACA ducts.  I won't need the screens there and they were pretty restrictive.

That's it for now.  Thanks everyone for chiming in on the colors and stuff.

When I am faced with something with that volume of cracks so closely spaced, I do a general all over deep sanding, just shallow enough for the part to retain shape. I then rebuild with strong glass on the exterior, but I don't finish it yet. Then I go to the inside and repeat the deep sanding until I reach new material. Rebuild the inside to necessary thickness. Go back to the outside and finish fully for prime & paint. Much less time consuming than chasing the individuals, and you don't have remnants of the brittle stuff interspersed with good glass. Also, given your mold making ability, the idea of a quick, not time durable refinish to use as a positive buck to facilitate mold building might make economic sense. Not likely to yield a useable part any sooner than my rebuild technique, but you sure could sell a few.

In reply to TurnerX19 :

Yeah, part of me wants to clean it up and make a mold.  I know a hood that I made would be both much stronger and much lighter.

The other part of me has no clue how I could make a mold that big and do proper layups in my overly cramped garage.  It would be a fairly complex mold too.  Would likely need to be at least two pieces to accomodate the overhang on the front end.

For selling them, some people would want the hood and side vents, and some wouldn't.  Marker light locations on the side change over time too.  Not sure I even know how to chase all the different options for different model years.  And then there's the frame bonded in the front.  I have visions of charging someone $10K for a fresh hood.  Seems crazy yet not unrealistic.

My knowledge of fiberglass dates back to the early 80s and was limited to model sail boats, so I'm way out of my depth here.  One project that has been waiting for me to get the itch (bad pun intended) is refinishing an old M class model sail boat that my brother and I built in 1980.  It has a wood structure with a fiberglass covering.  That's all banged up, so I was planning to do a veil coat of fiberglass over the entire hull after sanding the existing fiberglass to a rough finish.  Fortunately we didn't lay up a resin-rich finish coat, but there are still similar considerations such as adhesion and dissimilar materials (I have no recollection what resin we used).  It also needs to not sink.

I was wondering whether laying up a veil coat over the entire hood would work.  If it adheres properly, it would at least reduce print thru and firm up the cracking.  Achieving a paintable surface after that may not be the most fun job ever.

As for color, that dark burgundy looks nice.  Or a darker blue like your dye material.  I mostly agree about the green, but that looks good as well.  For some reason, TVRs look better in darker colors to me.  Otherwise I'd suggest Healey Ice Blue.

In reply to JoeTR6 :

That sail boat sounds like a ton of work.  I'm guessing you probably used polyester resin, since it's the most common.  I've had very good luck with epoxy sticking tenaciously to any well-prepped surface.

I tend to prefer the lighter colors on these cars, and I like Tim Suddard's reasoning on painting small cars bright eye-catching colors.  He wrote about that in the Elan build.

I did get a bit more done today.  Lucy and I did the first layer on another roof panel.  I bought some 5 oz plain weave fiberglass, and it's really nice to work with.  Wets out well and clears bubbles nicely.

I started prepping the hood for the hole fill.  I found an appropriate sized aluminum plate to use as a backer.  This got covered in packaging tape, and I marked the hole size and location:

The carpet tape then stuck the whole thing to the outside of the hood:

I'll pack the edges with tacky-tape to give a nice vacuum-tight seal.  Maybe overkill to vacuum bag it, but I'll know for sure it's good and strong.

Inside view:

That's all for now.

It looks like some of those cracks extend into the fiberglass.  I am not aware of any kind of paint / filler / resin that will provide enough strength to bond that damage back together.   If the cracks are into the fiberglass structure, you really need to verify that they do not extend completely through the fiberglass.

Were it mine, I would grind most of the gel coat off and bond a layer of chop strand mat with epoxy resin onto the body.  If the cracks extend through the body, you may need to do the same on the inside of the panel. This would provide a stable structure for your bodywork, physically bridging the cracks and bonding the body back together. 

From what I have seen, cracks in fiberglass are a result of flexing - at least in boats.  Can't believe that this is not the same.  Unreinforced panels need to have some kind of bracing to stop them from flexing (unless it is simply poor construction in the first place - I'm talking to you Bayliner...)

I have a  1973 2500M and in looking into the build of these shells, I have been told that a clear gel coat/resin was used over the fiberglass.  Makes me wonder if you are seeing cracks in the resin/clear gel coat vs cracks in the fiberglass.  How deep are your cracks?  Just curious. Thx

In reply to Bigbrowndog :

Welcome!

Yeah, it does seem to be clear gelcoat over the glass.  A lot of the smaller cracks seem to only be in the gelcoat - they should be easy to fix.  Some of the deeper cracks do indeed go way down.

I've been doing a little experimentation on this, though probably my final fix will look a lot more like what TurnerX19 was suggesting.

I mixed up some resin and filled it pretty heavily with chopped fiberglass filler:

(Note: Save your yogurt cups!)

This got smeared into a couple ground-out cracks - I really tried to pack in as much as possible:

A close-up:

Added a layer of peel ply and then tightly covered the area in packaging tape.  This does a reasonable job when vacuum bagging isn't in the cards.

And here's the same area cured and sanded smooth with an 80 grit DA.

Not bad, though seeing the zillion blue cracks makes me cringe.

Ultimately grinding away of some of the old gel and adding back some nice new FG cloth should make it much stronger and more stable.  Which reminds me that I want to weigh the hood as it is now, and track how much I'm adding or subtracting.

In reply to TVR Scott :

I think that some of the tiny blue lines are actually where surface tension is pulling your “dye” into voids between parallel fibers, where the original resin never penetrated.

In reply to Slow_M :

Maybe so.  The tiny cracks do seem pretty random.  I wouldn't mind just wicking in some thin super-glue to fill those super-tiny ones.

Looking at the hood a bit more, I think it took some damage to the passenger's side.  The big indication being the big chunk missing out of the bottom corner, but there were other signs in the chassis and suspension.  The bent steering rack being one!

I think maybe that impact radiated thru that side of the hood and created the large number and density of spider cracks.  I don't see those nearly as much on the driver's side.

Also, the thin area above the wheel wells looks to be just weak by design.  Both sides are the same and PO made an attempt at fixing that area.  I think a couple layers of carbon under those spots will be appropriate.

I always liked the Aston Sage green, looks really classy and can be seen on Retropower's project Utah on youtube

the gunmetal shades like Bond's aston look fantastic too

I am doing my client's TR4A in that same Aston Martin color,  it is an elegant and stunning color in person. 

Scott, you are scaring me away from ever getting a fiberglass car, I guess I never really looked closely enough to realized how fiberglass ages after 40 years. Metal cars rust, fiberglass cars get spider cracks, makes sense. Either way, you resolve it, just like you have done on the rest of the build and in the end it will be stunning. 

dherr (Forum Supporter) said:

Scott, you are scaring me away from ever getting a fiberglass car, I guess I never really looked closely enough to realized how fiberglass ages after 40 years.

All this pain is really making me think I'll just vinyl wrap my Europa. I can only imagine how awful it'll look if I check for cracks with the same attention to detail.

In reply to Brotus7 :

I suffer so you all don't have to.

More progress: time for a lay-up to fill in the jagged "carb hole" in the top of the hood.  Earlier on you can see how I beveled the edge back and prepped the back side for the lay-up.  Now to do the job.

<Sticky mess, no hands free for pics, blah blah blah>

And the lay-up is done:

Bagged and curing:

I need to have a look at my vacuum pump.  It's pulling pretty low.  Might need new vanes or seals.

Here's the area after cure.  I could have been a bit more thorough removing paint around the hole, but anything covered by epoxy will get ground off.

And here's the same flattened out with a DA sander:

I wasn't very careful to cut plies to match the hole and bevel, so hence a fair bit got ground right back off.  No concern - there's plenty of structure there.

I'll need to smooth down the top side once I have an extra set of hands for flipping.  My aluminum plate fell away just a little so the patch is a bit proud of the exterior surface.  It'll get the DA treatment too.

Here's the whole thing as it sits:

I need to get all the paint off, and I'm trying different methods.  Citrus stripper works really well, but it tends to leave the old resin soft and mushy.  I worry that's affecting the integrity, so I think I'll avoid it.

The hand scrapper on the left gets some of it off.

I tried a fiber-bristle cup on my drill and that works - eventually.

I had decent luck walnut shell blasting, but that's really messy and it's snowing outside right now.

Any thoughts?  Maybe I'll try a different flavor of paint-stripper and see if it doesn't soften the same way.

I had good luck with Ready Strip that is available at Home Depot.  It didn't affect steel, but not sure what it may do with old fiberglass.

The best glass man I know uses a razor blade and lots of time. No chemicals, and no sand paper until he is fixing cracks. Really tedious.