My 1973 TVR 2500M : Renew and Restomod

Chemistry time!

Taking apart the doors has brought back an old issue with this car: all the old bolts are rusted and suck and always break.  When I took apart the hinges I broke off several bolts in the aluminum hinges.  Also the hinge pins totally wallered out the steel base-brackets, so I need to get the hinge pins out, fix the brackets, and put in new pins.

I felt, deeply in my heart, that there should be some chemical method of selectively removing steel from an aluminum part.  A bit of searching, and I found out that there is!

The secret ingredient: Alum.  This stuff is actually Potassium Aluminum Sulfate.  I found a couple references to the process on an aircraft forum, and also found that watch-makers frequently use the technique for removing tiny steel screws from brass parts.  The Cliff's-notes:  mix with water, heat to off-boiling, add part and wait for the magic to happen.

It's used not only for dissolving steel out of non-ferrous materials, but for paper and fabric dying, and also in pickling!  You can actually get little food-grade tins of it at the grocery store in the canning section.  I bought a pound of it from Joann Fabrics for about $20 shipped.  They have 5 lb bags too.

In preparation, I also bought a cheap-ass electric hot-plate and a $6 aluminum pot from the local Goodwill store.

Mixing ratios are a little uncertain on the internet, but I went with 1 cup of Alum to 4 cups of water.  It seemed to fully dissolve as I heated up the water.

And the first hinge is happily bubbling away:

That's it for now!

Interesting! Curious to see the results!

How long are you guessing the process will take??

jfryjfry said:

How long are you guessing the process will take??

Not really sure.  It bubbled away all day yesterday.  The bolt holes now look really clean.  The pin looks pretty unaffected, but it's a pretty big chunk of steel.  I'm going to clean out the pot and get another batch going here shortly.

Would probably be better to drill a smaller hole thru the pin so that the liquid can have lots of surface area.  I think I'll give that a go before starting it boiling again.

Today is five years.

On previous anniversaries I've given some thought to the past year, discussed the progress I've made, and considered what I might have done differently and where things are going.

Introspection is overrated.

Let's make some noise.

Throw me a thumbs-up for another year in the can.

Niiiice!  One thrown thumb.  Don't ya love when a plan comes together.

Nice!

Ima have to hook up the surround sound to this post.

Woo hoo!

I wanted to bolt a seat down and take it for a spin.  Maybe get the steering hooked up first.  This thing is gonna rip.

Excellent job, Scott.

Nice! congratulations

In reply to Shavarsh :

Very exciting to see that man. Very well done. I need to get back on this project after my winter off! 

If there ever was a car in search of an engine, the TVR 2500 was it. Congrats! This may be the best conversion yet.

Nice!!!  I can't wait to make some noise of my own. 

Woooohoooo!!!

That grin at the end..  Well earned!!

Nice! 

Nice! I can hardly wait for this moment to happen in my garage!

Fantastic!

Thanks everyone for all the internet-high fives!

I was super happy how quick and easy it fired up.  Like the almost-new mostly-stock engine that it is!  I was worried the exhaust would be really loud, and it wasn't at all.  The dual Cherry-Bombs are getting the job done for now.

It was a really fun day.  Joe TR6, GXP Kirk, and Voz Proto all made it for part or all of the day.  Joe let me drive his Mazdaspeed Miata, and I'm totally in love with it!  Add in some good pizza, and it was all the fun.

We did run into a one big issue, and that was the fuel filter/regulator.  This is the C5 Corvette unit that Tanks Inc sells with their kits.  It has male quick-connect fittings for the inlet/return fittings, and a female fitting on the outlet side.

Well, the outlet would not seal without being pressed tightly into the filter.  Like spill gas everywhere mess.  We tried having Joe just hold it, which sort of worked.  Ultimately I busted out the safety wire:

This worked. (?)

A bit of internet searching showed us that we weren't the first people to have this problem.  I'm guessing on the actual Corvette that the outlet is a very well supported hard-line, and the filter is also very rigidly mounted.

To fix the problem I bought this one - also from Tanks Inc.  Good that they have a much better option.  Eliminating the quick-connect fittings feels like the right way to go here.

Otherwise, it's back to body stuff.  I got both doors fully disassembled, and there will be work there for sure.  Here's what the door handle mount looks like:

That'll be a patch and reinforce job.  Rivet-nuts too, I think.

Also, reporting back on the Alum experiment.  It didn't really work at all.  Worth a try, but not every experiment plays out.

That video made my day! Great when you see all your efforts are getting closer to the goal. That car is going to be quite a ride as those ecoboost engines are really powerful. Congrats!

You know it's a proper British car when you get it running using bailing wire.

That fuel filter should do the trick.  I like the idea of eliminating the quick disconnects.

Just replying to confirm, the weird plastic fasteners and wood spacers were exactly what came out of my doors as well. My spacers were similarly disintegrated. Plywood seems like a poor choice for a component where water is draining through it by design.

Glad your motor is up and running as well!

In reply to ViperT4 :

Good to know all the wood isn't just on mine.  Poor choice of materials indeed.

Maybe when I start making spacers I'll ask all you other TVR guys if you want a set.  Would be easy to mill out a bunch once the machine is on and cutting.