My '76 restoration (long post)

[denpo]

Say Denis - glad those B-Pillar mounts fit so well!
Cheers - Jim

Jim, would you refer to the B pillar weatherstrip one you sold me (or gave, can't remember)?
They were late C3 and I ended up ordering from Dr Rebuild the correct year ones.
I'm keeping them in case GM revised the design for a reason (like leaking...)

 

[phantomjock]

Hope you'll find a good use for them - they were just on my shelf for so many years... Happy New Year!

 

[MYBAD79]

No updates? Driving it ???

 

[denpo]

No updates? Driving it ???

No, not much done those days.
Some people at job decided it was time for me to eat some double stuffing shit pie. I'm still dealing with that, and it bothers me enough I'm not in the mood to do thing right in the garage.
For now I'm trying to make lemonade while making sure everyone get some splash from the pie.
Thanks for asking Karsten. :drink:

 

[SRountree]

Man I hear you... I am starting new job Feburary 1st because of people! I hope it gets better for ya... Quickly!!!

 

[Fastphil]

Any progress?

 

[denpo]

Hi Phil, hi everyone.
I apologize for leaving you all hanging for so long.

I have the habit of posting something when it's completed , I've been posting several half done side projects in the past that went nowhere and I that kind of suck.

I'm been stuck in some doldrums for quiet a while, and there is many reasons to those thing not getting completed :
-Setbacks, knowing I have to get through my fuel piping and my transmission again was a bit discouraging, made me lost some momentum.
-A couple of they are mainly due to the fact that many stuffs I ordered from China never showed up. Waited almost 2 months for parts. I just got refund and proceeded to order those China parts from USA, even if US dollar is not cheap these days.
-A limit to my sub task system : running many sub tasks in parallel made that I could always make progress somewhere. Now that tasks are final (and stalling), the progress is much less visible.
-Mrs Denpo waited long enough, some promised home renovation had to happed.
-Lazyness : Even if winter was mild to Montreal's standard it took its toll. Driveway's last snow patch is melting away, I start to get the urge to take the Vette for a ride again.

That being said, since you're asking, let me wrap up an update of those half baked things.

Windows: I had two sets of door windows, the original ones and a set bought later on. Both sets were scratched. I bought a Porter cable orbital polisher and some cerium oxyde and tried to polish out the scratches. Worked with the dull area but not much with the scratches. After the polish work, I had the original set, that had mild scratches and a couple of rock chips, the bought-after set, without chips but with more and deeper scratches, and the option to buy a new set (boy, those ain't cheap). After much thinking, I decided to go with the original ones, if I have money to spend on the vette, buying new glass is not top priority.
But that mean you have to admit you've wasted time and money for nothing and more importantly that you're settling for a non optimal result. I knew I would get bitten by the painted car syndome and start obsessing about perfection. I think I've overcome this now.

Differential: I happened to have the chance to buy a 3.70 differential, 3.55 would be perfect, but at least it would have been better that the 3.08 I have installed. I made the mistake to take time to sandblast it before opening it, I was trusting the seller too much. I then opened it to a cracked posi case. damn it. I'm not worrying money wise, seller is a good guy we'll fix this, but again it's lost time.

Doors: turn out the door actuator wouldn't cut it, even with the lever arm I added. So I ordered heavy duty set, those with the motor parallel to the actuating shaft, not perpendicular. Well, one of those lost package.

Taillight: they're in, with their backing plate, junction box and everything, but still missing the dedicated brake signal line installed thru the firewall. I could have this done, but I want to mess with the harness one last time, and that will be for installing the door actuator.

Emblem: ok, I have some pics for you :

That's the nose emblem.

I had it 3D printed, with a laser-resin process, which is much finer than the hot plastic one.

I made it with the nose 12° angle for a tight fit.

Then I'm going to cast it (along with the flat emblem I made long time ago) in aluminum.

The furnace is in the making :

It's cast in refractory cement, not cheap (150$ in cement alone), but supposed to withstand 3000°F. Youtube's Paris plaster and playsand furnace don't last 10 cycles, this one should fare better.

I've trapped a piece of refratory foam where I'm suppose to drill the burner hole, because this cement a really tough.



Here's my casting flask, which is complete, with the alignement pins.

I decided to go the propane way for heating up my metal.
The pieces for the burner are at my buddy's shop, it need precise drilling and welding I can't do my self. I'll talk about it when it's done.
I have the silted play sand and the bentonite to make casting sand, a box of borax for the flux, and a set of stainless steel kitchenware.
I could probably have been casting as we speak, but the crucible is part of the "never arrived" parts.

Wheels :
I've polished the wheels :

I'm gonna paint the unpolished area flat black. I initially wanted to wait until painted to install the new cooper cobra tires, but miscommunication happened and my buddy guy took them to the tire shop too soon.
He is also currently making custom adapter that will serve as spinner support as well as hub centering ring.

Windshield:
I have collected the urethane and the prep products needed to install it, but I'm still a bit puzzled about the spacer thing. A forum member had a magnificent webpage dedicated to that, alas it's down now.
I'd like to find an image of those spacer, and where it's supposed to go.

That's it for now.

 

[BBShark]

Wouldn't it be easier to CNC that emblem (as opposed to casting)? Or even DMLS.

 

[denpo]

Wouldn't it be easier to CNC that emblem (as opposed to casting)? Or even DMLS.

Easier probably, but everywhere I checked people were asking for my left kidney.

 

[BBShark]

How much is a left kidney?

 

[denpo]

I admit that with a 5D CNC the piece would be easy to make, but maybe one in maybe 5 company I contacted answered back.
Prices were $500 to $3k.
500 was for DMLS, and it would still require plating.
Right now I'm around 500 for the whole casting setup (3d print included), and it's much more than a simple piece of metal, it's a new horizon for making stuffs.
Casting metal have always been part of the stuff I want to try in my life. That's why I'm investing a bit for something reusable in the future.
We'll see if the result is workable *finger crossed*
My plan is to polish it and have it chrome plated.
If things goes well, I have a set of custom side script in the making, the design is done, I'll post an image soon.
There is also this heavy steel bracket we made that hold my alternator, an aluminum replacement would be a good candidate for lost foam casting.

 

[phantomjock]

New skills, new tools, new hobbies. Good on 'Ya! Maybe find yourself in a casting business for other members - eh?

Cheers - Jim

 

[BBShark]

I admit that with a 5D CNC the piece would be easy to make, but maybe one in maybe 5 company I contacted answered back.
Prices were $500 to $3k.
500 was for DMLS, and it would still require plating.
Right now I'm around 500 for the whole casting setup (3d print included), and it's much more than a simple piece of metal, it's a new horizon for making stuffs.
Casting metal have always been part of the stuff I want to try in my life. That's why I'm investing a bit for something reusable in the future.
We'll see if the result is workable *finger crossed*
My plan is to polish it and have it chrome plated.
If things goes well, I have a set of custom side script in the making, the design is done, I'll post an image soon.
There is also this heavy steel bracket we made that hold my alternator, an aluminum replacement would be a good candidate for lost foam casting.

That a $200 CNC job max.

I would like to see your lost foam process. Post some pictures.

 

[denpo]

New skills, new tools, new hobbies. Good on 'Ya! Maybe find yourself in a casting business for other members - eh?

Cheers - Jim

We'll see. I've watched many video on youtube, but it's nothing compared to the real deaL I even bought a pyrometer to make sure metal is at the right temperature, at least I know I've done all I could to make it right.
Can't wait to break my first casting.

That a $200 CNC job max.

That's interresting information you bring there, I'm gonna make another search for CNC companies, thanks.

I would like to see your lost foam process. Post some pictures.

Dully noted, I will.

 

[denpo]

I moved forward with the furnace.
It's only missing the gas regulator (0-20 psi), it's waiting at the border, with many other parts.

It's based on Reil's Burner Design and use mostly plumbing hardware.

My buddy Guy stepped up the design with welded support ring to hold the locking screw.

Here you can see the #60 hole from where the propane will come out.

Still need to build some kind of tripod to keep it in place.

Covered the inside of the furnace with sodium silicated based refractory grout to fill all the little air hole in the concrete casting.

Here's how the burner is supposed to shop tangentially to the crucible, to form a vortex around it.

This week I've decided to get to the bottom of that differential affair. The seller proposed me a third differential, which finally have a uncracked posi case. I'm about to make a differential out of three blown ones. From the first I'm taking the housing, so we don't lose the sandblasting job and the time spend machining out the front bracket bolt.

Inner seems undamaged. I have to pickup a 1" 1/8 a Guy's shop to remove the gear.

Looks like it's always the same bolt that freezes in.

With the first housing boys we spent some time trying to push it out. No way, this how it ended after Guy machinied it out.

Here is the diff part graveyard, scrap metal man gonna be happy. I will keep a bad yoke to make a posi turning tool.

So, the three differential had grenaded themselves.
Two of them had their yokes grinding into the posi pin, and mushroomed at the tip, but one had what seem a nice pair that popped out of the differential like butter.
I've sent those images to Gary Ramadei, let see if he think I'm ok reusing those.

This is the only posi that didn't crack, even if it lost 2 ring gear bolt head.

Surely interferences happened lol, again I hope Gary approves it.

I plan to follow Gary's paper and make some upgrade, like ARP RG bolts, a polished posi case, solid left bearing cap and solid steed clutches. Just like Gary recommends.

And to wrap this update, a brilliant example of why I should wait before posting.
If you remember my previous post, I showed my new tires installed onto my polished wheels.
Well, I scored in the classified a set of 4 turbine wheel for 100$, couldn't pass. They are 8.5" and have the very same design than my rear 10.5" (yet, until today my front and rear wheel had different turbine design). I'm gonna take the two nicest of this bought set and use them as front rims in place of the current 7.5".
They are half an inch larger on both side and should fits without problems. We will install the tire on and test fit them.

 

[MYBAD79]

Hey, since casting metal is your new hobby, have a look at this:

http://youtu.be/8Xvsxarw-J0

Hope the link works.... Do you have fireants up there in the cold section of the continent? Lol

 

[denpo]

Hey, since casting metal is your new hobby, have a look at this:

http://youtu.be/8Xvsxarw-J0

Hope the link works.... Do you have fireants up there in the cold section of the continent? Lol

Oh yeah I've watched many of there, it's fascinating.
Fortunately fireants are nowhere to be found here.

 

[denpo]

It's been a pretty productive weekend.
First I decided to switch housing, as Gary spotted the one I took pic of had pretty deep grind mark on the RG bolt side. So we switch the one that still had the frozen bolt. This one is intact.

Let me show you the third housing, the one that didn't crack its posi case, and this is because bolts smacked right into the housing instead.
You see the bulge?

I took the posi case to Guy's shop, and first check for runout. 0.002" a the ring gear surface, we're good. (Pic is before actual measuring)

Guy machined all he could to clean the posi flange, and I used a several kind of grinder. Still rough, but it's coming along.

And, miracle, heavy duty door actuators finally showed up, and now it's doing the job with plenty of torque.

 

[GTR1999]

Hi Denis
Figured I would check in to see how you made out. When the posi was in the lathe did Guy check the bearing journal and dial it in as close to -0- as possible? I like to get those in to about 0005-001 max but a lot depends on the lathe and chuck used. Once the case is running true check the Case OD where the RG mounts and the RG flange on the case. You want those under 002" total. The RG has to be press fit on the case too, if it drops on you should replace the case BUT Loctite #638 is supposed to take up the gap and they claim it will work- I would use a new case if you find it loose. The flange OD doesn't mean much.

You will know if it's no good once you go to check the lash. The lash should be within 002 thru 360*. I have found some out 005 but not too many. Then I set them up like I outlined above and face the flange to -0- run out. Chances are that case is just chewed up on the flange web side and as long as there are no cracks and the run out checks are good you should ok, but blend and polish it better then I see!

 

[denpo]

Hi Denis
Figured I would check in to see how you made out. When the posi was in the lathe did Guy check the bearing journal and dial it in as close to -0- as possible? I like to get those in to about 0005-001 max but a lot depends on the lathe and chuck used. Once the case is running true check the Case OD where the RG mounts and the RG flange on the case. You want those under 002" total.

That's exactly what he did, we had a tad over 0.002" with the journal at within 001".

The RG has to be press fit on the case too, if it drops on you should replace the case BUT Loctite #638 is supposed to take up the gap and they claim it will work- I would use a new case if you find it loose. The flange OD doesn't mean much.

RG required some gentle hitting with a mallet to get off, so it seems still tight there.

You will know if it's no good once you go to check the lash. The lash should be within 002 thru 360*. I have found some out 005 but not too many. Then I set them up like I outlined above and face the flange to -0- run out. Chances are that case is just chewed up on the flange web side and as long as there are no cracks and the run out checks are good you should ok, but blend and polish it better then I see!

Polishing is on it's way, I'll post more pic later I definitely went further than what you see in the pics.