1969 Drive Shaft Restoration

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Update 03-15-2024

Drive shaft has been removed from the car. Notes - U-joints are SPICER brand and have black dust shields. There are grease zerk fittings on each end. Was very careful taking the u-joints out so that I could put them back in again since I had trouble finding SPICER joints with black dust shields when I restored the half shafts. Did note that 3 of the 4 caps have 32 needle bearings inside the cap and 1 cap on each end had 31 needles. I don't know if that is supposed to be that way or one got missed from the factory or lost during installation. Caps moved perfectly free, no binding, smooth rolling, with plenty of grease in them. Car is 56,000 miles on it.

Drive shaft rear facing flange shows a green paint mark. There are the presence of two circumference marks where I believe the paint marks used to be. I have documented those locations and marked them with white grease marker so that I can add the paint marks back later in the same locations.

I made a bathtub out of plastic gutter with end caps, lined the tub with doubled over 4 mil plastic, filled the bath with Evapo-Rust and began the soak overnight.

I did put cold bluing on the half shaft weld areas for both the LH and RH half shafts. They looked great right after it was done. 24-hours later they seem to have faded. May have to redo those again or go a different route to get the bluing needed for the welds.

Will post more as restoration continues on the drive shaft.

Kevin

[Patrick H.]

Re: 1969 Drive Shaft Restoration

If you had already clear coated the half shafts, the bluing won't work. It has to go on raw metal.

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Hi Patrick,
Half shfts were coated with matt clear about a year ago when they were restored. Tried just going right to bluing and it did not take at all. It was obvious the coating prevented the bluing from reaching the metal because nothing transferred at all.

So, I went to this next step.

I used acetone to clean the weld area first. Then, I used my Dremel with a carbon steel brush attachment on the Dremel to clean all of the welds on the half shafts. Then, applied 2-coats of cold bluing to the welds with Q-tips. I poured the bluing from the bottle into disposable plastic cups so that I would not contaminate the original bottle of bluing solution. It looked great right after it was done on 03-14-24 and 24-hours later it is hard to tell that it was even blued.

[Patrick H.]

Re: 1969 Drive Shaft Restoration

I use Q-tips to paint it on, one layer at a time, every 3-5 minutes, until I get the look I want.
It only has to dry before you put on the next layer, and that takes the 3-5 min or less.

Some bluing is darker than other, and some takes more applications.
Alternately, you just keep wiping it on with the Q-tip until you like the color.

It takes some experimentation. I find that each metal alloy is different, and it's why I have 4 different brands of it here.

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Some items noted following the 24-soak in Evapo-Rust

- there is a yellow directional arrow indicating which end is the front of the drive shaft, looks like yellow paint
- the two circumference paint lines are 7 3/8" and 9 1/4" from the edge of the rear flange. New paint will go back in the same locations.
- after initial hand sanding with 220 grit, I can see the 1/2" wide extrusion marks running lengthwise. That will get blued eventually
- PN located on the end of the forward flange PN 3952197 and below that what looks like a Chevy bowtie symbol and PN 510

I have purchased another bluing solution to try and darken the weld marks on the half shafts. Will do that 03-19-24

Media blasted the flanges, the welds, and the spot welded drive shaft balance weights.

More updates to come as time allows....

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Update 03-17-2024

I wanted to stop at this point to allow some time for opinions and evaluation of work completed so far. I have not added the bluing stripes or the paint stripes yet to the drive shaft. Those will come if this seems good enough to proceed to the next steps. I realize it is the weekend so I'll pause for 3-4 days to allow time for opinions.

Thank you in advance for your comments. I have skin like a rhino so don't worry about hurting feelings. I need honest opinions. I can continue to hand sand the shaft but I'm honestly not sure that it should be perfectly smooth. It's important to me that I get it right.

The directional arrow is in there deep. Fortunately, it is right on the edge of the longitudinal 1/2" wide longitudinal bluing strip so most of it will get covered. I don't think it is OEM but I don't know for sure. I'm a novice, first restoration project. Would love to hear from an expert on the presence to this directional arrow. I'm guessing the drive shaft came off this car at some point and someone used a yellow grease pencil to mark the orientaion to reinstall it correctly. Yellow came off but the impression is still there - looks like a stain mark now.

Kevin

[Gary B.]

[Patrick H.]

Re: 1969 Drive Shaft Restoration

Looking at the shaft, cleaning those pits is a challenge.

If you have a sacrificial shaft for testing, I would think that low pressure baking soda blasting or vapor blasting might clean them, or possibly walnut shell blasting. Sanding or steel wool won't do it; I've tried.
I think whatever cleans the pits will also remove the arrow remnants.

[Kevin S.]

Re: 1969 Drive Shaft Restoration

I'll give soda blasting a shot to see if I can clean up the pitted areas more, also have some used glass beads if I need to go a little more aggressive. Thank you.

P.s. - never tried walnut shells in my Harbour Frieght hand-held gravity feed blaster. May have to experiment with that too.

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Hi Gary,
Thanks for the feedback. I just did not know. I suspect the drive shaft was removed before and the mechanic(s) just used a yellow grease marker to make sure they put it back on the right direction.

I'll keep working on the arrow to see if I can get more of it off. I'll do some more sandblasting with soda first and maybe used glass beads to see if I can get the pit areas cleaned up better and I'll work on the arrow at the same time and see if I can get it off.

Kevin

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Update 03/27/2024

- Had a friend make a wooden cradle to hold the drive shaft, easier for hand sanding, bluing, and painting
- Went back over the drive shaft with 70 grit aluminum oxide media blasting, hand sanded with 400 grit, I'm happy with the finish
- Bought Birchwood Super Blue per Patrick to try another bluing material that might work better...and it does
- Taped the 1/2" strip to cold blue the extruded seam following the previous seam marks, did 4 light coats, 30 min between coats
- Added the green alignment mark on the rear of the drive shaft following the location of the previous original green mark
- Measured 7 1/4" from the rear flange and added the orange stripe to the drive shaft in the same location as the previous mark
- Letting the paint marks dry overnight before doing the green circumference mark and adding the Quanta Products stencil

Hope you like the progress. Stronger cold bluing solution made the weld marks darker and look more original

Shout out to Carolina's Chapter NCRS members. I enjoyed the Chapter event March 22-23 at Kevin Whitaker Chevrolet and learned a lot.

Kevin

[Gary B.]

Re: 1969 Drive Shaft Restoration

Kevin,

This is a system that Joe Randolph built to facilitate painting the circumferential stripes on a driveshaft. I have a movie showing it working, but the DB doesn’t allow me to attach that movie file, so here are two sill images.

IMG_5229.jpg

IMG_5230.jpg

I used it to do the stripes on my ‘66 driveshaft and if I do say so myself, the stripes came out looking great. The stripes edges were not taped off when the driveshaft manufacturer added the stripes, so using Joe’s system produces a factory-like result, that doesn’t have perfect stripe edges. Joe didn’t want the system back after I was done with it and it’s been sitting on a shelf in my garage, taking up space for too many years. I’d be happy to send the system to you. You just need to provide a variable speed drill motor that can be set to run at very slow speed. In my hands, I wound up with a bit of a jerky rotational motion. When Joe used it he got a smoother motion. But Joe was more careful in setting up to use the system that I was.

I would really love to give the system away to anyone who wants it. It’s such a sweet design and I can’t bear throwing it away.

Gary

[Kevin S.]

Re: 1969 Drive Shaft Restoration

Hello Gary,

That is a really sweet DIY setup. I wished we had crossed paths sooner. I also used a variable speed drill also but with a cable tie looped through the u-joint flange so that I had a nice, slow, constant speed. I just clamped the drill chuck to the cable tie. Not nearly as impressive as Joe Randolph's device but it worked for me.

I will be putting the green stripe on later today. I'll take a still shot of my "not-so-fancy" set up. I can say that the wooden cradle my friend made for me is pretty cool and it works great. The 4 x 4 block I'm using is steady, high enough to clear the flanges spinning, and wide enough to be nice and stable. The only minor challenge I had putting on the orange stripe was keeping the longitudinal motion steady left-to-right thus the reason for why I added the painters tape mark. It gave me a fixed location to gauge where I needed to apply my stripe(s). I did not paint up against the painters tape. I only used it for my bearings so that my stripe(s) would be straight. A bit hard to see in the pictures but my orange stripe is about 1/16" away from the painters tape.

Kevin

[Gary B.]

[Kevin S.]

Re: 1969 Drive Shaft Restoration

All done with the drive shaft. Here is the BEFORE and the AFTER pictures....

I did put a light coat of matt clear on the drive shaft just to prevent it from rusting again in the future.

Kevin