240Z Resto - 01/1970 Car

[Careless]

anyone know the OE finish on the regular lug nuts? this kind here:

 

 

They were some sort of black-ish phosphate coating. not sure if I should re-coat to that finish or if they're supposed to be something else.

[Patcon]

I saw a similar green media on Summit Racings website. It was reasonably priced if I remember. I thought I would use your directions and try polishing some of my pre-plate items. So far I haven't had much success yet.

[Careless]

I saw a similar green media on Summit Racings website. It was reasonably priced if I remember. I thought I would use your directions and try polishing some of my pre-plate items. So far I haven't had much success yet.

 

CARELESS MEDIA TUMBLING GUIDE

(skip this post if you're not interested in reading my process!)

 

You can tumble copper, steel, iron, brass, aluminum, magnesium, and even opaque or clear plastics.

 

The tumbling process does a great job of bringing fogged plastic back to life too. It does a good job of cleaning aluminum to a "clear anodized" look, and it does a great job of bringing brass to an almost "as manufactured" look.

 

parts that should not get media inside, like oil pressure senders or short brake lines should be capped off, unless they can be blown out with brake clean and air pressure- or with a suitable solvent.

 

- 11lbs of media

- start with 5 - 6 lbs of m6 to m12 nuts, bolts, washers.

- green pyramid media

- 3 cups of water

- 3 or 4 squirts of dish detergent

or

- 1tsp of Potassium Hydroxide flakes (speed clean active ingredient, can be bought at soap making supply or online. very inexpensive)

 

occassionally you will get a large soapy/sudsy foam filling the entire bowl. That can be whisked off the top and put into a bucket. To combat this, I might try the new Tide HE Turbo laundry detergent as an additive. It has a high cleaning power but low suds. 

If you use just the Potash flakes, it is a very slick solution with very little soapiness to it. It will also coat the parts for upto 10 days to prevent flash rusting. I prefer having some sort of mild grease cutting fluid in there, like dish detergent. It keeps the media somewhat clean as well.

 

I keep a large bath towel handy to keep wiping my hands. I found a lint-type (not lint-free) towel is best for cleaning hands periodically and also wiping the parts down. The wet media water dries on the towel quickly, and you can just bat the towel outside to get it to dust off if it gets a little crusty.

 

painted items or small items with crevices or places for the media to get stuck will not have action in those zones.

recessed drive screws will not have the screw drive cleaned extremely well, and might have paint left over (phillips, slot, allen, torx, etc.) You will have to pick at these items with a small pick-tool to get the media out after tumbling, or grease out before tumbling. Sometimes the media water-slurry that is generated from tumbling will get in there and clean it out for you, but it also needs to be picked out as well. Twisting the screw head into a stiff bristle brush can do quick work of this if you don't let the media harden up (i.e- clean while still soapy/wet).

 

Any items that have small casting imperfections, small pits with rust, or small tool-path marks or machine grooves (like the alternator pulley from the grapefruit style early series 1 alternators), will need to be either wire wheeled or sprayed with some sort of paint/rust remover like Eazy-Off Oven cleaner, and brushed and washed briefly before being tossed into the tumbler bowl.

 

The good thing about buying an extra bowl is that you get a second tightening knob for the lid. With this second knob, you can screw it down on the all-thread and have one knob/washer/rubber washer combo that threads all the way into the tumbler and holds the bowl down. Then you can put the lid on and thread the second knob as you would normally. This prevents the bowl from warping due to parts being off balance or the solution going cement-like over the course of a couple of hours. This warped one of my bowls and now I have to get creative on how to fasten it down. It widened the all-thread hold on the bowl to where it moves around too much, so i put a plastic bushing there to take up the slack. I found that holding down the bowl with the knob inside before the lid goes on gets maximum centrifugal action on the small parts that float around the perimeter of the inside of the bowl, and knocks them into the center. 

 

To fish items out, I first experimented with a magnetic wand with an LED at the end, but the magnet was not strong. A regular magnetic wand with no LED works a lot better... But then I found an old magnetic bolt tray that the magnet separated from, and it worked amazing. An old mechanical platter hard drive magnet would be even better. For the extra small items like the 2-wire clamp washers and screw plates, I just ran the tumbler with the magnet in there for 2 or 3 minutes and took it all out, covered in metal-water and small parts. Did that a couple of times. The trick here is to have two buckets. One with soapy water that you immediately dunk the items into and swish them around to get any metal dust off them (do this without the magnet attached to them).

 

Then another clean water bucket to dump them in, temporarily while you do the rest.

 

At the end, I use a 1lb dollar store scooper and drop 1lbs of media into a stainless strainer and run water over it to clean it. When I go to dump it into a small clear container, I keep a magnet at the end of the scooper to catch and left-over items. In total, I may have left about 20 items in the bowl throughout the multiple (maybe 15-20) washes. That's not a bad percentage for my method, consider the vast amount of items, especially miniscule ones.

 

Once the media is clean and the parts are all collected, I take them out of the clean water bucket, and put them in the strainer. Wash them really quick (they're wet already, anyways), and then wipe them with a thick towel by dropping a handful on there, and folding it over and rubbing briefly.

 

I then put them in the strainer and spray WD40 on them, and put them in a clear bin for sorting later.

 

I later learned that some of the plastic media residue from my experimenting with various compounds like paint polishing paste, simple green, powdered/bleach type dish cleaner CAN leave a fine plastic residue on the threads of certain items. I used a stiff brush and held each and every bolt or item in my hand and just rubbed them across the brush 5 - 10 times. Each item takes about 2 seconds to do. For nuts, I did not bother to wire brush the inside, as I did not have a small bristle brass pipe cleaner to fit in most of them.

 

The only issue is that under the plastic is some moisture, so it will flash rust under the threads or not get plated. But I use Marine Grade Synthetic anti-seize on virtually everything I put together, so it's not a big issue. It works better than plating does to begin with, IMHO.

 

As far as time goes, on a per-batch basis... 

 

- setup (5-10 minutes)

- magnetic fishing (10-15 minutes)

- cleaning media (30-40 minutes)

- cleaning items (30-40 minutes)

- WD40 spray wipe and spray (5 minutes)

 

Keep in mind that you don't need to wash the media or fish out every item every time. You'll know when the media gets grimy. Some people have said to keep running it, it doesn't matter. But there were times when I needed to know that the only things in there were alternator parts, or an assembly of something or other, so I was forced to clean out the media.

 

If you're not cleaning the media you can just take out what you can with a magnet, and put the next batch in. You don't need to take everything out. I found that the green plastic media is very forgiving in that it BARELY takes off much metal. It's so fine that it turns into a dust at the bottom of the bowl. It would probably not register on most vernier calipers- it's so fine.

 

The largest item I've put in the bowl is the entire e-brake linkage assembly, except for the long rod that fastens to the cables. The entire pivoting lever assembly that is two welded washers to a tube with a long arm with the clevis pin at the end fit in there, and with the exception of a couple of areas not being scrubbed because they get no media passing across- it came out reasonably well. I'm going to bead blast those areas and run it back in the tumbler for 2 hours and it should be ready to go.

 

With all that said, it usually takes about 2.5 to 3 hours when doing a full media swap. I bought the extra media so I can cross-mix from separate batches to prolong the use of the media. But I will not be doing that from now on. I will keep the media separate so that I have some finer medias and some 'slightly used' medias. They still work just as good as they get smaller, sometimes even better. So I will use that for getting into smaller parts.

 

I might experiment with a ferrous media that is not as aggressive as metal shot at some point. I would like to try something smaller with sharper edges that retain their edge for a longer time to get into smaller threads, but so far plastic media is good!

 

I know it's not exactly healthy, but I quite enjoy the "not burnt, but kinda warm" plastic media smell too  wheeeeeeee!

 

For last batch of stuff, I tried to etch the little pieces of rust off by leaving them overnight in Apple Cider Vinegar, brushing them briefly, and then putting them in water + baking soda to neutralize the rusting action before dousing them with WD40 as well to prevent rusting.

 

I would say it made the items appear a good bit lighter, and did in fact take some rust from small machine marks and threads that were too far gone to some degree... However, I'm sure if I left the items in the vinegar for say... 3 or 4 days, the results would have been way better. It does have a slight "etch" to them, and they are slightly lighter than before they were tumbled.

Edited June 3, 2015 by Careless

[Patcon]

Thanks Careless

[Careless]

Maybe I should move that post to a new topic?

[zed2]

26th-Z sent me some empirical evidence of the 2-wire clamps being bright silver zinc on an early 70's car, with low mileage at least in the engine bay. 

Please share the information 26th-Z shared with you.

Thanks,

Keith

[Careless]

Please share the information 26th-Z shared with you.

Thanks,

Keith

He has posted the images before in another engine restoration thread. Hopefully he'll see this thread and pop them in here. They're not my own personal photos so I'll wait for him to give the green light or post them.

 

But there are a number of photos with pretty clear shots of some tarnished "clear zinc" coated clamps next to some tarnished "light yellow zinc" coated throttle linkage parts. So the difference is quite visible, I'd say.

[26th-Z]

These are two of the clearest pictures I have.  Although this is not the earliest of cars, the brightwork is very nice and clear in color.  One thing we noticed was the clamp for the coil.  It is silver zinc on my cars.

Edited June 8, 2015 by 26th-Z

[Careless]

These are two of the clearest pictures I have.  Although this is not the earliest of cars, the brightwork is very nice and clear in color.  One thing we noticed was the clamp for the coil.  It is silver zinc on my cars.

 

For that reason, I dropped the coil bracket off today, and asked for it to be clear/bright zinc, instead of what's pictured there. Some things can slip up, but the clamps were clear/bright zinc on the other photo you posted in someone elses engine resto thread as well, so for the clamps I did not go yellow zinc, nor will the coil bracket be on this particular resto. I looked under the unpainted portion and it was definitely silver- no hint of yellow of any kind.

[Careless]

Picked up the valve cover, alternator housings, lower water/thermo housing, and the timing cover today. Looks great! I think with a little cotton cloth rubbing and some sharkhide, it's going to be amazing!

 

will post pics soon. 

 

Edited June 8, 2015 by Careless

[Careless]

Acid dipped items arrived back today.

 

A little rustier than I expected under the intake paint. I'll have to attempt to sand down the bumps and whatnot on the exterior where the intake was scratched and then blend them gently with a wire wheel before sending them for powder coat.

 

will post pics this weekend. Just gettin' a little busy here with all these parts everywhere!

[Careless]

Vapor Blasted Alternator Housings: