Another Z to see the roads again...

[ETI4K]

Yep, battery missiles are no good. 😉

I also plan to make changes to how the battery is secured.  I've been designing a tool-less latching mechanism, but haven't finalized it.  At the very least I will weld in a stiff nut plate (with 2 nuts) behind the firewall at the top of the battery.

Today, I made and burned in two weld nuts to secure the A/C and heater hose grommet cover plates.  I hate idea of using sheetmetal screws - so easy to strip.  Not at all sure how to work that solution for the cowl(?) between hood and windshield.

[ETI4K]

Finished the battery shelf remake. My personal M.O. is to always attempt to achieve perfection, and then live with the results, which are never perfect.  Each task is really just practice for the next one. 

 

In any case, I can live with it since it'll be covered by a couple of parts.  All new sheet metal.  The OEM shelf is 18 ga., while the metal I used is 16. Decided to run with the .062 to give me extra metal to sand down for final blending, but forming those 1/4" flanges around the curved cutouts was very, very hard.  Reused the vertical support underneath, and decided it too would be bolted in place aot being welded to the shelf.  I just had to add some meat to the bottom flange to get it to meet the inner fender well properly.

Currently waiting for confirmation of shelf location before drilling bolt holes everywhere.

 

[Patcon]

Ok so I would like a little tutorial on how you fabricated that battery tray! I can do some metal work but that is way beyond me!

[madkaw]

Always impressed with the guys on this site. Your work is spot on! 
 

[dutchzcarguy]

Nice battery tray!  Btw.. i remember that i took it also out of my 240z and later on i screwed it into place.. not original i know but it's handy.. especially when i restore the car for the third time in about 2-3 years i guess... (hope..) (will be my second restore of this car)

[ETI4K]

Thank you for the comments.  I really appreciate it.   

That thing took about every bit of a day and a half to make.  Started with the flat area and marked the opening cutouts.  Then I used a scribing tool to mark the length of the turndown flanges.  I just set the gap to about .210 and ran it around the inside of the openings to get the cut lines.  Used a jigsaw and die grinder to cut make the cutouts to the offset lines. 

I used a lot of things in the shop that were never meant to be beat upon as a backup rest for the metal while I slowly tapped the flanges down.  The big problem is that flat section needs to be held hard and flat while you are working the flanges down.  Because the flanges are so short, the metal is really hard to work (no leverage + work-hardening), and the flat area around where you are working it wants to deform upwards in reaction to the flange being deformed down by the hammer.  I did the best I could to use clamps or heavy pieces of steel to try to keep things in place, but it wasn't good.  

So I started using a little heat right on the flanges because they had to stretch as they make the curves.  That helped a lot, but not really enough, because the flanges didn't really want to stretch enough.  I was reluctant to add too much heat as I didn't want the flat area to easily deform - I wanted them to stay hard and flat.  At some point I used steel tubes and rounds of the correct diameters as forming tools where I pounded the rounds into the openings to force the flanges to stretch enough and make the profiles look halfway correct.  That also helped a lot, but if you look at the radiused openings they don't quite look right still because the flat sections started to deform under the stress of the round "forming tools".  So then I had to go back and reflatten the flat areas.

The biggest problem with forming the short flanges is that after you've formed the first one, it is now in the way of getting all the others done.  You have to have a piece of steel you can hammer against, it has to be large enough for the area you are working, it has to be small enough to fit between the previously formed flanges and you have to have a way to clamp it to something solid.  I have an anvil, dollies, lots of scrap steel, a million clamps, many hammers, and yet I still had trouble getting it all to work together. 

We were having having beers with friends yesterday at a great outdoor place overlooking a portion of the Shenandoah Valley.  My buddy used to make the bodies for his race cars, so I kept quiet and let tell me how to do it.  "Ahh, it's easy - you just need a positive and negative form."  Really?  Why didn't I think of that?  Of course I need forms 😁.  So there's the challenge.  Make forming tools.  Those curves are organic.  It's totally doable to make in wood using a handheld router, but it would some slow and very careful work.  But at .062, CRS is going to win against wood (unless it's perhaps Ipe), when you start bending those short flanges against it.  I could also go back to .047 which would make a huge difference.  In fact, with a little thought to adding stiffening gussets to the underside and securing the batery well, 20 gauge (.035) would do the job.

As for the larger flanges, all straight sections are bent, including the two upturned flanges, one of which is curved.  All the corners for the downturned flanges are welded on.  After everything was in place and welded up, I used a air board file with ceramic abrasive to level off the bottom of the cutout flanges.  That made a huge difference to the appearance of the underside; although, you'll notice I didn't show a picture of the bottom of the shelf.  Between all the various hammer, chisel, and blunt objects marks, welds I couldn't quite get to grind to my satisfaction, and the bluing from heating, it looks a little rough.  Maybe a little spray-on flaw remover (undercoat/bed liner/body filler) would help  😉

[ETI4K]

On 6/17/2021 at 5:17 AM, dutchzcarguy said:

Nice battery tray!  Btw.. i remember that i took it also out of my 240z and later on i screwed it into place.. not original i know but it's handy.. especially when i restore the car for the third time in about 2-3 years i guess... (hope..) (will be my second restore of this car)

Isn't it funny when you come up with a brilliant idea and give yourself a nice pat on the back, and then learn a million other people have already come up with it? 

[zKars]

Excellent work all around. There is a particular joy in creating something from essentially nothing but raw materials.

 I use M5 rivet nuts for my tray removal function. Once you buy a decent rivet tool to set them, they are cheap and easy. I use them all the time for things like replacing all the silly plastic push pins that hold in the plastic interior panels. 

Just to help everyone down the line, don’t forget our friends at KFVintage now have a new battery tray at a very reasonable price.

 

[ETI4K]

That tray looks very nice, and at $100, it's a deal.  So my time was worth $8.50/hr.  😪.  It's a good thing I have plenty of time.

I love the idea of Rivnuts.  Hadn't thought about them.  And it certainly doesn't hurt that I have the tool for setting them. 

 

[Patcon]

All hand made! Very nice! I had wondered if you had a bead roller or something to work the edges with.

[ETI4K]

So this is interesting...

I finally was able to get my motor from the machine shop - 6 months after leaving it with them.  In that time, they cleaned the block and head, honed the cylinders, polished the cam and crank journals, cc'd one chamber, cut one side of the head .007, disassembled the pistons/rods, and balanced the rotating parts (excepts the pistons).  Good thing I'm not in a hurry.

The good news is the cam and crank journals did polish out and are still within spec.  I mic'd the crank at 2.1536 and 1.9573 (they had been cut .010 previously).

   

More good news, the cylinders cleaned up as well.  No machine work needed anywhere.  I had also taken the BHJ damper to them to hone the bore for the required .0010 - .0015 interference fit.  No machining was needed as the fit was spot on.

Unfortunately, I had to pay for the head to be cleaned and surfaced (cam-side), which they did before I decided to use another head. Some wins, some losses.

 

Now the pistons.  They had told me one piston weighed 19g more than the others and all of them appeared to be identical to one another (so no chunks missing).  After I got them home and cleaned up, I set about finding out why.  So I got out my good digital scale (reads grams to four decimal places) and found it would only read up to 100 grams.

The scale is reading the velocity pressure of the air coming out of the A/C register.  I just happened to have caught it at .0005.  It has a glass cover, but one panel is missing so I just keep it off.

 

 

Interestingly, the machine shop only balances to 1g.  I was told trying to balance to .1g was "way, way overkill."  I told him that was okay.  It's my motor and it'll be my time, AND it'll be free.  Since free is affordable, I'll be balancing as close as I can to .1g - for fun if nothing else.  I guess I'll have to confirm the balance of the connecting rods they did while I'm at it.

Just for fun, I weighed the pins which were still oily.  I zeroed the scale and weighed the first pin.  After removing it from the scale, I noticed the display did not zero.  There was a swipe of oil on the platter.  I cleaned off the oil and then placed one drop from a needle oiler on the platter.  It weighed .0089g.   I am sure this is VERY useful information.  😁

 

I then got out the bigger scale, but it would only read to .01 pounds, so no good since it can only resolve to 4.54 grams.  It would easily identify that there's a difference but not what that difference is at the level of detail I want.

Note the difference in weight on this scale: .04 lbs which is 18g. 

  

 

Finally, I went to my balance.  I don't have weights for it so I can't get the actual weight, but I can get the delta between pistons.

 

First I found the heaviest one (which turned out to be #4) by placing one on each pan.  Then I left #4 on the pan and started with #1 on the other.  To that pan I added small objects (paper clips and twist ties) until the pans balanced, then measured the added weights.  I didn't spend a lot of time on the ones that were close in weight to #4 - I was looking for the lightest one.  The lightest one (#2) was off from #4 by 22.09g.  I'm guessing the difference between my measurement and theirs is attributable to them weighing while still oily and with crown deposits.  By the way, this is what 22 grams of added weight looks like.

 

 

Now, the shop owner, the machinist, and I have examined all the pistons with some level of care.  I don't know if they did what I did and compared #2 to #4 as that would most likely illuminate the physical difference(s).  While they were not able to explain the difference at all, I found at least one thing different between them, though it's not enough to account for the total difference.  There are two small divots on each side of the piston flanking the pin axis.  It's really hard to see in the pics, but one piston has them as divots and one has three of them as through holes.  Anyone wanna weigh in on other likely causes? 🙄  Yes, I did just write that.

Please ignore the R and L marks.  Go by the position in the pictures. 

BTW, these are ITM pistons.  Excerpted from their website and highlighted by me...

"ITM Engine Components, Inc. is a wholesale distributor and importer of internal engine components for passenger vehicles and light trucks. We have over forty years experience in the automotive aftermarket...Because ITM is one of the first importers, we have many great and longstanding relationships with manufacturers from around the world. Communication between the manufacturers and ITM, is a very thorough process ensuring that ITM is providing our customers with the best possible components at competitive pricing.  The components we distribute meet or exceed OEM specifications for quality. Many of these components are manufactured by the same factories that are contracted by the original equipment auto makers."

I just got a cold chill down my spine.

 

 

 

 

 

 

 

[Zed Head]

22/418= 5.3%  Is that a lot?  How much do the connecting rods differ?