Tuesday, February 27, 2018

Around the Rim (Part 3)

Today's post continues the saga of upgrading the rims on the '78 MGB from the crummy chromeys to some mid-90's Honda alloys.

Clean, Clean Again
original Honda rims
After 30 years of use, and very little in terms of care, these new-to-me rims needed some love. First, they needed to be cleaned. I started with some basic car wash, a scrub brush and a hose. This worked some, but there was some stubborn brake dust and other grime on the insides. This took brake cleaner and some 150-grit sandpaper, but I was able to get down to some silver. I washed them a third time, this time with dish soap and a scrubby sponge in my kitchen sink (Boo puts up with so much). Once cleaned up, we could really get a look at what I'd bought.

Assess the Damage
Two of the rims were in fairly good condition. There wasn't much in terns of curb rash around the outer edges, and there were only a few scrapes from what looked like applying snow chains. The other two rims, however, had been in a few fights. There were some small chunks chipped out nearest the rubber, and many many gouges in that outer edge as well. Sadly, there were some deeper wedge-shaped scrapes in the face where, again, it looked like the rubber strap for tire chains had been put on possibly wrong such that the loops dug into the rim.

Plan the Work
The damage, though, was purely cosmetic. I was able to add air, and the air held in all 4 tires. Since the damage was surface, I knew I could repair it, but I felt I would need to paint rather than restore to plain aluminum. I'm sure there are others out there who can repair aluminum such that it looks like the damage was never there. That's not me.

paint concept (upper right)
To fix the chips and gouges, I thought about brazing alumi-weld into the gouges, and then polishing. Alternatively, I could use Lab Metal. I've used that stuff before, and it really does finish nicely, but I'm not convinced that it will leave the exactly right color. I suppose I could mix aluminum dust from sanding the rim into the mix for coloring if I really wanted to retain the all-aluminum look. After looking at the rim on the car, I think adding some color would look better, especially since there is a very limited amount of chrome on the car.

So, I planned to repair the chips and gouges with Lab Metal, and paint the outer lip and the mag-face, leaving an inner rim and the insides of the mags the original aluminum. This would bring out some of the chrome while not having an overwhelming amount of it. I mocked up a few options in paint so I could get a sense of how it would look and then I got started. First, you need to get down to the bare aluminum.

Take off that Clear Coat
on-car paint concept
The Interweb is a great resource, but some advice just isn't that good. While some is wrong, other advice can just be ill-suited to either your skills or project. For example, there appear to be many folks advocating removing the factory clear coat by sanding until what you're removing shifts from white to grey. Then you know you're down to the aluminum. While this does work, it takes an incredible amount of time. If you try to short-cut the time by using a lower grit (like 60 instead of the recommended 100), the car part will get deeper gouges that need to be sanded off with higher grit. In the end, I'm not sure if much time gets saved. I tried this method with one wheel. Since clear coat is not applied uniformly, you will hit grey while also still removing coating. In the end, I think this method was a bust, and don't suggest it.

For the other 3 rims (and I came back and did the sanded rim too), I used airplane stripper. C had some from when he was stripping the paint off the 280ZX, so I knew it worked and worked well. At least on paint. I knew that it didn't damage rubber when little drips got on it. I laid out the three rims, and brushed stripper on one wheel at a time. Once I got done brushing the third rim, the first was about dry, so I applied a second coat. Doing all four wheels would have timed out just about perfectly. Once the second coat was dry, I attacked the rims with steel wool. The clear coating scrubbed right off, leaving the bare rim with little flecks of clear coat left behind. To get completely cleared, I used a razorblade scraper. The airplane stripper was significantly faster and left behind a better surface. I hosed the rims off, and they were ready for the next step: fixing the damage. I'll get into that next time.

Thanks, as always, for following along. More next time-

Tuesday, February 20, 2018

Around the Rim (Part 2)

Today's post continues the saga of rotating the rims around the various cars in the yard so we can get rid of the donor ZX we picked up a few weeks ago. This time, I focused on the spacer to get the replacement rims for the MGB (from a mid 90's Honda Accord) to fit.

Space Case
1" spacer added
ET and backspace are kind of confusing topics. To really get it, you first need to imagine the rim and consider that the spot where the rim bolts to the hub is almost never at the centerpoint between the outer and inner edges of the rim. The ET (Einpress Tiefe) is the distance in mm between that centerpoint and the spot where it actually bolts to the hub. This measurement is interesting and important when calculating how well different rims will fit. It gets more complicated as you change the wheel width. I have spent lots of time trying to figure this out (see Wheels, Studs, Chrome and Backspace), deciphering the RAtwell page on tires, and finally building a spreadsheet to help me compare rims and tires. If you have the measurements for your wheel arches, and suspension, you can jump straight into the 1010Tires offset calculator. I've played with that thing quite a bit while trying to figure out what rims I could fit on the old bus. Of course, I didn't discover it until after I'd spent hours building and refining a spreadsheet calculator. Ha! And after all that, I just bought a set of 16" rims from a guy who had them on a Vanagon (See New Shoes), so I didn't have to test my spreadsheet or other measurements in the end.


rear view w/spacer
Anyway, I believe that the ET for the crummy chromes is lower (moving the rim further out) than the stock MGB rim and much lower than the Honda Accord rim. Or the other way: the Honda ET is higher than the MGB rim which is higher than the ZX. Even if we factor in that the Honda rim is an inch wider, the offset/ET is actually a bigger factor in the math, based on the pictures.

I didn't take pictures showing how close to the wheel arch the crummy chrome rims are, but the rubber on the wheel just barely extends out past the outer edge of the arch. In the photo in my last post, you can just make out the front tire and see how it is pretty far out towards the wheel arch. Technically, this isn't legal, but with the way big trucks are allowed to drive around with tires multiple inches out past the wheel arch, I guess the traffic cops have bigger issues to handle. I can support that.

The Honda Accord rims, on the other hand, are pretty recessed into the well when compared to the old crummys. I have at least an inch of space before I'm getting near the wheel arch, and as you could see from the picture on my last post, I couldn't even get my index finger between the rubber and the spring.

Math? Why Math?
spacer on, better fills wheel well
So, after all that figuring, thinking and prior planning I'd done before, you'd think I would use the same cautious approach to solving this need. Nope. Instead, I hit the eBarf and found a set of 1-inch thick aluminum integrated-lug wheel spacers for $85US delivered. My logic:
1) I need a good inch between the rubber and the spring.
2) I have at least an inch between the rubber and the wheel arch.
3) There is nothing in the front suspension, hub nor wheel arch that is more restrictive than the rear spring to rear wheel arch.
So, if I can get a rim into the rear wheel well with one of these spacers and it doesn't rub (and it shouldn't), then we can get all 4 mounted without issue. As you can see from the top picture, there's much more room for the tire on the inside and from the middle picture, it doesn't protrude out past the wheel arch on the outside. Barely. They look right on the car now.

Now that I have proven that they can fit, and look nice in their native state, I'll be spending the next wheel-related post walking through my steps and experiments to clean them up. That's it for today. Its a little short since it's my birthday. Have a great week and as always, thanks for following along-

Tuesday, February 13, 2018

Around the Rim (Part 1)

Today's post looks at rotating tires, one set at a time and some planning / thinking around how to rotate tires from car to car, ending up in a better place than where we started when the music stops. This got really long, so I'm splitting it up into sections (again). Today, we'll focus on how this rim job got started.

The Catalyst
rusty rim
A couple months back, I pulled out the studded snow tires and my floor jack, to get Flash the Jetta ready to be our snow tank when winter turned nasty. While I swapped my 3-season tires for my studded snows, I got thinking about how we were going to finish the stripping work on the donor, and then getting the remaining shell removed. "If we pull the wheels, how will they get it out of here," I asked myself. By the time I'd gotten the winter tires on the Jetta, and the 3-season tires stored, I thought I had a plan.

My Logic
When we got the part-donor 280ZX, it was originally because C wanted the rims. I did a little research and found that most of the time when you have a yard pick up a scrap car, they give you less money if the car doesn't have wheels. I guess this is because they can't use their usual tricks to get the car, and someone has to pay for the nuisance. That someone is you. The interweb says that there are some yards that simply won't accept a junk car without wheels. I'm not fully sure that's true because sometimes the Interweb is wrong, but with that thought, I started thinking about how we could resolve a potential rim shortage.

The 280ZX and the MGB run the same size rim: 4 holes by 4.5 inches (or 114.3mm) apart. The backspace / ET is different, but they are close enough that they mostly fit each other. In fact, I'm fairly sure the rims currently on the MGB are 280Z aftermarket rims. But they're crummy fake wire-spoke rims that has the chrome flaking off, leaving large rust swathes around the lugs (see picure above). They're awful, and within a few days of getting the MGB I decided I wanted to replace them. To avoid possible junk-yard-wont-take-it issues, we're going to put them on the donor ZX. With that settled, the MGB will need rims before the donor shell gets removed. Well, the rims on the keeper 280ZX would fit, but as I described in the post about how we got the donor car (See 280ZX*2=Y), they just aren't our style. We are going to keep the smaller front rim/tires as a spare for each of our cars (one each 280ZX, MGB). This leaves us short one set after we move the donor ZX rims onto the keeper 280ZX and the crummy chromies from the MGB to the donor.

The Rims
Honda rim
I hadn't intended to keep those crummy chromy rims in the MGB anyway. I'd been looking, but original-looking aftermarket rims are, like $175US each. I'd been leaning towards getting a set from Acme Speed Shop, but I needed to corral $800US to make that happen. Knowing that simply wasn't going to happen soon, and having rims would enable us to ship the donor to the wrecker.... I went a different way. I had been trolling craigslist like I do when I stumbled upon a set of alloys that used to ride on the mid-90's Honda Accord. They looked okay in the posting, and the seller assured me they held air, so I took off to nab them. $100 later, I have a set of rims (with trash rubber) I can put on the MGB. I didn't go into this blindly. There is a great resource on the MG Experience identifying rims that fit. I figured with a savings of nearly $700US, I could clean up the Honda set, maybe apply some paint and still be ahead cost-wise. Or, I could just clean them up and sell them to fund one of those Acme sets.

Test Fit First
This sounds obvious, but so often we'll get all excited about something and tear right into the doing without first checking to see if what we're about to do makes any sense. Case-in-point, I could have started repairing on the curb-rash before even checking that the rims even fit. Again, the Interweb sometimes is just wrong. Okay, maybe I did get excited a little. But, it was no more than a few minutes of cleaning before I realized that I hadn't verified the linked resource. So, I pulled off the rear passenger (right) side wheel and slapped on one of the new-to-me Honda rims. The bolt-pattern was a perfect fit, so with very little wrestling the rim was on, nutted down and on the ground. So far so good in terms of the linked resource.

crummy chrome backspace
I took one of the other new-to-me Honda rims and set it next to and then on top of the crummy chromy rim I'd removed. The rubber (tire width) is about an inch thicker with the new rim, which aligns with what I was expecting. The new rim is 15" diameter and 6" thick. The one I removed was 14" diameter and 5" thick. The thicker rim supports a wider tire, so checking clearance both at the leaf spring and at the wheel arch is important.

Offset
As you can see from the pictures, the crummy chrome rims sat much further out towards the wheel arch than these Honda rims. There is almost 3" between the leaf spring and the tire sidewall. In contrast, the Honda rims sit quite close to the leaf springs, so close I can't even fit my index finger in-between the spring and the tire (see the lower picture). This leads me to believe that I am going to need spacers to center the rim between the leaf spring and the wheel arch. Spacers aren't nearly as expensive as I'd feared, running $10US per corner for off-the-shelf spacers. I just need to determine how much space I need and then figure out what lug nuts I need to make sure there's enough thread to hold the rims on well. To clarify... consider that the lug bolt (stud) is a fixed length and the more space you put between the hub and the backside of your rim, you are potentially taking away threads. The holes in the spacers for the lug studs are usually loose enough for you to get extension nuts that will thread between the spacer and the stud so you can still use most of the stud threading to hold on your rim. This takes care. If the extension on the nut is too long, you will bottom-out before the nut can be torqued on. If you use a nut that has too little (or no) extension, there may not be enough thread to safely hold your rim on.

Honda backspace
Or, there are slightly more expensive spacers which have lug studs integrated into them. T got a set of these when he was going to fit old (80's) Mercedes rims onto his not-quite-as-old (90's) Subaru. In fact, I used one of them to make the camping table attach to my spare on the bus (See Camping Table) after he got rid of that old Subbie. This style also lets you change the bolt pattern, if you want. You could run 5-lug rims on a 4-lug car without a whole lot of work. The upside for my application is that the spacer is nutted down onto the hub and the rim is then nutted down onto the spacer. This leaves plenty of meat on the respective lug studs to make sure your wheels are on safely. I have found 4-wheel sets delivered for under $100US, so while it's more than double the slide-on style I described first, if you add in the expense of getting the right lug nuts to be safe, the prices could nearly wash-out. Plus the added headache of time lost getting one set only to need something different, etc. Of course, the sense of security that comes from knowing that your wheel isn't going to fall off makes the decision much easier. I just need to figure out the right amount of backspace. I'll address that next.

That's it for today. Thanks, as always, for following along-

Tuesday, February 6, 2018

New Year, New Tools

Over the course of the last 6 months or so, we've picked up some new skills and a couple new bigger shop tools to power them. Today's post goes over some.

Power-Washer
Boo power washing back deck
About a year ago, Boo wanted to power-wash our concrete. You read that right: she wanted to. She was not asking me to do it nor solve for it; she wanted to be the person doing the washing. She looked at renting one, and they run around $300 per day. On a whim, she looked at the Bi-Mart mailer, and they were selling them for, get this, $295. So, she went and got it, got a 2-gallon of gasoline and power washed the rear deck, the back patio, the front side walk and some of the driveway. She has since used it on the back patio again, and I'll be washing the siding when the weather warms back up. I've thought about how I could use this tool on the cars, but figured it would probably do more damage than anything. I've read about folks using a power washer to strip paint. I may experiment with that when I re-paint the bumpers on Hapy.

MIG
Set for floor, I think
If you've been reading this blog, you know that over the Summer of 2017 (read: MGB - floor pans 1, 2, and 3), we played with a MIG. It all started when we discovered floor-rot in the MGB. To resolve, we borrowed a MIG from our good friend Travis. He is a welder by trade and has a few of them at his disposal. Truth-be-told, he'd rather have a TIG welder, but the MIG is so handy (or appropriate) for some jobs, that it will soon be back in his shop. We really had fun, and have used it on a few smaller things since the floors. While we don't expect to use it on the Z or again on the MGB, there's always a use for a welder. Once it goes back to Travis, I'll be adding it to my list of tools to add once i have space.

Soda Blaster
C wanted to get the paint off the Z. He started with a grinder. That's dirty, but dry. And loud. And slow. Then, he tried Airplane Paint Stripper. Still dirty, but wet. And nasty-stinky. But a little faster. We have watched videos and television shows on Velocity where the project car rolls in, gets taken apart and then "sent off to blasting". After the commercial, the car comes back completely stripped of paint and rust. Sometimes the body is in pretty good shape, but usually the blasting exposes all of the history: old dents which were "cave and paved", rust that ate through and interesting cheap body shop repairs. Seeing that magic, we figured we wanted to get some of that.

HF Soda Blaster
First, we looked at renting one. These run at $325US a day, and the only outfit around here is an hour across town. So, we could get up at 6:AM, pick it up at 7:AM, be home by 8:AM and then blast until 3:30 when we tear the machine down, pack it up and haul back over to the rental shop which closes promptly at 5:PM. Arriving after 5 means you pay an additional day. So for 7.5 hours, the rental runs at around $46.50 an hour, and that assumes you don't stop for lunch. AND, you need to buy your own soda (at $40US per 50# bag). Blasting an entire car would probably take 3 bags, so at this point, one fun day of soda blasting (plus 4 hours of combined travel time) is just under $450US.

When we bought the power washer, it was virtually the same thing as what we would have rented. Clearly, that was a good move. The soda blaster, however, is a little different. The fancy rental was almost 3 times what a Harbor Freight blaster cost ($135US), so we bought one, with a dead-man valve and some extra nozzles. And a 50# bag of large soda.

The nozzle on our blaster is really small, and while it does effectively remove paint or grime from metal, it is much slower than I expected. In doing research, I've learned that these are much slower than sand-blasting, and that's by design: the soda is much less harsh both on the environment and on the target material. We have decided that the soda blaster is probably best suited for sensitive areas where you can't get after the paint with a grinder. We may circle-back and try the power washer too, to see if we get better results in shorter time with that. One last concern is the need to properly treat the metal which was stripped by the soda. The soda changes the surface pH, which helps prevent rust, but also gets in the way of paint or primer adhering to it. There are a few different ways to solve for this, but first pressure wash the soda-blasted areas to get all of the residue off. Then, it is recommended to use something like HoldTight 102 to address the pH shift.

Capacity Reached
I've mentioned our limited space, and while it's a "first-world problem", it's still a problem. We are now leveraging a small garden shed for storing thing, like the power washer and the soda blaster. I think the acquisition of any new large tools will need to wait at least until we are down to one car in the garage. We may need to consider a larger shop somehow.

That's it for this week. Thanks as always for following along. I think I'll have made sufficient traction on one or more of the projects to be able to get back to posting on them.