Metal Blasting & Metal Preparation
When I popped the hood of the El Camino for the first time in years, I was aghast.
Its valve covers were rusty, the carburetor was covered in corrosion, and even the chrome air cleaner had spots of car cancer on it.
It had really gotten bad. As I've stated before, it's no longer a vehicle my Grandfather would have driven. This thing is going to require an entire restoration. But, it isn't just any restoration, it's my Grandfather's El Camino, which means special care has to be taken to save as many parts as possible — not merely those that are necessary or convenient. Even at considerable expense, I'll be saving every component I can in order to keep the car he drove on the road as he drove it. Replacement parts simply won't do for this job — not unless there is absolutely no other way. So, no replacement valve covers, carburetor, or air cleaner. No replacement fasteners. No paint scheme changes. Nothing. It'll even have 205/75/R14 white wall tires and the original steel wheels with the original hubcaps because that's how he drove it.
In order to do that, the El Camino's parts are going to need some rust removal and refinishing. While I'm already experienced with that kind of work, I want to make sure this is done right; so, more knowledge is a good thing. Enter Media Blasting & Metal Preparation by Matt Joseph — another CarTech title. I've been really impressed by a number of their books recently, and I've been looking forward to this one for a while.
Let me start off by saying this book is fascinating. Matt Joseph and I see eye-to-eye on quite a bit when it comes to cleaning and metal prep. He's put together one heckuva guide and I can tell you it's going to make a real impact on how I approach repairing the deterioration on the El Camino — not to mention my other projects (most notably, the Survivor).
I've spent years testing metal preparation methods — mostly those geared toward the limited means and circumstances I've had to deal with in the past. While I achieved some success finding effective methods during the time I was rebuilding the LX and restoring the Survivor, nothing I used was what I'd call "efficient." Everything was relatively expensive and very time consuming.
As I've learned from reading Media Blasting & Metal Preparation, there are certainly situations for those kinds of methods, but there are also processes and procedures that are more efficient and do a superior job when used appropriately.
Going forward, I'll be using the knowledge I've gained from this book to better leverage my time and money. For me, there weren't any new methods, equipment, or supplies discussed, here — in fact, I know quite a few more from my own research and experimentation — but, the strategies and tactics explained, are going to make an enormous difference.
Of course, the methods described in the pages of this short tome do require special equipment, tools, and space, but at this point, I'm no longer naive enough to think those kinds of needs are circumnavigable.
If I've piqued your interest, follow along to see what Media Blasting & Metal Preparation has to offer:
Chapter 1: Basic Metal Cleaning Considerations
To read it from Matt Joseph, metal cleaning is a war on contamination more than anything. In Chapter 1 he goes into great detail describing what that war looks like, the weapons you have to fight it with, and the realistic outcomes you're looking for.
That last part, realistic, is an important part of this chapter — and the rest of the book. Although just an introduction to the concepts of metal, contamination, and preparation, Chapter 1 does a fantastic job of setting up and defining a very pragmatic foundation for understanding how to prep various metals and how to put the information in the rest of the book into useful context.
Chapter 2: Basic Approaches to Cleaning Metal
The key to effectively cleaning metal is to know how to do it.
I realize that wisdom isn't much of a gem, but Chapter 2 goes a long way towards giving you that know how with an introduction to all the basic processes for metal cleaning. It explains, in detail, what those methods are and why different situations have unique requirements — even where the methods come from. The processes described include liquid parts cleaning, electrolytic stripping, mechanical abrasives, and blast cleaning systems.
Chapter 3: Alternative Approaches to Cleaning Metal
Chapter 3 starts out by looking closely at cleaning metal with water. I know, crazy, right? I mean with the availability and effectiveness of detergents, solvents, and acids, what does water really have to offer?
The truth: almost everything.
This chapter explains how water can be used to effectively clean metal with both pressure washing and steam cleaning. The key, here, is "effectively." We're not talking about going to the hardware store, picking up a little electric pressure washer and trying it out to see what happens — we're talking about the science behind the effect that water in its various forms has on metal contaminants.
Chapter 3 also looks at the uses and effectiveness of other industrial cleaning methods such as soda blasting, wet media blasting, cryo blasting, vibratory and tumble cleaning, molten salt bath cleaning, and hot galvanizing.
Yeah, that was my thought, too. But, apparently, not only is hot galvanizing a coating, the process is also a contaminant remover for metal. So, check it out for more information.
Chapter 4: Choosing the Best Cleaning Process
Obviously, the best way to choose a cleaning process is by gaining methodical experience, but Chapter 4 will set you up with what you need to know to get that experience without destroying everything you touch. While it provides some specific options for unique circumstances like iron, steel, aluminum, and even delicate cast bronze, it provides you with something even better: an understanding of the factors that dictate your choices. Let's face it, you probably won't find a book filled with every potential scenario you could get into — and certainly not one that's only 144 pages long — but Media Blasting & Metal Preparation does a great job getting you ready to tackle your projects, none-the-less.
Chapter 5: Frank Weinert, Master Blaster and Man About Cars
Chapter 5 is all about proper media blasting technique for steel automotive body panels. It covers the five steps used by media blasting expert Frank Weinert. The steps are as follows:
- Step 1: Pre-clean parts to remove dirt, grease, and oils.
- Step 2: Soda blast parts to remove paint and loose rust.
- Step 3: Quartz sandblast parts to remove strongly adhered rust and stubborn paint.
- Step 4: Mechanically remove any remaining contaminants.
- Step 5: Protect panels for storage.
I bet you think I just gave away the author's prized cow.
I didn't even give away the most significant part of this chapter. The real treasure still awaits you. The detail and value of the information in Chapter 5 is immense and is far more involved than that brief list — and, truth be told, if all you do is follow that list without any explanation, you'll likely end up with warped or more severely damaged parts. I have some experience stripping parts with media blasting, but not like this and it opened my eyes to the possibilities — also, the need for space, equipment, and practice, but that's just part and parcel of the automotive hobby. Especially me with mine.
Chapter 6: Choosing Abrasive Blasting Materials
Although you'll find important anecdotes and advice for choosing media throughout the book, Chapter 6 focuses on the choices and explains the factors that influence media decisions, as well as the media types to choose from.
Here are the factors:
- Media recycling potential
- Substrate damage potential
- Substrate surface finish
- Media cost
- Health and safety
This is the only chapter where I feel it would be nice if a little something was added: specifically, addressing the issues with using each media type and what media types work best on which substrates and with which types of contaminant removal needs. As an example, including a detailed explanation of an earlier warning about using aluminum oxide on steel or steel on aluminum — because of the complication of electrolytic corrosion. Another bit of information I feel would be useful is a detailed explanation of which kinds of media could potentially contain silicone, which can cause problems with contamination and create issues with finishing. Lastly, in the section on health and safety, an explanation of which media types will and won't cause silicosis of the lungs, would be very beneficial.
Moving, on, the blasting media types covered with their own sections include the following:
- Agricultural abrasives
- Mineral abrasives
- Slag byproducts
- Aluminum oxide
- Baking soda
- Glass and ceramic bead
Other media types discussed anecdotally:
- Silicon carbide
- Ground glass
- Steel shot
- Steel grit
Lastly, although intentionally overlooked, I think this chapter would benefit from a detailed explanation of mechanical abrasives and tumbling media, as well.
Chapter 7: Abrasive Blasting Equipment, Supplies and Accessories
Chapter 7 compares and contrasts industrial and consumer-grade blasting paraphernalia. Specifically, it focuses on two companies, Clemco and Eastwood, but it also gives you general guidelines for choosing blasting equipment, supplies, and accessories — it even provides some insight into finding used equipment and building your own.
Another useful part of this chapter is a section on blasting a car frame with consumer-grade equipment — it also compares it to the professional process used in Chapter 5.
While it might sound like this is just an advertisement for two blasting equipment companies, it's a bit more than that. Using these two suppliers and their offerings as examples provides a very practical look at what matters when choosing equipment and how to do it to get the results you're looking for.
Chapter 8: My Conclusions
Based on the title of Chapter 8 and the fact that it's only eight pages long, you might be tempted to think that this is just a summary of the book and ignore it.
I don't recommend skipping this chapter.
While it is a bit of a summary, it also dispenses the all-important skills of component diagnosis and appropriate cleaning method application in one cohesive process. It's the critical culmination of the information in the rest of the book that, when all-combined, gives this volume its real value: the ability to make a good decision through understanding the metal cleaning issues you're facing and how to judge them so that you can handle them correctly.
If you think you don't need to care about the level of metal prep in this book, you're wrong.
There, I said it. I meant it.
Many of the issues faced by restorers aren't things that an automobile manufacturer has to deal with, but, many are and the reason the manufacturers achieve quality results with their finishes isn't just the more expensive processes available to them, but understanding the need for proper substrate preparation and what that is. This book makes that information available to the average enthusiast and professional restorer, alike, but, it does so from the perspective of our practical, unique needs. And by that, I mean, within our limited capabilities, from the position of starting with old, used, and often deteriorated metals, with a focus on the outcomes we need to achieve to be successful.
When I picked up Media Blasting & Metal Preparation, I was already well versed in the concepts behind metal prep, but I've definitely come away with a better understanding of the process as a whole. As author Matt Joseph makes note of, this information is fragmented and incohesive out there in the rest of the world — and cohesion makes for context, which makes for better understanding: that's what this book provides.
Unless you're working in the fields of theoretical and applied sciences that deal with substrate preparation, this information is hard to come by, but Media Blasting & Metal Preparation makes it accessible to everyone and really does earn the moniker on its cover of "a Complete Guide." In my opinion, it's a must read for every automotive hobbiest and repair professional.
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