Engine cleaning: Powder Coating VS. Glass Beading

[Anonymous]

I continue to hear different opinions regarding which method is best for cleaning oxidized engines: Powder Coating VS. Glass Beading.

What is your take on this? Trying to decided which to have done on my 1980 Suzuki GS1100E engine.

Rudi

[Anonymous]

Powder coating is a coating used instead of paint, after the engine is cleaned. It is not a cleaning process as such.

Bead blasting is used to clean the parts. Bead blasting is really the same process as sand blasting, just with glass beads instead of sand as the abrasive media. The way it works is an air hose is set up with a nozzle that directs a very high velocity stream of air. Then a feed system is added that dribbles the beads (or sand, or whatever) into the air flow. The beads are carried along by the air and when they hit the object you are blasting, they scrub off whatever is on the surface. The true name for the process is just "blasting", and the media is specified separately.

The reason for the different media choices is that some are more aggressive and some less. Sand is about as aggressive as it gets and will happily remove aluminum as well as the grime and oxidation. It works well for steel, but nothing softer. Glass beads are the traditional less aggressive media used for aluminum and other softer materials that sand will damage. It works well, but is expensive. There are alternatives to the glass beads, such as slag materials (nickel, and other metals) and some plastic materials which cost less and work OK. For really delicate surfaces, ground walnut shells are used but it is very expensive to buy.

Tips for getting blasting done:

1. Wash the pieces first. Grease will come off, but it makes a big mess and takes way longer than if washed with soap or solvent first to remove the easy stuff. It does not have to be perfect, but remove the large gobs and junk as a minimum. Your blaster will thank you if stuff is degreased before he touches it.

2. Plug EVERY hole, orifice, opening etc. The media gets EVERYWHERE in nooks and crannies and is a bitch to get out, so be anal about taping openings and bolt holes before blasting. Heavy duct tape works pretty good for this.

3. After it is blasted, wash everything thoroughly to remove the grit that got inside anyway. This is especially important for engine components. It is a good idea to run a tap into all of the threaded holes to ensure they are clear. This also applies after getting paint done, for the same reason.

4. If your parts are steel (such as a frame, swingarm or triple clamps), prime them immediately after you get them back. Blasted steel is very subsceptible to rusting and will quickly form a layer of surface rust that will mess up any paint job. This is especially important in the more humid climates, as bare steel can rust in only a few hours after blasting is completed.


Mark

[Anonymous]

What a glass-beader told me...

Tell me what you think about this statement. It was from a business that does glass-beading of engines.

(my question was why he thought powder-coating was a bad idea...which we previously wrote)

"powdercoating will deteriorate over time plus it will harm all the
gasket surfaces. clear powdercoat over alum in not a good plan
either."

What he writes goes against everything good I've heard about powder coating...

Anyone have an opinion?

Thanks!
Rudi

[Hap Call]

Welcome back Rudi!!!

I'm glad you are asking this question....I'm in the process of rebuilding a spare engine and would like to know!

Hap

[Anonymous]

"powdercoating will deteriorate over time plus it will harm all the
gasket surfaces. clear powdercoat over alum in not a good plan
either."

What he writes goes against everything good I've heard about powder coating...

Anyone have an opinion?

Of course powdercoating will deteriorate over time, as will every other coating/paint you can put on. The only thing that might not deteriorate is anodizing, but I am not familar enough with it to say. Powder coating is one of the toughest, longest wearing coatings available.

I am not sure why it would deteriorate a gasket surface. It should not be applied to a precision surface at all, whether a gasket sealing surface, bearing fit or threaded hole. This applies to ALL coatings, not just PC. If the powder coat will deteriorate a gasket surface, then it should also deteriorate the rest of the aluminum it is applied to - and it doesn't.

I am also not sure why he would say clear powder over aluminum is bad - it is used everywhere in industry and commercial products to protect aluminum with no problems at all. Maybe he has a vested interest in pointing you in some other direction or process?


Mark

[sharpy]

engine

Hey try acid dipping. COMPLETE stripping is required. Then paint with VHT universal aluminium paint for a near perfect finish. Bottom half of engine cases are not painted as standard

[Anonymous]

Hey try acid dipping

I would be very cautious about trying this with aluminum parts. Aluminum is very reactive and will disappear when immersed in most (if not all) acids. It would be fine for steel parts, however. An alternative to this is hot tanking in caustic soda (NaOH), also for steel only. Hot tanking does a great job of cleaning up steel for coating. The cautions about surface rust forming quickly also apply to steel prepared by either of these methods, as well as blasting.

Mark

[Anonymous]

Try www.coatingspecialties.com I am going to get the 80gs1000e wheels powder coated and perhaps clear coated done there come springtime or sooner. They have lots of experience and list prices. Harley parts are like 30 to 40% more for the same procedures....hahahahaha!