Glassbeading DW hub bars

[CLS447]

What do you(anybody) think about glassbeading the hub on the DW blades. I really would hate to try to polish them!

[CLS447]

Has anybody tried it yet?

Here are my 3 DW hubs that could use a nice finish.

[gyropilot]

Chris,

I can't see any problem with glass bead blasting something as thick as a hub bar. It would in no way weaken it, and in fact it should have a beneficial effect. Glass bead blasting can relieve surface stresses on a part, which in theory, can help prevent cracks from forming.

Here's something I found on the web from a company that specializes in glass bead blasting and shot peening:

Surface Improvement - Steel Shot Peening or Glass Bead Peening

The surface of all metal parts contain some degree of micro-cracking, tiny cracks, discontinuities or even tool marks that can be a source of failure. When a metal part is stressed and subjected to cyclic loading these micro-cracks enlarge and propagate through the part. At some point in time the part will fail. Normally, tensile stresses concentrates at the top or bottom of crack during loading. However, the compressive skin created by peening tends to cancel out the tensile stresses and the cracks do not propagate.

Cyclic fatigue failures generally begin at the surface defects or stress concentrations known as stress raisers. Examples of high stress areas are machine marks, scratches, corners or holes, fillets, keyways, splines or other changes and interruptions in the smooth surfaces of metal. Peening improves fatigue life, strength, operation and corrosion resistance. Reliability of parts is enhanced as this treatment provides repeatedly uniform finishes, surface durability and wearing qualities.

All surface stresses and most internal stresses can be relieved by peening. Surface stresses resulting from ordinary machining operations may be transformed into hard-wearing compressive stresses.

Precision Cleaning - Glass Bead Peening or Blasting

The Precision Cleaning carried out by Hi - Tech Blasting uses the media of spherical glass beads. This method of cleaning is a way to remove all foreign matter from metal, such as scale, corrosion, paint, carbon and epoxy. Glass bead blasting prepares parts for assembly or for plating, anodizing, painting or coating. A freshly bead blasted surface is beautifully clean and has a slight sheen. It totally replaces brushing, grinding and chemical cleaning methods. Complex items can be easily cleaned by glass bead impact blasting.

Glass beads are spherical, they do not have a cutting action. They will therefore remove contamination and finish surfaces without destroying critical working tolerances. The process of glass bead blasting produces a beneficial effect of improving the surface finish of cast, machined or rough surface components. Micro pores of metal are closed in all metals, particularly effective on aluminum and die cast products.

After glass bead blasting your parts, I would recommend washing with soap and water, chemical etching, followed by an Alodine coating. The result would be gold colored parts protected from corrosion.

Have fun,

John L.

[CLS447]

Thank's alot John ! I'm gonna glass bead them.

[Brian Jackson]

John, do you have a link to the source? Thanks.

Brian Jackson

[gyropilot]

I didn't save the link Brian, but I think that particular company was in Australia.

Just do a quick Google (http://www.google.com) search on something like "glass bead blasting surface stress" and you'll get tons of useful information.

Regards,

John L.

[MikeBoyette]

Chris,
Are you just swapping blades between the three hubs? Just wondering because the blades and hub bars are a match set. If you are just swapping then you probably end up with a shake since the blades were balanced with only one of the hubs. Unlike other manufatures Dad balances the blades as a unit therefore when you mix and match hubs and blades you could end up with a mess. Just wanted to inform you. As for the glass beading it should be fine just stay away from the bolts.

[CLS447]

Mike I really like the 28' blades your dad sold me. I bought the extra hubs privately for later experiments. All I have done so far was to see if the holes lined up. They all lined up in every configuration.

I know your dad doesn't recommend this but I hope to someday try the other hubs with my blades. I realize that balancing & tracking adjustments will have to be made.

I would like to try them as 29' on my 2 place & as 25' on the KB-2 with SUB 81 that I am going to be building this winter.

Any input would be appreciated.

Thanks for your concern , Mike.

[MikeBoyette]

Chris,
I am all for experimentation, but realize this will void your warranty. LOL. Just kidding. I just wanted to make you aware of the possible problems that may come up while running mismatched hubs and blades. good luck.

[Friendly]

So what are you going to coat them with after glass beading.??

[scottessex]

I think a nice RED anodized hub bar sure would look good on your gyro!

You could glass bead them and hit them with some clearcoat, or some spraybomb.

I painted my old hub bar silver, but it didn't last long enough (with the crash and all) to see if it protected it from corrosion

[CLS447]

I'm trying to save time & money. I am just going to look into the alodine that John suggested in his post. Either that or just some spray oil.