Glock: Aluminum Grade?

[neena]

What would be the best grade of aluminum for the absolute best pitch on a Glock?  I assume it's really more critical on a glockenspiel than a vibraphone, since you don't have resonators or motorized fans helping the tone. 
In the online ad for these plans about vibraphones, there are 3 types mentioned, something like T4, T5 & T6.  I'm also wondering if using a different (cheaper) type of aluminum will be a lot different to work with as far as sanding, etc… later when I make the vibraphone.

[Jim McCarthy]

Hi Neena
Well it all depends - strictly speaking a pro grade glock is generally made with steel bars rather than aluminium. There are aluminium gloacks made and in those cases it applies much the same as it would for a vibraphone. The SG simple glockenspiel mentioned in the makeamarimba.com website is exactly that - a simple instrument, and as such it does use aluminium bars - and what sort matters very little. If you want a pro glock though go with thicker steel bars.

For the vibes - well it is not quite true that the material is less critical - it is true that the bars do have resonators to amplify the sound - but because of the lower pitch range they also require it more. The fans will not really help the tone in any way - they just provide the vibrato effect.

For a vibraphone the T number - which is temper - can be important - but not as important as the actual alloy type itself. ANY alloty will make a tone - no doubt - but if you want a well known standard - go for 2024 T3 - this is what used to be called "Duralumin" in the old days in the aircraft industry, and it is the exact alloy that Musser have/do use for their vibraphones. A very common grade of aluminium in construction is 6061 - usually either T5 or T6. Both are ok - they are more corrosion resistant and heat tolerant than the 2024 - but not quite as strong and in my opinion the tone is not QUITE as good. The high copper content in 2024 is what provides the strength and sustain. In 6061, the primary alloying componants are silicone and magnesium I think it is - hence the resistance to corrosion and lower tensile strength..... the sustain you get there is more about the temper - a harder temper in that case is best.

Hope that helps!
Jim

[neena]

Hi Jim-
    I guess I should clarify that I want to make the glockenspiel to practice working with aluminum before I attempt to make the vibraphone. 
    I know how much better steel sounds on a glock than aluminum, but I don't want to work with steel yet.
     So.. I just want to make the nicest tone for a glock possible (with aluminum) since  I already  have a couple tinny-sounding cheap student models.
     If I understand your post correctly, using 2024 T3 for both the glock and the vibes would make the nicest tone that aluminum can produce.  Am I right?

[Jim McCarthy]

Well yes I would definitely recomend the 2024 in your situation then. As previously mentioned the "simple glock" guide is really aimed at a result probably similar to those less than awesome instruments you already have. Don't get me wrong it works fine - but its concept was as a simple and inexpensive instrument rather than a pro sounding one. The PV vibes is a different story and you can get a pro result there of course. If you want to get a truly pro glock sound - I would also reccomend slightly longer bar sizes - particularly in the top end - so you would have to work out a new "graduation" of bar lengths - and thicker stock also - go for at least 1/4" thick metal and anything up to 1/2".

[neena]

Thanks for your suggestions Jim!

I'm afraid I'll be asking a lot of questions as I muddle through these building processes.

Back to the subject of cheaper aluminum glocks, I own two:

One has bars that are 1" wide and uncoated. 

The other has bars that are 1 1/4" wide and they have a matte ceramic finish that I believe is baked on them.  Interestingly enough, the glock. with the ceramic finish has a much nicer tone that decays more quickly, which I prefer.  I wonder if this is due to the ceramic coating or the width of the bars....  I believe the thickness of the bars is the same.... 1/4".

I guess I'm really after making the ultimate thrifty glock.  I'm going to try for bars 1 1/4" wide (because the target area is bigger and makes them easier to play) and go for a two and a half octave range, starting on the F below the C that the plans start on, and ending on three C's above that low F.