Manufacturing Aluminum Masts

[Mikey2]

^^ Agreed.

1. Aluminum 6061 Billets are melted down and extruded through the mast cross section die.
2. The extrusion is then cut to the length required.
3. The top end would be cut and tapered and welded.
4. Any other holes and fixings would be cut out.
5. Then it is heat treated and quenched.
6. The mast would then be anodized.
7. Mast would be prepped (alodine wash, zinc chromate primer, undercoat, LP paint).
8. Final finish coat applied: Awlgrip.
9. Any screw holes chased.

How about that then?

only around the taper, there should not be any welding elsewhere
Al Al loses abt 60 % of its strength abt the weld areas

you seem very intense abt this, what are your goals, ?

[Mikey2]

Originally Posted by lazeyjack

you seem very intense abt this, what are your goals, ?

I'm doing an essay on the production of the mast, looking at the manufacturing methods used, and the quality control checks carried out.

Thank you for your help so far, if you have any info on quality control checks carried out then please post

well there are the bend tests, which consist of rolling the metal around a certain diameter, the radii of which is the thickness of the metal x a factor, and I can't remember what that is, plus the standard hardness tests All this should be freely available on various sites, try alcan , perchinay, then the test cert will give the exact proportions in % of each metal, like Ni, CadmiumChrome, magnesium and others It will give the tensile achieved, which must fall within a range

[Mikey2]

Ok thanks, how often is this done? every one in 20?

Anymore?

[Gramp34]

Originally Posted by Mikey2

^^ Agreed.

1. Aluminum 6061 Billets are melted down and extruded through the mast cross section die.
2. The extrusion is then cut to the length required.
3. The top end would be cut and tapered and welded.
4. Any other holes and fixings would be cut out.
5. Then it is heat treated and quenched.
6. The mast would then be anodized.
7. Mast would be prepped (alodine wash, zinc chromate primer, undercoat, LP paint).
8. Final finish coat applied: Awlgrip.
9. Any screw holes chased.

How about that then?

I'd suggest reading about the extrusion process, e.g., at http://www.bonlalum.com/Login/SlsMfg...on_process.jsp, to better understand how the extrusion part is done.

Read up on the heat treatment of aluminum, as well.

Machining is straight forward: sawing, drilling of holes and milling of slots, probably with a woodworking router.

I doubt any heat treatment is done except when the initial extrusion is made. Yes, welding will reduce the strength of the mast in the heat affected zone immediately around the welds, but the welds on tapered masts carry very little load.

Finish is either anodizing or painting. Awlgrip is LP paint.

Quality control of the mast extrusion will be primarily the responsibility of the extruder. They make sure the right alloy is provided, then would certify the mechanical properties (tensile strength, hardness) and dimensions of the extrusion are correct. The sparmaker would need to verify the mast has been made correctly to the customer's engineering drawing, for instance, that hardware is mounted in the correct places, before it is shipped to the customer. If the material has the correct properties and the shape of the parts are correct, there is no need to destructively test (i.e., break) sample masts.

You're in the UK? Why don't you phone (ring up?) some sparmakers there? For instance, look at http://www.zsparsuk.com. They invite people to visit. I'm sure they'd be happy to explain the process to you.

Good luck,

Tim