r2d2

Metal for rack case chassis
« on: October 18, 2017, 08:35:37 AM »
Hello
just to talk a bit about the  type of metal suitable  for rack and consoles chassis ,

thanks for any post about
r.
« Last Edit: October 18, 2017, 11:43:55 AM by r2d2 »
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Re: Metal for rack case chassis
« Reply #1 on: October 18, 2017, 10:05:21 AM »
Helo
just to talk a bit about the  type of metal suitable  for rack and consoles chassis ,

thanks for any post about
r.

you can go with either aluminum, mild steel or stainless steel.
it really depends on your requirements.

aluminum is a soft metal, easy to work with, but it bends and warps easily, can't be tapped because the thread just won't hold out for long. for screws you'll need to press fit some self-clinching nuts. can't hold paint very well regardless of your primer, and paint type (epoxy, lacquer, acrylic, enamel). can't withstand an abusive handling. for a long term durability and scratch resistant, powder coat or anodize it.

mild steel is a low carbon steel, and corrode very easily. at the same thickness as aluminum, mild steel is studier and more rigid. it's easy to work with if you have the right power tools. it can be tapped. with the proper surface treatment,  you can paint with automotive grade paint, regular Krylon/Rust-Oleum spray paint cans, powder coating, and hot/cold/electro galvanizing.

stainless steel doesn't corrode easily. it's harder than mild steel, but only grade #201 has the same rigidness as mild steel (because it has more iron content). most stainless steel stuff usually don't need to be painted, especially if a hairline and reflective surface finish is what you're after.

all of them can be water jet or laser cut for precision. both services are very affordable nowadays if you don't feel like cutting manually with a saw.

abbey road d enfer

Re: Metal for rack case chassis
« Reply #2 on: October 18, 2017, 10:39:53 AM »
Aluminium is one word for many different alloys. Some of them are apt at milling and drilling, but cannot be bent, others are easy to bend but difficult to mill because the metal sticks to the bit.
Aluminium is often used for front panels because they can be thick enough to look good but not too heavy and theycan be anodized.
Steel is often preferred for the rest because it can be bent and tapped; cosmetically it can be zinc plated either witha matt grey finish, or gold-tinted chromate.
Aluminium alloy may be used for extrusions constituting the sides of the chassis.
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r2d2

Re: Metal for rack case chassis
« Reply #3 on: October 18, 2017, 12:00:21 PM »
Aluminium is one word for many different alloys. Some of them are apt at milling and drilling, but cannot be bent, others are easy to bend but difficult to mill because the metal sticks to the bit.
Aluminium is often used for front panels because they can be thick enough to look good but not too heavy and theycan be anodized.
Steel is often preferred for the rest because it can be bent and tapped; cosmetically it can be zinc plated either witha matt grey finish, or gold-tinted chromate.
Aluminium alloy may be used for extrusions constituting the sides of the chassis.

Thanks for reply guys

most of the front panels are aluminum anodized ,
like focusrite red, blue ,
with case chassis top and bottom chromate ,

most summit audio have the chassis zinc plated , top and bottom covers included ,

dbx "core" series compressors seem painted steel in all parts (front and chassis)

about consoles chassis , better steel or aluminum , or both mixed , for "Rfi" isolation , ground issues etc ?
r.

..... Cracking D.Vader Firewall ...  II-)

ruffrecords

Re: Metal for rack case chassis
« Reply #4 on: October 18, 2017, 12:09:33 PM »
you can go with either aluminum, mild steel or stainless steel.
it really depends on your requirements.

aluminum is a soft metal, easy to work with, but it bends and warps easily, can't be tapped because the thread just won't hold out for long.

Only thin aluminium panel cannot be tapped. All pro mixers are made from aluminium extrusion based frames which are tapped and work well.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

r2d2

Re: Metal for rack case chassis
« Reply #5 on: October 18, 2017, 01:18:27 PM »
…..All pro mixers are made from aluminium extrusion based frames which are tapped and work well.
Cheers
Ian

it is standard "60-60" aluminum or  some custom type ?
r.
..... Cracking D.Vader Firewall ...  II-)

ruffrecords

Re: Metal for rack case chassis
« Reply #6 on: October 18, 2017, 03:37:09 PM »
it is standard "60-60" aluminum or  some custom type ?
r.

It can vary. The cheaper sub-racks I have seen - with no special EMDC properties - use an unspecified alloy. More expensive EMC capable sub-racks use different alloys often with a conductive coating such as Alocrom 1000 to improve shielding. Manufacturers do not generally specify which alloys they use.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'