Brass or aluminium filter?

[DavidKKHansen]

I've always been using Heliopan branded filters for all my lenses, the metal ring being made of brass.

Though recently using a filter on my Ricoh GR21 (30.5mm filter) the threads have become damaged when I tried to take the filter off. The threads seems to somehow become "squished/flattened" so now when I try to screw in the filter I can keep turning and turning the filter ring and it'll still feel lose.

Which got me thinking: Is aluminium (or steel) filters more desired when using filter of that small size? Any brands you guys can recommend?

 

[Moto-Uno]

If using threaded filters it's usually best to use dissimilar metals,if I have to use
aluminum on aluminum I apply a very small wipe of anti-seize on the male thread. The caveat here is VERY Small wipe. Peter

 

[Shac]

I've been led to understand that brass has a bit more natural "lubricant" than other metals such as aluminum or steel.
How tight was the filter attached to the Ricoh? - seems strange it would affect the threads when being removed.

 

[Jack Sparrow]

Brass, every time. But it's important not to over-tighten, regardless of material!

 

[Roger Hicks]

Use (1) dissimilar metals but (2) brass whenever possible -- remembering that anodized aluminium doesn't behave anything like the pure metal or even like untreated light alloys.

Cheers,

R.

 

[sevo]

If using threaded filters it's usually best to use dissimilar metals,if I have to use
aluminum on aluminum I apply a very small wipe of anti-seize on the male thread. The caveat here is VERY Small wipe. Peter

Dissimilar metals will create extra issues in case of corrosion (notably electrochemical acceleration of the same). They can bind or come loose (depending on whether the different temperature coefficients work in- or outwards) after being subjected to changing temperatures. And if they bind, the thread made out of the weaker material will give way - undesirable in the case of aluminium lens bodies, where every filter from a dissimilar metal will be stronger.

Personally I tend towards using either brass-on-whatever or the same metal (with the exception that I try to avoid aluminium-on-aluminium, which has seizing and corrosion issues of its own, unless at least one thread is fully anodized), plus judicious application of anti seize. The latter needs not be copper paste, unless you want to be able to retrieve the filter even if the camera should ever catch fire - copper paste is a high temperature anti-seize for use on stoves, motors and the like. PTFE, graphite or any non-creeping, non-hardening grease will do just as well, and may cause less of a mess.

 

[DavidKKHansen]

Thanks for the super fast replies everyone!

I usually don't tighten my filters that much but in the case of the Ricoh GR21 I might have done just that, due to the fact that I carried it in my pocket (baggy jeans). I do remember reading somewhere that brass is either self lubricating with itself or with aluminium, so it makes sense to use brass on the Ricoh GR21 as it seems the female filter thread is aluminium or of similar alloy.

In a pathetic attempt to get a new filter I've e-mailed Heliopan to replace/repair my 6-month old filter, but I'll probably just have to buy another 30.5mm filter off of them.

 

[bsdunek]

If using threaded filters it's usually best to use dissimilar metals,if I have to use
aluminum on aluminum I apply a very small wipe of anti-seize on the male thread. The caveat here is VERY Small wipe. Peter

This is a great idea. Metal to metal can give problems, especially with aluminum. The plastic rim filters don't stick, but the threads aren't very durable.

 

[icebear]

B&W filters have brass but your Heliopan filters are also well regarded. I assume the lens thread was damaged before you screwed in the 30.5mm filter or the filter thread does exactely properly match the lens thread. Anyway brass is the material of choice. Aluminum is just too soft and can stick like no tomorrow.

 

[DavidKKHansen]

How cool! I just got an e-mail from Heliopan that I can send it to them and they'll repair the filter. Will update the thread once I get it back.

 

[DavidKKHansen]

I forgot to update this thread that I've been given a new filter from Heliopan for free.

Yeah yeah, I know, it's just a filter. But last I checked Heliopan filters weren't been given out by dealers for free, so if anyone finds themselves in a similar situation, drop the manufacture a line and perhaps they can offer you good service too!