Sand your cam lobes ???

In the following video and another I saw but can't find right now, it is stated that a raw aluminum surface has better grip than an anodized surface.  Is this true? Should one then sand the anodizing off cam lobes? Less likely to walk? I know the metal shouldn’t be heated, i.e. power sanding is out.

https://www.youtube.com/watch?v=_bXEIB_pnvU

The difference is negligent in a real-world scenario (i.e. not a qc lab). Just use your cams and the anodizing will wear off from use soon enough. 

Doesn't really matter to be honest

Friction is one of those things that is much easier to measure than it is to calculate. There are MANY factors involved in friction, and our simple physics 101 equation f=uN doesn't describe the entire situation. So perhaps the calculated value of friction is better with the raw surface. However, as Gavin stated the difference will be negligible. The primary cam holding factor is going to be good placement. And the primary holding force factor will come from the value of the normal force.

And to be clear, you absolutely should NOT sand, or in any other way, modify your cams. 

Use will remove the plating over time.

I've got a set of the dragons (previous version) and it seems like the more I use them, the more anodizing gets added on by the rock.

Are they radioactive? ;-)

 This anodized layer gradually rubs off with use and may even be removed by hand with sandpaper. However, when used exclusively on low-adherence rocks this anodized layer is not easily removed, which means that the Totem Cam may have a diminished holding power, even when it has been used for some time. The Totem Cam’s grip is suitable for all areas once the anodized layer on the cams on the surface in contact with the rock has been completely rubbed off.  

rgold wrote:

 This anodized layer gradually rubs off with use and may even be removed by hand with sandpaper. However, when used exclusively on low-adherence rocks this anodized layer is not easily removed, which means that the Totem Cam may have a diminished holding power, even when it has been used for some time. The Totem Cam’s grip is suitable for all areas once the anodized layer on the cams on the surface in contact with the rock has been completely rubbed off.  

Strongly advise you do NOT follow Rgolds advice. Sanding the lobe could easily change the geometry of the lobe and make the cam ineffective. If you need a cam without anodization there are brands available. The shape of a cam lobe is not something that an average joe whipped up on his garage lathe. It is something that only a CNC machine can properly create. And the fundamental functionality of the cam is based on the lobe geometry.

Rgold you may be correct, but I do not think anyone should be advising people on MP to sand their cam lobes.

grog m aka Greg McKee wrote:

Strongly advise you do NOT follow Rgolds advice. Sanding the lobe could easily change the geometry of the lobe and make the cam ineffective. If you need a cam without anodization there are brands available. The shape of a cam lobe is not something that an average joe whipped up on his garage lathe. It is something that only a CNC machine can properly create. And the fundamental functionality of the cam is based on the lobe geometry.

Rgold you may be correct, but I do not think anyone should be advising people on MP to sand their cam lobes.

I don't think I agree with this Greg,  hand sanding the lobes is definitely not going to significantly change the geometry.  If such a minute difference mattered we'd be replacing cams after a few placements as they get worn/collect dimples.  Most cam manufacturers aren't going to recommend sanding the lobes because of the 1/1,000 guy that tries to do it on a grinder or belt sander.  But hand sanding some anodizing off the lobes isn't going to "change the geometry of the lobe and make the cam ineffective."

I'm not going to sand my cams anytime soon as I climb on granite. However, if a cam manufacturer sees a problem with anodizing, I listen as they are definitely more knowledgeable than the lay man.

Edit: typo

Right---the amount of hand sanding required to remove just the anodizing will have no effect on the cam geometry.   This isn't just my opinion, Totem advised me to sand their anodized cams.

grog m aka Greg McKee wrote:

Strongly advise you do NOT follow Rgolds advice. Sanding the lobe could easily change the geometry of the lobe and make the cam ineffective. If you need a cam without anodization there are brands available. The shape of a cam lobe is not something that an average joe whipped up on his garage lathe. It is something that only a CNC machine can properly create. And the fundamental functionality of the cam is based on the lobe geometry.

Rgold you may be correct, but I do not think anyone should be advising people on MP to sand their cam lobes.

You are way too worried about the shape of the lobes.  You would be sanding less than a 10th of a mm of material off of the surface of the lobe.  But even if you accidentally sanded off more material than that, it would still be fine.  While cams tend to be machined fairly precisely, they are not so sensitive to imperfections.  Think about it...  If the shape of the lobe has to be so precise, then the shape of the crack in which we place cams would also have to be just as precise (smooth and flat).  Small imperfections in the shape of the lobes (e.g. a flat spot) will cause the cam angle to change a bit around that imperfection, but usually only by a few degrees.  micro cams will obviously be more sensitive but again, you shouldn't be sanding off more than a 10th of a mm of material.

As evidence, just look at Metolius UL Master Cams. they have teeth (like little shark fins) cut into them about 7mm apart, and to a depth of almost a mm (that's on a #7).

grog m aka Greg McKee wrote:

Strongly advise you do NOT follow Rgolds advice. Sanding the lobe could easily change the geometry of the lobe and make the cam ineffective. If you need a cam without anodization there are brands available. The shape of a cam lobe is not something that an average joe whipped up on his garage lathe. It is something that only a CNC machine can properly create. And the fundamental functionality of the cam is based on the lobe geometry.

Is your degree in armchair engineering ABET accredited?

Ray Jardine had a CNC machine?

grog m aka Greg McKee wrote:

Strongly advise you do NOT follow Rgolds advice. Sanding the lobe could easily change the geometry of the lobe and make the cam ineffective. 

My sanded BD Ultralight #3 begs to differ. The scratches I subsequently got by using the cam are deeper than any evidence of the sandpapering I did.

Anodizing is less than a thousandth thick, breaking the hard layer wouldn't change the cam geometry.

Look guys, I do not think it is smart to disseminate information that people should be sanding down their cams. If you have some trad experience and know what you are doing then by all means make your gear mods. But having noobs sand down their cams? Come on...all it takes is one inexperienced person sanding too much and the cam function can be altered. 

Totem is asking for trouble by advising people to do that.

And Kyle Tarry, I am a mechanical engineer from CSU, FE certified. Go Rams!

grog m aka Greg McKee wrote:

Look guys, I do not think it is smart to disseminate information that people should be sanding down their cams. If you have some trad experience and know what you are doing then by all means make your gear mods. But having noobs sand down their cams? Come on...all it takes is one inexperienced person sanding too much and the cam function can be altered. 

Totem is asking for trouble by advising people to do that.

And Kyle Tarry, I am a mechanical engineer from CSU class of 2015, FE certified. Go Rams!

Be that as it may, I don't think you should be "correcting" the likes of RGold and the gear manufacturer when it comes to this. Lose the hubris.

How about shaving your nuts?

I definitely should be warning people to be careful about sanding down there cams. I dont know who Rgold is, I have seen him comment good stuff on here. If he wants to sand down cams then by all means. But people should be careful.

I don't know what hubris means. Not going to look it up. 

Note to noobs: beware of cam-sanding madness!   Although cam-sanding is terribly addictive and some people just can't stop until there's nothing left but a polygonal remnant of the original lobe, please remember why you are doing this and cease and desist the instant the anodizing has been removed.