Cam wear after a week or two

[wolph]

Hi all,

I've recently purchased a Gunfighter Mk3 with Kosmosima. It's a great stick! However I've always felt it's not as smooth as it should be around the center, and it's always felt a little "grindy".

After the first day of noticing this I swapped to soft space cams and tried various springs & damper settings but never could tune it out.

After a few days I noticed a little bit of wear on the cams in the form of scratches where the bearings roll near near/over the detent. I look again today and both cams are clearly showing wear & discoloration in this same spot. I've only been using it about a week.

The stick is great - I've already ordered a second one. But I'm just wondering is this normal? Have I done something to cause this? will I have ongoing problems due to the discoloration?

Any help is appreciated I'd really love to get rid of the grinding feeling, as it's preventing me from truly enjoying the stick.

Of course please let me know if more info is needed, or any photos of specific things etc... I only removed 1x cam to show the wear, but both cams are showing the same wear.

[Ron61]

These are not wear and tear, but traces of processing after manufacturing.
After galvanizing, the surface is treated to eliminate unevenness. Don't worry, it's okay.

[wolph]

Thanks.

However (and I may be completely wrong!) this looks like the old style of Mk2 steel cam? Shouldn't I have received the new style Aluminium cams on a Mk3? I purchased about 2 weeks ago via Ali express. I have another coming from Ali which I assume will have the same cams, and will wear in the same way. The base says Mk3 and the box has a Sept 2020 manufacture date.

The centre still feels grindy and not smooth, and only when the bearing touches these worn down bits. It doesn't stop me from using it but surely it shouldn't be like this for what otherwise is an amazing stick? (and very expensive to buy from Southern Hemisphere)

Can this be fixed with Aluminium cams ? Do I need to sandpaper the cam to smooth it out? Do I need to lube the cam?

I'm pretty keen to get it resolved. Hoping I don't have to just get used to a grinding sensation every time I pass through centre on either axis.

Hope you can understand! I realise the good construction of the stick & base means this (and most things) can be fixed, so I am definitely not complaining and am very happy to own a Gunfighter, I'm just trying to get it resolved! I've spent A LOT of time taking the base apart & tweaking things from day 1 to try fix it. It feels pretty clear to me these worn down parts are causing the grinding sensations.

Note exactly the same issue for another person on reddit with a new gunfighter: https://www.reddit.com/r/hotas/comments ... n_comment/

[wolph]

Also as pointed out in the reddit thread, the cams are sticking to magnets which implies they are steel and not Aluminium.

Looking forward to hearing the next steps!

(and to confirm - there's no ill will on my part. I'm extremely happy with the gunfighter and already recommended it to various people looking to upgrade their sticks. I imagine I'll be even happier once this is resolved!)

[fallout9]

Hi Wolph. Try installing some other cams set and see if you get the same grinding feeling. The cams definitely don't need to get lubrication.
About the new cams: VKB always improves their products; it's been decided that the new double coated stainless steel alloy is better than the original MKIII aluminum cams. And no, they're not the MKII cams, the #10 and #30 - those were different technology and design.

[wolph]

Hi Fallout,

Thank you for clarifying about the cams! I did wonder if you guys had bailed on the Alu cams!

As for the grinding feeling - I will try another cam. I haven't yet done this.

The cam in question though is looking worse for wear than in those pictures - it's now got a pretty rough edge where the grinding is.

But as above, I will try another cam and report back!

[wolph]

Hi - Just an update.

I haven't tried a new cam yet, but in the meantime I think I've figured out the grinding.

As the wear on the cams (shown in my initial post) continues to actively take place there is metal dust & shavings generated as the cam is worn down. This metal dust builds up on the cam itself and also the bearing - This is easy to spot as a black build up on the bearing & cam. If I open up the base and clean the cams & bearing with a cotton bud it becomes smooth again.

The cotton bud is picking up black metal dust, and I can also see some metal shavings in the bottom of the gunfighter chassis (including some copper colored shavings).

I assume the cam will eventually wear down enough and an equilibrium will be reached - but I wonder if there's any worth in grinding/smoothing down the cam surface myself to quicken the process ? If so, what's the best approach for that?

Just FYI, in case it occurs for others using these Gen 3 cams. Another question - Is it possible to purchase the Gen1 or even Gen2 cams?

[fallout9]

There's no way the contact between the cam and bearing to generate metal shavings if they're properly adjusted. There've been cases where a nut was loose on the bolt securing the cam and the cam was grinding against the metal frame. Check your device again for anything like it; most definitely there shouldn't be any metal shavings or residue showing up in a properly functioning unit. You could use this video as reference: https://youtu.be/xRVab9Hq40Y

[wolph]

Hi Fallout,

Thanks for your reply!

It seems to be happening with my Cam & Bearing, unfortunately.

I checked the cam nut yesterday when I opened the base up to clean them and they were tight. The bearing travels the cam well, and the cam has freedom of movement (but not tight enough to stop the cam/bearing/bolt/nut rotate as one unit. I tightened these till I started getting some resistance then went a little bit further and stopped. The cam cannot move 'sideways').

I'm fairly sure the cam isn't grinding on anything it shouldn't, but I will check. It's pretty clear the shavings are specifically being generated between the bearing and cam, anyway. From memory when running my finger along the cam edge where the bearing touches it does feel rough & sharp - but that's from memory, I will open it up again and verify.

I'm not really sure what else I can check - I have already watched that video many many times to ensure I have installed things correctly (I've spent A LOT of time trying to ensure the issue is not due to something I've done - This is still extremely possible of course!)

The trickiest thing seems to be around how much to actually tighten the nut on the cam - Mine is about as tight as in the video you've attached.

I'll open up the base today and take another picture of the cam, and we can see how it's changed since the original post. I also have a second gunfighter that I changed the cams on and it's nice and smooth.

Love my gunfighters by the way, despite this issue! I will update again later!

[Drano]

You say the cam is traveling on the bearing well. But is the outer bearing rolling along the cam surface as it moves or is the cam just sliding along it? That outer part of the bearing, the part that contacts the cam, should rotate along the cam surface as the gimbal is moved. If it's not, there might be a problem with the bearing. While it might appear to be moving smoothly, and it would as the surfaces are machined with some lube on them, if the bearing isn't moving that would certainly wear the cam. The bearing is steel where the cam is aluminum, a far softer metal.

Just a theory as I'm not looking at it operate. Take a look at that. I can't think of anything else on the assembly that would wear that quickly if everything was working properly. Something ain't right there.

[wolph]

I will look at this specifically & report back. Thanks for chiming in!

[wolph]

There's no way the contact between the cam and bearing to generate metal shavings if they're properly adjusted. There've been cases where a nut was loose on the bolt securing the cam and the cam was grinding against the metal frame. Check your device again for anything like it; most definitely there shouldn't be any metal shavings or residue showing up in a properly functioning unit. You could use this video as reference: https://youtu.be/xRVab9Hq40Y

Hi Fallout,

Just an update.

I swapped cams from Space S to Avia S a week or so ago and immediately the same axis still felt 'grindy'. The other axis feels OK. Looking at the Avia S cam today it is starting to see some of the same wear in the same spot as the space cams.. something really doesn't seem right

Please note all I've done with this right stick is swap cams. I did the same cam swap work with my left stick and it's totally perfect & smooth. The left stick has no issues and frankly feels like a Ferrari in my hands The right stick hasn't felt like this from day 1. I don't think it's anything I've done.

Also note I've contacted my dealer (Ali express) about it in case they are able to help. It's still within the 90 day return period, so I guess at worst it can be replaced - I use these sticks every day though, so I don't want to be without one

Anyway, any further help on the issue is greatly appreciated, otherwise I can update when I hear from Ali express.

[wolph]

You say the cam is traveling on the bearing well. But is the outer bearing rolling along the cam surface as it moves or is the cam just sliding along it? That outer part of the bearing, the part that contacts the cam, should rotate along the cam surface as the gimbal is moved. If it's not, there might be a problem with the bearing. While it might appear to be moving smoothly, and it would as the surfaces are machined with some lube on them, if the bearing isn't moving that would certainly wear the cam. The bearing is steel where the cam is aluminum, a far softer metal.

Just a theory as I'm not looking at it operate. Take a look at that. I can't think of anything else on the assembly that would wear that quickly if everything was working properly. Something ain't right there.

Hi there!

The cam is spinning throughout it's travel of the cam, as would be expected!

Please see my other post if you're interested in other updates.

Thanks again for your help have a great day!

[wolph]

Hello, I hope everyone is well

Just dropping in for an update.

I've been in contact with Ali express support and they've suggested sanding down the cam a bit with sand paper to polish it - I will do this, but before doing that I tried adjusting the 'height' of the bearing so it will avoid these worn down areas by adding an extra washer, as per the pic below.

The bearing now extends about 1mm over the cam edge (looks more than 1mm in photo due to angle), but now that the bearing avoids the worn down areas of the cam it's a lot smoother and feels good. I guess this makes sense!

However we can see in the photo the bearing is starting to create new grinds (see the straight line on the cam).

I will also follow support's advice and polish the cam surface a little bit - I'll adjust the bearing back to where it was once I've done this.

Anyway, I bought these sticks to last for many years - I guess I'm still wondering if I need to be concerned about this? or shall I just ignore it and get on with my life?

It does seem like the bearing is causing extra damage to the cam, especially for a new item.... but it may be a non issue, but it may also mean I need to look at repairs to a cam or maybe a bearing sooner than expected.

Keen to hear any opinions that are far more informed than mine

[fallout9]

Hi Wolph. As much as I can say by looking at the photo it seems that the bearing is well outside the cam and that's not good (the bearing should be inside the cam on its whole travel range); I might be wrong as the angle is tricky and in this case please ignore this message.