GF grip fasteners coming loose / how hard do I need to tighten these things?

[1sascha]

Already posted this one over on the HOTAS discord but it seems I'm the only one who ran into this problem, so I'll repost here:

A couple of weeks ago I experienced some weird behavior from my MCG Pro: Pushing the stick quickly to some of its extremes would trigger my button 29 (brake lever turned to button in VKB Config) in games. Went into VKB Config and Windows Joystick CP and behavior was repeatable there too... hard pull on the stick would light up button 29. Took off the grip and realized that the dust-cover wasn't sitting 100% properly around the gimbal's "connecting rod". So I guessed that the rubber cover was getting between the grip and the gimbal somehow and messing with the connection between the two. Re-seated the dust-cover properly around the gimbal's rod and problem went away.

Then a few days ago I added a 100mm extension to the stick. Everything worked fine the first few days but then that button was getting triggered again while flying. Confirmed the behavior again in VKB Config, and this time I also checked the black box and saw that the green LED was on as if everything was ok. Dust cover wasn't the problem this time. I took off the extension, put the grip on without the extension and problem was gone. However: When I took everything apart, I realized that the lower grip fastener (between gimbal and extension) was looser than when I had last tightened it down - meaning it felt like the fastener had started to loosen itself from two or three days of daily flying.

After all that, I started to re-assemble everything again, making doubly sure everything was tightened down *really* hard this time and that I was pushing down first on the extension and then on the grip when I fastened things down. In fact, I usually use a screw-driver type bit-holder to tighten the fasteners, applying as much force as I can through that thing. This time I went and used an Ikea-style Allen key, using the longer side as my lever to get maximum torque/leverage onto the screw and tightened both fasteners down *real* hard. I mean.. they're both on so tight now that I doubt I'd be able to loosen them with my bit-holder driver.

Problem hasn't come back yet and I'm not really worried about damaging things, since both the fastener and the gimbal's connecting rod are metal, but: Is that how it's supposed to be? Also: can these fasteners come loose on their own just by using the stick? If so: Should I put some Loctite on the fasteners' screws before tightening things down?


S.

[Drano]

I wouldn't think that would just come loose like that. You're sure you have the rusks lined up with the angled sides facing the shaft? I have a 200mm extension on mine and have never had one loosen up. I don't think I have them at Hercules tight. Maybe something is off with the fitting? VKB would probably just send you one? Definitely not the kind of thing that you'd find at a hardware store. The screw might be though. Could try another screw. You could try a lock washer under the screw head side. That's a hardware store item.

If you go the loctite route look for the lightest strength possible. I believe it's purple. That's a really small screw so even if you used blue that might be too strong. If it got stuck and you stripped out the Allen head trying to turn it, now you're having to drill it just to get it apart again. Red is right out! Don't use red on that small of a fastener.

[1sascha]

Not sure about that. I bought the stick back in August, and even though it has a Sept 2020 production date, it was new when I first started using it. So wear and tear seems doubtful. The connecting parts (both on the grip side and on the gimbal) look fine to me and, of course, the pad on the gimbal does have a few imprints from the grip's pins on it, but it doesn't look damaged or anything.

I do make sure that the fastener is in there properly - if it isn't aligned properly I can't even get the grip or extension to slide into place, so this is pretty much a mandatory check before I re-assemble things.. Not sure if this is the correct way of doing it, but I insert the fastener "assembled" into the grip's or extension's hole, then make sure it's aligned properly in there and then slide the grip or the extension into place. The way the thing starts to "bite" once you screw it down is also pretty unmistakable, so I am rather sure the fasteners are sitting as they should.

I have blue Loctite here (medium strength, the purple stuff is hard to find for some reason in local HW-stores). Since I use that stuff for my stainless-steel bracelets on my dive-watches, I have done a bit of research and according to the manufacturer, the glue's strength is only about 50% when applied to stainless steel. Not sure if that's what the fastener is made of though, but from my experience a bit of heat (like, hair-dryer hot) usually loosens the threadlocker nicely. That said: I don't really want to have to take that route - perhaps I should take some pics tomorrow and show them here to check that there isn't something messed up with the fasteners or the gimbal that I may be overlooking.

I think for now I'll keep checking the fasteners more regularly to see if they really come undone now that I've tightened them quite a bit more than before.



S.

[Drano]

The purple stuff is usually a gunsmith thing so that's why you wouldn't generally find it in a hardware store. I just checked on mine. Bet I haven't had the stick apart in over a year and they're both good and tight. Pins all springing?

[1sascha]

Haven't actually checked that yet. For the time being, the ghost-button thing hasn't returned (yet?), so I'm kinda reluctant to take the grip and extension off the gimbal..

Guess I'll start looking for some longer wooden toothpicks or something to reach in there since I doubt I could reach those pins in the grip (or in the extension) with my fingers and I wouldn't want to touch them anyway. Thing is though that this has happened both before I even owned the extension and now with the extension on. Although that first time was probably down to the rubber dust-cover somehow getting in the way of the grip/gimbal connection.


I probably should have mentioned that the first time this happened, button 29 firing was just the first button-malfunction to show up. After a few minutes, other buttons/hats on the grip started to behave weirdly - like certain hat position either not working at all or triggering the wrong button response. All of which leads me to believe that the grip wasn't connected properly to the gimbal. Didn't check the LED on the black box that first time this happened - cause I'm a bit dumb, I guess.



I did check both fasteners' tightness after my daily sim-session last night and they seemed as tight as when I had last fastened them.

Fingers crossed, I guess?


S.

[1sascha]

Well.. it happened again. As usual, it started very "slowly" - last night while flying I had one or two button 29 "misfires" and when I examined the stick today, the lower fastener (extension to gimbal, which is the one that originally came with the stick) was quite loose again - and I had screwed it down super tight last time, like I said earlier. The other fastener (grip to extension) is the one that came with the extension and thus newer/less used. It was still on very tight when I checked it.

I examined the contact pad and the lower fastener and didn't see anything wrong there. The fastener does have some sort of "imprint" indentations visible on the oblique bits where it contacts the gimbal's "rod" (must be from those teeth/serrations on that part of the gimbal), but it didn't look or feel damaged to me.

I also checked the springiness of both the extension's and the grip's pins and they too seemed fine to me.






I took a clean and soft brush to the gimbal before re-assembling everything (looks downright filthy at this level of magnification, yuck! ), and things seem to be ok again .... for now.


I am at a bit of a loss here. I had checked the fasteners tightness just two days ago and it still seemed fine to me, but it must've come loose again during last night's gaming session.



S.

[Ron61]

Perhaps they abut against each other when tightened. Therefore, you can grind a little in this place.
Well, the contact pads can be tinned with solder.

[Drano]

Your pads look quite savaged!

[1sascha]

That's pretty much what they looked like from day 1 - after a few instances of taking off/putting on the grip of course. I only own one grip, so I don't swap things around regularly, but any changes to the gimbal (springs, cams, clutches) pretty much require removal of the grip, so I don't see how this could be avoided with this sort of system. This is from roughly four months of owning the stick from new and from what I've seen from other GF-owners, their pads didn't look much else. Yes: It looks a bit worse than a couple of months ago, but that's just from taking off/re-installing the grip a half a dozen times or so between then and now.

I got an answer over on discord and it turns out this might be down to a very simple piece, namely the spring washer in the grip fastener - I hadn't even realized there was one in there, lol. Which would make sense, because whenever I tighten the grip down, everything works fine and every time I started getting these "misfires", the fastener would be way looser than when I had tightened it down. I did check the washer and its two ends weren't really on two different planes, but rather it looked more like a flat, open ring. I bent it a bit back into shape, but I also opened a support ticket with a request for a replacement washer. Until this gets resolved, I guess I'll just have to check the fastener's tightness before every flight-session.


S.

[Drano]

Maybe grab another lock washer at a hardware store. It's a tiny one so it'd only be a few cents.

[Ron61]

There is a simple rule for bolts and growers - if the bolt is in tension, break - the grower is not installed, it is prohibited.
If the bolt is shearing, a grover is placed to prevent the nut from unwinding. We have the first case.

[Drano]

Without having mine in front of me right now. Off the top of my head, another difference I think between my MKI Rev.A Gunfighter base is that the shaft on mine doesn't have the knurls on it yours does. Mine is smooth. But my rusk bolts have never just worked themselves loose either at the base or top of my 200mm extension. I can say the few times I've taken it apart my contact pads don't look nearly as gouged up as yours do. Wondering what might even cause it. Sascha, is your stick a twisty? That might do it if you're constantly applying a twisting motion. You'd think the knurls on the shaft would stop that.

[1sascha]

Nope... don't need a twisty since I use pedals. Besides: I doubt the twisty-motion would move the pins against the pad. That would be just asking for trouble if it was built that way.

I guess those additional indentations on my pad are a bit more recent, since I installed the extension twisted to the left initially, but now I went back to having the extension on the gimbal "centered" and the grip mounted to the extension twisted as far to the left as the mounting system allows. I fly center-stick, so I need the grip mounted offset like that. I did experiment a bit with various ways of mounting the stick and extension "twisted", so that's probably where those additional mark on the gimbal come from. On a side note: The contact pad on the extension looks still totally unused - perhaps it's a different material than the one used on my gimbal... it does look more silvery in color than my goldish/cooper-y looking pad on the gimbal.

Again: I don't think there's anything wrong with the pad, despite its look in the pics. I've had the grip on the gimbal for two gaming sessions now and I've had zero misfires or any other malfunctions. And since every time these misfires have started to happen, the grip fastener was coming loose, I'm fairly convinced that the problem is with the fastener not holding the grip as securely as it should. I mean... it even says "tighten grip before flight" on the GF's base. I always thought that was just a goofy allusion to real life warning-labels on aircraft, but I guess it's there for a reason...

There is a simple rule for bolts and growers - if the bolt is in tension, break - the grower is not installed, it is prohibited.
If the bolt is shearing, a grover is placed to prevent the nut from unwinding. We have the first case.

I have no idea what you are trying to say.

S.

[Ron61]

What do not you understand?
In retaining crackers, the screw works in tension - that's why Grover's washer (engraver) is not needed there. We had cases when the grip was not rigidly fixed even when tightening this screw with a tube-amplifier on the hex. And the reason was in contact with each other crackers. It was corrected with a file, a needle file, literally 0.5 mm had to be ground off.

[Drano]

Ron, I think that what you're saying is being lost in the translation to English. I'm not getting it either.

Edit. Upon reading it a few times, I think I have what you're saying.

I think what Ron means is the points on the rusks are meeting when your tighten the screw. This shouldn't be happening. Since they're tightening against each other rather than against the shaft individually. His cure was to file off a bit of the point of each rusk.so that they'd stop meeting when tight.

Ron, I think that's what you're saying here and, of course, it makes perfect sense that would cause the problem.