The glue-and-snips F200 d-pad mod

[gruso]

This is the d-pad mod I did on my F200 in March 2008. The posts have been brought over from gp32x.de. I've included other peoples' posts from gp32x where they add to the information.

Onward then. This is a mod that virtually anyone should be able to do. In short, it involves chopping out the center "crossbar" and fixing it to the four buttons to make one solid pad with a smooth surface.

The first step is to snip out the centre piece (being careful not to wreck it):

Next, the tabs are snipped 2/3 of the way up from the bottom so they splay upwards. This will allow them to follow the angle of the button surface:

Using a soldering iron (I keep a spare tip handy for plastic work), the center piece is "tacked" into place:

Once it's tacked around the sides, it's flipped over and tacked around the bottom. Now it's solid:

Glue is then dripped into the cracks and allowed to dry. Loctite 406 is recommended. Careful not to get any on the top surface of the pad! After drying tidying up with a Dremel, here's the first reassembly:

At this point the opening was not really wide enough, because the pad now needs extra lateral room to pivot. Disassembled, hit it with the Dremel, reassembled, all good. The total size of the opening is only about 1mm bigger (all around) than you see in the above pic. I was worried that I'd have to add a pivot point in the center of the pad too, but it's not needed.

How does it feel? So very nearly like it came from the factory, I even surprised myself. To put a number on it, maybe 85% as good as a bought one. Which is still 100% better than GPH's effort. The button travel is still technically the same, but it certainly feels like less when when your thumb is rolling around on it.

I tested it with Ruckman first for basic 4 directional action, then D1X Rebirth (Descent) for full 3D navigation. It's a winner. [edit] Payback is an absolute dream to play now!


Video: http://www.youtube.com/watch?v=OqJHOOCSFxw

 

[gruso]

Gruso - Just one small question: what stops the actual pad from falling out of the casing? From what I can see the cross-piece holds the sections of the pad in, if you cut that away from the casing (as well as filing away the surrounding hole to allow it to pivot) won't the entire pad just fall out?

That worried me at first, but as it turned out it wasn't an issue. There are three tabs at the bottom of each button which (in unmodded form) sit in little slots, theoretically preventing the buttons from coming out.

After the mod, these tabs become redundant - but the d-pad is still firmly in place. This is thanks to the bulky button membrane underneath:

The rubber "knobs" fit very tightly inside the buttons, requiring some effort to be pushed in. This grip is enough to keep them firmly in place (even more so when the four buttons are joined together). I could probably rip the d-pad out with a big pair of pliers, but I definitely can't do it with my fingers.

I'm getting myself mentally ready to do this mod...Gruso, any other tips or things to be aware of? What tool did you use to snip the cross-section away, BTW?

Some small snips like these: http://www.hobbytools.com.au/prod531.htm

The ones I used were actually a little chunkier than that, which wasn't great. The slimmer/finer the better, so you can get right in against the curved wall and do a clean cut.

TIPS

== News just in - use superglue. ==
Sounds obvious. Because it is. After a week of abuse, my soldered "tacks" were getting a little fatigued. So once the pad is tacked together, some superglue carefully dripped into the cracks will really secure it. You don't want any ending up on the top surface though, so apply carefully.

You *could* just use the glue (and not the soldering iron), but the tacking method allows you to fix a position instantly. So I recommend tacking, then dripping.

== Soldering ==
There is method in the melting. If you just jab it in there you'll probably make a mess.
- Let the iron heat up fully
- Hold the two parts in place, then hold the iron tip against the join location with the gentlest of pressure.
- After 1 to 2 seconds, you'll see, feel and sometimes hear that the surrounding plastic is melting.
- At this point, quickly apply pressure so the tip goes in a couple of mm, withdraw immediately, and blow on the join to cool it. If all goes well, the molten plastic on either side will have set together.

Definitely practice this on some unimportant plastic first. Also, keep a big old rag handy so you can wipe the tip clean after each join.

== Grinding/sanding ==
A Dremel or equivalent is really the only tool for the job. Use the largest cylindrical grinding stone / sandpaper fitting that you have, on the lowest speed. The plastic is very easy to work with.

== Patience ==
Not only while you're doing the job, but once it's reassembled. Because there's a very good chance you'll be pulling it apart again to make that hole just a teeny bit bigger.

 

[gruso]

One more question...

See on this photo, on the casing there's a lip around the edge of the hole, which features the slots that the tabs on the d-pad buttons slot into, and these prevent it from falling out.

My question is, when you dremel away the hole to make it larger to allow the d-pad to pivot, what happens to this lip? Do you have to remove it? Surely it becomes thinner if you're making the hole larger?

Hope that makes sense...

Garn, hack right into the bugger.

The lip will become substantially thinner (~50%) but retains enough strength do its job. The hole has to be at least 2mm bigger (diameter that is, so, 1mm all around if you get me) because the d-pad will be pivoting side to side, as opposed to separate buttons moving up and down. You can achieve this and still keep the lip intact.

... Also, keep in mind that if the d-pad is hitting the case, it's doing so at a pronounced angle. You may only need to sand out an angled section near the top to give it clearance. This can save unnecessary hacking into the lip below. I threw this together in AutoCad:

Guess what! I have another question.

The snippers and super-dupa-extra-strong glue arrived today so I'll be attempting this mod tonight. I just wanted to know how the LCD screen fits into all this - I notice on Dave's opening post there's an image of him removing some kind of connecting ribbon - does the screen stay on the front of the casing or can it be removed?

I don't fancy working on this thing with a piece of sandpaper only cm's away from a delicate screen! But also, I wanna be sure I can do this without leaving loads of dust over the screen. I have a can of compressed air to use, thankfully.

Ah yes. The LCD stays in place for the procedure. You can cut out a cardboard rectangle and tape it over the display to protect it.

As you can see in Dave's pic there are two ribbons. I wasn't sure how to get the big one out, so I didn't. The smaller one just slides out, with some firm-but-gentle assistance. Taking this one out allows more than enough movement to get the job done, but of course you won't be totally free of the PCB while the big one is still attached.

Re-inserting the ribbon is fiddly, but I was able to do it with my large fingers. If I'd had a pigmy friend present it would have been easier.

I found that when I took it apart the second (& third) time for fine adjustments, I got away with not unplugging the ribbon. You'll definitely need that freedom of movement for the initial job though.

 

[gruso]

Duddyroar's result:

Well, I did the mod last night. It didn't exactly go smoothly.

Firstly, just opening this thing up is a task in itself. It took me about 10 minutes to actually get to the stage where I could start work! This is one of the worst designed machines I've ever encountered; I assumed it would be a simple case of removing the screws and popping the front off, but the GP2X is designed to clip and click together, with bits everywhere. Nightmare!

When I actually got around to snipping out the cross section I messed up one side (bugger).

Gluing the d-pad together was an adventure - my glue started to dry out (I used an extra strong glue where you mix two solutions together) so I had to work quickly and the d-pad sections didn't stay in place (this is where you soldering method would work better Gruso, but I don't have an soldiering iron!) so my d-pad now has loads of glue on it and horrible, unsightly fingermarks. sad.gif

Dremelling the hole was fairly easy, but predictably I didn't make it big enough so I had to take it all apart three times in total, which means three times of getting really annoyed trying to get everything to fit back inside the casing. The lip around the hole is completely shagged now, as well (not that it matters).

HOWEVER...

The end result is good. Really good, in fact. I can effortlessly pull of special moves in Street Fighter 2 and games that require smooth, 8-way movement are a joy now. Sometimes the pad doesn't quite detect my downward inputs, but other than that (and the fact that my GP2X looks like it's been attacked by an glue missile) it's all good.

But a word of warning to those of you that aren't used to this stuff (like me) - locate a guide on how to effectively take the GP2X apart because that is the hardest part of the mod, IMO.

Here's what it looks like:

As rough as a badger's arse, basically! tongue.gif AS you can see the hole is a lot wider than in Gruso's pic; to be honest anything smaller than that and the pad hits the side of the casing, which hinders control IMO.

Gruso - the big ribbon is connected via a clamp system, that brown piece of plastic you see can be 'opened' up to release the ribbon. I removed both during work...and getting the small one back in again took me about half an hour. In fact I've put the machine back together and I'm not even sure if that small ribbon is in place.

...

I don't mind admitting to you that I was cursing your name several times last night Gruso, for putting such a stupid idea in my head! biggrin.gif

But yeah, the end result is decent and like you say, a million times better than the original pad. I still think it would benefit from a central pivot point, but I'll be damned if I'm gonna open that bastard up again! Mind you, the hole is big enough for me to just pull the d-pad out now! biggrin.gif

Anyway, all's well that ends well, and now I can actually play Marvel Vs Capcom AND pull of the moves perfectly...that is worth all the pain in the world, IMO!

Footage of Marvel Vs Capcom being played using the Gruso mod! As you can see pulling off fireballs, dragon punches and hurrican kicks is easy, as is peforming Ryu's super combo.

Sorry the footage is so out of focus, I thought it would look better in low light but my digital camera couldn't really cope!

http://www.youtube.com/watch?v=jekUUfkIxcw

 

[gruso]

And another one from Knoxximus:

Today after school, I ran straight to Home Depot and purchased a Dremel, super glue, and sandpaper. I already had a soldering iron. I got home, and since I have opened the GP2X before, I got everything done in less than an hour. Didn't even muck up the d-pad! Works like a CHARM!!

I even got the hole right the 1st time because of how much it was stressed. I used the Dremel for all the sanding...it was also the 1st time I have ever handled a Dremel. Strangely though, I wasn't too nervous. The part I was a little nervous about was the "tacking" of the d-pad with the soldering iron. Didn't wanna melt too much. After that, I drizzled some super glue between the sides of the d-pad where the buttons meet the cross. Was very sparingly with the glue and took extra special care not to mess up the top of the d-pad.