Neo Geo MVS-4-25 v3 Restoration

[Srayer]

I recently picked up a Neo Geo MVS-4-25 v3 from a local collector looking to free up some space in his garage. I've always wanted a Neo Geo cabinet, and this has always been my favorite model. This cabinet and the sound of the Neo Geo splash screen during attract mode are core parts of the arcade experience in my mind.

This cabinet is rough. It was sold as a project machine, and it's definitely that. While I've done tons of arcade repairs and upgrades over the years, I've never done a full restore. I've been looking to take one on, and this cabinet perfectly fits the bill. I'm really bad at photographing and documenting my projects, so I'm starting this restoration thread in hopes that it will force me to do better.

The biggest issue with this cabinet is water damage. The back panels are crumbling and need to be replaced completely. The wood is swollen and falling apart all around the bottom of the cabinet. And it looks like someone was going for the world record of most holes drilled into a coin door panel.

The side panels are in okay shape except for water damage around the edges. The is most evident on the left panel.

The control panel is in okay shape, but pretty beat up. Lots of rust on the inside. It has all the electronic components including the (not pictured) card reader + headphone board. Buttons are pretty crap, but the joysticks are new!

The coin door has been poorly touched up and show some rust. Needs extensive retouching or repainting.

The metal marquee cover looks pretty good! I think I can get away with just touching it up.

The inside is a bit more grim. The speakers are rotting, the mini marquee holder is yellowed, and the light panel isn't working.

 

[Srayer]

It's dusty in there...

...but at least the marquee board looks great!

The monitor has some pretty bad burn-in. You can clearly see a dark rectangle in the middle, and there's text burnt in various places. It's not so noticeable when the display is on, but I'd like to swap it out. Also to be swapped out: this junky, torn up paper shroud.

Speaking of swapping out monitors, it looks like a previous owner did just that. I looked this tube up, and it's a donor tube that came from a television set. Notice that the frame isn't even bolted to the monitor; it's screwed into the cabinet. Nice work, guy.

A dirty but working WG K7400 chassis. There are some issues; colors flicker out and the screen flickers white sometimes. Will recap and reflow, and replace the flyback if there are still problems after that.

The power supply looks to have been replaced lately. Isolation transformer looks a little worn but fine. Most importantly, looks like I got some free tools as part of this deal!

And finally, a fully functional 4-slot board with some carts.

So, that's the overview. Here's my plan:
- Strip all the parts from the cabinet
- Vacuum and clean it out
- Remove side art
- Sand swollen edges of the side panels down
- Cut the bottom few inches of each panel to remove water damage and replace with fresh particle board
- Fill any damage in all panels
- Replace all the panels on the back
- Clean, strip, and paint the control panel and coin door; touch up marquee cover
- Swap monitor tube
- Replace broken or tired parts
- Apply Szabo side art, marquee, CP, and decals
- Reinstall all the things
- Crack a beer and play some Metal Slug

What could possibly go wrong?

 

[Srayer]

I picked up the cabinet last Wednesday, and spent some time working on it over the weekend. Guess what? I did a terrible job of taking pictures of the process. But, here's the work I did, with the few pictures I took.

I stripped and cleaned out the cabinet. Apart from the back panels, there's not too much water damage inside, which is great. I'm not sure what it's supposed to look like in there, but I think the previous owner make some modifications to make the tube donor fit. There's a 2x4 glued and screwed in there below where the monitor sits, and I'm pretty sure that's not stock?

My wife spotted me when I removed the monitor, so I managed not to neck it despite it having no frame. Go us!

After that, I removed all the side art. The black pieces came right off in one piece, no problem. The red pieces were harder. I used a heat gun and a lot of patience to peel them back bit by bit until they were gone. After all the side art was gone, I applied Minwax wood hardener to the damaged edges in preparation for sanding. I also filled the coin door panel holes with wood epoxy (JB Weld KwikWood). I let all that sit overnight.

 

[Srayer]

I started off the next day by picking up a Sanyo DS25320 CRT that I found on Facebook Marketplace. I found some threads online that indicate this tube is a suitable donor for a WG K7400 chassis. Fingers crossed!

After that, I spent a lot of quality time sanding. I have an old Black and Decker Cyclone 2-in-1 detail and random orbit sander. It was slow going at first, because I only had 150 grit paper. I got tired of that pretty quickly, and ran to the hardware store to pick up something coarser. I got some 60 grit sandpaper, which really did the trick! I went around all of the edges, sanding down all the swollen areas until they were flush. I think it turned out great!

It was raining off and on all day, so I would spend some time sanding, then would have to run the cabinet back into the garage. In between sanding sessions, I started cleaning the control panel. It was pretty thoroughly rusted, but I used this Rust-Oleum Rust Dissolver to remove most of the rust. It took four 30 minute treatments, but it was pretty effortless. I also did a first pass at stripping the paint off the top of the panel with Citristrip. That was also pretty effortless; I applied it and let it sit for 30 minutes, then used a scraper to slough the paint off. The control panel still needs a lot of work, but it's a start!

I also cleaned the wire harness. This is pre-cleaning; it doesn't look so bad in the picture, but it's really grimy and sticky. I threw it in the sink and cleaned it with Simple Green and warm water. I then shook and towel dried, then blew out all the connectors with compressed air. Luckily, the sun eventually came out, so I left it out to dry completely.

I spent the rest of the day patching all the damage on the cabinet, which was mostly along the edges. I started with Bondo (the bottom-right in the above photo), but it wasn't working well for me. I was having a really hard time getting it to actually fill the holes on the edges, and it set up really quickly. I switched back to the JB Weld epoxy and that went much better. It goes on pretty thick, but it stays in place and fills really well. And, it sands down pretty easily despite being hard and durable.

 

[Mukuro_W]

Awesome cab, you got a WG K7400 + RCA tube, if it is the same as WG k7000 + zenith tube then you got the best arcade monitor ever made for 15Khz games

 

[Srayer]

Ah, interesting. What makes the K7000+Zenith combo so good? I don't know how the RCA compares, but I'll do a quality comparison with the donor I picked up before pulling the trigger on swapping.

I read somewhere that the RCA A63ADT10X05 that I have was a TV tube, but after looking into it further it looks like they show up in arcade cabinets somewhat often. I don't know where the RCA tube came from; all I know is that some previous owner made some modifications to the monitor mounting points on the cabinet. So maybe it was original, maybe it was a swap from another cabinet, maybe it was a swap from a TV. I have no idea at this point!

 

[Mukuro_W]

RCA tube + K7400 was the last 15khz monitor series with was released by Wells Gardner, it was the successor of the legendary K7000 by the way I do not know if it deserve the same awesome picture quality.

 

[Srayer]

I spent some time last night trying to get the Sanyo DS25320 tube fired up on the K7400 chassis.

Here's the label.

Here's what it looks like with the back removed, and safely discharged with the pictured HV44A high voltage probe.

The tube model is A63QDB891X. This one is unbranded a Samsung (thanks trashedcabs), but I've also seen them online branded as Panasonic, or Sharp.

Horizontal resistance is 1.5 Ohms, and vertical is 6.2 Ohms. This is really close to the RCA tube that came in the cabinet, which is 1.8 Ohms horizontal and 5.6 Ohms vertical. This looks very promising!

After some slicing and dicing the connectors and crimping on some 0.093 molex pins, I removed the original chassis and neck board, and attached the K7400. I then connected the PSU, isolation transformer, and JAMMA harness that I stripped from the cabinet. Time to fire her up. Fingers crossed!

Look at that! It's upside down, and it's intermittently flickering green, but we have a picture!

Here it is after I flipped the horizontal and vertical wire pairs to fix the orientation, and did some quick adjustments to stop the flickering. Not bad!

And here it is running more appropriate content.

All right! This is definitely a viable donor tube. This is looking decent and is free from burn in, but I'll do some quality test of this vs. the RCA tube this weekend.

 

[PASTBLASTER]

Awesome job so far! This is making me want to get off my ass and restore mine! Keep it up!

 

[Mirkvid]

Great thread, looking forward to seeing the final product!

 

[XtraSmiley]

Great job, looking forward to following your progress!

 

[Srayer]

I worked on the WG K7400 chassis last night.

Here's the star of the show. I've been eyeballing one of these desoldering tools for ages, and finally sprung for one knowing I was going to recap my chassis. Now I wish I had bought it years ago; it's like magic how well it works. I wasted so much of my life with solder suckers and desoldering braid!

Here's the final result. I initially recapped everything and then tested the chassis out on my Sanyo donor tube. The picture was good, but I was still getting intermittent flashes of white, and would get the same whenever I touched the dials on the flyback. So, I replaced the flyback, which resolved all of those issues. I also checked B+, which was a little high at 121v. I dialed it back to 117v as per spec.

The picture is great now! I still need to tweak the colors a little, but it's much brighter and more vibrant than before. This is going to look great in the cabinet.

I got both the cap kit and flyback from arcadepartsandrepair.com:
https://www.arcadepartsandrepair.co...dner-k7400-k7500-series-monitor-cap-kit-105c/
https://www.arcadepartsandrepair.co.../270uf-400v-nichicon-105c-b-filter-capacitor/
https://www.arcadepartsandrepair.co...3x0671-001-wells-gardner-k7400-k7500-flyback/

 

[trashedcabs]

The tube model is A63QDB891X. This one is unbranded, but I've seen them online branded as Panasonic, Samsung, or Sharp.

SDI in the corner means Samsung SDI, their materials and components division.

Nice cab, looks like a fun project!

 

[Srayer]

I only had one day this weekend to work on the cabinet, so I focused on woodworking. I sanded down the wood filler on the sides, but most of my time was spend on the back panels. The first thing I did was take measurements of each panel, which I will post here once I've verified all the new panels I cut fit together properly.

The main task at hand was removing the existing water damaged panels. The panels were glued and stapled down, but with some applied science (a scraper and hammer)...

...the first one came off fairly easily. There was still glue and wood residue on the cabinet structure that I would have to scrape off later.

The top panel was a little tougher. I had to remove all the staples before hammering the scraper underneath, because they were blocking its path. Fortunately, since the wood was rotted, I was able to use a flathead screwdriver to pry them out a little, and then use a pair of pliers to remove them completely.

The panel was glued down really well, so it was a lot harder to get off. But I got there.

...but not without some collateral damage to the side panel. I'll have to fill that with wood epoxy later.

The rest of the panels came off without incident. After getting all the panels off, I spent a good hour and a half scraping all the glue and wood residue off. I tried using a heat gun to soften the glue, but that just made it stickier and harder to remove. So I just went at it with brute force.

The bottom part was the worst. The staples here were shot in from the inside, unlike the rest of the cabinet which was from the outside. So, they didn't come off with the bottom panel, and I had to remove them manually. Some I was able to pound out with a hammer and then pull out with pliers; others I had to pry out with a screwdriver from the inside, which caused more damage than the hammer method.

Here are all the old panels. You can see how rotted they are, and how bowed and warped the top panel is. I'll use the fan and monitor panels as templates to cut those inner shapes; the rest go straight into the trash. Bye!

I started cutting the replacement pieces, but didn't finish. I also did a painting test run on one of the pieces. This is 3 light coats of spray primer, applied a few minutes apart, then left to dry for 30 minutes. After that, I applied 3 light coats of semi-gloss black spray and let it dry. You can see some wood texture, which is fine for the back. Maybe it's a little too glossy? I don't really know what it's supposed to look like since mine was so thoroughly rotted.

And that's about it for the work. I did find a previously unnoticed problem, though: the inside edges of the side panels are in bad shape. Those edges are going to be visible, so I'll have to do some repair. These currently have the same black overlay that the outside used to have. Replacing the overlay would be difficult, because of all the wooden supports stapled to the side of the cabinet, as shown in the above picture. Cutting a replacement overlay to go around these would be next to impossible, and I really don't want to remove and reattach them all. So I think I'll strategically cut the overlay around the supports, repair the wood, and paint it black.

But, that's a problem for next weekend!

 

[bananaman1525]

Looking good! Are those joysticks the original type or happ style ones?

 

[Srayer]

I didn't look very closely, but most likely Happ. I'll take a look later when I'm home.

EDIT: They're Happ-style, specifically newer IL sticks.

 

[Srayer]

I'm going to start splitting these posts up by day instead of by weekend, just to make it easier to manage for me. So, here's what I did on Saturday.

I started working on stripping the inside of the panels. The plan was to strip the inside-front area, first by cutting the overlay around the supports with a box knife then stripping it with a heatgun and various scraping tools. The overlay was really difficult to remove, much moreso than the outside overlays. I eventually figured out a method of using my heatgun on high to get the overlay really hot, then peel from there. I eventually got a groove going, but it took around 45 minutes per side.

After stripping the inside-front, I took a closer look at the remaining inside edges and saw that they were peeling and swollen, as well. These will just peek out once I replace all the back panels, and I really didn't feel like stripping everything after my experience with the front.

But, in for a penny, in for a pound. If I'm going to refurb this thing, I might as well do it right. After stripping everything, I filled in all the damage I could find with Bondo. I had an easier time with the Bondo this time than I did originally; I think I used too much of the hardener the first time, and I started to get a better feel of the working time before it hardened. I forgot to take a picture of all that, though. Also not pictured: I finished cutting the back panels.

I then started priming some of the back panels.

 

[Srayer]

On Sunday, I worked on the scariest part: cutting off the bottom edges of the cab and replacing them with new particle board. I was worried that my cuts might be inaccurate enough that the pieces wouldn't join well, and that the old wood might be swollen enough to not join well, and just generally worried about screwing up.

The first order of business was to lay the cabinet down and figure out how much to cut off. I decided to cut off 7", for no particular reason other than the replacement boards I had were around that size, and might as well get as much new good wood in there as possible, right? So, I measured, and checked, and measured, and checked, and set up the cutting guide, and measured, and checked. And before cutting, I measured and checked one more time.

All the double-checking paid off; I got a nice, clean, straight cut. There was a lot of glue and particle board remnants left after prying off the old wood, so I got down to scraping.

With some elbow grease and plenty of sweat, I got it scraped pretty clean.

After another bout of repeated measuring and checking, I got a new board cut that fit perfectly! I didn't get a picture when I was cutting, but my setup here is a couple of sawhorses, a circular saw with a fine-toothed blade, a measuring tape, and the cutting guide with c-clamps as pictured above.

I got everything set up to fix the new board in place, but then realized my pneumatic nailer doesn't accept staples. So I glued the board in place, both on the face and on the edge, screwed it in on the bottom as before, and tacked it in place on the top with a narrow piece of plywood that I had on hand. I don't love this, so I'll replace it later with a piece of particle board and use either staples or wood screws to fasten everything.

After that, I repeated the same thing on the other side. That was pretty uneventful except that my initial cut to the cabinet was a bit askew, since due to damage I didn't have any good reference points on any of the existing panel edges to mark a straight line. I was able to correct it with another strategic cut, though.

So, that's what it looks like on both sides. After I get the new panels stapled in place, I'll get some Bondo on the seam.

 

[DelsArcade]

Great restoration with attention to detail! I have a 4 slot cabinet myself in storage that's in fantastic shape. I'm pretty sure I will need to replace the marquee panels, etc. I'm curious to what your solution will be.

Del

 

[erdrick1980]

Love it. This thing is going to look bad ass. Never seen someone remove panels before. Makes me want to do same to my dual slot mvs cab since it needs it too, one day. Lol