Best way to sand bondo'd corners?

thefader

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I'm rebuilding another Nintendo cabinet. On this one, the inner half of one of the sides (where the molding attaches in) was broken. I put bondo here, to rebuild this part, and saw in a new notch so the molding can fit back. Naturally, some bondo got on both where the black lip will be, and the blue front panel. How the hell do I sand this to a nice 90 degree angle?
 
If you've already applied bondo to the corner, just use a power sander or sanding block and do each side of the corner one at a time making sure to keep flat. Work your way outward and upward as to not accidentally chip or crack the corner.

Here's some pics. I know I made a mess with the bondo, but it turned out fine. :D

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Here is the area, I know it will look better than it did originally, but I'm not sure the best way to get it to look the best.
 

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I see. I would just sand down the front where the slot is first then work your way to the side and inside. A power sander would chew up the front panel, so I would recommend using a sanding block (the kind that is foam that has sanding material on all sides) and just sand it that way. It will take a lot of time with the amount of bondo you have there, but with any restoration, the more time you put into it, the better the pay off in the end.
 
For that one, prep woulda been key. Either build a plexi mold for the inside corner, or use masking tape on the kickplate, built in layers at least an inch wider than the bondo spreader you are using. Now you need to use a chisel and a low grit sanding block.
 
For that one, prep woulda been key. Either build a plexi mold for the inside corner, or use masking tape on the kickplate, built in layers at least an inch wider than the bondo spreader you are using. Now you need to use a chisel and a low grit sanding block.

That's another good point. For future projects, just know that more bondo means more sanding. It's better to mask off where you don't want bondo (or paint) and create a mold where you want the bondo to flow. Makes your job a lot easier.
 
I was kinda thinking that, but It turns out this was harder than I thought It was going to be.. I guess my plan now is to sand the side with the notch down with my orbital sander, and sand the side down with a block like you said..


Would you prime the front panel and the black lip, then paint the lip black first, then do all of the blue work?
 
I was kinda thinking that, but It turns out this was harder than I thought It was going to be.. I guess my plan now is to sand the side with the notch down with my orbital sander, and sand the side down with a block like you said..


Would you prime the front panel and the black lip, then paint the lip black first, then do all of the blue work?

Well, if it was me, I would sand and repaint the whole cab at this point. Unless you have an exact color match that will blend in nicely which is not likely.

Either way is fine. I usually mask off the front and then paint the black, then mask off the black when it's time to paint the front. Or you can go crazy Gregatron style and just take the whole thing apart, sand and paint, and reassemble. But not everyone is that hardcore.
 
Oh, that was in the plan from the beginning. I will sand prime and paint the whole thing anyway. I just need advice on getting it all squared up and straight.
 
For shaping corners and curves, I use a Black and Decker Mouse finishing sander. Works great and makes short work of even fairly thick globs of Bondo.

For the t-molding channel, use a slot cutting bit on a laminate trimmer or router.
 
sanding bondo

all bondo is formed with a rasp and the final sanding must be done with sandpaper. clamp a block along one side of the part you are sanding to use as a guide for the sanding block this will help keep the corners square. the sanding block must not have custion or foam blocks they will round your edges. the perfect thing if you can find it is to take a very thick piece of glass (like 1/2" thick and square to fit the size of your hand) then put a self adhesive sanding pad on it and you will have a perfectly flat and hard surface for sanding with. they use glass as a backer for many high end finishing/sharpening tools because its perfectly flat and doesn't flex. if you can't find any glass use whatever else that you can find that works on the same principle.
thanks
 
Didnt realize it, but this cab has more damage than i thought. the board that is right above the coin door is broken.. Any fix it ideas?
 
The 1.5" thick part of the front of the cabinet, above the coin door, is broken. What is the best way to fix this? Would drilling a brace board on the inside on each side of the break work? Then Bondo over the crack and prime and paint?
 
Just pull the kick plate off and use a block to sand it.
Nintys come apart so easily.
 
And don't use a rasp...too easy to gouge your wood. For big chunks, drill some screws into the area to give the bondo something to grab on to and just build it up. Tape pieces of plastic as a form to help guide your placement and support it while it sets up. There are TONS of pics out there in the restoration section that show this, I know I've got a pic of it in my 720 and/or Discs of Tron thread.
 
Fader is the broken piece the one under the speaker panel or the kick panel itself?
If it is the underside of the speaker panel then you could just remove the whole speaker panel assembly and replace the broken piece.
Pics would really help.
 
I was wondering the same stuff too, happy I found this thread. I just stripped my cab down and there are two parts that need repair. Both sides have ripped up bottoms. The cab didnt have any legs so it sat directly on the wood.

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and the top looks like it was made of MDF, where the rest is plywood. The cab in almost 30 years old and the top is all screwed up.

3-top.jpg


I plan on putting Bondo on the bottom and putting aluminum foil and a piece of wood on either side to keep the sides from getting screwed up and then letting it harden and working it down, what do you think?

Also, what can I do about the top piece?

Thanks.
 
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