Making my own backplates- ATi 3870's

Hey there everyone! Recently I've purchased four ATi 3870's to mess around with and quadfire in a server/gaming build I plan on doing. Unfortunately, the bright red cards don't remotely match the blue/purple color scheme I was planning on doing. Therefore, I needed backplates. There are EK waterblocks installed on them, but EK never made a backplate for the card, so I had to figure out something.

With my extremely low skill in metalworking, I went to Lowe's and picked up a piece of 12x18 sheet metal. I want to say I purchased 20ga, but I don't know for sure. If someone would like an exact measurement, I'd be happy to get my calipers out. Anyways, like I said, I have four 3870's, so I had to cut out multiple pieces. The card itself is about 3.85" x 9", but I cut out pieces that were 4.875" x 9" (more on this later). I used a jigsaw with a 24TPI bi-metal blade to cut the metal.



After cutting, I got the raw backplate cutouts. Not too shabby!



Well, I could do sanding and drill my holes, but I couldn't just stop at a simply backplate. I wanted to make an overhang that would cover up the right side of the card. I'll most likely paint a logo of some sort on it, but it's primary function is to cover up as much of the red as possible.



Remember that extra 1" I left on the blanks? That's going to be used for the overhang. After sanding the rough edges down, I used the jigsaw once again to cut out a chunk of metal from the blank to accommodate the waterblock and CrossFire bridges.



Now comes the most nerve racking part of the fabrication, bending the overhang. It's not hard to screw this up, so I did a couple practice runs on scrap metal to get the general "technique" down. So, I got out the blowtorch, and after clamping the backplate blank in a vice, I heated the bend area to soften the area up.





During my practice bends, I noticed that simply bending the metal over the side of the vice doesn't leave a perfect 90 degree angle. In fact, it's an extremely wide bend. After hand bending the metal over the vice, I took a hammer and smashed the metal into a near perfect 90 degree angle. I know it's a relatively crude way of doing so, but it actually worked really well. I apologize for the very blurry image, I don't relaly know why it turned out that way, but you get the jist of what I was doing (hopefully!).




The next step is going to be a nice sanding to work out all the dents, as well as re-firing a couple places to straighten them up. Afterwards, it'll be a coat of paint and some accent pieces. Finally I'll have to drill holes for the backplates too so it can actually go on the card! No work tomorrow, so I'll definitely be working on these after shooting in the morning! Let me know what you guys think so far. Anything I can refine on? Any ideas on how to make them better?

Thanks

EDIT (for easy access):

PART 2

PART 3
Edited by WebsterXC - 7/28/12 at 2:03pm

Alright well today after shooting I got right back to work! I really wanted to paint these backplates today so I had a lot of sanding to do. The first priority was exposing the dents and blemishes where I hammered yesterday. While I can see them clearly, a light sanding will expose them even more. I used a simply 220 grit sandpaper to do this. I really didn't spend too long on each card, I only needed to mildly scratch the surface.



Here's a picture of essentially what I was trying to do. Before on the left, after on the right. The glare makes it difficult to see, but I couldn't find a place where that wasn't happening. I need a better camera...



Next it was time to unload the big guns. I needed to get those dents out of there. Not only that, some areas were not flat and many edges were not straight. So, I got out my trusty belt sander, installed a new roll of 120 grit sandpaper and let her rip!



The belt sanding portion was probably the most time consuming. You have to be extremely careful at this step because although you are working with metal, the 120 grit sandpaper can still eat through edges and corners and leave you with awkward bevels. Not only that, the friction heats up the metal extremely quick, causing it to become more malleable. If you're not gentle, you can bend the backplate on accident. It happened to me slightly on one plate and it too me awhile to straighten it back. The result though, was an extremely smooth top portion with most of the dents removed. There were still some areas that needed work, but I'll have to leave that to hand sanding.



Next comes the hand sanding. OH BOY! No, really, it's extremely tiring and also takes a long time. I bumped up to a 320 grit sandpaper once more and sanded the top of the backplate extremely vigorously, focusing on the areas where I bashed the metal. Even more dents were worked out. Many people would choose to continue with 320 grit or continue with 600 and 800 grit sandpapers for a perfect polish. Because I'm painting these, and the four backplates sit pretty close to each other, I decided to stop here; the remaining dents will be virtually unnoticeable.



Now I needed a way to actually attach the backplates too the cards themselves. I got one of my 3870's and a folder that I cut up and traced the card. Then I took a sharpie and put dots through all the available holes that could accept screws through them. It's not very fancy, but it sure beats the heck out of measuring and transferring!




After cutting out the outline, I taped it onto the backside of one of the backplates and used a drill press on all of the little dots I made for the screwholes. I simply used the same pattern for the other three cards.




Ta da! Screwholes for all the backplates




After thoroughly washing the backplates, it was time to paint them. First one coat of primer:



Then one coat of black. I ran out of paint, so I'll have to stop here for today. Tomorrow I'll try to pick up some more paint and mounting hardware after work and hope I have time to continue on these.


Edited by WebsterXC - 7/22/12 at 6:00pm

Thanks guys! I was kinda disappointed I ran out of paint, I was eager to finish them.

It's making me think though. I don't know if I like the satin for sure. My EK blocks are acetal, so I may pick up a flat black at Wal-Mart tomorrow instead.

Or maybe some kind of sparkle crap? What would look good?

Yup this^

It's solely for aesthetics. I wanted to try to cover up as much of the red PCB as possible since the build these are going into is blue and green. I'll probably paint some kind of logo or something on the hangover piece since I don't have a CNC to help me carve straight.