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Loading ...Polishing
syrillian
Hello again.
I needed to attend to 2 more cuts before I went to the polishing.
Lately when I have been building and modding I have been using slot-loading optical drives. I have but one left, and it is for my current personal project… selfishness is not gentlemanly, but it is core to the case design. The slot-loading drives make for a very clean face (please excuse the “noisy” shots):
TJ07
Custom Case (Halcyon).
But, for this project I have a tray-loading drive.
I still want to keep the face of the case as visually clean as possible, so I have removed the bezel on the tray itself so that the cut out can be made smaller. I’m not sure how I will finish the bare tray, but I will cross that bridge when I get there.
In this instance I used a flush rout bit to cut out the rectangular hole for the optical drive tray.
This part can be tricky when making custom cases. The alignment (vertical and horizontal) needs to be essentially perfect so that the tray slides in and out freely and cleanly; allowing some leeway for error may be in order. Note that the last portion of the previous statement really only applies if one is working without plans. If a full technical drawing or a CAD rendering (complete with dimensions and measurements) is done then this portion of the build is not as difficult.
The Optical drive will sit on a platform or perhaps be mounted to acrylic panels in the traditional manner. Most likely it will be via the traditional manner as I can cut vertical slots in the panels so that I am able to adjust the height that the optical drive sits at, and horizontal adjustment can be done with the panels (but that is later on).
I used the fence guide to make the appropriate cuts. I drilled the pilot hole then placed the panel to be cut on the router bit. Then I squared up the panels using an angle. Once I had the all the parts lined up properly I clamped the fence guide to the routers table top and proceeded to make the initial cut making sure to stop just within the line that I used to mark the perimeter of the cut.
The cut-out required was too tall to be made with 2 passes of the router, so I needed to make 2 very short cuts on the short sides. The same technique mentioned above and shown below was used for all 4-sides. I did need to adjust and re-align the panel for each cut. An easier way would be to use a box-guide.
The power switch also needs a hole. Generally I use the same diameter and type of power switch (different models, same dimension). The cut out needs to be ¾” in diameter, and although the rotary tool is quite capable of making this hole I favor the forstner bit.
Matthew Black has already issued the appropriate warning about the nature of these bits. It is akin to grouse-hunting with a bazooka. Even in the face of such overkill I still use the bit as it makes a clean hole that is much easier to manage than the rotary tool. Small diameters can be difficult with holes that can not be seen as they are being cut. This is the case with such a small hole; the tool and the guide completely block the line of sight. One can over-come this by cutting from the underside, but my experience is that holding the rotary tool upside-down whilst cutting means one more action/movement that must be monitored. I used to do it this way until I was able to purchase the appropriate forstner bit.
That thing even looks mean… doesn’t it?
It is prudent to note that the initial drilling needs to be done a little slower and with less pressure. Once the bit is shaving material off and has sunk in about 2mm then the rpm of the drill can be raised; one reason to go slowly is that the bit will have an inclination to travel until seated within the hole it is cutting.
Polishing
Once all the cuts have been made and all the profiling is done it is time to attend to the finer details.
For the most part 400 and 600 grit sandpapers are sufficient to get a nice smooth, satin finish. Occasionally I have needed to use 240 grit sandpaper to remove particularly deep clefts or bit-marks (deep being .5mm).
For small detail work and to square round cuts that were made by the router bit I use a set of small files. I also use some home-made “sanding blocks” as well as the real deal. For contours that I wish to remain round I use the round file.
And, although not used in this project, larger panel edges can be sanded using an orbital sander to expedite the process. Note that after using this tool a quick hand-sanding will be required so that all grooves in the panels edge from the sanding are running the long axis, and not swirled or circular as those types of marks do not polish out readily or as well as the previously mentioned direction. The orbital sander is generally used only when more aggressive sanding is in order.
To finish off the polishing procedure I use a drill with a muslin wheel attachment, or a rotary tool with a similar but much smaller attachment. The block in the middle is rouge, a polishing compound that is applied to the buffing wheel.
The image of the fan hole below shows that results of a round-over router bit prior to sanding.
And here is a straight edge that has been sanded to a finish that is ready to be polished. Before polishing the fan holes, they were also sanded to a similar finish.
When polishing I travel back and forth across the edge at a leisurely pace. I also switch sides, meaning the buffing wheel rotates in both directions along the edge. Generally the last pass will be in the same direction as the rotation of the buffing wheel as this leaves the cleanest finish. The same technique is used when polishing the inside rim of fan holes. It is also advidable to run the buffing wheel perpendicular to the edge so that the roundover termination point is thoroughly polished. If an area is not as clean as the rest it can always be touched up later.
When polishing flat edges care should be taken when reaching the corner of the panel, the buffing wheel can “bite” into the corner and kick outward. In the image below, the wheel is spinning in a clockwise direction so the corner that would catch would be the one on the right; were the wheel to be spinning counterclockwise, the corner to watch would be the one on the left.
Here are some shots of the polished edges.
The final polish is done with a micro-fiber cloth and a cleaner specifically for plastic and anti-static.
Next up: Capillary bonding.
Thank you for stopping by.
:)
where did you get the slot drives from? I have been looking for ages.
They are Plextor drives, and can be very hard to come by. I purchased them online from CyberDruidPC.com, and I was also able to find them on ebay.
From what I have been told, these drives are no longer made; because of that, and their scarcity they can cost a pretty penny.
have you tried flame polishing at all
Greetings, Mickc22.
Yes, I used the technique for awhile on clear extruded acrylic but moved to sanding and polishing with a muslin pad. I did so as I only have a small butane torch, and I think that a better tool would be required for better results.