Cutting the Board - Revision history

Aplstudent at 22:43, 2 March 2019

2019-03-02T22:43:47Z

Aplstudent at 22:02, 2 March 2019

2019-03-02T22:02:57Z

Aplstudent at 21:44, 2 March 2019

2019-03-02T21:44:23Z

Aplstudent at 21:21, 2 March 2019

2019-03-02T21:21:14Z

Aplstudent at 21:05, 15 February 2019

2019-02-15T21:05:09Z

Aplstudent at 21:20, 6 February 2019

2019-02-06T21:20:56Z

Aplstudent: Created page with "Measure the dimensions of the printed transparency, and mark these off on the physical undeveloped PCB. With a heavy duty cardstock cutter line up the PCB such that the usabl..."

2019-02-04T22:58:20Z

Created page with "Measure the dimensions of the printed transparency, and mark these off on the physical undeveloped PCB. With a heavy duty cardstock cutter line up the PCB such that the usabl..."

New page

Measure the dimensions of the printed transparency, and mark these off on the physical undeveloped PCB. With a heavy duty cardstock cutter line up the PCB such that the usable portion hangs to the left of the blade. This will minimize splintering of the board when it is being cut. When ready to cut, slice the board with force in one continuous motion. With a cut PCB, slightly larger than the transparency, you are now ready to develop the board.

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-Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board. If the board does not lie flat against the film print then the exposure will be fuzzy and the image transfer will lack the high resolution necessary.
+If the board is not roughly the shape of your lithographic film PCB then you'll need to cut the board. The fiberglass layer of a PCB can be extremely hard on tools and create dangerous silica dust when cut, thus cutting the board requires strong tools, a dusk mask and good ventilation. There are several ways to cut the board but using a diamond blade saw yields the cleanest cut with the most precision. Using a hacksaw is another method but the cuts will not be as straight and ventilation will not be ideal if this is done in the APL. It is also possible to cut PCBs with paper shear but this results in warped edges that will prevent your board from lying flat in the UV chamber (which is essential for the image transfer process from the lithographic film).
-Before cutting the board, mark the white protective tape using a pen and straight-edge, then clamp the board in the yellow rubbery gentle-jaws in the vise and saw horizontally.
+This makes using a diamond blade saw your best option. While there is a small diamond blade saw in the APL, I strongly recommend using the one in the craft center's Glass Shop (which is free for students to use). The glass shop is very well ventilated (make sure the fume hood in the room is turned on) and the saw blade has a source of running water that flows over the blade as it cuts, this is ideal for cutting glass/fiberglass because the water traps silica dust during the cut. Lastly, the saw in the craft center has a sliding bed for you to rest your PCB on, which will ensure a straight cut. Below is a labeled picture of the diamond blade saw I recommend you use:
-Once the board is cut to size, the artwork is ready in the UV chamber (READ AHEAD!), and all that remains is to slip the copper board between the films, peel the protective layer off. If the board was cut, the edges will have sharp copper sticking off them. Not only will this prevent the film from lying conformally flat against the board, it will also scratch the emulsion with devastating efficiency: If the board has been cut, after peeling the white protective film off, both sides of every cut and all four corners (even of a single-side board) MUST be turned down with a file.
+[[File:Diamond Saw.png]]
+Now, if your PCB is new take your PCB out of the metallic bag. The PCB will have two layers of thin white plastic adhered to both sides, this is to protect the photoresist from UV light and scratches. Do not remove this layer until you are ready to expose the board in the UV curing chamber. Next, mark your PCB with a straight edge and maker to indicate your cut lines and then make your way to the saw. Although the glass tech should make sure the water is running over the saw blade before you make your cut, this step can be forgotten, so be sure to double check that water is dripping off of the saw blade before you use it. Cut your PCB and head back to the APL with the boards protected from UV light. Lastly, you'll want to carefully turn down down any cut edges. The copper will likely be bent along the edges from cutting the board so you must use a file to make these edges smooth. Your board is properly filed when both sides lay flat against a flat surface. Flat boards are necessary to ensure that the lithographic film lies flat on the board, if the film does not the image will lost resolution and make the the image on the board fuzzy.

← Older revision		Revision as of 22:02, 2 March 2019
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	This makes using a diamond blade saw your best option. While there is a small diamond blade saw in the APL, I strongly recommend using the one in the craft center's Glass Shop (which is free for students to use). The glass shop is very well ventilated (make sure the fume hood in the room is turned on) and the saw blade has a source of running water that flows over the blade as it cuts, this is ideal for cutting glass/fiberglass because the water traps silica dust during the cut. Lastly, the saw in the craft center has a sliding bed for you to rest your PCB on, which will ensure a straight cut. Below is a labeled picture of the diamond blade saw I recommend you use:		This makes using a diamond blade saw your best option. While there is a small diamond blade saw in the APL, I strongly recommend using the one in the craft center's Glass Shop (which is free for students to use). The glass shop is very well ventilated (make sure the fume hood in the room is turned on) and the saw blade has a source of running water that flows over the blade as it cuts, this is ideal for cutting glass/fiberglass because the water traps silica dust during the cut. Lastly, the saw in the craft center has a sliding bed for you to rest your PCB on, which will ensure a straight cut. Below is a labeled picture of the diamond blade saw I recommend you use:

−	[[File:]]	+	[[File:Diamond Saw.png]]

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 Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board. If the board does not lie flat against the film print then the exposure will be fuzzy and the image transfer will lack the high resolution necessary.
 Before cutting the board, mark the white protective tape using a pen and straight-edge, then clamp the board in the yellow rubbery gentle-jaws in the vise and saw horizontally.
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 This should be done with the local fluorescent lights off and the incandescents on, to minimize unnecessary exposure of the photoresist to stray UV. The deburring is complete when a fingernail (which is placed DELICATELY - you can very easily scratch the green photoresist off) glides off the edge of the board with no resistance or 'catch' at the edge.

← Older revision		Revision as of 21:21, 2 March 2019
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	Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board. If the board does not lie flat against the film print then the exposure will be fuzzy and the image transfer will lack the high resolution necessary.		Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board. If the board does not lie flat against the film print then the exposure will be fuzzy and the image transfer will lack the high resolution necessary.
		+
		+	== Hacksaw Method ==

	Before cutting the board, mark the white protective tape using a pen and straight-edge, then clamp the board in the yellow rubbery gentle-jaws in the vise and saw horizontally.		Before cutting the board, mark the white protective tape using a pen and straight-edge, then clamp the board in the yellow rubbery gentle-jaws in the vise and saw horizontally.

@@ Line 1: / Line 1: @@
-Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board.
+Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board. If the board does not lie flat against the film print then the exposure will be fuzzy and the image transfer will lack the high resolution necessary.
-This will make the boundary between 'exposed' and 'not exposed' fuzzy and destroy the resolution of the transferred image.
+Before cutting the board, mark the white protective tape using a pen and straight-edge, then clamp the board in the yellow rubbery gentle-jaws in the vise and saw horizontally.
 Once the board is cut to size, the artwork is ready in the UV chamber (READ AHEAD!), and all that remains is to slip the copper board between the films, peel the protective layer off. If the board was cut, the edges will have sharp copper sticking off them. Not only will this prevent the film from lying conformally flat against the board, it will also scratch the emulsion with devastating efficiency: If the board has been cut, after peeling the white protective film off, both sides of every cut and all four corners (even of a single-side board) MUST be turned down with a file.
 This should be done with the local fluorescent lights off and the incandescents on, to minimize unnecessary exposure of the photoresist to stray UV. The deburring is complete when a fingernail (which is placed DELICATELY - you can very easily scratch the green photoresist off) glides off the edge of the board with no resistance or 'catch' at the edge.

← Older revision		Revision as of 21:20, 6 February 2019
Line 1:		Line 1:
−	~~Measure the dimensions of the printed transparency~~, ~~and mark these off on~~ the ~~physical undeveloped PCB~~. ~~With~~ a ~~heavy duty cardstock cutter line up~~ the ~~PCB such that~~ the ~~usable portion hangs~~ to the ~~left of~~ the ~~blade~~. This will ~~minimize splintering~~ of the board ~~when it~~ is ~~being~~ cut~~. When~~ ready to cut, ~~slice~~ the board with ~~force in one continuous motion. With a~~ cut ~~PCB~~, ~~slightly larger than~~ the ~~transparency~~, you ~~are now ready to develop~~ the board.	+	Our blank boards are 4x6 or 6x6 inches; There may be smaller pieces that can be used as well. If you need to cut a board, use the hacksaw. NEVER use the paper shear - It will not only cut uncleanly (destroying a half cm wide region on both sides of the blade), more importantly it will permanently warp the board and make it nearly impossible to get a uniform close contact between the artwork film and the board.
		+
		+	This will make the boundary between 'exposed' and 'not exposed' fuzzy and destroy the resolution of the transferred image.
		+
		+	Mark the white protective tape using a pen and straight-edge, then clamp the board in the yellow rubbery gentle-jaws in the vise and saw horizontally.
		+
		+	Once the board is cut to size, the artwork is ready in the UV chamber (READ AHEAD!), and all that remains is to slip the copper board between the films, peel the protective layer off. If the board was cut, the edges will have sharp copper sticking off them. Not only will this prevent the film from lying conformally flat against the board, it will also scratch the emulsion with devastating efficiency: If the board has been cut, after peeling the white protective film off, both sides of every cut and all four corners (even of a single-side board) MUST be turned down with a file.
		+
		+	This should be done with the local fluorescent lights off and the incandescents on, to minimize unnecessary exposure of the photoresist to stray UV. The deburring is complete when a fingernail (which is placed DELICATELY - you can very easily scratch the green photoresist off) glides off the edge of the board with no resistance or 'catch' at the edge.