There are a number of advantages to using glass as the build plate on a 3D Printer. Not having to worry about retaping and not having to buy expensive wide rolls of tape (or worry about tape lines on your print) are why I choose to use glass, or more recently FR-4, on my build platforms.
A major downside of using glass or FR-4, however, is the loss of build space that can result from having the build plate secured with the traditional binder clips. It is never a good thing to hear the noise your printer makes when the nozzle catches on one of those damn clips!
This instructable presents a way of securing glass or FR-4 without using a binder clip there-by preserving as much build space as possible...and...avoiding having a nozzle drag across a binder clip!
Step 1: Find Some Clips to Cut Down
I was not sure what I was looking for but after spending a while with Google I was able to find some beam edge wiring clips that looked like would do the trick. The ones that I found were: "Newlec Edge Beam Clip. For 8mm - 12mm Grip, 10mm - 11mm diameter". They come in a variety of sizes but the 8-12mm grip, 10-11mm diameter, matched what I needed for either glass or the thinner FR-4. I am not sure if these clips are available internationally but with the image in hand you can likely get Google to search for something similar.
Next step was to put a metal cutting wheel on my Dremel and cut the clip leaving the grip side in the bin and keeping the rest for use on my printer. What I llked about the shape that I am left with is that flat top.
Step 2: Print Some Inserts
Next you want to print the inserts that match what kind of build plate you are going to use. There are two choices that can be downloaded from Thingiverse, one for glass, and one for FR-4. Once printed the insert can be, yes, inserted into the clip you cut down in the last step.
The download from Thingiverse includes the Sketchup file as the size needed for your build platform could be different from mine (Wanhao Duplicator 4S, a Makerbot Clone).
The inserts go into the metal clip with the rounded side of the insert matching the rounded side of the clip. On glass they serve two purposes. First, they constrain the clip from sliding more than what is needed for holding onto the build platform thereby protecting the space available for printing. Second, they provide a bit more of a handle than the clip itself would.
On FR-4 they play one more crucial role and that is all about the little tab. That little tab makes up for the thickness difference between FR-4 and glass. There is a smaller clip size available but I did not want to buy another box.
Step 3: Mount Them on Your Printer
They should be reasonably tight yet still reasonably easy to slide onto the build platform.
Step 4: Put the Binder Clips Away
The benefit is two fold. First that less room is taken from the build area. Second, and much more critically, the vertical clearance is very, very much lower!
There is one small rub. I run the first layers of my ABS with the heated bed at 110c. Over time this causes the inserts to warp and could cause the FR-4 or glass to become loose...with not so pretty results to prints! As I mentioned before there is a smaller clip size that I really should use. I am going to order some but in the meantime I had some of the inserts printed in resin.
I used Lumico Design's Hub, a 3D Hubs printer, and have them on the printer now (picture above). No rational person would have done this given that buying the smaller clip would be cheaper but I really wanted to try the resin printed part! They are working as expected the question will be how they handle constant temperatures of 90-100c.