Clamps / clips for glass on heatbed

Question

I'm looking for clamps to fix the glass on my heatbed. After some search I found that some people use clamps printed of PLA. Can I use PLA clamps for a heated heatbed (~60 °C)?

I also tried foldback clips but they block my nozzle. The Anet A8 starts in the front left corner. When I start to print, the nozzle moves a little bit up on z, then up on y and right on x. At this first move it moves into the fold back clip. I'm looking for a way to fix the corners and not to fix the edge in the middle.

What other clamps or clips can I use to fix the glass (~3 mm) on the heatbed (~2.5 mm)? I don't want to use glue.

My printer is an Anet A8.

Answer 1

How about the Ultimaker clips? Ultimaker uses 2 mm heat bed and 4 mm glass, that should be within reach by bending the clips a bit. They have quite a low profile/footprint.

These clamps are very cheap and can be found on those typical auction or Chinese sites.

Alternatively, you can also tape the glass to the aluminium bed using kapton tape if you are concerned about hitting the binder clips.

Note that e.g. in Marlin firmware, you can define a Z-offset to prevent hitting the binder clips on movement.

Answer 2

There are some clips similar to Trish's answer that aren't mounted but have a spring in them to apply pressure. Looks like they are called Swiss clips: Glass retaining clips – Swiss made:

Answer 3

PLA has two problems that keep it from being usable for your purposes.

First, it deforms under load. I've used printed C-clamps for various jobs; by the time I'm done, the clamp is generally warped by 10+ millimeters.

Second, PLA has a very low heat tolerance. The glass transition temperature of PLA is around 60-65°C, right around your intended heatbed temperature, so not only will your clamps deform from the load, the plastic will flow from the heat.

If you were printing on a cold bed, you might be able to use printed clamps, printing out a fresh set whenever deformation of the current set gets too high. On a heated bed, not a chance. Look for some sort of metal spring-based clips instead.

Answer 4

Let's analyze the problem:

• We have a 5.5 mm total thickness.
• We want to (semi)permanently affix the two layers together mechanically.
• The clips shall not be higher than about 0.2 mm to allow the nozzle to pass over them.

(non)Solution attempt zero:

Let's look at the problem objectively... we can print something, can we? Well... 0.2 mm or below of PLA means 0.2mm of PLA that need to withstand the stress of trying to push the glass to the bed. PLA, just like any plastic, isn't super strong in thin layers, especially when heated to 60°C to get a good bed adhesion. And then you might want to print something like ABS, which demands an 80°C or higher bed temperature. The result will not be pretty: either the clip breaks after a very short time or it starts to bend. The result: no clip, bed slipping free.

Solution attempt one:

Let's look at old picture frames that consist of just a glass sheet and a paper/wood backing. A "Frameless Picture Frame" like this one¹. These clips do need some kind of mounting on the underside.

Using this design as a base, you might either get these clips or make similar ones yourself. But how to mount them?

Well, here comes the nice part: we got some options.

• Glue or solder the clips to the underside of the bed. Removing the sheet gets a PITA, but is still possible
• Cutting mounting slots for the clips. The sheet can be removed by removing the clips now. But the bed heating might not like us cutting slots into the aluminium.
• Adding a mounting point. Again, we can use glue or solder to add some kind of framework that we mount the clips to. Like a piece of aluminium U-profile with the opening to the centre of the bed, giving us mounting points for the clips.

^{1 - This was just the first one that I found that had the right setup. I am not affiliated with them and don't get money for this.}

Solution attempt two:

Take this idea up a notch and look for this same principle applied.

There is the "Swiss Made Glass Retaining Clip" Perplexed Dipole mentioned. Good idea, and instead of having to cut a notch into the aluminium bed, a simple, small hole would be sufficient. About the same price than a frameless picture frame but less construction work!

And then there is, of course, the option to look at the Ultimaker and its Build Plate Clamps like 0scar mentioned. If you can get them (also in the same price range as the other options) you even might have an easy installation: they are supposed to be mounted in the corners of the build plate by being held by the springs. For the A8, you'll have to possibly adjust the mounting point some, maybe even give them a little nub to pivot around to secure them in place, but this clearly is a solution too.

Answer 5

They might not work for every printer, but how about old fashioned bulldog clips:

Attached at both end in the y-axis, they will avoid your Z-axis rods and frame (attached in the direction of the x-axis I have noticed them catch against the Z-axis frame).

Like so (except the image below uses the foldback clips that (I assume that) you refer to):

The lever/handles aren't as long as those on foldback clips, and more sturdy too. Also, they have no curled edge that can catch the nozzle if mounted right.

You should obviously route any wiring/tubes away from the clips travel at the rear of the printer.

Answer 6

I went to OfficeMax and got some Small clips. They are bigger than the Micro/Mini clips that ship with the printer and seem to fit just right on a glass plate.

One of the Mini clips that shipped with the Ender 3 is shown to the left. The Small size that works best is obviously centered. The Medium in the back seem way too big.

For an added bonus, they sell this sandpaper with a rubber back and it really increases traction. An oversize chunk of that worked really well. But it's optional.