Modifying the Acer X152H Projector to work with a DLP 3D Printer

Why the Acer X152H

It’s relatively cheap, It’s 1080p and it’s easy to modify for short-focus. Also, it’s pretty much the only option (as of Jan 2016) if you want an HD image that is crisp across the whole build plate. There are other projectors that are HD and do not require modifying, but you will get blurry corners or worse. I tried an Acer H6510BD and about 1/4 of the image was unusable and blurry.

What is this modding all about

The goal is to get the projector to be able to focus on a target that is very close to the lens. The projector was not designed for this, but fortunately it’s relatively simple to hack it to do so. The downside is that once modded, the projector won’t able to focus on distant objects. You won’t be able to use it as a normal projector anymore. However, the modification is easily reversible.

Here we go

Take a deep breath, you are about to crack open and mess around with a brand new $500 device. It’s going to be ok. (or not, and if you mess up it’s not my fault and you can’t sue me, please don’t sue me)

Here is our patient:

Remove the focus ring, it just pulls right off. No screws.

Open all the screws on the bottom, you will need a long Phillips screwdriver. Warning: they are really hard to unscrew, get a good screwdriver so you don’t strip the screws. If you do, you are screwed.

Open the lamp cover, take off some weird plastic transparent thing that’s glued there, and pop that white power connector out of its resting place. No need to disconnect it, just get it out of that nook.

The top plastic cover should come off now, but will still be connected to the main board with a few wires that have plug-in connectors. Disconnect all the wires and set aside the cover.

Projector should now look like this:

Our goal is to remove the lens assembly, which I have professionally marked with red in the next picture, and “shim” it. We’ll be putting it back where it was, only pushed forward by a small amount. This will change the focus distance of the lens.

The lens assembly is held in place with four M3 bolts. The bottom two are not accessible, a plastic ‘wall’ is blocking them. You have two options now. You can cut the plastic and bend it a bit, as seen in the next image, or you can dissassbmle the whole optical module of the projector and remove it from the plastic housing. I opted for the first option, but the second option is valid and not that complicated. It’s your call.

Open all 4 bolts and remove the lens assembly. Replace the bolts with slightly longer M3 bolts, and put two M3 nuts between the lens and the projector. This will be our ‘shim’. Should look something like this:

You will need to remove the zoom ring (the gray plastic thing on top). It’s connected with three small screws. Keep all parts you take off and the original four M3 bolts that held the lens. Put them in a box and mark it. If you ever want to revert your projector back into normal operation mode, you will need those parts.

Connect the lens assembly back to the projector, it should look like this:

You will still be able to change the zoom, using a small screwdriver inserted in that white plastic tube.

Put everything back together, and now you should be able to do this:

It’s really bright and can hurt your eyes, so please use a filter when focusing the projector. Also, once you have the zoom set, cover that top opening with opaque tape. You don’t want UV light spilling out from there.

Next post will be about how to modify the LittleRP to mount the X152H. Don’t worry though, It’s a lot simpler than modding the projector.

Taking it to the next level

There is more you can do to this poor projector, if you are brave and technically inclined. The color wheel can be relocated and the bulb UV filter can be removed. Both will increase the UV output and reduce cure time. Some people go as far as replacing the bulb with a UV LED light, but I have not yet found any solid information about this. If you have done this, or know someone that did, please post some links in the comments.

Nün&Noot