So I tried to build it today with a friend and the acrylic parts cracked when I tried to adjust for the wheels. So I glued it and used some 3M tape. But then the other side plate broke when I mounted the X rail on the Y rails... Sorry to say but I think you will need aluminium gantry plates. I'm going to machine some on my Xcarve if I can find the STLs. But I think you need to rethink the idea of using plastic parts !

 

Thank you. I'll give it a shot but I think Alu plates would be better...

 

Hi WildBill,

I'm building a laser engraver using the Acro project but trying to make it as chap as possible, so I'm going to regular aluminium profiles and this plastic white wheels, like on your pic, the rest is basically the Acro plan, with some adjustments on the plates to fit the new wheel diamenter. Can you give some feedback of how this system performs? and how it compares to the Acro, since you seems to have both now.

Thanks!!

K.

 

How hard would it be to put nema23's on this build? Or what would I be looking at max move speed (not cut speed)

 

What’s the difference between NEMA 17 and 23 Stepper Motors what’s best to cut aluminum and wood etc.

 

I want to use the 1500mm version with a plasma cutter and would like to get 100ipm cutting speeds

 

if I keep the base design using the files but modify the plates a little bit to fit nema 23's and make the plates out of aluminum/steel instead of acrylic do you think the frame design would be sturdy enough otherwise?

 

Now that’s cool, our shop has a big one we burn out duct fittings on it all the time

 

The laser engraver you saw in the picture I got from BangGood 1 1/2 years ago. I had to modify the gantry's that came with it - making the holes for the wheel's into slots so I could adjust the wheel tension to get as much slop as possible out. It took a while but I got it working fairly well. But I replaced all the rail's with openbuilds rails (I made it 2'x3'), different laser, and different electronics to support the Z azis. So those gantries and wheels is about all that is left of the original system.

The positive things about the ACRO design that I like are having the motors low to keep the center of gravity low, as always I like how the OpenBuilds wheels roll on the rails, the gantries are designed to allow easy wheel adjustment. I like the ACRO system better because everything moves much more smoothly and quieter. It does not have the small jitter that I find with the other system which gives cleaner burns.

So my conclusion is that while the ACRO system cost's a little more than the low cost imports it is worth paying the difference. I spent more upgrading the low cost system than I spent on the ACRO system. Spend the money on good wheel's and stay away from the white hard plastic wheels - it will be cheaper in the long run. Also not all other rails have a wide enough opening for the G2 belt to work smoothly, I learned that the hard way and had to get more rails that would work.

On a different note I installed the Z-axis on the ACRO system today (pictures to come soon) and if I push I found that I get a little twisting in the Z-axis itself with no movement on the X-axis. The reason I like the Z axis is I etch a lot of different things that have different thickness. It is a pain to keep refocusing the laser so I keep the laser at one focus point and raise and lower the Z-axis to get the correct distance. I made a small wooden dowel the correct length and hold it on the material I will etch and adjust until the laser just touches the top of the dowel. Must easier than focusing.
Oh - on the BangGood system the X-axis would flex and not the Z axis.

 

Here is a picture of the Z-axis installed. I made a couple of new holes in the X gantry and mounted it directly. I can now get all the height that I need and only cost $35.00
One of the few times the cheap way works well because its so light.

 

What laser do I need for etching on aluminum? I plan on anodizing the aluminum and spraying it with CerMark Metal Laser Marking Spray.

I don't need to cut or anything else but etch. What is the cheapest laser setup for this?

How many inches per minute does it need to travel? I might just put it on my CNC router.

 

Etching directly on any metal is not that easy. There are two two things messed up pretty often. Marking and engraving.
Simplifying: Marking = changing of the colour, engraving = removing the material, etching is more like removing of course.
Using a spray - we did not test this, but this may work, I will write to the producent to get some samples for tests.

Anodized aluminium is possible to engrave (since we remove anodized layer) but anodized layer should be a little darker. BUt even gold enodization works. Here are the results for example:


It was done wit ha speed of 50mm/s and beamspot size around 0,2mm diemeter.

Using 6W (2,8 can work too but is barely visible) you can mark stainless steel or titanium, but not other metals.
You can see that focus distance changes the line width. Short focus make the line more equal in both directions but it isless visible (even with higher power density). Speed used - 3mm/s

 

Thanks. I'm needing to mark the aluminum.

Labels on a control panel.

 

If you anodize aluminium to black you can do this easily with nice effect.

Bare aluminium you can paintwith black paint, remove the paint with laser and etch the aluminium with acid or sodium hydroxide. It will etch only the places where the paint is removed.

It depands what effect you would like to achieve, there are few options. Of course you can just mill the label using engraving end mill, or you can etch aluminium the way I mentioned.
You can also paint the etched area which become rough or use the label printer

 

How hard do you think it would be to put an adjustable Z on this thing? Even if it was just a manual Z Axis.

 

Look 6 posts up from yours

 

I ordered an Acro, which is slated to arrive in a few days. This is my first venture with OpenBuilds, and I'm looking forward to it.

I will be using an Arduino with CNC shield, GRBL 1.1, and an Eleksmaker 2300mW laser for the system. If the Arduino doesn't work out, I'll switch to a Smoothieboard.

 

You'll be fine with the combo of hardware your using. I just finished building a Acro 1000mm x 1000mm 2 watt system. Works flawless. You'll be fine

 

My Acro kit arrived over the weekend - in other words, more quickly than expected. Still waiting on the laser, and I also ordered a genuine Protoneer CNC board to be sure that GRBL 1.1 would be supported. Now comes the hard part - I really don't have time to assemble this until Tuesday night at the earliest, if then. I hate waiting.

In the mean time, does anyone have thoughts on air assist with respect to diode laser systems?

 

Is this setup suitable for a router?

 

*maybe* a dremel. you'd want something a bit stronger for a router (e.g. OX)

 

Thanks. I kinda figured that out.

 

Has anyone thought about building a variable height Z table to go under the Acro system rather than a z axis on the laser? If so, please share, if not. I might have to come up with something as the laser I bought does not have an adjustable focus point.