"Some inquiries about cutting MDF with laser" Topic

Inspired by Mantic Games' Dead Zone terrain sprues, I'm trying to make one using MDF, but I don't have the laser-cutting machine. I do have someone who can do it for me though. But working remote, I want to make sure I get things right.

1. How accurate are these machines? I heard when designing MDF buildings designers have to go in several tries. Is this due to the machine inaccuracy? Or design mistake? Or do you have to compensate for additional length especially when MDF panels are placed side by side?

2. How well does MDF hold fine edge? I'm talking about 1mm details. Would it hold 1mm details? Maybe not 1mm… like 1mm x 5mm detail.

3. Say you have two MDF panels sized 5 x 5cm. You place them side by side. I'm trying to create a frame for both panels. Do another MDF panels with a hole sized 5 x 10cm enough for both panels side by side, or do I have to add the length a little bit?

Thanks!

We can cut files for you if you design them.

MDF is kinda easy. Styrene is fun :)

The machines are very accurate. Their isn't any force applied to the motors so they don't skip steps or anything like that.

I design in 3D with sketchup. This cuts down on the design flaws. However, It still takes me 2-3 times sometimes. Box with textures etched on it? Sure first try. Wrapping a complex shape with styrene? Yah that might take a few.

It really depends on how much fine detail you have and your joining methods. If your just using tabs then it's not too hard.

If you talking about etching 1mm lines then it shouldn't be a problem. MDF takes detail very easily. If your talking about cutting a 1mm wide piece then.. don't. Anything smaller then 3mm will probably break.

Parts designed to mate with each other are tricky. If your after a glue fit then it's not a problem. The laser removes material. Usually around 0.015" or so per cut line. Every machine is different so you need to know that number if your going to pressure fit them. Expect 3 or 4 tries for this. Generally boxes and most shapes fit together fine because they have had the same amount taken off on all sides. However, Placing one square inside another has the opposite affect. Kerf from the inner line and kerf from the outer line add instead of canceling each other out.

I can cut a design for you and work with you a bit. We can do some small test pieces before you do the big one as well. That way we know it works. I charge by the minute but with a $40 USD min. I'll also have to charge if I have to do some extensive file conversions or modifications.

Hi Sevej, drop me an email if you like, we can have a look at the design and throw it through the machine if you like. We can then see how it comes out and send you some pics.

On the questions:

1. As CorSec says, the machines are very accurate. The is some trial involved on the design side, to make sure that every piece fits correctly. It's very easy to make a simple mistake, like not allowing for the thickness of the MDF when drawing the design out.

2. If you mean etched details, it would be fine, no problems at all. If you're wanting to cut 1mm detailing, as CorSec says again, it would be too fragile as a piece.

3. This depends on whether you want the frame to be tight on the two pieces?

CorSec has just about said it all. Lasers are very accurate with thin MDF but you do have to experiment to make sure your design (and computer file) and the particular laser cutter work together. Cut, try and then modify the design a few thousandths of an inch.

One down side of laser cutting is that the product STINKS for several weeks of smoldering wood – not nice even if you are expecting it.

If you have a few square feet of spare space you could consider a CNC router such as the Shark – less than US$3000 for the basic model, uses a small router or tool grinder motor and standard carbide bits. The disadvantages are that the detail is much coarser (3mm/.125 inch wide cut line) but the location of the lines is just as accurate. Oh, and lots of sawdust but no smell.

@ bsrlee:

One down side of laser cutting is that the product STINKS for several weeks of smoldering wood – not nice even if you are expecting it.

That depends on what kind of MDF you're using. The cheaper stuff will have a nasty smell, and a sooty residue down the edges which will mark your fingers/clothes/etc, because of the resin holding it together. There's laser-specific MDF available, which gives a much nicer finish.

Thanks for the replis!

The mm details are something like these examples:

Not actual design, but something similar. The one one the left is buttress for wall. It has 1mm x 5mm teeth. Would this possible?

The one on the right is a panel, with two tiny holes (each 2 x 4mm) and tiny bridge between the holes (2mm wide). Will the MDF break? The idea is that this is the floor and the the wall will stand between the two holes while two buttresses clamp the wall from both sides (hence 1mm teeth) and inserted into the holes.

This is just an example though. I'm still thinking of other alternatives that may not require these tiny details are more error-proof, but'd like to know the boundaries of possibilities.