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How to - calculate cost

It's one of the perennial questions, how much will this cost to be lasered?

How long is a piece of string, it isn't a hard and fast answer, but we can give you some useful guidelines. Let's start with the Exeter Laser charges. We charge in "machine time", which means exactly what it says, how long your job is in the machine being lasered.... our charges are...

  • £50 per hour of machine time, billed by the hour.
  • £1 per minute of machine time, billed by the minute, minimum charge 10 minutes.
    • All the above ex VAT

Which doesn't help you a lot if you do not know long a laser will take to do the job you want, which brings us to...

LASER ENGRAVING (Raster)

Raster engraving is what people think of when they say laser engraving, in 99% of cases.

Raster engraving is simple to estimate costs on, we will take a design size area of 100 x 100 mm, which is approximately 4 x 4 inches.

It doesn't matter if the design to be engraved is a letter that fills that entire block, or a line drawing or anything else, it does not matter at all, for raster engraving, what the design is, all that matters is the area the laser has to cover, which is the design size area.

We have chosen 100 x 100 mm or approximately 4 x 4 inch, but the area is what matters, so 100 x 100 is the same as 50 x 200 is the same as 25 x 400, but 100 x 100 is a nice area, anyone can cut it out of a piece of paper and see how many of these squares are needed to cover the whole design, and therefore the cost... or.. just do the math.

100 x 100 mm.

At 400 mm/sec laser speed and 0.1 mm per line, which is suitable for things like marble and slate, it takes about 4 minutes in the real world, and as you can see from the pricing above, that works out around £4

At half the speed, 200 mm/sec, which is suitable for some woods and denims etc, it takes twice as long, about 8 minutes, and so costs around twice as much, eg around £8

Pretty much every other material will fit somewhere between these two speeds, and therefore cost, we do our edge lit acrylic signs at 300 mm/sec and we do most woods at 300 mm/sec, which works out at 6 minutes and £6.

Double the area, double the price, halve the area, halve the price.

To a certain extent, doubling the speed halves the price, and halving the line spacing, (eg from 0.1 mm per line to 0.2 mm per line) also halves the price, but a word of caution here, we have settled on the feeds and speeds that we use because you get a nice blend of job time vs finished product quality on our machines with given materials, stray too far outside this and quality drops off sharply.

Laser power of course varies from job to job and material to material, but it makes no difference to the job time, and we charge for time, so you can discount the laser power from the cost calculations.

Vector Engraving and cutting.

Vector engraving and cutting are in many ways the same thing, instead of going left right, left right, left right, the laser follows a path.

Time = cost and therefore the factors are length of the path the laser must follow, divided by the laser speed in mm/sec.

Cut paths lengths are much harder for the average person to calculate, but you can kind of correlate from area again, although cut speeds in mm/sec are slower than raster engrave speeds, very much so for the thicker materials to be cut, eg as low as 2 mm/sec for 25 mm thick acrylic, the length the laser has to travel is very much shorter,....

So if we take the letters EL and render them in the font Copperplate Gothic and scale them so they just fit inside our 100 x 100 mm square, if we raster engrave them at 300 mm sec the job will take just under 4 minutes, but, if we vector cut or engrave along the outline of the letters at say 7 mm / sec cut for 5 mm thick acrylic, the job time is just under two minutes... it's actually about a 700 mm line length to trace around those two letters as a matter of interest.

Just under 2 minutes = just under £2

So again we can see that generally speaking, as a rule of thumb, if you take the raster engraving numbers above per 100 x 100 mm, or 4 x 4 inch of design area, you can pretty much estimate your machine time costs, and feel fairly secure that there aren't any "Oh...!" moments further down the line when it comes to getting an actual quote or bill from EL.... as in 99% of cases your estimates will be equal to or higher than the actual final costs.

Note bene, all of the above is based on EL Machine Time, it specifically excludes everything else, such as materials, collection and delivery, packaging, design work.