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View Full Version : Final Check Before Purchase



DARRELL WOOTTON
08-30-2017, 4:06 AM
Hi,

After 12 months of mulling over buying a laser cutter, I will be placing an order for either a Thunderlaser or Bodor laser.

I have been offered an 80W Thunderlaser or either a 80W or 100W Bodor laser. From what I have read up on this forum and other articles I believe 80W is a good choice for cutting and laser engraving (please correct me If I am wrong). So I am thinking of the 80W for upto 10mm cast acrylic, laser ply engraving and cutting.

One thing that I need advice on, Bodor are claiming 4000 DPI 'Highest Scanning Precision', can anyone explain what exactly is meant by 'Highest Scanning Precision'

Other manufacturers are claiming 500-1200DPI so Bodors 4000DPI seems well beyond what other manufacturers state or have I misunderstood something.

Any advise will be welcome.

Thanks

Daz...

Bill George
08-30-2017, 7:56 AM
I don't think I have ever done over 600 dpi engraving on any of my lasers, past or present. I doubt any Chinese machine would or could do over a 1000 dpi and I can't think of a photo or otherwise that would require that high with a laser. I could be wrong, let others speak up.

Cam Mayor
08-30-2017, 8:26 AM
I do mostly acrylic and very rarely do I go over 300 dpi. By adjusting the step size any setting would be possible but it would do so at the expense of speed. I would also question whether the hardware of the machine was up to 4000 dpi. You would need some awfully tight belts or zero lash screw drives to do that precise. Also if you are cutting thicker acrylic you cannot use as precise of lens, the finer pointed lenses have no focal depth. To cut 10mm acrylic you could probably get away with a 2 1/2" lens but you would do a better job with a 4" lens. This will be putting you into the 300 dpi range just to accommodate the lens regardless of what the laser is capable of.
Probably both will give you all the precision you will need, look at the other features to see what suits you best.

Mike Null
08-30-2017, 9:18 AM
When you look at the spot size possible anything above 600 dpi is pretty much overkill and may actually ruin images on some materials.

Gary Hair
08-30-2017, 9:59 AM
I do a lot of engraving on anodized aluminum and use 1,000 dpi exclusively. The detail I need isn't possible with anything lower and since my Speedy 400 is so fast, 1,000 dpi is still faster than my previous machine at 333 dpi! There is something to be said for a $32K machine vs $3K

matthew knott
08-30-2017, 9:04 PM
1000 Dpi is 0.0254mm that's quite a bit smaller that the beam size of a co2 laser so you will be doing a fair bit of overscanning , so the quality is probably better but not for the reason you would expect ! Bottom line though if it looks better it looks better and the reason is irrelevant

Kev Williams
08-31-2017, 11:35 AM
"4000 dpi highest scanning precision" is basically saying you can enter a scan gap of .007mm (.00027") and the machine will run at 4000 lines per inch... that's splitting 1/1000" 4 times, not sure the steppers are capable of that, but who knows? -At 500mm/s my Triumph will sweep a 4" long line about 3 times per second. This means to engrave a 4" x 1" rectangle at 4000 lines per inch will take 1333 seconds-- or 22.22 minutes...

Dave Sheldrake
08-31-2017, 11:11 PM
quite funny really seeing that a co2 laser has a beam wavelength diameter of 0.0106mm...makes 4000dpi pointless