"Perfect Fit" with Lasercam and Techsoft Beam Dia

Help, advise and examples created by the Universal Laser Systems (ULS) VersaLaser laser cutting / marking machine supplied by Denford

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"Perfect Fit" with Lasercam and Techsoft Beam Dia

Post by bradders » Tue 08 Jul , 2008 11:54 am

I require to get "Perfect Fit" of mating parts with Lasercam and Techsoft
Last edited by bradders on Thu 23 Oct , 2008 16:00 pm, edited 3 times in total.

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Post by bradders » Tue 08 Jul , 2008 11:56 am

To get a "Perfect Fit" of components
1. Lasercam
Select the "CREATE OFFSET PATH" button and type in 0.07mm (Approxiamate RADIUS of the Laser Beam)

2.Techsoft
Select the "CONTOUR PATH" and type in 0.07mm (Approxiamate RADIUS of the Laser Beam)

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Post by Denford Admin » Tue 08 Jul , 2008 13:34 pm

ie, A laser does have a cutting diameter, so if you cut out a circle of 50mm diameter, its actual size would be less:

49.86mm which is 50mm - (2 x 0.07mm)
{Edit - this is incorrect - should be 1x0.07 = 49.930}

Also bear in mind that a laser does not cut perfectly parallel sides, so getting "perfect fit" results will vary according to material thickness.

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Re: "Perfect Fit" with Lasercam and Techsoft Beam Dia

Post by KeithJamison » Wed 21 Jul , 2010 7:47 am

so if you cut out a circle of 50mm diameter, its actual size would be less:
May I clarify something please?

If I remove a circle of diameter 50mm from a sheet of acrylic, the diameter of the hole will be 50mm but the acrylic 'plug' will be 49.86mm?

If I require a plug to fit the hole 'perfect fit', do I cut a hole that is diameter 50.14mm, leaving me with a plug that is 50mm diameter?

I realise that it is all internal and external dimensions.

Many thanks.

Keith

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Re: "Perfect Fit" with Lasercam and Techsoft Beam Dia

Post by Denford Admin » Wed 21 Jul , 2010 8:35 am

Having looked again at my previous post and it's incorrect, I should have put:
It's actual size will be 49.930 (1 x 0.07mm)

So if the laser is following the centre-line of a 50mm diameter hole, the "plug" would come out at 49.930mm and the hole would be 50.070

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Re: "Perfect Fit" with Lasercam and Techsoft Beam Dia

Post by KeithJamison » Sat 24 Jul , 2010 11:22 am

Denford Admin wrote:Having looked again at my previous post and it's incorrect, I should have put:
It's actual size will be 49.930 (1 x 0.07mm)

So if the laser is following the centre-line of a 50mm diameter hole, the "plug" would come out at 49.930mm and the hole would be 50.070
We have a VLS 3.5.

I have found the following offsets to work for me. I guess it is trial and error. I recently completed some test fitting on a range of pieces.

Cut a 20mm circle out of 6mm acrylic. Cut a 20.95mm plug from 6mm acrylic for a very tight fit. 20.90mm for a better fit that might reduce the possibility of a crack forming. I tested 20.35, 20.40, 20.45 and so on up to and including 21mm.

Contrast that with...

Cut a 20mm square (or 20x30mm rectangle) out of acrylic. Cut a 20.35mm square plug to fit the 20mm square cut out (20.35x30.35mm plug for the rectangular cut out).

Cutting a pentagon or hexagon out of acrylic and cutting the same piece with an external offset of 0.35mm for a snug fit.

A 20.35mm circle falls through a 20mm hole.

I have also experimented with several non-regular polygons and all are fine with a 0.35mm offset.

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Re: "Perfect Fit" with Lasercam and Techsoft Beam Dia

Post by bradders » Wed 28 Jul , 2010 8:12 am

Keith,

Thanks for your testing and feed back on the forum, it's appreciated.

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