Garden Railway Forum

I cut a lot of decorative items from 2mm mild steel for one of my customers. Some of the items are irregular shapes and even when nested there is a fair amount of leftover material. I thought I might as well put that to good use so at long last I've started playing around with designs that utilise the capabilities of the laser. The aim is to make a chassis where parts can be bent by hand and bolted together. No need to machine frame stretchers, thread holes etc. This is the first proof of concept I have done. The frame parts are aligned using slots and tabs. The stretchers have slots cut in them so they can be bent by hand. Works well so I'll take that idea further.

Nice start BB.
Designing for laser cut always seems so easy until you draw up the lines.
How wide is a laser cut? When you draw a hole how big should it be so it can be reamed but not oversized? How much allowance for extra length is needed for bend allowance? Assurance from the local laser man that these dimensions are ‘negligible’ is not much help. To bad we are a hemisphere away.
Tim

The cut width (kerf) varies with nozzle size, gas pressure/type, stand-off etc. but generally tolerances are within +/- 0.1mm. If I want to ream a hole to 3mm I cut it 2.7mm.

Bend allowance is more tricky - there are formulas for that. Nothing to do with the laser really. However when I cut slots to aid bending, the final width is pretty much spot on distance between center of slots + 2 X material thickness.

Thanks BB,
Looking forward to your progress.
Tim

Do you think you are able to produce a multi height coupler like this but as a one piece unit in steel?

https://www.maidstone-engineering.com/o ... -aluminium

No, that would require casting or 5-axis CNC machining.

An intriguing use of scrap. Looking forward to see what comes of it..

Busted Bricks wrote: ↑Mon Feb 03, 2020 10:02 pm No, that would require casting or 5-axis CNC machining.

On the grounds there are no stupid questions, only stupid answers..

What makes it '5-axis'?

I 'get' 3-axes - X, Y, and Z..

Phil. P

A,B are 4 and 5.

X and y can both rotate which makes it a real 3D machine. X,Y and Z is called an 2.5D

Search on Youtube for "Hermle 5 axis"

Thanks..

Pity all the Technical Colleges stopped and doing night school classes on metal working and machine tools..