Piercing?

[Exsecratio]

Just wondering if this is done very much in the trade using Lasers?

Looking at some of the hand sawn pieces here the amount of work involved must be huge! so it got me to thinking if anybody uses a laser to do it?

best wishes

Dave

[Goldsmith]

Hi Dave,

Do you have experience of laser cutting?
If so can you give me an idea of the work and costs involved in writing a program for the laser and then to cut this pattern out of a 1mm. thick, pre shaped silver bowl. Bear in mind that the cost would be for only one item only and not dozens.

James

[Exsecratio]

Hiya James,

A multi direction curved item like that would require a bit of setting up (I don't do curved items,past cylinders etc)

As a general item though I can give you some idea of what would be involved in a flat version.

The design would be a mirror / 6 x repeat so pretty quick to draw in a cad package (only half of one sixth would be required).

From there the file is saved as a DXF format.

The DXF is imported into the lasers software control program and processed (all automatic) and would take maybe 15 seconds for the software to generate a laser ready file.

Cutting 1mm silver sheet would require one of the following types of laser:

CO2 Glass tube 150 watt with Oxygen assist,

CO2 Glass tube 200 watt without Oxygen assist,

Fiber 50 watt with no assist gas,

75 Watt YAG with no assist gas,

Pretty much any machine equipped with the above would do the job as a flat.

Run time? Under a minute or so.

Run cost? (not including machine cost just processing actual cost) maybe £1.50 to £2.00,

A machine from around £9k up would do that as a flat, machines from around £60k upwards could do it as a bowl.

As an example, I just did the following item after starting to write this post, from first thought to finished item including drawing ...10 minutes.(it's 120mm diameter)



The only people who will expound how expensive laser cutting is are the ones trying to see you something

best wishes

Dave

[Goldsmith]

Very interesting Dave thanks for your expertise and info, when my customer enquired about laser cutting these types of bowls three years ago, he was quoted £1200 per bowl. But he was told that the company's laser cutter could not cut the sharp interior points easily and that another machine may be required. He was advised to try another company who used German computer operated router type cutters rather than lasers.

I am glad that I am not chasing work these days as I have no intension of competing with these machines, if that's what people want then let them get on with it. I am getting to old to worry about competing for new work.

Cheers, James

This was one of my flat piercings, 300mm.square.

[Exsecratio]

Hiya James,

3 years ago that would have been around the figure to be expected, over the last three years the bottom fell out of the laser cutting market as machines got cheaper and cheaper (dropping from several million to £200,000 range) While 200K is still a lot more than many people pay for a house they are now in the land of smaller businesses and not so much the realms of the ultra big companies. Now homebrew small form factor lasers can be had for as little as £450 and require no skill to operate.

That piercing of yours is something I could only ever hope to do by hand (I can still hand scrape a surface plate and keep one at work just to remind me and keep my hand in), one of my guys asked me the other day "What you doing it like that for Dave? I'll chuck it in the surface grinder for you if you like?",

Lasers are great and they make me good money (and I always try to remember I'm very lucky considering the current economic climate) but I do wonder at what cost long term.

The following video is real time



There are 81,000 individual lines in the Mayan Calendar used in the video. Imagine doing that with a Graver

best wishes

Dave

[Pedro]

Hi Dave,

Do you have experience of laser cutting?
If so can you give me an idea of the work and costs involved in writing a program for the laser and then to cut this pattern out of a 1mm. thick, pre shaped silver bowl. Bear in mind that the cost would be for only one item only and not dozens.

James

Very nice bit of piercing James, Exsecratio I feel I know you from somewhere how Spooky is that !.

Have you thought about going down the road of peircing/lasercutting the sheet and then in an anealed state form the bowl in a press?. You would have to allow for elongation and making sure the sheet is correctly located on the bottom die and braced as it first makes contact with the former.

In my silversmithing day's I used a similiar technique for forming 0.8mm silver using just a fly press and some foam rubber sheet but it could sometimes move the silver before it formed.

Later when I went into engineering I would prove two part conforming cutting press dies on a power press, much smoother and reliable but hardly something you can fit in your garden shed !.

For one off's or short run's I would always go for hand formed,pierced and polished silver work, it gives you more satisfaction during the making and makes it more unique to the buyer.

Peter

[caroleallen]

That was an amazing video Dave.

I have quite a lot of my stuff cut out by laser. I couldn't run my business if I cut everything out by hand.

[caroleallen]

Your scroll piece looks very smooth Dave. The pieces I have lasered always have a rough raised bit around the edges which I have to file off.

[Anna Wales]

I have to admit to viewing these whizz-bang machines with really mixed feelings mostly negative! Surely they are creating a generation of programmers and assemblers rather than skilled metalworkers? At events I attend I have a step by step of a cross pendant that I made. A chap came over and said that he could cut it all out for me with his machine from China and would I be interested in some quotes. I think he missed the irony when I asked him where he felt that left me and my skills!

[Goldsmith]

Very nice bit of piercing James, Exsecratio I feel I know you from somewhere how Spooky is that !.

Have you thought about going down the road of peircing/lasercutting the sheet and then in an anealed state form the bowl in a press?. You would have to allow for elongation and making sure the sheet is correctly located on the bottom die and braced as it first makes contact with the former.

In my silversmithing day's I used a similiar technique for forming 0.8mm silver using just a fly press and some foam rubber sheet but it could sometimes move the silver before it formed.

Later when I went into engineering I would prove two part conforming cutting press dies on a power press, much smoother and reliable but hardly something you can fit in your garden shed !.

For one off's or short run's I would always go for hand formed,pierced and polished silver work, it gives you more satisfaction during the making and makes it more unique to the buyer.

Peter

Thanks for your comment on my piercing Peter. I am getting a bit old now for adapting to modern methods of making, I like working with my hands and hand tools. I am not intending competing against machine made items.

James