Hoisted on me own Pitard

[George Elston]

Help! I did some promo pieces by taking photos of some local businesses and etching the storefront on some scrap leather circles I had laying around. It was a great way to get in the door, but it worked too well. Many of the owners would like to buy more to use as drink coasters, and I have no supplier. Does anyone know a supplier for leather coasters? All I see on the web is finished product with logos embossed etc. I need plain brown leather 3/16 to 5/16 thick and around 3 in in diam. Any help would be greatly appreciated. It's summer here and sales are slow, this would help get us through to fall, when the snowbirds come back with their money.

[Mike Null]

George

If you're in the US just check for a leather supplier in your area. Tandy is one which comes to mind.

The thickness you want will be premium in all likelihood. But you can cut it with the laser.

[Bob Cole]

There are several topics on laser in this forum. It is something I would like to explore with. Here is a couple that I found by searching this forum "leather laser".

Tandy Leather http://www.tandyleatherfactory.com/
Springfield Leather http://www.springfieldleather.com/
Siegel of CA https://www.siegelofca.com/default.asp

I've only purchased from Tandy because there is a store where I live. I first went through their scrap bucket and paid $2.50 per pound. Sometimes can get some really good scraps for testing.

I haven't done a lot, but tried cutting some thick leather and got 9/10 through but couldn't go any deeper even with a second pass. Could be my inexperience and settings. I also have a 1.5" lens so may need to readjust the focus to get all the way through.

Good luck. I would be interested in what you find out.

[Vicky Orsini]

I don't know how well leather will hold up as a coaster. You might want to look for cork suppliers. The image should laser onto cork just as nicely. If leather is a must, then I would also recommend Tandy. Look at their on-line store. They sometimes have good, unadvertised deals on items such as these, and the local stores have to honour the on-line prices.

[George Elston]

Thanks to all. I didn't think of Tandy on the web. There was a local store for years, and when they closed I kind of thought they were gone. Just ordered 100 3.25" circles from their web site. Cost came to about 55 cents each, which is doable with a sell price of $3.
I had the same problem with cutting leather, could get 99% through and then nothing. Took the ppi down to 300 and now it cuts like butter. ULS VLS 2.3 with 30 W and the HPDFO lens and run @ 100% pwr, 3% speed, ppi 300. Should work the same (more or less) with other lens as focus didn't seem to effect the outcome, but the High definition lens sure does some beautiful detail on the leather. Will post a shot when I get the delivery.
Thanks again to all.

[Bob Cole]

I was curious about the HPFDO optics. I didn't purchase it with my laser. I currently have a 1.5 and 2". I've only had the 1.5 in the machine.

If you wouldn't mind PM me with some of the differences between the 1.5 and HPFDO optics, I can see if it would be worth purchasing.

The ULS rep said the HPFDO optics are less forgiving when it comes to settings and focus and for most jobs, a 1.5 or 2" is better. The Aztec calendar that ULS provided had the entire calendar in the size of about a nickel.

[rick woodward]

Hate to Butt in here, ..but... i would like to know/see the difference between those optics also. And a good pic of the Whole ? aztec calender the size of a nickel???? WOW ! If anyone would be so kind, i thank you in advance. rick
rcarves ( at) hotmail.com (rcarves@hotmail.com)

[Bob Cole]

Oops. it isn't the size of a nickel. I went and grabbed the sample and it is the size of a half-dollar.

Will post an image in a little bit

[Mike Mackenzie]

Rick,

Here are a couple of pictures they are very hard to photograph due to the size. This is only 1" diameter.

This was done with the HPDFO into maple the real difference between this optic and any others is the spot size is 0.0013 and it focuses at 2.0 inches. This is why the focus tolerance is very tight.

This optic has some very good uses however it is not recommended for everything. I would recommend to see one in action to be sure it will do what you want.

The second picture I took through a magnifying glass to see if I could show some of the detail.

And Bob it is the size of a quarter.

[rick woodward]

Thanks Bob, i'll be lookin for it. Mike you forgot to upload the pics ? Thanks.

AAaand edit....... I see them now mike. Thanks, they look good for a pic. I'd like to see that for real sometime. Maple , Hmmm.

[Bob Cole]

Hope these turn out.

[George Elston]

I am glad I got the HiDef lens, but I have to admit it is pricey(@ 3K). The difference is most evident in etching glass, marble, etc, and there is a little depth of field for the focus, so I can handle curvature (about .156" +or-, depending on the wind;-). Some jobs like cutting detailed filigree and inlays are only possible with this lens. Contrary to ULS ads, I have not been able to mark stainless, to any usable degree, if you hold the piece in the light and look just right you can kind of see it, but I have not tried many different flavors of ss, it might work better on some. On the whole with the choice of putting the initial investment towards the HDPFO lens or getting a bigger machine, most of the time I think I made the right choice. It will do actual photographic quality etchings, to the point where I no longer bother with Bitmap (1 bit) files, but do everything as greyscale.
I am also not sure about the power claims, although it should be true, (the math works out). The actual power at the cutting point of my 30W laser should be closer to 60W, since the beam is concentrated to half its size. But not having experience with a 60W unit, I don't know. I have noticed that when cutting thin acrylic, I have to keep the speed up and the power down or it cuts and welds all in the same moment ( yes I should be using the 2.0 lens for cutting plastic, but sometimes I get lazy). Thought I might try the bottom to top cutting I saw mentioned here.
Will try and post some pics. Hope that helps

[Mike Null]

George

I'd be interested in knowing how you arrived at getting 60 watts of power from a 30 watt machine.

I do not believe a smaller spot equates to higher power.

[Rob Bosworth]

A smaller spot size does not equate to higher power. A smaller spot size equates to higher energy density and less material having to be removed.

[Michael Kowalczyk]

George

I'd be interested in knowing how you arrived at getting 60 watts of power from a 30 watt machine.

I do not believe a smaller spot equates to higher power.

Hey Mike and others,
I read the info on the ULS website about this HD lens and to put it in simple terms it would be like a garden hose. If you have no nozzle on the end it will flow out with lots of volume but no pressure. If you have a nozzle on it and shrink the diameter of the orifice you will be able to squirt the water farther but you will not get the same volume. Kind of like a water jet in theory. No increase in volume but definite increase in PSI because it is concentrated by a smaller diameter orifice.
I printed the info to see if it can be applied to our Trotecs but for 3K, from what george said, that's a bit pricey for now but good to know. Thanks,

[George Elston]

George

I'd be interested in knowing how you arrived at getting 60 watts of power from a 30 watt machine.

I do not believe a smaller spot equates to higher power.


Mike

You are correct, it was poorly stated, and as I said I have not noticed a great increase in "apparent power", with the lens. ULS was saying that it was the only CO2 laser that would mark stainless and I have not seen this as of yet. However!!! the detail is fantastic, and it does seem to have a little more PUNCH, than the 2.0 lens. All in all, for the type of work we do, which depends on the WOW factor, I think it was a good investment, but if you don't have need of a .001 line then it is overkill. Actually a lot of the stuff I do is imaged a 500ppi, and still has much more detail than the 2.0 lens.

[Mike Null]

George

Not all stainless will mark. I have found that the lower quality stainless is easier to mark and actually works out pretty well. For example, if you have a ss ruler give that a try. On the other hand a high chromium, nickel content stainless will probably be very difficult.

If you're rastering it try 1000 dpi as your resolution and a very low speed with full power.

I have a Trotec 45 w with 2" lens and I can mark stainless.

I can understand how the HD optics are an advantage for certain work.

[Brian Robison]

Mike,
you doing that without Cermark?

[Mike Mackenzie]

Mike,

It is the Carbon content of the steel that makes it work or not higher carbon = darker marks.

George,

In order to mark the stainless you have to run real slow 5% speed at 100 power 1000 / 1000

It is not an effective way of marking steel unless the marks are small. You can actually do the same with your standard lens.

[Mike Null]

Brian

That's straight on marking--no Cermark.

Mike

You said it better than me. When you have a high nickel/chromium content I would guess you would have a lower carbon content.

Do you think it would be accurate to say magnetic stainless would be engravable?

[Mike Mackenzie]

Mike,

I believe that all stainless is magnetic the carbon content does not effect that part of it. The higher the carbon the easier to machine and a stronger metal.

Basically all knifes whether it be for the kitchen or for fishing usually have a higher carbon content.

Most drill bits, end mills and machine tools have higher carbon content. It all comes down to how easy the metal can be machined.

Actually I was wrong on the machining part of it here is a quote on the carbon content in steel

Carbon (C), although not usually considered as an alloying element, is the most important constituent of steel. It raises tensile strength, hardness, and resistance to wear and abrasion. It lowers ductility, toughness, and machinability.

[Mike Null]

Mike

From jobs long ago things like stainless flatware (knives and forks) which have designations like 18/8 or 18/10 referring to the nickel/chromium content are non-magnetic.

[Frank Corker]

On a slightly different note, I am asking because I don't know, the title for this post is "hoisted by me own pitard". I'm unable to find out what a pitard is and as there is no reference to it in the dictionary I'm curious.

Where I live, near Liverpool UK, it is common phrase to say "me Dad" or "this is me wife" substituting the word 'my' for 'me' and often brings a bit of a smile to people outside of where we live because it is unusual.

I do get the gist of what the topic is about (down there for dancing mate!) but the pitard eludes me.

[rick woodward]

I could be very well mistaken Frank. But here goes from Indiana... LOL. A pitard , i think, is another English word for a lance. I think.. As in; a knight in battle was speared by his own lance and hoisted up, impaled. rick

[Frank Corker]

Oh right. I was thinking it might have been some sort of hangmans gib. Either way it doesn't sound too comfortable

[Mike Null]

petard

DEF.

hoist by or with one's own petard, hurt, ruined, or destroyed by the very device or plot one had intended for another

edit: here's a better one

Word History: The French used pétard, "a loud discharge of intestinal gas," for a kind of infernal engine for blasting through the gates of a city. "To be hoist by one's own petard," a now proverbial phrase apparently originating with Shakespeare's Hamlet (around 1604) not long after the word entered English (around 1598), means "to blow oneself up with one's own bomb, be undone by one's own devices

[Frank Corker]

Okay, a PETARD - George's fault he said Pitard - a small incendiary device used by the French in WW1 - got it now. Sorry I think that makes it sound like it's all clear to me now... I didn't know what it was or heard of one until this message - so I go home a little wiser. For those who are just as lacking - here is what one looks like

[Belinda Barfield]

petard

DEF.

hoist by or with one's own petard, hurt, ruined, or destroyed by the very device or plot one had intended for another

edit: here's a better one

Word History: The French used pétard, "a loud discharge of intestinal gas," for a kind of infernal engine for blasting through the gates of a city. "To be hoist by one's own petard," a now proverbial phrase apparently originating with Shakespeare's Hamlet (around 1604) not long after the word entered English (around 1598), means "to blow oneself up with one's own bomb, be undone by one's own devices

Mike and Frank,

Thanks so much for the education. I have to admit, I'm still laughing. I do not hear this phrase frequently, but do hear it on occasion here in the South. Here, is the funny thing, we have a similar (but very different) definition. I'm sure it is one of those typical Southern corruptions of "furrin" words. As it is used here it is understood to mean ruined or destroyed by use of a portion of one's anatomy - still essentially the same thing I am thinking.