PDA

View Full Version : Rubber Stamps with a Galvo



Robert C Kelly
10-07-2013, 2:40 PM
Hi Guys

This is first post so please bear with me. Have a rubber stamp business and want to move away from the old way of photographic negatives and moulding boards - messy, time consuming and so many possibilities for errors and failures in the processes. Have been considering lasers for some time and investigated and had demonstrations from various manufacturers (Western models).

I've read many threads on here about Chinese versus Western and have still to make up my mind when suddenly along comes another possibility - the Galvo.

Have received quote of $6400 fob for 60w CO2 Galvo but have read about larger spots than with a flatbed and wonder if the Galvo will be suitable - anyone on here have any experience in this field?

The spec on the Galvo shows the following:

Min. line width (mm): 0.2mm
Min. character size (mm): 0.5mm
Repetition accuracy (mm): 0.01

The spec on a flat-bed from the same source quotes:

Minimum shaping character:English 1 x 1mm
Resetting positioning accuracy:0.05mm

(Obviously written by different people) but the Galvo would appear to offer better definition and spec or am I missing something.

If this has already been covered then I apologise and would appreciate being pointed in the direction of the article.

Appeciate anyone's input on my dilemma

Many thanks

Bob

Steve Clarkson
10-07-2013, 3:31 PM
Hi Bob.......I can't help you with your galvo question......but I can say that making rubber stamps with a CO2 is a nightmare......they come out perfectly......but it completely trashes your laser......the dust gets everywhere......it stinks (no so badly with the no odor rubber) and you literally have to clean the laser after you make a stamp. There MUST be an easier, faster and cleaner process.

Scott Shepherd
10-07-2013, 3:58 PM
Hi Bob.......I can't help you with your galvo question......but I can say that making rubber stamps with a CO2 is a nightmare......they come out perfectly......but it completely trashes your laser......the dust gets everywhere......it stinks (no so badly with the no odor rubber) and you literally have to clean the laser after you make a stamp. There MUST be an easier, faster and cleaner process.

There is, use a Trotec :) and the right material. Stop using the laser rubber and use the laser photopolymer material. Honestly, the Trotec has an OUTSTANDING stamp setup. I cut a bunch of them last week. So easy. Love that feature on the Trotec, not to mention it's all sealed up tight so the dust, even if you do use the rubber, doesn't get anywhere but inside the cabinet. A quick wipe and it's gone.

Mike Null
10-07-2013, 5:18 PM
Steve is correct. this from the Trotec site.


Trotec Laser was founded in 1997 in Marchtrenk (Upper Austria). It was developed from a research branch of its parent company Trodat, the world's leading manufacturer of self-inking rubber stamps.

matthew knott
10-07-2013, 5:34 PM
Spot size on a co2 galvo is much bigger than a XY plotter style laser, to compound this problem a chinese glass laser will have an even bigger spot. You will end up with a pretty small working area, think of something like a 4 inch square. It might be ok, it might not, I would be worried about the resolution you will get. Galvos much easier to keep clean, normally as you only have to extract fumes from a small area, plus lens is further away.
Scotts right use the right material, if you use the wrong stuff it stinks and makes a terrible mess.

Dave Sheldrake
10-07-2013, 6:15 PM
Got an even bigger headache now Bob? ;)

cheers

Dave

Chris Edens
10-08-2013, 12:45 AM
There is, use a Trotec :) and the right material. Stop using the laser rubber and use the laser photopolymer material. Honestly, the Trotec has an OUTSTANDING stamp setup. I cut a bunch of them last week. So easy. Love that feature on the Trotec, not to mention it's all sealed up tight so the dust, even if you do use the rubber, doesn't get anywhere but inside the cabinet. A quick wipe and it's gone.


I second this post. I have 2 speedy 300's and make stamps all day on them. If you want a real inexpensive way to make stamps you could use the flash method. The flash machine makes about 100 stamps an hour and was about 4k but it only makes stamps. The only reason I have a flash machine is to make TRIO stamps.

http://ssl.distone.com/MillMarking/index.asp?se=471519821&cu=t&slm=&usr=t&tpl=itCategory&cat=291

Robert C Kelly
10-10-2013, 1:46 PM
I second this post. I have 2 speedy 300's and make stamps all day on them. If you want a real inexpensive way to make stamps you could use the flash method. The flash machine makes about 100 stamps an hour and was about 4k but it only makes stamps. The only reason I have a flash machine is to make TRIO stamps.

http://ssl.distone.com/MillMarking/index.asp?se=471519821&cu=t&slm=&usr=t&tpl=itCategory&cat=291

Note - I wrote a large missive in response to everyone's input but when I posted it the site crashed and when I finally got everything back I discovered that it hadn't posted and my writing page was blank. I couldn't face writing it all again and then today I thought how rude it was so went back - in so doing I also found a saved draft which although was not the complete original it got me off to a good start and here it is. Apologies for the delayed response.....

Many thanks to all who have responded and comments, even if, as Dave rightly says, I now have a bigger headache!! I am aware of the Trotec systems and have had a demo with the Speedy 300 and the Rayjet. I don't know if I caught them on a bad day or they were anxious to get back on the road but I wasn't really impressed.

The Epilog demonstration was a farce because although the purpose of the demonstration was to show the machines making stamps, the agent had no rubber!!

I have also had a demonstration on a GCC which seemed to do the job, and if I had not made other appointments, I would probably have bought one on the spot!! but I moved on. Another demonstration with a well established Company selling lasers who could not get the settings right to make a stamp - it was either too shallow or he ended with a warped and twisted goo.

In none of the demonstrations by sales companies have I been particularly impressed but I have had a demonstration last week where a non sales person took his laser and produced a good stamp at the third attempt from scratch - so it does work.

I have used the flash system pretty well ever since it hit the stamp scene and have been through a few machines in that time. Yes, they have their place - I use them as a substitute for pre-inked stamps which I loathe and detest as they are so fiddly and messy to assemble. If a customer insists on a pre-inked stamp I farm it out to an another supplier!! Flash stamps are also convenient when a customer wants a stamp in a real hurry (we can produce one in about 10 minutes start to finish). I'm not quite sure how you do 100 an hour Chris unless possibly they are all the same and you have a very big flash machine. I've used the Maxlights in the past for the larger mount sizes but have now have shifted to the Colop EOS range. I don't find them particularly cheap either - perhaps I'm buying from the wrong source!!!

I guess the dilemma is always the same - pay an absolute fortune for a Trotec system (I was originally quoted 25k for the Speedy 300 - the price has reduced somewhat from there but still way ahead of anyone else's price). With no experience of laser machines it's hard to see the added value in the Trotec system at way more than double the price of the far Eastern offerings. Yes there are certainly attractive features like their protected internals requiring reduced maintenance but I would certainly question the statement in one Trotec video that I have seen on You-tube where the salesman stated that it meant they were "virtually maintenance-free" - I don't think he has worked with rubber stamps - but maybe you could come back on that one Chris.

I have experienced these demos and not been bothered by any noxious odours so I guess they were all using odour-free material in contrast to a sample A4 sheet from another company sent in the post which contaminated my office for weeks!! I dread to think what that must have been like when it was being engraved!! There's nothing like the smell of burning rubber - but I prefer it from my car tyres!!!

I guess what I really need to know is the question of resolution and spot size. The Galvo is quoted at 300 x 300 which, to me seems like a pretty reasonable working area, and if you check here http://www.shertec.com/technology/Laser-Technology/Galvo_Technology (thanks to Dave) they uses a special lens which maintains a perpendicular beam over that area. I initially thought that there would be a tendency for the spot to go elliptical as it moved away from the centre but apparently not.

I have been in contact with a Chinese producer who has offered an incredible deal which I won't post at this stage as they are in the process of preparing video of the machine in action on rubber. They have sent one through but I didn't make it exactly clear how things were supposed to be (my first experience of Chinelish so I wasn't sure quite how to write but I'm learning quickly). It shows promise and if I can remotely fine-tune the settings, we maybe onto a winner.

I'll post some more when I have something positive to report (or the opposite if it transpires that is the case).

Anyhow I think I've thrown sufficient fat onto the fire for now - thanks again guys and this time I've cut and pasted it into Word so if it bombs I still have it!! I should have done in Word first and cust and pasted it into here - you live and learn!!:)

Bob Nolaser:(

Dan Hintz
10-10-2013, 3:58 PM
Bob,

If you're not using your laser at 100S and less than max power, I would agree that going with the Trotec is probably not your best deal... if you are maxing out your speed, that Trotec could very easily pay for itself pretty quickly with the extra speed it offers. Consider upping your wattage by 25% and the extra speed may prove quite useful.

For the galvo, final spot size is determined by the working area of the lens. Most setups come with an F-theta lens that simplifies the calculations necessary internally to mark a specific point. The lens you're talking about (perpendicular beam) sounds like a telecentric lens... they're usually used for drilling type operations where you want/need a beam incidence as perpendicular as you can get to the substrate. Most work you do (even stamps) can get away without that, unless you're going really deep.

matthew knott
10-10-2013, 5:38 PM
Dan is right a telecentric lens is total overkill for rubber stamps, they are not cheap either, 300 x 300 is a long lens for co2 marker, that will mean a big size, i would estimate about .3mm (lots of factors than can effect this though). Also as rubber stamps are mostly engraved in relief, this means that much of the speed advantage of a galvo is lost as there are a lot less jumps to do. Chinese machines can be great but support can be at best patchy, if you're prepared to put the effort in they can represent great value for money. Oh, one other thing, speed is good but if you can get your daily work done in 2 hours on a fast machine, does it matter if it takes 4 on a slow one, bear that in mind. Lots of people in the UK importing cheap chinese lasers, and support is available, I have one and ive been very happy with it, shame your 2.5 hours away, we have pretty much every laser under the sun here so you could have a play with them and see the difference between a cheap chinese to a western galvo co2

Bill Cunningham
10-10-2013, 9:25 PM
One of the reasons I originally bought a laser was to make rubber stamps. I do use 'rubber' the odd time, but only for stamps that use oil or acid based inks. Most standard stamps require only water based ink, and polymer works perfectly. No stink, and can be washed up with water and a brush. I make my own polymer engraving sheets using liquid polymer from millennium marking. I also make wholesale dies for other stamp sellers that buy the self inking units, but have no means of making the imprint dies. They just stick em on and sell the stamp.

Mary Geitz
10-16-2013, 12:07 PM
Has anyone made artistic rubber/photopolymer stamps or are you just making address stamps for the hand held inker?

Gene Howard
10-17-2013, 8:52 AM
Has anyone made artistic rubber/photopolymer stamps or are you just making address stamps for the hand held inker?

We make everything from self-inking address stamps to government process stamps to scrap-booking art mounted stamps and everything in between. We use the same rubber for all of them, the Classico in red from Trodat USA. It's a nitrile rubber that stinks to high heaven but lasers nicely and cleans up well with laundry detergent and warm water.

Bill Cunningham
10-17-2013, 8:19 PM
Has anyone made artistic rubber/photopolymer stamps or are you just making address stamps for the hand held inker?

Yup I make all kinds of 'art' type stamps. Polymer will etch just as good as rubber, but without the 'Roaming skunk' smell..
Left is the polymer, right is the imprint..Even this small it holds good detail
273172

Dan Hintz
10-17-2013, 8:28 PM
Were you trying to get the picture 1:1 scale with the stamp, Bill? ;) It's tiny!

Bill Cunningham
10-17-2013, 8:50 PM
Were you trying to get the picture 1:1 scale with the stamp, Bill? ;) It's tiny!

Yup that stamp is about .75" high

Robert C Kelly
10-23-2013, 10:47 AM
Dan is right a telecentric lens is total overkill for rubber stamps, they are not cheap either, 300 x 300 is a long lens for co2 marker, that will mean a big size, i would estimate about .3mm (lots of factors than can effect this though). Also as rubber stamps are mostly engraved in relief, this means that much of the speed advantage of a galvo is lost as there are a lot less jumps to do. Chinese machines can be great but support can be at best patchy, if you're prepared to put the effort in they can represent great value for money. Oh, one other thing, speed is good but if you can get your daily work done in 2 hours on a fast machine, does it matter if it takes 4 on a slow one, bear that in mind. Lots of people in the UK importing cheap chinese lasers, and support is available, I have one and ive been very happy with it, shame your 2.5 hours away, we have pretty much every laser under the sun here so you could have a play with them and see the difference between a cheap chinese to a western galvo co2

Thanks for the offer Matthew, I've already traveled twice to Tamworth and Northampton, also done Birmingham and Leamington so distance is not a problem, I've had loads of communication with Dave and spent a day with him - which was really informative but my brain got fried along with the lasering :)

I'm up to my eyes (as I'm sure you are too) but I'd really like to get up and take advantage of your hospitality - I'll try and call you sometime - Thanks