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View Full Version : Preparing sandblasting stencils with an epilog laser



Zeev Goldin
03-11-2008, 8:34 PM
Hello nice people of the Creek I am coming to you with a question...again.

So I need to set up a sand blasting machine in order to do quite a bit of carving jobs on glass bottles (tried the laser but the client thought that it is not deep enough) so I have to try to sandblasting . This is potentially a job that will be a come back potential.
So what I need is a way to make stencils in order to sandblast the designs and text on the bottles mostly it will be text and small logos(the size of the stencil will usually be 6" wide on 4" of the ).
The problems that I have is:
1. I will need to mass produce/sandblast those bottles, potentially 1000-2000 a month. So I need to find a stencil material that could be reusable (other words I can use it instead of 1 bottle and throw away-as many bottles as possible and then throw away). Probably some harder material(my logic tells me) instead of the regular soft material a lot of companies sell specially for sandblasting.
2. The second problem is I would really like to be able to cut the stencils with my laser machine(I know that a lot of materials contain PVC).
3.Any kind of advice for making the process easier or more efficient is welcomed.

Dose anybody has some experience with such jobs ANY advice will help.

Thank you all sincerely. ZEEV

Bill Cunningham
03-11-2008, 8:54 PM
Being new to sandblasting myself, I would go for a re-usable stencil, mabe made out of sign magnetic.. It's thin enough to keep detail, and thick enough to be re-used over and over .. Just wrap it around the bottle, and tape in place. Haven't tried it myself, but I can't see why it would not work

Mike Null
03-11-2008, 9:10 PM
I would think that sandblasting will be too expensive considering the volume you want to do. I am only guessing, but I imagine that your customer is looking to pay a dollar or two at most given the volume you mentioned.

I would think a photo-resist with a chemical etch would be more economical.

Joe Pelonio
03-11-2008, 9:28 PM
I would think that sandblasting will be too expensive considering the volume you want to do. I am only guessing, but I imagine that your customer is looking to pay a dollar or two at most given the volume you mentioned.

I would think a photo-resist with a chemical etch would be more economical.
I'll second that.

The magnetic material is not going to be flexible enough to lay down without being glued on, same for any other materials that will last more than one use.
The problem is that if it's not down tight the sand will blast around the edges and ruin the image. You can cut a lot of stencils with adhesive rubber sandblast mask on the laser, but then you have to weed it too. Lots of time ($). Explain the costs to your customer, the laser may not be "deep enough" but will cost a lot less.

Zeev Goldin
03-11-2008, 9:57 PM
To Joe

I tried the problem is that he NEEDS it to be carved otherwise he will continue to print on the bottles. No point for him to do regular etching with the laser.

So what you people are saying is that there is no way to do this?

Thanks

Joe Hubbard
03-11-2008, 10:08 PM
I get to do quite a bit of sandblasting and as much as I'd like a reusable resist - I'm not aware of any such product. In order for graphics and lettering to be crisp and carved deep enough to give that "quality" look you really only have two choices. Photo resist is an option because you can make up a bunch ahead of time. The problem is that photo resist is quite spendy and you need additional equipment to create/process/dry the material. Then the best way would be to create a jig so alignment is always in register. The second option is to use laser tape or laser resist which works great as long as you don't blast over about 25-30 psi. Cost is slightly less but set up becomes an issue because you have to (on bottles at least) run it with your rotary fixture one at a time. Either way I'd blast with 220 Silicon Carbide at about 25 psi and depending on the complexity of the image plan on 10 - 15 minutes/bottle. If you were set up to blast one after another you could cut this down but remember to mask every part of the bottle not covered by the resist - the Silicon Carbide has a tendency to bounce about and etch or frost anything not protected - so masking/unmasking/cleaning adds time to the job. Even best case - you probably can't do more than 10 bottles/hour so figure your cost that way. I do agree that sandblasted glass looks far superior to laser but much more time involved. Joe

Jim Huston
03-12-2008, 6:32 AM
Pre made stencils to your specs are avaible from the photo mask suppliers. They come already exposed and washed out - all you have to do is peel and stick. Only way to do high volume jobs at a reasonable rate that I know of.

Doug Griffith
03-12-2008, 9:56 AM
I too have created sand blast friskets but used a vinyl cutter (with pounce). The cutting is very fast, the weeding is very slow, and application can be a pain because you need to use transfer paper. Whatever sand blast method you use will take quite some time per bottle.

Roy Brewer
03-12-2008, 1:42 PM
So what you people are saying is that there is no way to do this?
Yes,
That's what we're saying. If you want the job, don't plan on burning the resists with your laser; that's not to say you can't do it, but it is impractical.

We assume these are not personalized or else your client would not be screen printing them currently. If that's the case, buy your masks in bulk from the sand carving suppliers who offer that service.

If personalizing them is what you need, with a photo/emulsion system you could do 5-8 times the masks in the same amount of time you'd be lasering one.

Hilton Lister
03-14-2008, 12:40 AM
I would cut masks with vinyl cutter. Apply, THEN weed out. Took me years to work that out!
If you make the masks oversize, you can then use a piece of rubber sheet with a hole less than the mask size, wrap the article you are blasting, leaving the vinyl mask exposed, then blast away. Still somewhat time consuming, but the results are excellent.

Gary Hair
03-14-2008, 12:35 PM
What kind of price are you getting for these bottles? If the customer is going for the cheapest option then sandcarving may not be it unless you subcontract them out to someone who does automated blasting. I would never consider doing 1,000 - 2,000 bottles a month unless I was either getting $8-$10 each or subbed them out to net $1/$2 each.

Just my .02

Gary

Paul Brinkmeyer
03-18-2008, 6:20 PM
I have an opportunity to sandblast some pavers. I have never tried pavers before, so I have a question. What mask should I use for this? Hopefully one I can cut on a laser as I do not have a cutter. Any other help/hints will be appreciated.

Roy Brewer
03-19-2008, 1:08 AM
I have never tried pavers before, What mask should I use for this? Paul,
Most of the huge signmaking supply companies including http://www.Reecesupply.com carry a selection of tough masks for signmakers(sandcarving "redwood" type signs) and many also use that mask for pavers. Most I see doing this vector cut the mask and then weed it; takes to long to raster completely through it.

Also, any of the guys that sell sand carving machines including http://www.rayzist.com not only have masking materials but are typically more helpful about using the masks than the signmaker supplies guys.