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FAQs
My PrecisionMasks are all stuck together.
- Always store PrecisionMasks in cool, dry place with sheets of paper interleaved between them.
I can't tell which side up my PrecisionMask should be applied to the glass - both sides look the same.
- In future, make sure a little R is included in every artwork, to indicate the right-reading side of the PrecisionMask. For now, wet the mask for a moment or two in the diluted Adhesive - the mask edges will start to curl away from the side that should be applied to the glass.
My PrecisionMask curls up at the edges when I try to stick it on the glass.
- In future, make sure that you leave the 2mm border of clear Carrier Film, supplied around the edge of each mask, attached to the mask. The surface tension underneath this border will be sufficient to hold the edges down. For now, press the curling edges down firmly with your finger as the mask starts to dry, until they stay down.
I can't get my PrecisionMasks to stretch around compound curves.
- Warm the glue and/or the glass slightly, this will make the masks easier to stretch.
My PrecisionMasks distort when I'm squeegeeing them down.
- There are three possible causes of this:-
- The squeegee was dry when squeegeeing the glue from behind the mask and has snagged the surface. Always wet your squeegee with the dilute Adhesive.
- The mask was repositioned but part of it had already stuck down.
- The glue and or glass are too warm - cool them down a little.
In all cases, if a mask has become a little distorted during application, it can often be rescued by removing it from the glass and laying it upside down for a minute or two to allow it to regain its shape - gentle warming may help.
Bubbles appear behind the PrecisionMask whilst it is drying.
- There are two possible causes of this:-
- Bubbles in the glue were not squeegeed out from behind the mask. Be more careful and check the back of the mask through the glass after squeegeeing - if you do spot some at this stage, you can peel the mask off and re-apply it.
- The mask on the glass was dried at too high a temperature and water vapour from the drying adhesive has created bubbles under the mask, rather than permeating out through it. If these bubbles are outside the detail, mask them before blasting. If they are within the detail, wash the mask off and start again. Lowering the drying temperature will prevent this in the future.
Some of the detail comes away with the Carrier Film when I peel it off the glass.
- There are two main causes of this:-
- By far the most common problem is the adhesive not being dried properly or for long enough. Many factors can affect the drying time - Too much adhesive left behind the mask (squeegee more carefully and firmly); Ambient temperature too low (warming in an oven at 45 - 48C is ideal); Moist atmosphere (again, warming in an oven at 45 - 48C is ideal).
- Occasionally, the glass surface may be greasy or contaminated with detergent or rinse aid. Wash the glass with an alkali such as Mangers Sugar Soap or a 10% solution of caustic soda. N.B. PrecisionMask Water Based Adhesive does not adhere well to heat treated glasses, such as Pyrex, which have a different surface chemical structure to ordinary glass.
The stencil film comes completely off the glass when the Carrier Film is peeled.
- See the previous answers or, more likely:-
- The mask was applied inside out. Re-apply it the right side out.
My masks are wearing through before I can engrave any depth.
- Part 1 The masks are pale blue:
This will be a halftone or equivalently fine detail mask, in which case you will neither wish to, nor be able to, engrave to any depth.
- Part 2 The masks are bright blue, but they are still wearing through:
This will be a combination of one or more of the following factors:-
- Grit size. Use 320 grit or finer.
- Grit aggression. Some new grits are extremely sharp to start with. Use a reduced pressure and increased care when operating with brand new grit. We advise recycling grit and regularly mixing a little new in with the old, rather than wearing it out completely and changing the whole lot at once. N.B. Worn grit will actually allow you to achieve a deeper cut. It still shatters the glass almost as well as new grit, but it doesn't wear the mask away nearly as quickly. Thus allowing a deeper cut.
- Nozzle size and air pressure. Reduce them both until you get the results that you want.
I'm getting a speckled or frosted effect around my engraving.
- This indicates sharp new grit at too high a pressure for the mask, particularly with halftone masks. Reduce the pressure until your grit has worn a little.
I'm getting holes suddenly appearing in the mask when I'm sandblasting.
- This is caused by air bubbles under the mask, which burst when they are blasted. See the section above on avoiding bubbles.
Little bits of detail fly off when I'm sandblasting.
- The glass surface may have been greasy or contaminated with detergent or rinse aid before the mask was applied. This tends to happen only with certain glasses from certain manufacturers (most can be used straight from the box without problem). It can be avoided by washing the glass beforehand with an alkali soap, such as Mangers Sugar Soap or a 10% solution of caustic soda. N.B. PrecisionMask water based adhesive does not adhere well to heat treated glasses, such as Pyrex, which have a different surface chemical structure to ordinary glass.
My halftone engravings are stripy or banded.
- This is caused by uneven blasting. Rather than trying to achieve a close, accurate blasting in one or two slow passes along close parallel lines, blast from further away, at a lower than normal pressure, using a multiple series of light passes - thus dusting the surface evenly.
My halftone engravings are indistinct.
- Halftone engravings are necessarily very shallow. Any attempt to blast depth will preferentially wear away the smaller dots and will also produce tiny sides to the cuts, which will pick up and reflect extra light. Both of which will upset the balance of the halftone image so carefully prepared in the original artwork. Do not attempt to engrave to any depth.
I'm getting a thin engraved line appearing at the joint of my Continuous PrecisionMasks.
- This is caused by a bubble creeping along the joint as the adhesive dries out, which then bursts as it is engraved. The dabs of Carrier Film at D and E as described in the instructions, help to stop this, as does the zigzag Z in the artwork. If it still appears, despite these precautions (and if it does, it can be seen from the back in reflected light before being blasted), then mask over it.
My Intaglio engravings are flat, with no 3D effect.
- Two possibilities could cause this:-
- Too coarse a grit. Intaglio engraving will only work when using fine grit (preferably 400 grade plus, to dust) which has been well worn. The more worn the grit, the better the intaglio results. Use a new or a coarse grit and the mask will wear away far too quickly and the different depths will not be created in the glass. The mask should be seen to wear away gradually as the engraving progresses.
- Under or over polishing after the engraving. We recommend a cork wheel with pumice medium and a light polish, just sufficient to pick out the highlights.
None of the above?
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