Masking Technique Recommendations?

[adana]

Hi all,

I've been doing some work for a new customer that involves some complicated masking shapes: patterns on longboard decks, kinda fun. I got excited when I learned I could apply Oramask to the workpiece (baltic birch ply), then cut the masking in place using the Cricut drag knife (see other thread). Peel away the unwanted parts, burnish the edges of the remaining masking, and voila! Ready for staining (dye, actually, for reduced bleed) and finishing.

But there are problems:

1. workpiece flatness: the Cricut knife isn't spring loaded and doesn't tolerate a lot of Z variation on the workpiece. I'm not currently using vacuum holddown, but I intend to be soon. Hopefully that will help hold the wood flatter?

2. grain tearing: the Oramask is pretty sticky, and develops a stronger grip the longer it's been on the wood. I'm handing these parts off to someone else for finishing, so it's sometimes a couple of weeks before they get sprayed and the masking is removed. The birch is especially bad about having long threads torn away at this point. It doesn't look good at all.

So, solutions...

- Should I cut the masking separately, directly on my sacrificial board, and then apply it with some kind of a transfer? But these are large parts - 48" x 15" - and I wonder how accurately the masking could be applied. Even 1/16" off would look crummy.

- Are there masking products that will tear the birch less, and be okay when left on the wood for a week or more? And, optimally, less expensive? That stuff is pricey but comes well-recommended from this or the Vectric forum, I forget.

- Is there a surface pre-treatment that will reduce the tendency to tear while still letting the dye work? I'd rather not have to do something like this.

This is a new thing for me; any advice would be awesome.

Thanks,

Adan

[donek]

Tape adhesives will normally begin to loose strength at higher temps. You could try a heat gun, or better yet an oven to bring the parts up to 160 to 180 deg F. Such an oven could be made from light bulbs in an insulated box.

Drag knife applications will be extremely sensitive to material flatness. It is frequently important to surface your table frequently to ensure it is true to the spindle. Vacuum hold down is very important. That being said a vinyl plotter can be obtained for very little these days ($250 for 31in width on amazon) and cuts vinyl more efficiently than a cnc router. Signs like this are applied with a transfer tape, so it is very easy to locate accutately without different components moving. Stencil materials are available as well.

[jerry_stanek]

The widgetworks unlimited drag knife is spring loaded to compensate for the uneven surface.

[adana]

Wow! I had no idea a vinyl cutter could be so cheap. Goodness. Very good thing to keep in mind, thanks.

I'm thinking I'll give it another shot cutting on the board itself, then try the heat-to-remove suggestion. That sounds like it might well help.

I was trying to avoid buying the Widgetworks swivel knife, since it's so much more expensive than the Cricut thingy and that already works very well.... but sometimes ya gotta spend the extra dollar to get the last bit of functionality, I guess. I'll give the Cricut thing one more chance.

Thanks for the suggestions, all.

[adana]

Thanks again for everyone's advice... I ended up getting the WidgetWorks knife and indeed the spring loaded functionality made it much more effective for my application than the Cricut bladeholder. Oh yeah, that and the fact that the blade didn't fall out every time the machine pulled up from the surface!

I just saw the Donek drag knife this morning... pretty cool! I would have been very torn if I'd seen it earlier: it has some key advantages over the WW knife.