# PolyFiber minimums

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#### KWK

##### Well-Known Member
HBA Supporter
The PolyFiber book mentions 3 PolyTone colors can be used without PolySpray beneath, just a single layer of PolyBrush. All 3 are metallic, one blue and two silver. Are these difficult to spray evenly? I wrote to PolyFiber but they are mum.

I also wonder how it would end up with no PolySpray to sand smooth, but the book mentions PolyBrush can be smoothed with an iron.

One PolyBrush, smooth with iron, 3 PolyTone layers, done. Sounds like a savings in time, effort, money, and weight. There must be a catch (which is why I'm buying their Practice Kit).

#### Turd Ferguson

##### Well-Known Member
I don't think you'll be happy putting paint, or polytone over brushed on polybrush.

You can reduce polybrush and spray it. It comes out smooth - no bumps to show through the finish.

#### TFF

##### Well-Known Member
Normally it’s 3,3, and 3. First coat of poly brush by brush then two sprayed. Then others sprayed. If you try to brush the stuff with any below, it leaves brush marks. First coat brushed is to get the stuff to wrap around the threads to lock it on.

#### Dan Thomas

##### Well-Known Member
Normally it’s 3,3, and 3. First coat of poly brush by brush then two sprayed. Then others sprayed. If you try to brush the stuff with any below, it leaves brush marks. First coat brushed is to get the stuff to wrap around the threads to lock it on.
Yup. One brushed coat isn't nearly enough buildup.

#### TFF

##### Well-Known Member
Most of this paint is solvent. Not necessarily hard to paint but it is not modern car paint. It’s easier than dope, but more dope like which is a version of lacquer.

#### KWK

##### Well-Known Member
HBA Supporter
... poly brush stuck to the iron... gets burned on...
At about what temperature should I worry about burning on? For the flattening process, they recommend 200 to 225 F.

#### Dan Thomas

##### Well-Known Member
If you take a closer look at the roll of picked tape, you see that the pinks get bent outward toward the outside of the roll. That's from the tightness of the rolling, and setting the roll on its end also seems to bend them outward. Now, if you lay that tape down on the fabric the same way you would use a tape dispenser and packaging tape, the pinks are already wanting to stand up. Turn the roll over and lay the tape down that way, as if you were unrolling carpet on a floor. Pinks are bent down and will stay down.

The other secret is to do it exactly as the book tells you. Paint a strip of Poly Brush along the place the tape will lay and let it set. Then lay down the tape and brush Poly Brush through it. It will dissolve the previous layer and that alone will absorb much of the solvent and stiffen the Poly Brush immediately, making it less likely that pinks will stand up.

I never had to iron pinks down. Follow that manual.

#### Fiberglassworker

##### Member
One method of dealing with PolyBrush sticking to the iron when blending the edges of pinked tape, is to use a layer of Teflon coated fiberglass cloth between the iron and the Polybrush. Iron the pinked tape down with the Teflon tape between it and the iron, wait for the polybrush to cool then lift the Teflon tape off. I find a model Airplane Monocoat iron best for this.

#### PTAirco

##### Well-Known Member
Hmmm, I had the impression everything in the PolyFiber process dissolved in MEK. Good to learn it's not so, before getting in to trouble.
It does dissolve with MEK. Every Polyfiber product does. Right down to nothing. Read the manual. Six times.