Hole strategy

[David Russell]

I was wondering what methods are used by people to get the right placement for the holes one cuts in the frax to place the passage brick/element. I have tried eyeballing it, not so great results. Last time I measured out spacing before laying the frax and that worked alright. Right now I am trying a template out of poster board that is marked before the frax goes on. What has worked for you?

[Rick Kellner]

I wonder if this is the type of scenario where you could get away with employing a trick of the upholstery trade.

What about laying your frax over the top, then poking something like an upholstery "regulator" (basically a giant needle like thing) up through the center of the passages from the bottom? As the needle pokes through the frax up top, you simply mark the points of penetration, then plan your passage cuts based on these markings.

[Eric Trulson]

I've always just done it in situ (pretty much how Rick describes, except I do everything from the top).

Cut the whole piece of frax so it fits cleanly and lay it flat on top of the furnace. For each passage brick hole, press down with your hand (on top of the frax) in the general area until you find the hole, then press around the edges to leave a slight indentation in the shape of the passage brick hole.

Take a utility knife and cut an "X" in the frax, going corner to corner in the indentation you just made. Once the "X" is cut in, you can pull up the little triangles of frax to see the hole clearly, and cut the frax to match the passage brick side walls.

[Sky Campbell]

Wow you guys all go for one piece? I prefer the multi layer tear, rip, cram pack and tuck strategy.. If it ain't broken give me some time and I'll fix that.

[Brian Graham]

I created a cardboard template the last time I had to do it. I like to use a long and skinny kitchen knife to cut the frax. I picked up a used Chicago Cutlery knife at the thrift store....works great!

[Pete VanderLaan]

I'm with Sky. Cross hatch the thing. Keep it tight in the layers. 2 " thick 8 lb density fiber.

[David Hopman]

An electric knife is wonderful for cutting fiber. Check thrift stores, I've never had to pay over $5 for one.