Drilling Fire Brick

[danno]

I'm rebuilding my grates out of fire brick. Any idea how easy/hard it is to drill fire brick. I've cut fire brick pretty easily over the years to brick a few different arches, but have never drilled the stuff.

I'm looking to drill 3/4" or 1" inch holes with a mason bit to allow some of the ash to fall through, and more importantly, to allow some forced air to come up through.

Any of you guys that have done this, were you able to find pre driiled brick, or did you have to drill it yourself?

[ericjeeper]

why not just use a House brick with holes already in it? They won't last as long, but they are cheap usually.

[Haynes Forest Products]

The slightly yellow fire brick drills like butter. Dont use the hammer drill option because that will cause cracking. H D has hole saws for tile and they will get you a bigger hole. If dust is a problem use a cordless drill and sublerg the brick in a bucket of water and drill the holes. When you drill as soon as the bit shows thru the backside stop and drill from the oposite side it wont blow out on you. Nice neat holes.

[WF MASON]

When I drill them I use a 3/4" cement bit and haul the drill press outside, I made a jig to clamp to the table and slide them along , 1,2,3 , makes it go faster.

[danno]

Thanks guys.

What do you use to support the bricks - when using them as grates. I'm thinking steel mesh. It obviously can't be sheet metal - cause I need air to pass through and ash to fall through.

Do the holes in the brick plug right up with ash?

[Bucket Head]

Yes, what do you use for support?

How many 3/4 holes per brick?

Full or half brick?

Also, out of curiosity, why are there two sizes of fire brick? Where would you want to use a thin one over a thick one, and vice-versa?

Steve

[mfchef54]

my evaporator has three sets of angle iron for the bricks to fit on. I'm using regular bricks with holes, (like the original owner) . after the first three firings the middle brick broke and I just replaced it. the ash just falls through (what little there is left) Using a blower helps. I think the air flow is good. the original owner said that he was getting 10/hr, with the blower I'm getting18-20