Chimney plate question

[Salv B]

Hi all,

I am in the process of fixing a stainless steel chimney plate to the vent arch and have struck a small problem. I have read in a number of threads that tapcon screws were recommended for doing this. I managed to get some tapcon screws but ended up stupidly drilling holes in the firebrick that were too large for the screws and I cant get larger tapcon screws from any supplier here in Adelaide. My question is does anybody know whether dynabolts are ok to use? Or does anybody have an alternative way to fix this problem. My other option is to backfill the holes with high temp mortar and then place the screws in and let the mortar set. Any views would be much appreciated.

Cheers

Salv

[dmun]

Re: Chimney plate question

The old guys just hammered lead slugs into the holes and used ordinary woodscrews to attach things. If you roll up a sleeve of lead flashing for this purpose, you get a pilot hole in the center already.

[philldresser]

Re: Chimney plate question

Can you not create a new set of holes in the plate and brick?

[glennb]

Re: Chimney plate question

I reckon the high temp mortar will do a fine job of holding them down, otherwise the dynabolts would also work. They are only holding down the plate when/if there is any load (from wind i guess) on the chimney, otherwise they are not really doing anything structural.

[Benny]

Re: Chimney plate question

Hi Salv,

I agree with glennb; high temp mortar should work well if it is just to stop movement. Depending on the strength of your fire bricks dyna bolts may crack them if you try to tighten them too much; but if pinched tight they should work fine also. Good luck, let us know how you get on. I'm not up to that point yet so am very interested.

Benny

[Salv B]

Re: Chimney plate question

Thanks everyone for the advice.

I was looking at drilling new holes as a last resort - the bricks the chimney plate sits on are mortared to the vent arch and I didn't want to run the risk of the bricks cracking.

As Benny mentioned I am also worried that using Dynabolts will crack the bricks so at this stage I am leaning towards backfilling with mortar. Although I do like Dmun's suggestions of using lead slugs, however this is a new technique to me and am not too sure how it works.

Will post some details once I decide what to do - I'm presently doing more fun things - curing fires!

cheers

Salv