Venting and Insert Stove up chimney

[Hammer]

I have read and read and re-read anything I can find on the net about venting up past the smoke shelf in an existing chimney and still have questions. I am hoping the answers will show up here. I know that the 4" stainless pipe needs to be flattened to get past the damper IF the damper can't be dismantled. I also know that a dust shield needs to be installed with insulation on top of the sheetmetal and possibly caulked.

Question: How do you hold the dust shield in place? I was going to make a cardboard template and then cut the sheetmetal, glue the insulation on top of the cover, slide it in place and have four pins (bolts perhaps) slide into the bricks in 4 spots UNDER the shield to hold it in place. Think that might work?

Thanks
John

 

[DiggerJim]

I posted something a week or so ago about how to make the plate that you're referring to as the "dust shield" It's more than that - provides a positive flue connection in the chimney and prevents dilution of air into the combustion stream. I don't think you want to try flattening the vent pipe. I had to cut the damper rod with a Sawzall in order to get mine out (I can always weld another one to the stub I left if I want to convert back to a standard fireplace). Could have used a hacksaw or Dremel to cut the rod but I like using the Sawzall

 

[tonyd]

I used two pieces of sheet metal. After pre-drilling over sized holes in the flange that the damper use to rest on, I attached one piece that didn't have the hole using self tapping screws (Through the flange and into the sheet-metal).. Reaching on top of the sheet metal to hold it down while attaching. Put the second piece in, with the hole, and attach using the hole to reach into to hold down to run the screws.. Seal and insulate USE SAFETY GLASSES FROM THE FIRST LOOK UP. So far so good.