Masonry Thimble Adapter?

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Hexa Fox

Member
Sep 19, 2023
187
West Virginia
Hey guys,

So I just bought the following product and I am confused. First off the outer diameter of the flange/thimble cover is larger than advertised. It clearly says 10" and it is easily 12". For me 10" would have been perfect because it would have fit snugly against my thimble and the cut out portion the the brick. Now if I am going to use it I have no choice but to install it by drilling into the brick on my hearth.

I'm not totally against that but the holes on the flange are very small and right on the edge of the flange. They are also angled because the flange is at an angle. I was hoping here someone had some advice for me. I am using Double Wall stove pipe to connect to my tee for my stainless liner. So this adapter would or possibly still could be perfect.

Hope all you guys are doing well and enjoying the Christmas/Holiday Season!

 
Can someone here tell me if it is possible to trim the flange/thimble cover of the above connector? If this was just a half inch shorter in diameter it would fit snugly against my thimble connection where I could screw it or seal it on to secure it. I am seriously considering trimming it but obviously cannot return it after doing so.
 
It may be ok to trim it as long as combustibles are not too close. Got a picture of the thimble that shows the issue?
 
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It may be ok to trim it as long as combustibles are not too close. Got a picture of the thimble that shows the issue?
As always thanks for stopping by begreen. My project is coming along. I got all the stuff installed down the chimney and now only need to connect the wood stove to the tee. I ordered stuff that I hoped would work.

Anyway, I ended up ordering two double wall thimble adapters in hopes that one would work. The issue here is that the edges of the flange just barley start to go over the brick hearth. Specifically, if I were to drill into the hearth to place anchors I am very close to the edge. The Selkirk one looks like it may be possible to install but as I said it just barley catches a brick on each side. So my idea was to trim some off of the second one (as the flange is smaller) so it will fit flush in this recess and then possibly silicone it.

I hope the pictures make sense. The actual pipe of the adapter is sitting on the masonry thimble. So if I were to raise each of these up you can see they are not covering a lot of the hearth to have a great anchor point.
Masonry Thimble Adapter?Masonry Thimble Adapter?
 
By trim, do you mean to shorten it by cutting off some of the tail end in the thimble? Does the liner's tee snout insert fully into the adapter?
 
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By trim, do you mean to shorten it by cutting off some of the tail end in the thimble? Does the liner's tee snout insert fully into the adapter?
No, I mean the decorative collar/flange that covers the hearth. Sorry I am having trouble describing it. You are suppose to drill into the hearth and anchor the outer collar to your hearth. This is a difficult install for me because this outer collar does not cover a lot of the brick. Meaning my holes are going to pretty much be on the edges of the brick you see. The second some is smaller so I am thinking about taking a half inch or so off the entire outer diameter so it will just fall into the hole you see and fit snugly against the thimble. I'm not sure I can perfectly cut it either.

To answer your second question, no it does not. I will have to use a telescoping piece of pipe (that I have) to bridge the gap. My main reason for doing all this is I want to look decent and I want this pipe to be supported and not pulling down on the tee's snout.
 
Got it, sorry for the extra questions, but amazingly I did recall an issue with the tee snout length. I just wasn't sure it was this install.

Is this an 8" thimble? The adapter looks like it's sitting low in the thimble. There is more thimble showing at the top and none at the bottom. Would this be correctable by shimming under the bottom of the adapter in the thimble? Or would that not be enough to cover fully cover the rough edge of thimble? I ask because it will be hard to trim that flange evenly unless one is pretty skilled at sheetmetal work. Can be done, but it will take some experience. Another option might be to add a trim collar around the adapter pipe between the flange and the brick.

I'm not sure if this one would fit but it shows the general idea.
 
Got it, sorry for the extra questions, but amazingly I did recall an issue with the tee snout length. I just wasn't sure it was this install.

Is this an 8" thimble? The adapter looks like it's sitting low in the thimble. There is more thimble showing at the top and none at the bottom. Would this be correctable by shimming under the bottom of the adapter in the thimble? Or would that not be enough to cover fully cover the rough edge of thimble? I ask because it will be hard to trim that flange evenly unless one is pretty skilled at sheetmetal work. Can be done, but it will take some experience. Another option might be to add a trim collar around the adapter pipe between the flange and the brick.

I'm not sure if this one would fit but it shows the general idea.
I have cut a lot of metal and have plenty of experience. However, with all that experience I have never in my life been able to cut metal straight lol. Therefore maybe I should avoid it, since my goal is for it to look good.

Ask as many questions as you want, it is you trying to help me and in my best interest to make certain you know what is going on. I appreciate the feedback. So both of the things you are recalling are probably me so good memory you have. Yes, it is an 8" thimble and yes it is an awkward length of run. 2' length of pipe is just a little too much and 1' of pipe with a telescoping adapter is just short.

The main reason for wanting to get one of these to work is it is basically an adapter for double wall from the stove and single wall to the tee. If I use the one I got from DuraLiner I will need another adapter for the wall so that the double wall stove pipe will work.

Shaving some off the bottom like you mentioned will not help me either. I need the entire outside diameter reduced so it will fit. I just laid the pipe down inside the thimble so you could get an idea. Like I was saying the Selkirk one does hit brick on all the screw holes but it is just barley. So the hole that will provide the anchor is going to be very close to where the thimble opens up and I do not particularly like that.