Mini Stove > Cabin job.

[zoothorn]

19 hours ago, PeterW said:

Top of the stove pipe into the twin wall should be a tight fit with no sealant needed. Got a photo ..? 
 

Once twin wall is tightened up with the bands it is rock solid. 

Hi Peter,

 

it's not at all this seems the problem. Ive got another 4mm gap ( 2mm all around the adaptor's downward male end) here. There is no band tightening these two, because the outer layer here is the very solid single enamel flue. So, how I join these two.. I really don't know tbh.

 

The only thing I can think of to do, is add a wadge of cement  around the adaptor, like a ring around the uppermost part of the downward end... then just sit the heavy twinwall sections onto the single & let gravity do the seal aided maybe by the cement, but not very well surely, & will just crack & fall out soon. But I cannot see.

 

The three silver twin bits, adaptor/ 1m/ hat, do join together fine with supplied two bands.

 

A photo I don't think can help as the single just covers over the adaptor, outside of it.

 

I spent ages on call after call to get certainty these 4 bits would fit together, buying all from the same place, costing me a fair bit more to source from one supplier. Hmm.

 

Zoot.

[zoothorn]

@PeterW

 

Just to reitterate.
 

I bought a single flue diameter 4", 1m length, going into the stove ( fits, but loosely, a 4mm gap here).

 

Then an adaptor to twin wall. Then a 1m twin wall. Hat.

 

It seems the single length is too narrow at the (lower end) male end. And it seems either it's other female end (higher end) is too wide..

 

.. or the adaptor's ( into which its top end fits around) lower male end is too narrow.

 

But I just don't know what to expect/ what is normal/ whether these fitting together are all fine, or totally not fine at all.

 

Zoot

[zoothorn]

Its A) and B) points the issue. Specifically B) because I cannot see what's going on, as I can with A).

[Conjecture: even slight movement of the chimney above join B) will compromise whatever is used to help this join here. Less movement at A) & if the cement does fail here with say a tiny bit of chimney movement, I can visually see > re-cement.]
 

All 3 twin sections above B), clamp together just fine.

 

Thanks zoot.

[PeterW]

2 hours ago, zoothorn said:

bought a single flue diameter 4", 1m length, going into the stove ( fits, but loosely, a 4mm gap here).

@zoothorn can you post a link / pic of the enamel pipe ..? I think it’s got male / female ends so using fire cement or HT sealant will be fine. But need to see first 

[zoothorn]

3 hours ago, PeterW said:

@zoothorn can you post a link / pic of the enamel pipe ..? I think it’s got male / female ends so using fire cement or HT sealant will be fine. But need to see first 

Hi Peter. Yes it has the shaped 'male' lower end, I sort of tried to draw this narrowing of it at A). But it's just either slightly too narrow (the dip in/ shaped end almost dips in a bit ott)... or of course, this is fine but my stove hole is judt slightly too big/ too "safely made".

 

Im just in no position to know which it might be, nor whether either is in fact problematic at all. As I have no reference to look at. It could be that each is as should be, & the cement makes it a 'tight fit'.

 

---

 

But point B)... there is no narrowing of the adaptor, no shaping 'dip' inwards, just the whole section of it that slides into the enamel pipe top, is similarly "loose" a fit. By a few mm's.

 

It's this join that concerns me, as it seems the seal between the two seems to be made simply by the weight of the adaptor/ twinwall/ hat (this whole formed section all banded together well) just resting on ( albeit within) the enamel pipe. If any tiny rocking here... smoke will surely escape into the room. If I put 3mm rope around, it will disintegrate after a while, & I have no way of telling if it has done so. Because I cannot see it.

 

Zoot

[dpmiller]

needs a delicate touch with enamelled pipe, but is cutting the F and/or M bits off it an option, if one is too big and the other too small?

[PeterW]

@zoothorn this all sounds standard. What cement / sealant did you get ..???

[zoothorn]

2 hours ago, PeterW said:

@zoothorn this all sounds standard. What cement / sealant did you get ..???

I have some standard stuff, a tub of Koss fire cement.

 

Does the male end of the enamel pipe, need to " rest " on the lip of the stove hole collar section? One thing I notice, is this male end is 1" longer than my stove hole collar which as expected is welded on, & the whole pipe sits unevenly upon the thick ring of the weld. So, my pipe doesn't rest on it's lip.

 

It's a facet of the stove being very 'handmade' that both the hole seems a tad too wide, and, the welded on collar section isn't high enough for the pipe to sit neatly resting on its highest edge.

 

But I bet what I am trying to say here isn't comprehensible. ButI can't explain it any better.

 

Zoot.

 

 

[zoothorn]

3 hours ago, dpmiller said:

needs a delicate touch with enamelled pipe, but is cutting the F and/or M bits off it an option, if one is too big and the other too small?

Hi dpm. Ive tested it upside down, to see if the female larger end will fit into my stove collar... but no, its a bit to wide.

 

Now your idea of cutting though, tallies with what I can think is the only way my enamel pipe ( male end) can sit inside the stove collar & its weight resting evenly upon the top lip of the stove collar.
 

But I don't know if this is the way these two sections are meant to join.  I only know that obviously one slots inside the other. 

 

If you enlarge my sketch, the length of the male end, & the length of the stove collar... are good for explaining what I mean/ one is a little longer than the other. Ideally I need them the other way round: the collar longer than the pipe... so... it sits evenly, resting upon the top of the collar. Surely this is the optimal way these two should join. But I don't know tbh.

 

Cut an inch off the enamel male end? Does anyone know what I'm actually trying to explain? I bet not.

 

Thanks, zoot.
 

 

[PeterW]

@zoothorn from what you’re saying the male end needs to be shortened slightly to fit better into the top however  I wouldn’t go too far ..! See the pic attached - red line should be depth of the stove collar on the top of the stove plus 5mm so you can get a decent seal of fire cement. 
 

 

Question .. can you reach inside the stove up into the flue or is there a baffle plate ..??

 

Next, I would fit the adapter into the top of the stove pipe on the floor, good liberal amount of fire cement around the flange and then reach inside the adapter (wear gloves..!!) and smooth / pack it upward into the gap with a small sponge. (blue arrows) Then let it set and it will be a pretty strong bond once fired. 

[zoothorn]

On 03/05/2022 at 07:44, PeterW said:

@zoothorn from what you’re saying the male end needs to be shortened slightly to fit better into the top however  I wouldn’t go too far ..! See the pic attached - red line should be depth of the stove collar on the top of the stove plus 5mm so you can get a decent seal of fire cement. 
 

 

Question .. can you reach inside the stove up into the flue or is there a baffle plate ..??

 

Next, I would fit the adapter into the top of the stove pipe on the floor, good liberal amount of fire cement around the flange and then reach inside the adapter (wear gloves..!!) and smooth / pack it upward into the gap with a small sponge. (blue arrows) Then let it set and it will be a pretty strong bond once fired. 

Hi Peter, got distracted with tarting up me workshop! back onto these final prep bits/ this job. Thanks for your input.

 

I'm not quite on board tho with 'fit adaptor into stove'. The only adaptor is 1m above the stove, adapting the black enamel single > into the twinwall silver 1m.

 

What I'm wondering ( I think my describing hasn't been sufficient maybe ) is the seating on the 1m single wall, into the stove. This pipe obviously has an inward 'male' end, obviously designed to go into my stove collar. But where should this pipe length actually sit upon? Where should it's weight bear down upon? this is my point.

 

It has two choices.

 

1). As it is IE just offered up, it sits ( awkwardly) upon a thick welded band around btm of the stove collar. This weld bonds the collar, to the stove. Its a thick, slightly uneven, very handmade weld band. With the pipe sitting upon this, the start of the shaped 'male end dip' of the pipe, is 1" above the stove collar top. Now, I could get all the 4 bits together, have the lot bearing down upon this weld band, get the lot super rigid ( somehow) without any possible movement.... then.... fill up this collar 4mm gap with cement. Somehow.

 

2) cut 1" off the shaped male end of the pipe. If I do this/ the idea behind this, is that now the weight of the whole 4 bits bear down upon the top of the stove collar. Dry it would of course make a fairly decent join. So somehow then I have to get the 4 bits joined, then, seat the lot into the collar. Then lift it all up, apply cement, seat the lot down. 
 

I do not know 2 things still though, X) which of the above methods is best, & Y) & this is still to be understood/ determined, how on earth to join the adaptor to the top of the 1m single length, if I cannot see what's going on ( as Ive tried to explain above).

 

If I had gone twinwall all the way up from stove, I could've factored out the problem Y). I might have also had a better fit into the stove collar too. But it was saving £40 using a single length (& having a huge 6" wide silver flue in the smallish cabin.. would be odd, bulky & incongruous).

 

Thanks, Zoot.

[zoothorn]

Ok I need to simplify. Step by step Q's. This job looks simple in principle.... but it is not, with the 4 sections I have.

 

Q no.1.

 

If I simply offer the single enamel length, into the stove collar, it hits a band of weld ( stove makers' collar join to stove top). It rocks L to R I'd say a full 8" at the top. So if I let go, the weight of it is resting on this weld join. 

 

Is this correct?

 

zh.

 

 

[zoothorn]

Ok, so my upper mark is where the 'male end dip' starts. There's a good 1/2" gap, to the other mark.

 

So the pipe must sit on something inside the stove (orthe two marks would be right next to each other).

 

The thing that prevents the pipe slipping down further, is a thick ring of weld, on the stove, within the stove collar.

 

Pics two & three show how much lateral " give " the pipe has if I rock it max one way, then the other.
 

It doesn't sit nicely flat n flush if I centre it, because the weld band it sits on, is fairly 'rustic' uneven.

 

Zh

[zoothorn]

So the load is bearing down on the weld, on the stove top.

 

I don't know if this is correct, or, if the load should bear down on the rim of the stove collar TOP instead (the only way this could be achieved, is by cutting off 1/2"+ from the bottom of the pipe.
 

THEN the two marks would be together, a good seal even as it is would be made ( so with adding cement.. surely an even better seal made).. and the load would be bearing down upon the collar rim.

 

The load itself is irrelevant/ there is nothing particularly heavy involved, but where it resides upon, determines (* I would think ) possibly whether a good seal, or a bad seal is formed at this important juncture.

 

* I am only speculating, to be sure, because it is critical a good & correctly made join, is formed: so I may be incorrect & the pics show what is expected/ what is correct/ to proceed as it is. I just do not know.

 

Thsnks, Zoot.

[saveasteading]

Returning to something I said earlier. This stuff is in diameters from 3mm to 10mm and would fill the gap and stiffen it, and give you something against which the fire cement can bear.

 

 

 

[Onoff]

Have you bought and installed that carbon monoxide alarm yet?

 

https://www.screwfix.com/c/safety-workwear/carbon-monoxide-detectors/cat10650015

[PeterW]

3 hours ago, zoothorn said:

So the pipe must sit on something inside the stove (orthe two marks would be right next to each other).

 

The thing that prevents the pipe slipping down further, is a thick ring of weld, on the stove, within the stove collar.

Using a decent angle grinder disc, cut 20mm off the male end of the enamelled pipe. This then will sit nicely inside the ring plus a nice smear of fire cement will seal it all. 
 

 

[PeterW]

3 hours ago, zoothorn said:

Is this correct?

Yes - see above. 
 

When you have this lot all done up there will be no rocking as there is mm movement in those rubber seals when they are fitted. 

[zoothorn]

16 hours ago, PeterW said:

Yes - see above. 
 

When you have this lot all done up there will be no rocking as there is mm movement in those rubber seals when they are fitted. 

Hi Peter, what are these rubber seals you refer to here?

 

I'm still not clear on my question no.1 above too. I asked if the pipe should sit upon the weld ring, & you replied "yes correct".

 

But just before you suggested cutting 20mm off the pipe.

 

---

 

Trouble is Im not sure if what I'm trying to describe, is comprehensible/ understood (often the way with text replies on forums: simply the point lost in translation).

 

My photo with tape marks -should- show what I mean. But in case not understood (I cant think of another way to explain how the pipe sits on a weld band, in the stove, creating this gap in my marks) a sketch:

 

 

 

 

 

 

[zoothorn]

Or maybe this helps clarify my Q no.1.

((Which is correct?))

 

Thanks, zoot.

 

 

 

[ProDave]

It matters not one jot what the pipe sits on, you just need to seal it with fire cement.

 

Cutting a bit off the bottom will mean it sits on the top of the fitting so will sit more level while the fire cement sets.  I would hold the pipe up slightly so you can fill all around with fire cement filling the gap then let it drop down so the tapered bit sits on the top of the stove fitting then leave it for the fire cement to set.

 

But before you set it, you want to sit the pipe there, check it's upright, project up and mark and cut the hole in the roof for the twin wall section. 

[zoothorn]

1 hour ago, ProDave said:

It matters not one jot what the pipe sits on, you just need to seal it with fire cement.

 

Cutting a bit off the bottom will mean it sits on the top of the fitting so will sit more level while the fire cement sets.  I would hold the pipe up slightly so you can fill all around with fire cement filling the gap then let it drop down so the tapered bit sits on the top of the stove fitting then leave it for the fire cement to set.

 

But before you set it, you want to sit the pipe there, check it's upright, project up and mark and cut the hole in the roof for the twin wall section. 

Ok thanks ProDave. I think you & Peter are aggreeing I need to anglegrind 20mm off. In a way Id prefer not to, & have the weight resting on the more solid weld band... but... sealing the difference between (which seems the critical

thing surely) -seems to me- compromised this way.

If it was china junk you see Id not be happy the lot sitting on the rim ( as after a while the heat might form a split in the stove collar-?), though the seal better this way. But as it seems well made I guess its ok plonking all 4 bits' weight onto the rim then.

 

Ok. But sealing the other end 1m above is my Q no.2.

 

Here is the gap (pic 1) no metal bracket can clamp these two, & any gubbins put on the silver adaptor before inserting, cannot be checked or seen (so how can I ever be sure this seal is good?).
 

There is -thankfully- 1mm of extra metal (pic 2) around @ the join, meaning my gap narrows to 3mm (1.5mm all around). So I'm happier about this gap compared to the lower end into stove. 
 

Pic 3 shows it simply sitting on the flue. It rocks dry like so, it is far from tight. Any tiny rocking here (at this junction) which if 600mm of the flue is above the roof outside is surely inevitable in wind.. means any seal gubbins Ive put on the silver adaptor, being unseen once the black pipe covers it, cannot ever be verified as still being good.

 

Is my concern about this upper junction understood? Is my point clear?

 

 

 

 

 

 

Ok I've a plan for this 

 

 

Edited May 6, 2022 by zoothorn
I do not have a plan for this/ I cannot remove this sentence. Please ignore this.

[zoothorn]

19 hours ago, Onoff said:

Have you bought and installed that carbon monoxide alarm yet?

 

https://www.screwfix.com/c/safety-workwear/carbon-monoxide-detectors/cat10650015

Hi Onoff no Im far from attempting this flue job yet.. as I still cannot understand the correct joining of these 4 pieces.

 

Thanks for link though/ will get in due course.

 

Zoot.

[zoothorn]

On 22/04/2022 at 16:01, PeterW said:

Yep - cut to the rough size then Chuck it into a sink full of hot water and it will soften. Then slide down the chimney section, hold down temporary with a few bricks on the ally flange and when it cools and dries properly just stick it on with some decent adhesive and some short screws and penny washers. 

Peter forgive me a newbie's question.. are these screws suitable, to fix the outer alu flange of the johnny down thru felt/ into my osb roof? 

 

Or do I need something 'special' ?

 

https://www.screwfix.com/p/easydrive-flange-head-flange-self-tapping-screws-8ga-x-100-pack/6553h

Thanks, zoot.

 

[PeterW]

@zoothorn the screws are fine, carry on 

 

The connector/adapter  one is easy. Stand the ename pipe on the floor and put a good lather of fire cement onto the top edge of the pipe and the adapter. Push them together and then wearing gloves, reach down inside the adapter and you can feel the bottom edge of the adapter. Using a damp sponge, push any excess cement up into your join and smooth it out the wipe any excess off the outside and wedge the whole pipe somewhere upright for the cement to dry. 
 

When that is dried, fit the enamel pipe into the stove, clip the extended twin wall into the top of the adapter and you’re all done.