I am looking at the holes provided on the inner lip of the (classic) ash box door, and wondering how it is intended to be installed. It would seem like the holes being placed on the sides of the frame (like the larger fire box door) would allow the masonry screws/drill to reach in there. The opening is so narrow from top to bottom. Before I drill my own holes in the door frame, thought I would check and see if I was missing the obvious.
Hey Ruth. Originally motor bike spokes were used to attacht the cast iron parts into the masonry. Nowadays there are special tight fitting masonry frames available in which the door is being pushed tight (not sure if this is correct english…)
Hi @Ruth. This is a good question and @Theo.Dubois provides one good solution.
Indeed, as Theo writes, we recently developed sheet metal masonry frames for the Classic Line ash door and soot doors we sell. You can find out more about them here:
The cast iron frames are friction fit into the sheet metal frames and the joint between them is sealed on the inside with high temperature silicone.
Once assembled like this, you can mask the piece and install it as you build the masonry.
I believe you are already beyond this point so, yes, I would recommend that you drill one hole in each corner horizontally to be able to attach the doors with 1/4" (6 mm) shank, 1 3/4" (50 mm) length masonry screws. We place the frame and then trace the location of the holes on the masonry with a mechanical pencil lead. We use a hammer drill to make 3/16" holes. We then place the hardware and drive the screws by hand using a ratcheting 5/16" hex socket. We do this by hand in order not to strip the hole.
It is then important to seal between the ash door and the surrounding masonry. For more technical doors which experience higher heat, this space is sealed using the ceramic wool insulation strips that we provide. The ash door is typically at a cooler place in the heater and can basically be mortared in. The screws help to ensure the strength of it’s installation.
Thanks @max, you use the words I was looking for. Attached a picture of the use of the spokes.
Thank you @Theo.Dubois and @max for your responses. I truly appreciate the information, and since the face of my heater is already completed, I will plan on using the bolting method @max detailed. I was just reading the post about masonry hardware installation (I somehow did not see that before, even though it was right in front of my face, how embarrassing) but there are some extra details in this thread not listed there that are very helpful to me. Thank you so much.
speaking of ash boxes… Max, you were designing an ash box for your masonry heaters. Is it available yet?
Yes, we have ash drawers available:
In rereading this thread it doesn’t quite cover the screw holes for this ash door, as they go straight back, I’m assuming to the fire brick? Looks like they will just chip the brick since they are so close to the edge?
The beautiful ash box fits great into the space, but doesn’t fit through the door?
Advice?
Hi Claire,
Those internal mounting tabs came on the first round of hardware we had manufactured. If you cut those out with a grinder and drill holes in the side of the frame to mount to masonry on the sides, it should work. Let me know.
Regards,
Max
the forum is giving me the log in runaround?
How does one get a drill in the ash box opening to screw it in? It is inset back between the benches?
I’ve been having Forum log-in issues too.
Check above on this thread. Max detailed how to install the ash door. Just incase you cannot see that:
This is what I did. (Totally non-professional.) Pre-drill the holes where desired in the cast iron from the outside of the door frame. Place the frame in the masonry opening, level, use shims to hold it there temporarily while using a mechanical pencil to mark the holes in the masonry. Remove door frame and pre-drill the holes with masonry bit in the masonry, take care to drill to appropriate depth. There should be enough space for a cordless drill side to side. If not, you may have to angle the holes slightly, or use a short right angle drill. Place door, surrounded tightly by the ceramic wool into the masonry opening and line up the masonry screws through the door frame into the masonry. Use a socket and ratchet (not power drill) to put the masonry screws in. This will give you room to put the screws in. Put them in loosely at first until they are all in place, then tighten gently to not strip out the screws until level and secure.
That is pretty much exactly how we do it except we only insert the bottom piece of ceramic wool gasket first then the rest of the gasketing after the door has been screwed into place.
@dclaire, if you don’t have room to get a drill in you will have to rely on some combination of high temp silicone and mortar to secure the door into place. We have been working on masonry frames to make this process easier but don’t have anything in stock.
On my last two stove builds I’ve mounted the blower and fuel door after construction was complete using ceramic fiber paper gaskets and tapcon style masonry screws. I’m wondering about longevity of these anchors with expansion/contraction cycling. A friend has a stove built by the late Tom Trout and it used this style of mounting for the fuel door and some of the masonry screws have worked loose.
Do people have an opinion on this practice? I told my buddy he could certainly drill new holes somewhere else on the frame and put in new screws. My experience with these anchors is once the pop they are done.
Thanks
I think you are right Joseph, once tapcon style masonry screws get loose and the doors begin to wobble, it’s likely that the attachment needs to be modified. It’s worth trying to tighten them but if they spin, they have no grip. This is one reason that I recommend hand/finger-tightening them on the original install rather than using something like an impact driver to ensure that the masonry is not getting stripped out.
The method you describe here is standard, especially for the hardware (and accompanying screws and gasketing) that we are currently supplying. In my 20 years of experience, I had one door come loose that needed to be re-attached. While drilling new holes in the frame could have been one option, I tried the following technique which worked well…
I drilled and cut thread into the existing holes in the frame. I believe I used 5/16"/fine thread pitch and drilled the holes in the masony at exactly that same size. I used long-ish hex head bolts (3"?). The threaded connection is strong at the frame and the length of the bolts gives it a good anchor in the masonry, especially if you balance your tightening as you go around.
I consider this a retrofit technique since the original masonry screw technique potentially allows for more expansion and contraction and generally works well. I would definitely like to get more info about hardware attachment out there and thank you for bringing this up.
One more thought which applies to cleanout doors is that there are professional builders who use a high temperature silicone only to attach their cleanout doors at the end of construction. You apply the silicone to the inside corner of the frame, set it in the rough opening, and then clamp, shim and level. If any silicone squeezes out visibly, make sure to wait for it to set hard and then cut and remove it rather than trying to clean it up wet which makes a mess.
Ash doors can also be set this way although ideally in tandem with the screw mounting method since these doors are operated more often, have a latch, and are subject to more mechanical force.
These techniques were described to me by @borealheat. Thanks.
I have generally used sheet metal masonry frames for cleanouts and ash doors which has the advantage of a strong connection to the masonry but the big disadvantage of having to set the frames in the middle of wet construction which means masking and taking care of them during construction.