door gaskets in baby-mama-papa- bears

[mike zimmerman]

my question is should there be a gasket in the door of these stoves . i have come across them with gaskets but i believe that i read bob made these stoves with out gaskets . and if he did design it that way are most still air tight even now after time .

 

[webby3650]

I had to gasket mine. The doors fit very nice and tight, but there was still enough air getting in that the stove would get alittle out of control. Now with the gasket it runs much better. They weren't designed to use a gasket, but it helped mine.

 

[coaly]

You must realize that up to the point in time when the steel plate stove was invented, (Papa Bear 1973) all stoves were cast iron and required door gasket material. Some even between stove parts. It wore out, fell out, and could cause a stove to need to be shut down. In many homes, this was the only heat source at the time. So most knew to have replacement door gasket handy. (and find the cement dried in the can, duh) so the new stove having better control of the fire made of one piece welded construction was made even better not requiring gasket material replacement. It was a huge benefit of the Fisher. Most people thought a gasket was missing when they saw a Fisher, and many still do.

Most still seal well enough with the steel door seal (1 inch channel iron) as designed.
Doors loosen from lack of grease ! (Anti-Sieze takes higher temps than grease and lasts longer.)
If they squeek, they need grease !

If hinge pins or hinge pin holes get worn excessively (from lack of grease) the door can become loose fitting at the hinge side. Latch side is adjustable. New door pins (solid 3/8" rivets) normally cure the problem. Hinge plate holes elongated from wear can be bushed, or tightened many ways. (oversize pins) Depends on how critical you want to get. Not all stove faces or channel iron door seals were perfectly flat, or there could be a little weld spatter somewhere that holds them open a crack. The door drawings have a note pertaining to tolerance "IF" machining is done on cast iron door sealing surface. (door drawings also note; machining must be done before door hinges are fitted to stove) Machining was not normally done, so the sealing surface is as rough as the cast iron door surface. A perfect metal to metal seal involves finishing the sealing surfaces flat, usually with a milling machine. (like the machined surfaces on an engine block where parts are bolted on) Sanding to a flat polished surface at the 3 sealing contact areas is possible if rusty or abnormally rough. (notice when door is closed, the outer edge of the door doesn't touch the stove. The space between door and stove front plate is the thickness of door seal channel iron web) More on this later.
The two edges of channel iron (door seal) and the raised portion on door that goes between the channel iron rails are the three contact points. Removal of material must be minimal since the door hinge plates were welded into postion with door shut against these contact points. Since the hinges are not adjustable, removing too much material is going to make the air gap even larger. This is called lapping metal to metal as in steam valves and parts. A steam tight joint can be obtained without gasket, as long as it stays tight at hinge side. Those not aware of lapping metal to metal, or taking lots of time to make them mate perfectly, cheat with gasket material.
So if you must......... If the stove continues to burn more than you want it to with draft caps closed, the thin gasket material for door glass installation normally allows the door to close without undue force on the hinges. Round gasket material should be avoided. There is no gasket space or clearance between door and stove front for gasket material. The space between door edge and stove face is now going to be the thickness of original door seal channel AND added gasket material. This is what puts pressure and wear on hinge plates and door hinge ears. If you do cement gasket material in door seal channel, you need to remove all of it when replacing gasket some day. Build up of gasket cement will cause door closing problems and binding hinges. This removes easily with a wire wheel.

One plus I've found using gasket material is the door is much quieter slamming closed if it gets away from you.
Otherwise I wouldn't add it unless absolutely necessary.

 

[webby3650]

Thanks, for me it was necessary. My doors fit as tight as they can, I feel. The pins are so tight that I can barely remove the doors, the pins are very tight. Without the gasket, the stove went crazy with a full load. The spin drafts were closed and the pipe damper was shut. Now it is very controllable.

 

[coaly]

I've heard of doors warping, but never saw one. You could have done the dollar bill test closing the door on it and pulling it out....... Continue all the way around to determine where it's loose, tight, or a high spot preventing it from closing. Maybe even a straight edge on the sealing channel to make sure it's flat. Something wasn't right. All mine go down to glowing coals and die when closed.

I usually have to drive the pins out of doors to get them off when I get a stove. Then I clean the hole in door with a small round wire brush, Scotch Brite or wire wheel the pins, grease, and they fall right in. Door then lifts off easily. Door should swing freely too.

 

[mike zimmerman]

thanks coaly that is what i needed to know . this will settle a conversation i had with a good friend .. it does look unfinished but that is how its designed and it is maintenence free .

 

[coaly]

Here's the detail shown on drawings for the door casting at seal area. This gives you an idea of the engineering and cost of drawings, patterns, and casting tolerances.