My OKM model did not have a windowed oven door, so naturally I wanted one. 🙂 Initially, it seemed to me that wish would require getting a whole other stove. Later on, once I got more familiar with the fact there were many variations of OKM gas stoves, it seemed plausible I could simply swap doors.
My hunt began for an OKM in pretty bad shape (and low cost) that had a windowed oven door and was within a reasonable driving distance. Likely, it would take a while to find an item that would meet that tough combo of criteria. But I already had enough to do and learn, so my patience was in abundance. Patience finally paid off! Craigslist had one for $40! The poor stove had been stored for decades in a seaside home garage. The salty mist took a serious bite out of the stove’s structure. It looked trashed.
But the stove not only had a windowed over door, it also had a griddle, another feature that I thought I might like to add to my stove. I was totally lucky that the model was a very close match to my stove, so all the parts were interchangeable; doors, control panel, grates, oven racks, cooktop, etc. Hopefully, there would still be some salvageable parts. Experience had taught me, as bad as these stoves can look on the outside, because their ‘shell’ is so thick, there can be many salvageable parts hiding behind dirt, oil and rust.
One challenge I hadn’t explored in my restoration adventure was how to remove an oven or broiler door. Frankly, I had been avoiding until it was necessary. After a cursory examination, it didn’t look easy. I had attempted to remove a few doors on previous parts stoves. Removing the outside halves – easy. Inside halves – not so much.
Puzzle time! This type of task had proven to be my most AND least favorite part of restoration. It was one of those tasks, that due to my ignorance, would require time, careful observation, testing, exploring and deduction to understand how the parts were connected so I could disconnect them. Parts stoves are great for learning on. I can practice disassembling on a stove I wasn’t worried about reassembling.
So my first big puzzle to solve – how to remove the inside door half.
Removing the outside half was fast – no frozen screws (learning to be thankful for small mercies). The door insulation was a mess! Too many greasy drippings, I guess. I planned to replace the filthy fiberglass with nice clean insulation.
Looking more like a deep sea diving port hole, the window was attached to the inside door. There was an inner chrome frame sandwiched by two 1/4″ plates of glass. And all that was encased in an outer metal case. The entire case was attached to the inner door.
After studying my parts stoves, it was clear the inner doors were attached by two different mechanisms. At the base of a door, in the far left and right corners are arched door arms that connect to the springs and the ‘hinges’ (I don’t know what else to call them). The two hinges per door have pins that need to be removed and the springs have to be unhooked from the inner door extensions before that can be extracted. I did a little dance in the backyard once I solved this puzzle.
Oven Window Casement
Once the inner door was free, I removed the window casement from the door. The oven window is a collection of various parts:
- inner and outer metal window frames
- two 1/4 thick 9″x12″ Borosilicate glass panes
- 1/4″ diameter oven fiberglass rope gaskets, about 6′ total
- inner chrome frame that separates the two glass panes
Before swapping doors, I needed to restore the old windowed door, the oven window casement and the glass panels. The door surfaces were dirty, greasy and rusty. The chrome window casement was badly rusted, especially in the window gasket channels. The fiberglass rope gaskets were shot and needed to be replaced. The glass sheets were badly scratched, probably from cleaning abrasives.
Oven Glass
One of the glass panels was so badly scratched it was difficult to see through it, so I had to hunt for a proper replacement. Each of the two panels was 1/4″ thick and had to accommodate high temperatures so ordinary glass wouldn’t work. I thought a place that sold fireplaces and high temp gaskets might sell the right glass. They did not. All the local fireplace shops sold already made systems. No custom jobs. But one shopkeeper did help, telling me useful information.
I needed was something called BOROFLOAT 33, borosilicate glass with a load capacity of 450 degree C (840 degree F); a 1/4″ thick 9″ x 12″ piece. Something even Amazon doesn’t have!
Due to living in San Jose, there actually was a full service glass & window biz near me. It was the only one out of more than 5 or so glass businesses that knew what borosilicate glass was and had it in stock in stock! $45 and 15 minutes later I had one nice custom order piece of special glass.
Fiberglass Rope gasket
The gasket (gasket 1) that was closest to the outside was lightly brown and not in bad shape. The second gasket – closest to the inside (gasket 2) was rock hard, stiff and black. It actually took heat from a torch to get the gasket to release from it’s channel.
After removing both gaskets I derusted the frames and channels with a LOT of grinding and scraping, phosphoric acid, a little torch heat to speed up the chemical reaction. I replaced the old gaskets with new 1/4″ fiberglass gasket rope from a fireplace shop.
The gasket kit came with 7 feet of gasket material and gasket glue.
Results of using the gasket adhesive – good and bad news. Bad news is it’s not good to use too much glue, which I did. It dries hard. More glue means less room for the gasket to compress to fit in its channel. If it can’t compress enough, the entire set of glass and frames don’t fit right so the window can’t be installed.
Good news? Now I know. Also, With a little more thinking, since the rope gasket is held in place by the glass panes it seems the glue isn’t really necessary, except in the channel corners . I also decided to paint both frames with black high-temp Rustoleum spray paint to help suppress further rust formation.
Final steps
- unhook oven door from springs
- place plastic covering on floor to catch loose fiberglass fibers
- open lower door, so upper outer drop can drop away from upper inner door.
- open oven door and remove door screws to remove stove’s outer door half
- carefully remove old fiberglass insulation; wear gloves and long sleeves
- remove door hinge pins to remove inner door half
- place windowed oven door inner half in place
- insert hinge pins
- hook inner oven door to springs
- insert rock wool insulation around window frame
- place outer door half and screw in place
One thing I hadn’t considered; the door’s weight. With that windowed insert and thick glass, the oven door was nearly twice the weight. Since the doors were spring-assisted to stay open and to stay tightly closed, the extra weight put quite a strain on those springs. Future plans will be to swap the original springs for something a little heartier.