# Origo/CookMate gimbals



## AdamLein (Nov 6, 2007)

I've noticed a few people on this forum use non-pressurized alcohol stoves by Origo or CookMate. I've just received one and I'm a little bit baffled by the gimbal brackets.

They look like this (picture is rotated to the right, sorry):










You use thumbscrew (a) to attach the big square plate to the end of the bracket near (d). The stove is attached to the big square plate, and the bracket is mounted on a bulkhead via the three holes in the top left of the diagram. The whole thing should be rotated left from how it's depicted in the diagram.

What baffles me is the following: the instructions say that you use the thumbscrews to adjust the friction. However the bracket is jointed on a sliding joint -- but it can only fold in one direction.

Does anybody know what this joint is for? The instructions seem to imply that the gimbaling axis is the line connecting the thumbscrews, so another joint doesn't seem to have any function. I've never used a gimbaling stove before, so I don't quite know what to expect.

Any thoughts?

Further info: I'm planning on mounting the stove in the well that the old (pressurized alcohol) stove used to sit it, the thumbscrew axis oriented fore-and-aft. My C27 is the "galley forward dinette" layout depicted here. I plan to arrange that joint so it can be used to keep the stove level on the starboard tack (if I use it at all).


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## sailingdog (Mar 19, 2006)

Yes, the thumbscrews go through the hole in the right end (of your image as posted) of the big square plate. That puts the axis of rotation about where the pan's contents are...so that the pan's contents slosh the least. The further the pans are from the center of rotation, the bigger splash it makes...

IIRC, the sliding part is to allow you to lock the stove and prevent it from swinging.

You can see the setup in this image of the assembled stove and bracket:










photo courtesy of binnacle.com


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## AdamLein (Nov 6, 2007)

Good point about the sloshing. But in that case, the stove's ability to swing can be made entirely dependent on the thumbscrews. When I want it to swing, I loosen them; when I want it to stop, I tighten them. When do I slide the slider?


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## sailingdog (Mar 19, 2006)

It's been years since I used one of these things...but IIRC, the sliding part is to prevent it from moving when not in use. 

This is yet another serious advantage of sailing a multihull. 



AdamLein said:


> Good point about the sloshing. But in that case, the stove's ability to swing can be made entirely dependent on the thumbscrews. When I want it to swing, I loosen them; when I want it to stop, I tighten them. When do I slide the slider?


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## AdamLein (Nov 6, 2007)

Okay, I've figured it out. It is as described by both the instructions and SD, though I will endeavor to provide a bit more detail for those interested in installing their own.

Note this is applicable to either CookMate or Origo single- or double-burner portable alcohol stoves, as they use the same sort of gimbal brackets.

Each bracket is formed by three plates; there are two brackets for the stove. Part (d) in the above image involves two of the plates. The one on the left in the image is the bottom plate and mounts to your bulkhead (I'll call it the mounting plate). The one on the right in the image is the upper rotating arm of the plate (I'll call it the arm). The third plate is the other big thingy in the image (I'll call it the stove plate) and attaches to the stove. The arm attaches to the stove plate via the thumbscrews, and it is indeed around the axis through the thumbscrews that the stove swings.

The arm is permanently attached to the mounting plate via a sliding hinge. When the stove is not in use, or when it is in use but you don't want it to swing, the arm should be in the "bent" position. If you mount the mounting plate with its bottom edge flush against the bottom of the well in which your stove will sit, then with the stove resting on the bottom of the well, the arm will be bent 90 degrees. Then when you want the stove to swing, you lift it up through an arc until the arm is parallel to the mounting plate, and lower it into place so that the arm "locks". I chose to mount the mounting plate higher up in the well; there's a certain maximum height after which the stove will never rest on the bottom of the well, which I considered undesirable.

All in all, now that the installation is complete, I'm quite happy with the results. The stove is securely mounted, swings through a large arc without meeting obstruction, and can be opened while in the "at rest" position so the "wicks" can be removed and filled.

I've also used the stove a few times -- not while underway yet -- and it brings a can of sauce to a boil in under three minutes. The other concern I've read about the nonpressurized alcohol stoves is in regards to the recommendation that water can be used to extinguish alcohol flames -- it's often mentioned that the use of water is just as likely to spread invisibly burning alcohol around and into the bilge. This would be valid if we were dealing with a basin of alcohol, but in the case of the stove, the alcohol is soaked into an absorbent textile material packed into a wide, flat can. If I needed to, I could douse the stove with water and no alcohol would get anywhere. I've even turned the can completely upside-down without alcohol spilling out, though it was not totally full.

As such I'd recommend the stove to others... easy to use and easy to install once you wrap your head around the gimbal brackets.

Here's the stove in the "down" or non-gimbaling position. The swinging arm is at a smaller-than-90 degree angle because I mounted the mounting plate higher:

From Stove installation

And one of it in the "up" position that allows it to swing. Sorry for the mess:

From Stove installation

For those of you with the galley-forward model Catalina 27: I mounted the brackets in the vertical line with the mounting point for the swinging cradle that carried the old Kenyon pressurized alcohol stove, good riddance. This enabled the cover to open fully, left some storage space outboard, and doesn't create any interference when the stove swings. I mounted it with bolts through the bulkheads fore and aft of the stove.


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## patrickrea (Aug 20, 2007)

Looks good. I bought a Cookmate 4200 (the drop in style) at the Toronto show to replace my antique 206 pressurized beast. I cant wait to drop it in and make some coffee.


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## Ritchard (Aug 15, 2011)

This is an ancient thread, but I hope to resurrect it. I got a set of these gimbals in the mail this week - along with all the other accessories you can get for this stove, and went to install them yesterday. The instructions for the gimbals are somewhat lacking. 

If I understand Adam's description above, the odd slider hinge is to allow the stove to swing backward(forward?) to sit flat on a surface below the stove, is that it? And to accomplish this, the bottom (static) part of the mount plate should be installed at the level of the surface below.

In my boat, there is a rather large well, which I am sure once held a propane stove with oven. There is now a microwave in the bottom part of that space, as I don't see us making many birthday cakes on the boat. I guess I will need to install a shelf above the microwave for the stove to rest on when in gimbaled mode.

For plannings sake, I guess the stove will swing back about 4 or 5 inches, and drop about the same amount when put into static mode?

Have I pretty well got it?


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## bobmcgov (Jul 19, 2007)

Sounds correct. FWIW, Origos (Cookmate is a clone) came with or had as an option a SS liner pan set up to take these gimbals. It is roughly 20.5x16x6" and offers both a crumb catcher and a resting surface for the stove in 'down' mode. Our boat came with one & we are incorporating it into the galley design. It seems you need to choose whether you want your stove to drop forward or back & mount the side plates accordingly.

You should be fine with Formica-covered plywood under the stove. I like the idea of a fire-resistant catchbasin there anyhow, just in case a dollop of burning oil escapes containment. Hate to have that end up in the bilges!


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## AdamLein (Nov 6, 2007)

Ritchard said:


> the odd slider hinge is to allow the stove to swing backward(forward?) to sit flat on a surface below the stove, is that it?


That's my best guess. In the first photo in my last post, the stove is showed in the low/nonmoving position. To get it there I lift the stove by the until the slider "disengages" and then push back. During installation, I made sure to mount the swing brackets low enough that I would be able to do this. I think I had the option of mounting the swinging brackets so that it would swing either forward or back, and chose swinging-back because there's a lot of space outboard of the stove, and this bar inboard of it.

That said, nowadays I almost never ever drop the stove into the nongimbaling position. I used to do it only to open the stove and get the burners out, but I've since gotten the hang of doing that with the stove in the gimbaling position.

[/quote]And to accomplish this, the bottom (static) part of the mount plate should be installed at the level of the surface below.[/quote]

Erm... not sure about that. If you're setting things up the way I did then you want the stove to sit on the surface below when in the "swung down"/"low"/"nongimbaling" position, so that sets a limit on the highest acceptable position. The other limiting factor for me is that too high, and it would have been limited in its gimbaling range (and probably its swing as well) by the structures inboard and outboard of it.



> I guess I will need to install a shelf above the microwave for the stove to rest on when in gimbaled mode.


Hm. I say "gimbaled mode" to mean "stove is allowed to swing freely with the rolling motion of the boat". So in that case, the stove bottom must not be resting on anything for gimbaling to work.

For non-gimbaling mode, any reason to simply let the stove rest on top of the microwave?



> For plannings sake, I guess the stove will swing back about 4 or 5 inches, and drop about the same amount when put into static mode?


Can't recall, though I'm hopefully going sailing today and could probably check for you. In the meantime, a bit of trigonometry can give you the answer (the line from the outboard-most corner to the thumbscrew is at a certain angle from the vertical. Add the maximum angle of heel at which you expect to cook, sine of the angle times distance from corner to thumbscrew gives you the maximum lateral distance of the corner to the vertical line through the thumbscrew).


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## Ritchard (Aug 15, 2011)

AdamLein said:


> Hm. I say "gimbaled mode" to mean "stove is allowed to swing freely with the rolling motion of the boat". So in that case, the stove bottom must not be resting on anything for gimbaling to work.


I wrote that a bit too quickly this morning.



AdamLein said:


> For non-gimbaling mode, any reason to simply let the stove rest on top of the microwave?


I think I'd like some kind of shelf below so that it will catch spills and such.

Thank you all for the input, I am gonna get it sorted. I may build a quick mockup so I really understand the proper install heights. Though it shouldn't be that hard, instructions could be better.


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## bobmcgov (Jul 19, 2007)

Ritchard, could you do us a humongous favor & measure the overall height of your assembled gimbals in "up&swinging" mode? We also are building mockups & it would be lovely to have that dimension.  Most third-party descriptions place the gimbals at 9"h, but the makers are mum. Thanks in advance! I'll try to post a pic of the Origo liner tray today.

Edit: Here's a photo of the Origo CookPal stove pan, to which gimbals were once riveted:



Outside dimensions are 15.5"d X 22"w X 7.5"h (3.5" front height).


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## Ritchard (Aug 15, 2011)

Bob,

I wish I had seen this earlier, I was at the boat all afternoon and could have measured. I may be back again Thursday. I sure like that pan, great bit of kit.


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## bobmcgov (Jul 19, 2007)

No rush. We're _years_ from launch. I meant to buy just the gimbal kit at the Defender sale, but forgot. The stove itself will have to wait for a place in the budget queue.

A sheet metal shop could fab one of these pans up in stainless or galvanized real cheap. Galvanized wouldn't last long in a hot place but might in cold, fresh water.


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## Ritchard (Aug 15, 2011)

Bob, I am on the boat, cursing at the pouring rain. Those specs you needed were 9" in closed position, 9-3/4 in "open" position, and 1-1/2 " wide.


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