Rice filled trivet
 

Has anyone made one of the rice filled trivets and then washed it?

No, but I would think the rice would swell.

My thoughts exactly which is why I'm asking in case there is some trick someone has found. :-)

i have rice in my heating pad i put around my neck. can't be washed. if they had micro beads they might be washed. not sure of washing machine though. perhaps in a lingerie bag.

They make small bead pellets ( I have some) and they are micro safe and washable.

I made a couple of the heat pads for my husband and I but I also made separate covers so I could wash them the covers and not worry about getting the rice wet and making a mess. I just use snaps on the covers.

Of course you can wash it. Wash by hand, work quickly, use only warm or cold water and dry quickly inside a pillow case or something like that. I would put in the spin cycle of my washing machine which would get out most of the water, then put it into the dryer in its cover. Rice takes a long time and lots of heat before it swells. I would try it.

I just made 2 new ones for Christmas but I used lentils and I would only wash the cover.

After reading your question, I suddenly had this picture of you going to your washing machine after the wash cycle had finished and seeing your washing machine door propped open with all of the rice swelled up like an overflowing popcorn popper. Silly, I know. I do sometimes get funny, ridiculous images in my head; it keeps me entertained.