This is asked frequently. Try a search on this sub for "how to clean"

Dishwasher, top shelf, low heat if you can adjust it, and pull before the dry cycle.

You’d be surprised what you can clean with some warm soapy water and a toothbrush.

Paintbrush

You can either lick it clean, or scroll down and click on the quick link on the right for How to Clean Lego. I'll even copy and paste the link for you:

https://www.reddit.com/r/lego/comments/2grjvt/cleaning\_lego\_a\_quick\_overview/

The r/lego wiki on the side actually has a post about cleaning Lego that you might find helpful.

Lather up a small amount of plant-based, fragrances-free dish soap, in slightly warm water. For pieces that have a lot of dust and finger oils stuck to the surface, gently scrub with a soft toothbrush. Rise several times in clean water until soap bubbles are gone.

Shake water off pieces (or use salad spinner) and place them studs-down on a microfiber cloth or paper towel to air dry overnight. It is helpful to position pieces so that spaces that trap water are facing up if possible to facilitate evaporation.

��I use a tiny bit of dishwasher soap, soak in a bathtub of Luke warm water for 4 hours. ��Stir every half hour. ��Drain tub and rinse with cold water. ��Place on towels with fans on it overnight.

https://www.google.com/amp/s/amp.reddit.com/r/lego/comments/2grjvt/cleaning_lego_a_quick_overview/

It depends on the situation. For assembled sets a combination of canned air and brushes work best for me. I use makeup brushes that come in a variety of sizes and shapes. The angled ones help with details. For stubborn issues I have used Qtips sometimes moistened with water.

I had a set the other day that was so gross from being left out for 25 years so I disassembled the whole thing and washed it (with soap and water) like it was dirty dishes, using strainers to keep the small parts safe from being lost. left it to dry for about 24 hours before assembling. Might have been a little bit of a gamble but holy shit every single piece looked brand new after. Looks great, didn't lose anything.

All the things mentioned by others here are valid, but the best thing about Lego is that at the end of the day you can take a lot of sets apart, rinse the parts off and reassemble the model when dry

https://preview.redd.it/8ntscq29jqda1.jpeg?width=3024&format=pjpg&auto=webp&v=enabled&s=f17298b41896e47ffab12d5fc88b8e9777e39b43

Done for the day. I have more lego but no more room :(

You'll still get dust with that kind of cabinet, ways, ways less than with open shelves though. The gap around the door is large enough to let dust pass so You'll have to dust from time to time.

Bro got the Republic Dropship with AT-OT, thats a grail right there. Such an awesome collection.

Disassemble and keep the sets separated, wash all plain parts in a clothesbag in the washing machine at low temperature with a bit of curdsoap, do not do that with sticker and print parts or minifigures. Rebuild and enjoy. Edit:don’t wipe them dry but rather let them dry by air. You might get smears, especially on tiles and such.

The best would be to disassemble and wash. If you don’t want to go that far you could get a couple interior detailing brushes and use some soapy water and give them a gentle scrub.

Take em apart. Wash them with soap and water in a giant bin. Get new stickers.

Ain’t no way around it, those are filthy lol

That republic drop ship and at-ot look beyond saving, I'll just take them off your hands for you. You know... Despose of them properly obviously.. 😏😆

I often just disassemble and reassemble. Cleans the set and you have the fun of building.

My method:

1. Break down al the pieces and put them into gallon ziploc bags about 3/4 full.
2. Two squirts of dish soap, then fill bag with warm water and seal.
3. Let sit overnight.
4. Drain water out of bags and spread pieces out on towels to air dry for at least 24 hours.
5. Move pieces around during drying process so none are stuck together.

At this level of dirtiness I would personally just completely take it apart and wash the bricks with warm soap water and a rag, then let them dry for a day or two (not on direct sun). Put the stickered pieces separately and wash them gently to preserve stickers.

If it was slightly less dirty (read: more dust and less sticky) you could simply shower it, but the hard dirt that seems to be stickied on the bricks won't go like that.

For gentle mainteance every few weeks a can of air (or electric air duster) and brushes will get the dust off.

There's a whole cleaning guide in the side bar

Warmish water and an electric toothbrush

I use a car detailing brush, but have a handheld vacuum there so I'm not just moving the dust around.

I use a makeup brush, then I blow off any remaining with compressed air, and I think the key is running an air filter in the room and full blast for the day you do it. Blowing the dust off just means it will resettle in a few hours, the air filters gets the majority of it before that happens.

If you do it once a week compressed air works. But it needs weekly maintenance

Water is going to leak in-between each and every piece, and then when left in the dark and without much ventilation... yeah you're going to wind up with mold after awhile. At the very least some stinky gunk.

I have a fine mesh laundry bag. I disassemble, then put in washing machine on delicate cycle. A small amount of mild soap. Works like a charm!

A little simple liquid soap, warm water and toothbrush. For that level of dust/grime, that will be the quickest method (cleaning with compressed air won't be enough and cue tips/paint brush will take forever). If you do wash the pieces, buy a salad spinner, works great for drying pieces quickly.

I run a bricklink store put it in a mesh laundry bag then put in washer with alittlw detergent. That's how I clean bulk and anything that dirty

Take apart. Soap and water. Dry. Rebuild

Throw it in the washer

Serious answer, take it apart, run the pieces through a salad spinner with a few drops of dawn, drain salad spinner and spin another 30 seconds to get rid of excess water, lay out on a towel overnight. I assume this is the Death Star, it’ll take 9-10 salad spinner loads and two towels to lay out. The next morning, you’ll have clean, dry legos, put it back together or sort pieces and store. I had the big 2012 R2D2 spill out of the box in my attic and the pieces sat there for 12 years. I finally got all the pieces together and used this method a month ago. Put it together good as new

Put a good portion of them in a pillowcase. Tie it closed. Put in washing machine on delicate with a small amount of detergent. Hand pillowcase on line to drive. Perfect.

Compressed air or a soft bristle paint brush work best for me!

I like using swiffer papers. They take up dust very well.

A mild soap and soft bristle tooth brush with warm water will get the stubborn stuff. No vigorous strokes if you trying to avoid scratches. Set on towel to dry.