What is the screw size to put my brio train table back together

'Triangle Screws' are security screws so that you can't remove them. Your question is a bit to specialised for Fixya, so contact the maker direct. They may just say, "send it back and we will replace it, or repair it".

33592 Mighty Red Action Locomotive ' BRIO World Toy Trains

www.brio.us > railway > trains-wagon-and-vehicles > m...

Classic BRIO design: This durable, retro designed toy allows your child's imagination to flow and helps improve their fine motor skills and spatial awareness.

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is it because you're not sure how it should look when put together? Is it basically like a brio set ? If so whenever I put my sons together I start by making a figure of 8 shape if I have a criss cross piece otherwise start with a circle and build it up from there.

Perhaps this picture will help you to place the cogs in the right way...

I wish I could help - I have exactly the same problem! Train opened Christmas Day, worked ok. Batteries seemed to gradually die 2-3 days later. Replaced all 3 sets of batteries twice, but nothing. Initially I got sounds, but nothing now.

Look for and remove little cross headed (not triangular) screw.

Hi Tarja, your question is 4 years old, but here is the answer:
You've probably seen the odd shaped tiny screws on the underside of the train. Ignore them - they require specialized tools and only lead to the wheels and gears.
You just need to insert a small cross-tip screwdriver into the exhaust funnel of the engine and remove the screw completely. The black front of the engine comes off and reveals AAA micro batteries which you gently shake out of the engine and replace.
As ever so often - once you know how to do it, it is very easy.
And - no, I didn't find out myself either *grin*

The battery is easy to replace. The screw is located in the black "smokestack" and will require a small size phillips-head screwdriver to unscrew. The rest is easy--lift up on the black smokestack (I usually leave the screw in place), and the two AA batteries are located end-to-end in the body.

If you look in the funnel there is a screw. Undo this and the front comes off and the batteries will pop out. Put in the new batteries and replace the funnel and screw.

Alas, the traction drive on these Brio locomotives seems to have a pretty short life. According to a Brio rep, the only hope is to indeed give it a good firm solid whack down onto a hard surface (table or floor) in an attempt to get the internal pressure gears to settle down and get more traction. There's a 50/50 chance it might work. There is no other solution. Attempting to open it up will create a mess because it's almost impossible to get all the tiny loaded springs back into place. At least the lights and sounds still work, and it can be easily pushed around the track--it just will no longer do so itself...

There is a small screw hole on top of the train, down inside what looks to be the smoke stack.  Then insert 2 AAAs!