Repair tips & tricks

Here you can find some common repair tips and tricks for (Roland) synthesizers


Fix red glue problems on 80’s and 90’s Roland synthesizers

A lot of 80’s and 90’s Rolands suffer from a problem with the glue holding the weights in the keys. This glue somehow breaks down and starts running down the keys. Symptoms are stuck keys, metal plates that fall out of the bottom of the keys and a pink / red glue that drips from out the keys.

Models affected are (amongst others):

  • Roland JV-80
  • Roland JV-1000
  • Roland U-20
  • Roland D-70
  • Roland JD-800
  • Roland XP-80
  • ….

This problem can render the unit non-playable. Because this is such a common problem a lot of people have been trying to find a solution and found one 🙂 : Sodium Hydroxide.

You can use sodium hydroxide to remove the glue completely effortless. All you have to do is remove the keys which isn’t very difficult in most cases.

A few pictures of the problem:

The only place I found to sell sodium hydroxide (draincleaner) is Kruidvat in the Netherlands.

It’s this bottle:

20150621_155014 (Medium)

It’s only 1 or 2 euro’s and it’s plenty for one synthesizer.

Caution: sodium hydroxide mixed with water makes caustic soda (bijtende soda)!! Dangerous stuff! Make sure it doesn’t touch your skin or eyes!

Remove the keys and make a solution of 50 grams per liter water with this stuff. Use plastic containers and luke warm (lauw) water. Don’t use super hot water because it can warp the keys. Carefully put the keys in and let them soak for an hour or two:

You can leave it overnight but the caustic soda only works for so long. I’ve experienced refreshing the caustic soda every two hours works a lot faster. You need to refresh it 2 or 3 times. It takes longer for the weights to drop out of the black keys than the white keys. Sometimes the weights of the black keys need al little help with a pair of pointy pliers. They should come out very easily though. If you need to use force just soak that key longer.

After just 15 mins of soaking most of the red glue is already gone:


After all the weights have fallen out of the keys carefully get rid of the caustic soda and rinse the keys with water and soap. Let them dry and re-glue the weights.


Fix non working keys

Will update soon

Fix non working buttons

Will update soon

General U-20 tips & tricks

Just visit this site: U-20 website

How to enter test-mode on some synth’s

Will update soon