what lubricant to use on planer depth adjustment chain

I use Pedro's dry lube from the bike shop on all chains. I have been mountain biking for 30 years. You don't want anything on your chain that attracts/holds dust, and you don't want to run it dry. Any half decent bike shop will carry Pedro's products but can find at some other sporting goods stores.

Not the T9. It leaves a thick film and will gum it up. It is best for surface rust protection and not really intended as a lubricant. Not sure that anything is necessary and leaving it dry will prevent it from collecting chips and dust but if you feel like some rust prevention is needed due to humidity or other conditions, then I would use a dry lube.

Another vote for silicone, just keep it off any project wood because you will not get any finish to stick or remain on areas with silicone on it. Spray this or any similar product and let it dry before use. I treat rifles, bike chains, snow blower intakes and shoots . Spray it on a rag and wipe your cars weather stripping in the fall and you will avoid frozen closed hatches and doors. This is a good product with plenty of AI but I'm sure you can find others as well.

https://www.castlepackspower.com/index.cfm?Page=Castle%20Big%205