Lye is caustic. That should never ever be used in anything but a workshop, with safety measures on you, and running water and vinegar nearby. Chemical burns can result.

The cabinets should have been finished before being hung. The boxes should have been finished before being constructed even. You need a professional with a spray gun and professional grade products. It would be best to uninstall the units and spray them in a clean room.

And any tips on the lacquer or varnish to use?

From reading your dilemma, you are not ready to take on this project.

Suggest hiring a pro to complete the work.

I agree get a pro NOW before you do some real damage.

Money is the thing. The guy who made the kitchen for me is a carpenter but has never done a kitchen like this out of birch ply. The kitchen had to go in prior to move in date and so we just decided to get him to finish it now as were under pressure with money and moving out of rented before starting mortgage in new. From reading the site of the people who made the reference kitchen we used this sounded a lot more straight forward than it is! They told me they just rubbed the wood lye on with a rag (protective glasses and gloves obviously) and let it dry. From looking online then the option is to use water based Eco lacquer I believe? Others using oil varnish mention it yellows and I really want to avoid that. One option is to get him to do it for my over a weekend when we are not home. The unit is 4 x floating shelves and 4 x deep drawers plus a casing for the boiler. Other option is remove the drawers and shelves and he takes them to the workshop to do.

Really my question is about preventing the wood from yellowing and what to use on it. Wood lye is what was used on the reference kitchen. I'm concerned about the lacquer or varnish option yellowing the birch. So if anyone can advise on those points, the carpenter and my partner (who is a decorator) are going to do the application of the lye and varnish. Just don't want to destroy the wood or ruin the finished effect I am looking for.

Water based polyurethane is much less prone to yellowing. I am not familiar with the process you are using, so I don't know if it is compatible. Polyurethane can be deteriorated from underneath if the wood has non-compatible chemicals in it. For example, if wood stripper is not completely neutralized by mineral spirits, it can ruin the new poly on a refinished piece. If the process you are using leaves the wood neutral - not acidic or basic and is compatible, water based polyurethane is a finish that will have less yellowing.

You can pay a pro now or pay a hell of a lot more after you screw it up (and it can't be fixed), your choice.........................

I hear ya. As mentioned, my partner is a painter/decorator. But neither he, nor the carpenter have worked with this wood to achieve this raw finish that I want. I'll go back to the reference kitchen guys and ask them what finish to use over the lye :)

Lye WILL burn holes in your skin. It MUST be neutralized before anything can go over it as a protective finish. That may end up warping the wood.

This is so not a process for an amateur designer and amateur carpenter.

Please contact me. (800) 242-8160, M-F, 9-4pm EST. I can provide application instructions and offer suggestions on what to use as the finish.- Jennifer Sanderson

Great customer-focused approach...I'm based in Ireland do you have a local number? Or UK? Otherwise email is excellent as it is very costly to call.

My email is jennifers@wocausa.com

Email me and I can send you instructions and the # for WOCA UK

Email for WOCA UK, pha@woodcare.com

See link for WOCA Wood Lye instructions. Because this is not a flooring application, denib with a green pad (cut to fit) attached to an orbit sander. Finish with a WOCA penetrating oil or waterbased poly. WOCA Wood Lye Instructions

Thanks for the useful information!

I know its been almost three years, but I am really curious how the Woca product worked on your cabinetry. Please update if you have a chance. Thanks!