Why do hollow core internal doors have striped/ridged edge?

[RLD]

Does anyone know why hollow core doors have a striped/ridged edge? And can it be removed? Hume brand hollow core doors from Bunnings were used in my home renovation. After painting, every door has a partial ridged/striped finish, on the edge, where the hinges are attached. I've been told this is how they're manufactured there is nothing you can do, or a power planer has "chattered" on the door edge leaving stripes, or the painter should have sanded to remove the stripes/ridges, or the carpenter should have filled to a smooth finish. QBCC said it was manufacturing and rejected it. I can't believe that, as Hume sell millions of these doors and nobody would use them if this was the finish. The old hollow core internal doors were smooth, for comparison. Would anyone know what this is, how to fix it, and who is responsible for the fix (carpenter or painter) please? Thank you. 

 

 

[RLD]

The contract does not include a list of products used, and there are none of your suggested references available. Thank you for trying. 

[JacobZ]

Hi @RLD,

I have only just read through your post and am sorry to hear this has happened to you.

It is entirely reasonable to expect this to be done as part of the painting process. It is not hard to do so I struggle to see why they have made this so difficult for you.

I'd be happy to advise you on how it can be done if you'd like to do it yourself.

Let me know what you think.

Jacob

[RLD]

Thank you Jacob. If you could explain the fix, that would be great. 

[JacobZ]

Hi @RLD,

Start by taking the door off the frame and removing the hinges.

Take your door to a location where you can safely stand it with the ridged face pointing up and you can move around it freely. You can lock it in place while you work with stacks of books or heavy boxes.

A random orbital sander will make light work of this job, but if you don't own one, you can always use a piece from a sandpaper roll wrapped around a sanding block to make sure everything stays nice and flat.

Start with 80-grit sandpaper to remove the ridges before bumping up to 120-grit to smooth the surface and 180-grit to finish it off. Brush the surface down to remove any sawdust.

Start by applying a coat of Dulux 1Step Prep Primer, Sealer & Undercoat with a UNi-PRO 100mm 9mm Nap Little Ripper Foam Mini Roller Set. Allow your primer to dry for 2 hours before applying 2 coats of your paint.

I imagine you'll have a schedule of finishes in your building plans and hopefully, some leftover paint that can be used to paint the door. If not, doors are typically painted with semi-gloss or satin enamel paint like this Dulux Aquanamel Semi Gloss White Enamel Paint.

Once painted and sufficiently dry, locate the screw holes in your door, reattach the hinges to the door and hang the door using the existing holes in the doorframe. 

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob