curved cabinet doors

[madme]

Hi!
At first sorry for bad english.
I have a small workshop and want to growth that, So i decided to create some curved cabinet doors and i want to know is it possible for anyone to guide me how to create curved doors with mdf ??
i do that by Hand clamp but result is not good !

 

[Gregor]

Try this:


Or that:

 

[madme]

Try this:


Or that:

Tnx for quick reply and your guide, but the problem is i want to use cnc tools on doors so i can't use this videos because the cuts uses for curve mdf will cause problems with tools.I find some ways from create guitar but still not enough information.
Here is a photo of result that i want :

 

[madme]

UP !!  [big grin] [big grin]

 

[Svar]

Could you laminate it from thin layers? Can you even buy MDF thinner than 12 mm?

 

[madme]

Could you laminate it from thin layers? Can you even buy MDF thinner than 12 mm?

No i cant laminate it at all. and i cant use MDF thinner than 12 mm.
someone do this in our city and i want to know how he is doing this ? [eek]

 

[AstroKeith]

Could you laminate it from thin layers? Can you even buy MDF thinner than 12 mm?

No i cant laminate it at all. and i cant use MDF thinner than 12 mm.
someone do this in our city and i want to know how he is doing this ? [eek]

I'm pretty sure the panels are either made curved or later curved in a press. I believe the temperature for pressing mdf is 180C, which is an irreversible thermosetting action. I have heard of a re-forming process where the MDF board is treated with ammonia which allows the resin to move and when the ammonia dissipates the resin re-sets.

 

[madme]

Could you laminate it from thin layers? Can you even buy MDF thinner than 12 mm?

No i cant laminate it at all. and i cant use MDF thinner than 12 mm.
someone do this in our city and i want to know how he is doing this ? [eek]

I'm pretty sure the panels are either made curved or later curved in a press. I believe the temperature for pressing mdf is 180C, which is an irreversible thermosetting action. I have heard of a re-forming process where the MDF board is treated with ammonia which allows the resin to move and when the ammonia dissipates the resin re-sets.

I was thinking of doing this with press. but i dont know how to do this.
i tried to use vacuum press but was strong for this and broke the mdf.

 

[AstroKeith]

Could you laminate it from thin layers? Can you even buy MDF thinner than 12 mm?

No i cant laminate it at all. and i cant use MDF thinner than 12 mm.
someone do this in our city and i want to know how he is doing this ? [eek]

I'm pretty sure the panels are either made curved or later curved in a press. I believe the temperature for pressing mdf is 180C, which is an irreversible thermosetting action. I have heard of a re-forming process where the MDF board is treated with ammonia which allows the resin to move and when the ammonia dissipates the resin re-sets.

I was thinking of doing this with press. but i dont know how to do this.
i tried to use vacuum press but was strong for this and broke the mdf.

Once the resin in the MDF has set, you wont be able to bend it significantly. Heat wont help either as the setting is a one way process.

I really think that they are manufacturing the MDF board from base resin and fibres etc in a heated press.

What cant you build it up from 4 off 3mm thick sheets?

 

[Bob D.]

I  look at the image of the example you provided and it sure looks like it is laminated from two pieces. If not what is that line we see on the bottom of the panel.

Do you know that the panel face is routed after the panel is shaped or is it possible that the panels are created initially in this curved form with the design and not routed afterward.

Add a fourth axis to your CNC and place your pre-formed panel blank on there so it can be rotated under the bit.

 

[AstroKeith]

I think I agree with Bob, it looks like three layers of laminated MDF.

 

[Svar]

Agree with Bob and AstroKeith. Looks like 3 layers to me too.
I don't know where you are, but in US you can buy material similar to MDF called hardboard (high density fiberboard) about 3.5 mm thick. It's a bit more dense, but will bend into the radius shown.

 

[Oldwood]

I have done this with thin sheets of MDF and thin sheets of ply. (about3mm) The mdf was for raised panel paint grade and the ply was for a flat panel veneered. I don't have a picture of the painted doors but have attached a picture of the flat panel in the vacuum press and out. You need a glue with a rigid glue-line and enough open time to get it laid up.

We make the doors over height and width so they can be trimmed to size afterwards. We build a solid form to vacuum the panel to. We glue up the sheets then fasten them to the form in the middle top and bottom, then insert in form and pull as flat as possible before turning on the vacuum.

Spring back is a variable that is hard to predict and you need to do some trials to see what will happen. I find with tight bends it sometimes curls more after coming out of the form instead of flattening out.

It is a very time consuming process

I used a jig and a handheld router to do the raised panels. I think routing these doors with a CNC router would be a monumental task.

Good luck with it.

 

[Michael Kellough]

“someone do this in our city and i want to know how he is doing this”

Ask that guy.

Or do what Bob D said,

“Add a fourth axis to your CNC and place your pre-formed panel blank on there so it can be rotated under the bit.”

I don’t know how else to do it but even if I did I wouldn’t tell you. I don’t like the idea of asking other people to help you reverse engineer a process someone else has developed in order to take business from him.