Plywood vs MDF

Hey,

My prof has recommended substituting plywood for MDF for the Darwin that my team is building. The reason being that plywood is much more durable.

I'm just wondering if anyone has considered (and rejected?) this before. What are the advantages of MDF?

We're ordering parts right now so a quick response would be greatly appreciated.
Thanks,

Jacob

MDF is flatter, more uniform and therefore less likely to bend.
For the build platform that is an advantage.

I tried plywood the first time around and found it to be miserable. The heat from the PLA causes the layers of the plywood to separate over time. This means that you get an uneven bottom surface which can mean that prints can slump over.

Also, I live in the south east US, with the humidity we have here, plywood likes to warp.

I switched to MDF and the problems went away

~ MDF looks better cuts with a clean edge and drills with sharp edges no splinters.

I have tried using both MDF wins every time.

Bertha is made from Plywood.

From

Darwins made from hard wood plastic bread boards MDF and Ply.



Mendel MDF.

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Bodge It [reprap.org]
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BIQ Sanguinololu SD LCD board	BIQ Stepcon	BIQ Opto Endstop
BIQ Heater Block PCB	BIQ Extruder Peek clamp replacement	BIQ Huxley Seedling
BIQ Sanguinololu mounting	BIQ standalone Sanguinololu or Ramps mounting	Print It Stick It Cut it

My rep strap: [repstrapbertha.blogspot.com]

Buy the bits from B&Q pipestrap [diyrepstrap.blogspot.com]
How to Build a Darwin without any Rep Rap Parts [repstrapdarwin.blogspot.com]
Web Site [www.takeaway3dtech.com]

It's good to see people doing well with MDF.


I have a fully working Darwin. However fed up with glueing acrylic back together after tightening a bolt too much. I am rebuilding the whole thing with 16MM MDF and stealing the important / reliable parts.

So far reprap 2 (the revenge) is going smoothly.

Stephen

Another question:

I have access to an OMAX waterjet cutter but not a laser cutter. Acrylic cannot be waterjetted effectively, but polycarbonate can. Would polycarbonate make a suitable build platform? If so, what thickness would be appropriate?

Hi ,

can anyone guide me for the selection of home furniture.

Plywood is costly but durable and MDF is cheaper but not as good as ply.

Is it right to go for MDF for making wadrope,bed,loft etc .

Please suggest.

I wouldn't. I use only ply and "normal" wood for furniture. MDF absorbs water too readily to be of use in making furniture in my opinion. At least for durable furniture, that is...

I have been a professional cabinetmaker for over 30 years, and as such am amazed by the frequency of use of mdf as a printer component. Both plywood and mdf have good tensile strength. Certian of each have good compression strength. MDF has absolutely no strengh on its endgrain (both directions) at all. If you are going to use plywood, I would recommend finnish or baltic birch. These are among the sturdiest and least espensive of the hardwood plywoods and aer often available at wood working stores in small sheets. Avoid lumber core, and any softwood plywoods. The thing with wood, is that even if you cut it to machine tolorances, something that I do for joinery, the wood will have much greater diminsional instability than any of the other materials in your printer, which could then introduce misalignment.

I'm building a box/support structure for my Mendel, and it's going to be 3/4" baltic birch ply. Why so thick? Because I have a bunch around from building furniture, and it's good stuff. One 4' x 8' sheet will run you about $45 these days, and you can get it at Lowes or Home despot down to 2' x 2'. If you're buying the wood (not recycling on-hand stock like I am), 1/2" is probably the best choice. Heavier than 1/4" but the 1/4" quality is spotty unless you are spending more for nice stuff (which generally ain't in big box stores).

MDF will powder over time from vibration and absorb moisture; I'd stay away from it. If your plywood is separating at the temperatures that we're using, you're buying cheap plywood, may Mendel have mercy on your soul.

jbayless Wrote:
-------------------------------------------------------
> Hey,
>
> My prof has recommended substituting plywood for
> MDF for the Darwin that my team is building. The
> reason being that plywood is much more durable.
>
> I'm just wondering if anyone has considered (and
> rejected?) this before. What are the advantages of
> MDF?
>
> We're ordering parts right now so a quick response
> would be greatly appreciated.
> Thanks,
Hi,
I would recommend MDF for your printer.
As mentioned in posts above, it is flat, easy to work.
One important factor is moisture, but any wood is sensitive to moisture changes and hence I would strongly recommend that you seal it.
I have painted my mdf.
Especially the ends/cuts needs to be sealed.
I paint it all over as you may spill azetone/metho/oil etc on the machine.
I have had my MDF painted machine in my garage with sunny 40+ days and rainy 5 degrees day/nights and have not had any issues.
Regards
Jan
>
> Jacob