Mdf or plywood to use for cutting

[Courtney]

Im looking for cheap wood to cut with my sculpfun. At the moment im usinf mdf 6mm. I was wondering if plywood is easier to cut through than mdf?

Thanks

[jkwilborn (Jack Wilborn)]

MDF is wood ground up and glued together…

I find it more of a problem… plywood also has glue and it’s not very consistent between sheets and batches.

I use some 3mm Basswood from Amazon, cuts well and is relatively consistent. I have lost more than one job because of pockets of glue…

[patricr (Patrick Rose)]

I use a laser-safe MDF from JPPlus.com. Does not smoke or char much at all.
LaserBits 12" x 24" Econo Laserable MDF

Please note, the size is not exactly 12x24"- see the details tab to see this number.

[ferg (Marion Ferguson)]

I use maple, birch, or cherry veneered mdf all the time. Cut 3mm material on my CO2 60W with speed at 10mm/sec and power at MAX 25%, MIN 25%

If I want to cut 1/4"/6mm I bump the MAX power to 30%.

[jkwilborn (Jack Wilborn)]

Yikes, $7 a sheet, probably why I don’t use it…

[patricr (Patrick Rose)]

Yep- forgot that and picked it quickly out of a spreadsheet. Here are some much lower-cost options:
Amazon:
3MM MDF Sheets - 12" x 24" Sheets (12 Pieces) Perfect for Laser Engraving or Crafting by WOOD-EVER
3MM MDF Sheets - 12" x 12" Sheets (20 Pieces) Perfect for Laser Engraving or Crafting by WOOD-EVER
Trotec | MDF Wood Sheet | 10 Pcs | Finish Untreated | 23.50"x11.75"x1/8” | Laserable & Engravable MDF Wood Boards

WAI.com
LIGHT PREMIUM MDF ~ 1/8" SKU: W0-LMDF-1.8

I might add that how they are shipped is important. Poor shipping and the hassle of returns/refunds is a consideration if you establish a track record of damaged goods.

[Courtney]

Thanks for all the help. I was wondering if anyone can tell me if mdf or plywood is easier to cut?

Thank you

[LSS (Samuli Samuelsson)]

Hi.

@Courtney

I was wondering if anyone can tell me if mdf or plywood is easier to cut?

Unfortunately the reality of it is that no-one really can tell You -or to anyone else for that matter- that.
The main reason for that being the fact that there’s a gazillion ways to manufacture either MDF or plywood, and up until recently the materials ability to be cut -or marked- with visible wavelength laser haven’t even been on the list of properties to aim for.
So all the materials sold under those two looseish marketing terms have been engineered and manufactured with entirely different goals in mind.

While in theory MDF would be easier or at least somewhat more predictable to cut than plywood since the material is more homogenous by nature, the bonding resin that ties those medium density fibers together throws a huge wrench onto that theory in the real world.

So, we basically have three choices.
From the cheapest to the most expensive.

The cheapest is to cut what ever we can find cheaply or free, and don’t mind lots of trial and error, a bit of charring, occasional fires and occasionally ruined work.
Those tendencies can be greatly reduced if the cutting is performed in an inert (nitrogen if on a budget) atmosphere.

The next is to do extensive research on different moderately priced MDF and plywood varities to find the exact one that’s easiest to cut.
The problem is that one usually has to buy the whole ~2.5m2 sheet, not just small pieces to test on.
And when we eventually do find the least problematic material, keep our fingers crossed that the next sheet is actually manufactured with the same materials and in the same way.

The third is the easiest and also by far the most expensive, to buy either of those materials as “laser approved” stock.
Keeping in mind that not all the vendors are necessarily completely honest with their marketing claims and strategies .
Up to 10 times the price for putting a “laser approved” stamp on regular plywood may prove to be next to impossible to resist.

With plywood there is a fourth rather marginal choice for the HC DIYers, rollin’ Your own.
There’s a recent thread about that, I’ll edit a link to that when I find it.
EDIT:

Ancient veneering techniques and glues are a perfect match for laser cutting!

Veneering might conjure up notions of cheap ‘cardboard’ furniture, but it’s been used for thousands of years to create the many of the finest wooden pieces that litter museums around the globe, and this tradition makes an easy transition to the modern era of laser cutting. Plus, it’s easy, if you know the tricks! So I thought I’d share what I’ve gathered on the topic so far. Examples: [image] Simply veneering a sheet of fancy wood to a piece of laser ply before cutting it can …

With the plies of the exact species of wood we want (or can find ), grain oriented the exact way we want, and the exact choice of natural glue to bond those plies together, we can engineer the optimal plywood to be cut with our visible spectrum lasers.
Keeping in mind that most of those natural glues are animal based, while on the regular plywood the glue (and the in MDF the bonding agent) is most likely (semi)synthetic or petroleum based, often some sort of formaldehyde mix.

Even though it is in theory possible to make MDF the DIY way and to engineer it to be more laser cut friendly, I for one can’t figure out why on earth would someone wish to do so.
I do hate that recycled wasteproduct with a passion.
But that’s probably just me.

Regards,
Sam

[Courtney]

Thank you for all yohr help, i appreciate it