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talon2nr7588
05-16-2007, 01:24 PM
how much more does a sheet of 1" mdf weight as compared to a sheet of 3/4" MDF?

ballstothewall
05-16-2007, 01:27 PM
I'm guessing ~30lbs heavier.

bikinpunk
05-16-2007, 01:28 PM
1/.75= 1.33

talon2nr7588
05-16-2007, 01:55 PM
i dont know how much a 3/4" sheet weights.

bjfish11
05-16-2007, 02:20 PM
Its going to vary depending on manufacturer. But roughly a sheet of 3/4 will weigh in at around 100 lbs. 1" would be around 133 from the same manufacturer.

Mr Cabinetry
05-16-2007, 02:22 PM
1" x 1" x .75" piece of 3/4" MDF weight .33 oz
1" x 1" x 1" piece of 1" MDF weight .44 oz

So, add up the total sq.in. of material x .33/.44 ÷ 16 = Weight in LBs.

bikinpunk
05-16-2007, 03:10 PM
Sheets are sold in 48x96x ? in

1in=.0254m

For 3/4" thickness:
0.01875 m^3
1.2 m^3
2.4 m^3
V 0.054 m^3
density 600 kg/m^3
mass 32.4 kg
weight 71.28

For 1" thickness:
0.025 m^3
1.2 m^3
2.4 m^3
V 0.072 m^3
density 600 kg/m^3
mass 43.2 kg
weight 95.04

Once again:
71.28 * 1.33 = ~ 95 lbs.

:)

Mr Cabinetry
05-16-2007, 04:28 PM
Sheets are sold in 48x96x ? in

1in=.0254m

For 3/4" thickness:
0.01875 m^3
1.2 m^3
2.4 m^3
V 0.054 m^3
density 600 kg/m^3
mass 32.4 kg
weight 71.28

For 1" thickness:
0.025 m^3
1.2 m^3
2.4 m^3
V 0.072 m^3
density 600 kg/m^3
mass 43.2 kg
weight 95.04

Once again:
71.28 * 1.33 = ~ 95 lbs.

:)

No way in he!! a 3/4" x 49 x 97 sheet of mdf weights 71 lbs unless it the Ultra Light Weight MDF because I get the info directly from the distributor that has the Manufacturer's Specification Sheets and a 12" x 12" x 3/4" piece of mdf weights 3 lbs.

bikinpunk
05-16-2007, 04:32 PM
No way in he!! a 3/4" x 49 x 97 sheet of mdf weights 71 lbs unless it the Ultra Light Weight MDF because I get the info directly from the distributor that has the Manufacturer's Specification Sheets and a 12" x 12" x 3/4" piece of mdf weights 3 lbs.

That was using the lowest density. MDF has a density of 600-800 kg/m^3 give or take.

How's this:

3/4"
0.01875 m^3
1.2 m^3
2.4 m^3
V 0.054 m^3
density 800 kg/m^3
mass 43.2 kg
weight 95.04

1"
0.025 m^3
1.2 m^3
2.4 m^3
V 0.072 m^3
density 800 kg/m^3
mass 57.6 kg
weight 126.72

?

My point was that it's a simple ratio. 3/4" weight * 1.33= 1" weight. ;)

Mr Cabinetry
05-16-2007, 04:38 PM
That was using the lowest density. How's this:

3/4"
0.01875 m^3
1.2 m^3
2.4 m^3
V 0.054 m^3
density 800 kg/m^3
mass 43.2 kg
weight 95.04

1"
0.025 m^3
1.2 m^3
2.4 m^3
V 0.072 m^3
density 800 kg/m^3
mass 57.6 kg
weight 126.72

?

My point was that it's a simple ratio. 3/4" weight * 1.33= 1" weight. ;)

I understand what you saying, however, most mdf in terms of density hovers in around 3lbs per sq.ft. and the math I use breaks that weight down to the sq.in. weight and it is the most common material sold in HD, Lowes and so forth.

Ultra Light Weight MDF weights in around .22 oz per sq.in. or 1.98 lbs for a 12 x 12 x 3/4 piece.

So, if someone wanted to actually know what their enclosure weighed in at, they could use that math to calculate it.

bikinpunk
05-16-2007, 04:40 PM
While on the subject of UL MDF, what is your experience with it?

Is it simply lighter with no drawbacks in the subwoofer box application?

Also, how much can one expect to pay for it? None of my local stores carry it. :(

Mr Cabinetry
05-16-2007, 06:19 PM
While on the subject of UL MDF, what is your experience with it?

Is it simply lighter with no drawbacks in the subwoofer box application?

Also, how much can one expect to pay for it? None of my local stores carry it. :(

I've used UL MDF to build many enclosure's and to be quite honest I didn't find any kind of drawbacks per say other than the enclosure weighing in alot less than standard mdf.

Though some folks have said they can tell the difference in bass response between the two which is total BS because no one that I have ever made the comparison with the two different material types could tell the difference.

The only other nick picky issue is when mount the sub to the enclosure, the screws tend to strip the UL MDF more easily, but, that can be said for any material if a screws are driven in with to much torque.

It amazes me that all the cordless drills now a days have torque clutch settings at the head of the drill and if people would learn to use them, then they wouldn't be stripping out screws in MDF.

Well, where I get my material from a sheet on UL MDF runs around \$ 33.00 for a sheet of 3/4" vs \$ 22.00 for standard 3/4" MDF and if people would quit buying into all the [email protected] myths about certain materials and their usage for subwoofers enclosure's, then they would save a fews bucks here and there.

bikinpunk
05-16-2007, 06:30 PM
Hmmm, my 967098793 lb box might be going in the trash, lol.

bjfish11
05-16-2007, 06:41 PM
I've used UL MDF to build many enclosure's and to be quite honest I didn't find any kind of drawbacks per say other than the enclosure weighing in alot less than standard mdf.

Though some folks have said they can tell the difference in bass response between the two which is total BS because no one that I have ever made the comparison with the two different material types could tell the difference.

The only other nick picky issue is when mount the sub to the enclosure, the screws tend to strip the UL MDF more easily, but, that can be said for any material if a screws are driven in with to much torque.

It amazes me that all the cordless drills now a days have torque clutch settings at the head of the drill and if people would learn to use them, then they wouldn't be stripping out screws in MDF.

Well, where I get my material from a sheet on UL MDF runs around \$ 33.00 for a sheet of 3/4" vs \$ 22.00 for standard 3/4" MDF and if people would quit buying into all the [email protected] myths about certain materials and their usage for subwoofers enclosure's, then they would save a fews bucks here and there.

Hmm... I would have to say the exact opposite. I never have screws strip out in trupan (Lightweight MDF) but had it happened way back when I used to use MDF.

MikeNeufeld
05-16-2007, 07:33 PM
try medex, it's exterior mdf, they call it in the construction world, it is extremly rigid to flex and does not swell at all with any adhesive.

Mr Cabinetry
05-16-2007, 07:49 PM
try medex, it's exterior mdf, they call it in the construction world, it is extremly rigid to flex and does not swell at all with any adhesive.

I've never had an issue with MDF swelling when using wood glues, so i don't see why I would use a different material(s) for building enclosure's unless conditions warranted using them or the customer requesting them.

Mr Cabinetry
05-16-2007, 07:52 PM
Hmm... I would have to say the exact opposite. I never have screws strip out in trupan (Lightweight MDF) but had it happened way back when I used to use MDF.

I myself don't strip out screws in mdf because I use the torque clutch settings, but, you know as well as I do when folks mount subs to the enclosure, they think they have to tighten the he!! out of them screws thinking there doing something to ensure the seal is tight.

bjfish11
05-16-2007, 09:06 PM
I dont use my clutch settings either, LOL.
However, I do use a deck screw vs. most people using drywall screws. They have a slightly larger shaft and larger threads also I believe. Maybe thats why...