Quality of HD/Lowes MDF? (1 Viewer)

[Mark.Louis]

Greetings, I live about 1-2 miles from both a HD and Lowes and am starting my first speaker project. Is the quality of .75" MDF from these two stores good enough to do speaker building? I will be building GR Research's AV-3s. If not, would a local wood supply specialty store or cabinet shop provide better MDF? Thanks.

 

[darren_s]

The quality of MDF at lowes or HD is fine, you would just pay more $ for the same thing at a local wood supply.

 

[Patrick Sun]

I've built all my speakers/subs with MDF from Home Depot.

 

[Wayne Ernst]

Agreed. HD, Lowes and the local lumber yard probably get the MDF from the same supplier. However, a cabinet shop also will not offer any better quality of MDF, they might offer you more choices. If you needed 1/2" MDF or a smaller quantity than a whole 4' x 8' sheet, then you might look at the cabinet shop. But, the cabinet shop might charge you more than $19.00 for a half sheet of MDF - which is the price for a full sheet @ Lowes or HD.

 

[Jeff Meininger]

Also, Home Depot / Lowes will cut a full sheet down for you so that it will fit into the back of your car. The locations near me do this for free, but their cuts are not quite square which is a bit annoying.

 

[Bob Kavanaugh]

Just be sure to take advantage of the extra inch they give you for each dimension, and trim off those factory edges, even if they aren't dinged. They have been wicking up moisture since the day they were cut.

 

[Mark.Louis]

Thanks for the input, and I will use this MDF.

The last comment about the factory edges concerns me. I don't have a table saw, so my wife bought me the Craftman Accu-rip saw guide from Sears for Christmas.

Essentially, you screw this guide onto your circular saw, and its made so that you guide the saw using the factory edge. It's not like using a clamped straight edge, where you have to measure. With the Accu-rip, you set the distance of the guide to the width of the cut, then use the factory edge (or other edge) to guide a straight cut.

If the factory cut is not straight, then by definition the cut using the Accurip won't be straight. Have you all found good results using a simple clamped straight edge? I know there was a thread a while back...I'll check it out also.

 

[Bob Kavanaugh]

The factory edges are reliably straight, I just don't like having them in my finished work. Your guide system should be fine.

Also to answer your question, I have the 50" true guide (or whatever it's called) straight edge clamp, and have been very pleased with it. I only use it to rough out plywood before I run it through the table saw.

 

[Wayne Ernst]

In the thread that you are thinking of, one of the users here indicated that a sheet metal stud makes a great straight edge for cutting with a circular saw. I picked up such a stud along with two clamps from Home Depot yesterday. The stud was only about $1.30 - most economical straight edge that I've ever seen.

 

[Jeff Meininger]

I built all of my speaker cabinets with a circular saw and a clamped straightedge. What an extreme pain in the butt. The rip guide thing you're talking about should be fine... not to mention easier. The factory edge was _always_ straight, as verified by my big aluminum contractor's square.

 

[Joe L.]

I have found that the MDF found at HD and Lowes is NOT of consistent quality.

At least one time, I purchased 2x4 foot precut pieces of MDF that were very very soft internally compared to other MDF.

These panels of MDF were like compressed cardboard instead of compressed sawdust. Additionally, it was as if it was compressed with too little glue to bind it together. The result was that it split when screws were driven, even when the holes were predrilled.

Unfortunately, I had used some of this for the end-cap of my sonosub. Within a month or so I had to re-build the end-cap when the original poor quality MDF failed (cleaving in half)
The MDF split in half, boy did the sub rattle. Upon disassembly, I could peel layers of MDF off with my fingers. Too little glue... or something.

Joe L.

 

[Dan Wesnor]

I've also had problems with the consistency of MDF from HD. Some of it's more like compressed paper than wood. Sometimes you can tell if it's any good by looking at the edges, but you have to know what to look for. But the only problem it's caused my has been a little extra difficulty when routing out the driver holes, and probably a little bit more wear on the bit.