Putting wood screws in Drymax

[rcers]

[font=Tahoma, sans-serif]Still in the market for cargo trailer and noticing that most trailers are using a special plywood called drymax. From everything I’ve read it’s a great material for this purpose. My question is,how well does it hold wood screws? Should I pre-drill the drymax before sinking wood screws into it to prevent cracking/chipping?Gonna be building etrack bunk beds in back of trailer and will be anchoring the etrack to the metal studs as well as the 3/8” drymax walls. Thx for your input[/font]

 

[ratfink56]

Made by Georgia Pacific. Lots of info on their website.

 

[highdesertranger]

if it was me I would insist on plywood. DryMax is OSB, I wouldn't use OSB for anything. this is my opinion and I am sticking to it. highdesertranger

 

[SoulRaven]

screw through the material to the frame, it will not move. so i don't think there's much that good drywall screws can't hold, they can screw into the metal of your van without a problem, wood is easy, etc

 

[user 423]

screw through the material to the frame, it will not move. so i don't think there's much that good drywall screws can't hold, they can screw into the metal of your van without a problem, wood is easy, etc

Right. Hit the 'studs' of the trailer just as you would in a wooden structure. Just buy longer screws..

 

[rm.w/aview]

Yes, I'd predrill with a slightly smaller bit relative to screw size for a better outcome with the OSB board. As mentioned, if there are studs try to use them. Having the mount supported by the floor in some round about way will help relieve stress on the sheer strength of the screws on which you depend. If there are no studs you can install your own which would be floor supported & fastened to the walls providing a good mounting set up & room for insulation. If you're cutting in windows your studs could help with framing them as well.

 

[VJG1977]

I choose to use decking screws with the star drive head, I would not use drywall screws. I know a lot of people use drywall screws for everything but my thinking is that they were designed to hang drywall in a house that does not move or get exposed to water. Even the black coated one are only rust resistant and are not intended for high moisture areas. A better choice would be the Cement Board Screws intended for bathrooms. For the number of screws you will use the cost is not that much more and they will last forever.

 

[Canine]

No sheet material has the strength, moisture resistance, screw-holding ability, and takes paint better than plywood. I used Advantech, which is about the same as DryMax. OSB is OSB and is an inferior product. I'm not saying it is bad, just inferior to plywood. There is also a big jump in screw-holding ability from 3/8 plywood (or OSB) to 1/2 and all you are losing is 1/4 inch of space. Get AB plywood if you can or underlayment; these have fewer voids.

I experimented with various screws and won't use anything but quality screws like GripRite, Rok, GPX, etc. The cheap screws have much less holding ability. No smaller than #8 unless what you are fastening is very light. Preferable #10 or #12. Torx head is the best. If you use phillips, use an impact driver. If you get the correct screw, you don't need to predrill the plywood or OSB. Predrill metal, though.

 

[Weight]

If you have a trailer with drimax. If you need to fasten to the drimax. You should use bolts with fender-washers. Then the bolts are not as likely to pull through. Screws into drimax will not hold.

 

[John61CT]

Weight is a big issue for me.

Can't see using 3/8" anything just for skinning the interior.

Selective structural bits maybe, but I'll try PMF's rigid foam first, metal profiles when needed for load-bearing.

 

[Every Road Leads Home]

As Canine mentioned, use better screws. Drywall screws aren't structurally rated and snap quite easily. As far as i'm concerned they're made to hold drywall up and that's it. You can see how easily they break by screwing one half way into a stud and then tap it with a hammer and the portion sticking out will snap right off. I cringe when I see people using them to hold up kitchen cabinets.

GripRite, Rok and GPX are great and they have the torx heads. I've used torx head screw for years now and using phillips head screws are about as big a pain a flatheads to me when I do need to use one. These brands are available at Lowes and Home Depots so they are readily available.