plywood deflection rating

I'm building a wall of storage shelving for my 45 record collection (appx. 20,000). The records are stored 200/box and each box is 16x8x9, weighing 15lbs. Will 3/4" plywood shelving 4 feet long support this load without deflecting, each shelve will be loaded to 75lbs with supports on the ends only.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

WOW. Only about 350 45s here. I recently finished transcribing them to disk and burning them to CDs.
Same with the Vinyl LPs.
I haven't done it yet, but I think I'm going to just toss them now.
I'd have to guess about the shelving. I think plywood by itself will always sag. You'd need some solid wood to get stability.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Not an expert on load tables but from what I can understand 3/4" at 4ft between supports would only be good for about 30lbs ??
writes:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yeah, that "sounds" about right.
With a 2' span, it would take 4 times the load to have the same deflection. That's likely the way to go.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I have a work bench made with 3/4" plywood doubled over and supported by metal legs five feet apart.
On top of that bench I have two machine presses that weight about 50-60 lbs each and using them creates a hell of a lot of additional downward pressure.
It's been going fine for thirty years with zero problems.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Some thin metal mounted vertically between the boxes would be a good idea, 4foot is too long a spread to not get a little sagging. Try your scheme, and if there is too much sagging for your taste, a thin aluminum plate would easily fit between a couple of boxes and prevent the sagging.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Toss them??? As in garbage?? Sell em, donate to your church garage sale, Goodwill, anything.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I doubt they have any value. They've all been played a lot. The 45s lack the original sleeves.
Despite the condition, I was able to clean up the recordings I made, sometimes quite well.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
They may sag, and I would provide a strongback along the front edege......You will be amazed how much this helps with rigidity. Strongback like a 1x2 or 1x3..... I also dado the shelves and glue into the sides and make sure to cleat or nail the back. Glue all members..... jloomis

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

There are many different types of 3/4" ply, so there is no one 'correct' answer to your question.
Personally, I'd not expect a 4' span to support that much weight, over a longer term. Eventually it *will* sag.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
They will sag with time. BUT if you finish both sides equally, then you can turn them over now and then.
s

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jeff D. wrote:

Plug in the numbers here and see... http://www.woodbin.com/calcs/sagulator.htm
--

dadiOH
____________________________
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

http://www.stumbleupon.com/demo/?review=1#url=http://www.woodbin.com/calcs/sagulator.htm Enjoy. Tom
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jeff D. wrote:

Other suggestions ok, my $0.02 be to go w/ the 32" spacing for 2 boxes/shelf instead of 3.
If really, really, really don't want to do that for some reason, probably can get by if put a 3/8" back on it (which really would need for stability, anyway) and nail the shelves w/ a 6d finish nail. To make it a little dressier, rabbet the back edges to inset the ply instead of just nailing it on the back.
Will need a back or other lateral bracing whatever size you make them.
--
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I see you've been given a link for the Sagulator web site. If it determines you will get too much sag, there are ways of adding strength. Think of an "I" beam. Adding a strip of wood on the front that is vertical add considerable stiffness. Adding a back and attaching the shelves to it add too. Ed
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It might be cheaper and less work to get steel pre made shelves
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for the suggestions, the sagulator is a great resource. Looks like 3/4 plywood with 2" edging front and back will work nicely. I checked into steel shelving but the cost (discounting my labor) was higher and couldn't find anything flexible enough to fit the space I'm using.
wrote:

It might be cheaper and less work to get steel pre made shelves
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Consider some of the heavy duty shelving at Costco or Sam;s Club. The product looks good, and will easily hold the weight you anticipate. Other sources for that kind of shelving are salvage from store remodelings, often seen on Craigslist or classifieds. Makes sense if your talking storage and not furniture.
Joe
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jeff D. wrote:

JD:
I'm generally with the metal crowd. Check industrial surplus outfits, school surplus liquidation people, take a flyer on Habitat for Humanity stores and try Craig's List. If the first 3 can't immediately help, ask for their suggestions. Used office furniture outlets are often ludicrous. Most industrial/commercial auctions are not good pricewise. Occasionally you will find one with huge quantities of shelving or lateral file cabinets where you can make a buy but you better be in no hurry and live in an urban/suburban locale. Condition and sufficient units of uniform appearance will be your problem when dealing with used material, along with the constant of price .
Plywood on the back of a wood unit is great. So are shelves inset into that backing. On the front, if you can find a reasonable surplus source for heavier threaded rod, you can run that through drilled holes near the front edge using some of the databases you have to elect intervals against sag. Washers and nuts will go on either side of the shelves to tie them into the rod. If this is a decorative effect you fancy, you can also put carefully sawed sections of various kinds of tubing over the rod between the shelves for the coverup pillar effect. The ways you can address this problem are open given imagination and a source of reasonable materials.
Good luck.
Regards,
Edward Hennessey
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.