More bed rails...

[chopnhack]

Well the time has come for my eldest to graduate to a big boy bed! Luckily we bought the crib that converts to a full size bed with the addition of bed rails. Unfortunately when I called there seems to be a 18-20 week lead time to receive them??? Are they really that busy? Anyways, the price was fair at $89, but I simply can not wait that long. As LOML says, he will be in college by the time they ship :P

So.... My thought was to use some of that new PureBond plywood from BORG.
It looks to be lumber core ply. The glue is remarkably strong, I remember seeing a segment on a nature program some years back on a marine biologist studying mussels and how they "glue" themselves to the rocks. The scientist isolated the proteins the mussels used to anchor to the rocks and found a way to make a synthetic version using soy! The program showed him boiling squares of plywood made with this glue with no delamination and no strength changes either.... genius stuff!

Anyways, the product is now available and my question (finally) is should I laminate two 1/2" pieces to make 1" thick rails or can I safely get away using just a 3/4" piece of ply on edge 5-6" wide for the rails. I would finish the top with a piece of hardwood capping, something like a 3/4" square, chamfered, that would be attached via a dado to the top of the plywood. The attachment method is the two hooks that rest on two steel pins that are embedded in both the head and footboard.

Your thoughts and comments please

[cabinetman]

So.... My thought was to use some of that new PureBond plywood from BORG.
It looks to be lumber core ply.

Lumber core plywood is exactly that. It's also called "blockboard". Its core is from lumber strips (not necessarily hardwood). Its features are that it's very flat and very light, but not significantly strong, IMO. I use a lot of it as I like some of the features of having a solid wood core (when needed), and not veneered layers.

I would rather use a good veneered plywood, like Baltic Birch, or Apple Ply. Even some of the Maple ply that I get from my suppliers is very stout, has no voids, and has full 1/16" face veneers.

For a mechanical fasteners, a tapered connector like this one holds well. To. compensate for end grain holding power, you could edge glue solid wood (long grain). That would give excellent holding power.
.

[cgallery]

Is there a reason you'd prefer not to use solid lumber?

[vanguard]

Since your working on side rails for a toddler bed, I think you'd be fine with 3/4". I'd be more worried about lateral strenght then vertical, but if you putting a ledger at the bottom for slats to hold the matress, I think you'd be fine.

[chopnhack]

Interesting point Cman, I thought that the plies were longer "sheets" of thick veneer but the blockboard pic you have linked shows it to be nothing more than edge glued lumber with veneers on either face. I think we are looking at two different products though...The blockboard pic had only one internal layer. The reason I am using the hardware is because the bed has the pegs existing in both head and footboard.

CGallery, I looked at doing red oak 1x for the rails, but figured since I will need rails for son #2 in the future, why not get them made at the same time and that is why I was thinking plywood. I can get all four rails from a sheet of plywood. I know that the rails of my king size bed are plywood with an oak top rail and the mattress weighs quite a bit.

Is there another more economical choice than red oak that is readily available that I can stain to match a reddish chestnut color that anybody can suggest?

[JimD]

Ash has figure like oak and is less expensive when you can find it.

The equation that determines deflection of a beam treats the vertical dimension of the rail to the 4th power if I remember right. It is much more important than the thickness. If you use something with a relatively low resistance to bending, like plywood, and do not make it real thick, you can compensate by making it taller. My decision on thickness would be driven more by the fastener. You need enough thickness to hold the joint with the metal pieces. If you use a piece of softwood 2x2 to support the slats, it will also help stiffen the rail significantly (even though it is not tall). Even softwood is stiffer than plywood.

Jim

[chopnhack]

Out of curiosity Jim, do you have that formula? That would be nice to check the size requirement of the rails before building. My first thought was to use a smaller piece of ply (about 1 3/4" wide) glued and screwed (1" #10) to the rail on the inside to support the slats and cutting a 3/4" recess so that the slats would be flush with this inner support.

The pins that lock the hardware in place are 1" long so the plywood would be shy on the inside. The only reason I am being a slave to this hardware is because the bed is already setup for it and there is a slot right where I could have installed a bed bolt or some other type of hanger.
Thanks for the recommendation of ash.

[drumpriest]

I was going to suggest looking it up on the sagulator, but it appears to be down at the moment. I'd give it a try tomorrow though, it's a shelf sag calculator. Anyway, I suspect you could get away with 3/4 ply if you do a couple of things. We just bought a bed (sad, I know, but I've just got NO time), and the sides are only about that thick, with a ledger for the slats, as you have shown. The clever bit is the slats themselves, they screw to the ledger, and in the middle that have a leg that goes down with an adjustable foot to go to the floor. So the bed weight is only supported on the sides by 1/2 of width of the mattress, and in the center it's supported by those legs. As they won't be seen they can be made from 2x4s or poplar as a secondary wood. I think ours are poplar.

[chopnhack]

Yes, I have seen that on my own king size bed (center supports). I didn't think I could use the sagulator though on plywood. I will have to give it another look. Thanks for the input. I was thinking last night of just laminating two 3/4" pieces of ply and resolving the whole weight bearing and pin location issues. Thanks again all

Edit: Thanks Keith - there was a fir plywood entry at the bottom that I missed, with the depth and thickness reversed a single piece of 3/4 ply over a 78" span at 5.75" wide can hold 680lbs before deflecting 0.02" Pretty impressive figures.

[chopnhack]

An update on the build 3/16/2010

To date the materials for building the rails have been sourced, purchased and cut to size. I am now making some scrap test pieces to ensure a good fit of the hook style fastener for the bed rails. The last thing I want is to have an ugly gap where the rail meets the head and footboards. I have two sets to build, one for each child. The cribs are from the same manufacturer, but the factory's tooling setup was different for each crib and so I will have to adjust the depth and height for each one individually. On one crib, the metal fasteners fall right into place, the other one.... lets just say someone was in training that day! The slot is not deep enough or tall enough to allow the metal fastener to fit into the slot! I had to thread a coping saw blade through the slot and carefully cut the slot higher. A lot of fine tuning that should not had to have been done. On the plus side the little guy is excited to see his crib becoming a "big boy bed"

It would be near suicide to attempt to free hand the slots on the edges of a 6"wide x 3/4" thick x 78" long piece of plywood so I thought a jig was in order. This is the best I could think of to do this particular operation and all thoughts on better options are welcome.


Jig for making the slots. Top piece is the stop for the circ. saw. I was thinking about adding a side piece once I establish center line on the first piece. After that I can add a scrap of the same materials thickness to index the work. (I realize this pic makes the plywood look bent, but I assure you its a straight piece right off the t.s.!)



One complete test piece.


Positioning for drilling holes.


Section view of slot


Jig in action. Sorry for the bad shot, but trying to hold the saw and take the photo was difficult when I realized the clamps were off!


If there is interest in the build I will continue to post otherwise I will stop since this is a trivial project and not any real woodworking

[cobob]

Be serious. This isn't an everyday project & has 'out of the box' thinking. Of course I'm interested

[chopnhack]

LOL, fair enough. As long as I am not talking for the sake of taking up bandwidth or boring anyone, I will post.

Today I made all 8 slots in the rails. The jig helped alot, but the things I would have done differently would have been to have more room on the left hand side to allow for indexing and slots in the rear pieces to allow for easier positioning of clamps. I forgot to account for the size of the saw's shoe. I wanted to be able to screw down some scraps to establish the first centerline and then add a thickness to index me to the next slot to be cut. oh well, the idea was good.

In the softwood plywood test fit, the rail fastener seemed to go in snug, but just right, while in the hardwood it was too tight and I was afraid of splitting it. Apparently the softwood construction plywood compressed enough while I was inserting the fastener on the test piece! I cut a rectangle of some aluminum flashing, sanded the edges to take the burr off of them and not slice myself silly, wrapped some 60 grit and started the process of sanding the inside of the slots. I have 4 slots fitted and 4 more for tomorrow.

I got the expert advice of how to match the existing cribs for the rails from one Mr. Jeff Jewitt. Anyone know him?

Here are pics of the crib. The colors he recommended using were reddish brown and golden brown transtint.

Hopefully tomorrow will be another productive work day

[chopnhack]

Finished fitting the slots on the rails. Started making some test samples using transtint dyes. Managed to assemble one rail with 3/4" thick red oak top to hide plies. I chamfered a 45 along the length between the plywood and oak on both pieces to obscure any irregularity in their joining which I intend to later darken with stain and toning. I doubted strongly that the two will ever look similar so why try to match them up

Should I be using the 3:1 and then try to tone it ? If you see the second pic, the 1:1 seems to match the top fairly well, but in other places the 3:1 mix seems to bring out the orange more in other places of the piece. The first lower test square of 3:1 surprised me as it got great color, is this because of sanding the spit coat with 320?

Methods: Sanded board using 150, 180, 220 raised grain with water and sanded when dry with 220. Sealed lower 1/2 of board with 2:1 water to hi perf using foam brush(ran out of sponges). Gently sanded dried, sealed area of first spot only with 320 grit (didnt seem necessary on others as they were smooth). Top coated with one coat of GF Hi Perf. Satin. Very minimal amount of stain lifted when top coated.

From left to right (top half unsealed, bottom half sealed with 2:1 mix of water to General Finishes High Performance)

3:1 golden brown to reddish brown
2:1 golden brown to reddish brown
1:1 golden brown to reddish brown
3:1 golden brown to reddish brown over darker colored streaks in plywood







I would have done more but I had to entertain my helper and when he got tired I asked if he wanted to sit down and he said yeah, daddy make me a chair lol
But he helped me assemble it and he wanted to sand it.

[chopnhack]

Was able to sneak up on the color some more and I think we are ready for sanding then staining