request for info - joining wood end-to-end

[Roger Barga]

I'm seeking advice on the best way (stength-wise) to join two pieces
of wood end-to-end.


The LOML has asked me to replace the railing on the stairs in our house. It has seen better days and I have never like the fact the previous owners painted the wood a dark brown, especially when everything else in the house is cherry or maple. I thought it would be a one or two day project at first - construction is a simple 1" thick piece of wood that is 2.75" wide. But I measured and it's a 12 foot long single piece of wood and there are only two brackets holding it to the wall (each a foot or so from the top/bottom). I'd like to use cherry or figured maple but doubt I can find either of these woods in that length. So, I expect that I will need to join two sections of wood together. My question is what is the best way to join two or more pieces of wood together end-to-end so that I have a sturdy railing when complete, especially considering it will only be anchored near the top and bottom.

Thanks in advance for any advice,
Roger

PS - if anyone has built railings and would like to offer design tips or photos, I am open to suggestions.

[Alan Turner]

I am not a stair builder, but I would think that if an end joint is needed, a scarf joint might be the strongest. Don't know what part of the country you are in, but in Pa. we can buy 12" cherry, maple, including figured, without any problem. If need be, you might consider mailordering a long enough board,as a stair rail is pretty importnat in terms of strength.
Alan

[Bob Smalser]

Scarf your joint at 8 units of length for every one unit of thickness and join with gap-filling structural epoxy like West System, MAS or System 3 available at marine stores. Get the high-adhesive thickener and instruction book that comes with it.

The fastest method for one man to cut a scarf joint at the end of the 12' piece of stock is to lay it out with a bevel, cut it with a hand saw close to the line and plane to the line with a hand plane.

You can also build a simple 8:1 jig of tapered plywood built into a box and clamped to the workpieces to do this with a router and an end mill.

Either way, the gapfilling glue variety makes a strong joint foolproof. Just make sure you thoroughly saturate that endgrain with glue before clamping up.

[Todd Burch]

Roger, you could start with a 12' long piece of oak or other commonly available hardwood for your area, and wrap it with cherry or maple veneer. I guess you could even strip the one you have and wrap it.

I think I would add additional supports regardless, especially around any mid-span joint. It seems, even at 1" thick, you would get some flex in the handrail over the 10' or so span.

[Steve Cox]

I would think a 12' long board would not be that hard to find. That would be your best solution. If you wind up needing to join the boards a scarf would be best. Bob above described one scarf joint which I learned as an "airplane scarf". The one problem (for me) with that joint here is that the taper would show on the edge when you sand the board. For boat handrails I learned to use an "anchor scarf" also seen under other names where the joint goes in at 90 degrees to the edge of about a quarter of the distance then you cut the angle. This leaves a less visible joint.

[Dan Gill]

I would think a 12' long board would not be that hard to find. That would be your best solution. If you wind up needing to join the boards a scarf would be best. Bob above described one scarf joint which I learned as an "airplane scarf". The one problem (for me) with that joint here is that the taper would show on the edge when you sand the board. For boat handrails I learned to use an "anchor scarf" also seen under other names where the joint goes in at 90 degrees to the edge of about a quarter of the distance then you cut the angle. This leaves a less visible joint.

Steve, I am having a hard time picturing this. Perhaps others are, too. Do you have an image of this, or a drawing for us poor illiterates? :D

[Roger Barga]

Thanks everyone for helpful advice. I can see right away I was on the wrong track, as I was looking at different router bits and had not considered a scarf joint (heck, I may have heard about this one in shop years ago but it is the first time I've ever used it).

I tried our local sources for 12' to 14' cherry and no luck, and ordering it will incur some nasty shipping charges because of the length. Anyway, I'll order up some nice figured cherry lumber (standard size) and practice a few times while waiting for it to arrive. If I round-over the top of the railing, I can see how the anchor scarf would look a bit better.

Again, thanks everyone.

[Gary Max]

Why not just build it out of several peices of wood ----offset the joints and use 1 inch stock 8 foot long to build a solid beam. This would have to be more solid than a one peice of wood.
Just a thought.

[Steve Cox]

I keep tryiing to upload a picture of the difference between the two scarfs but I'm having difficulty. Anybody want to tell me why every time I try to upload I get a "page not available" error?

[Bob Smalser]

Camera is at the shop so I can't make you a picture.

What we're calling an anchor or stopped scarf isn't the easiest one to cut if you've never done one before.

Looks like a 1:8 feathered scarf 'cept the feathered ends are clipped off.....so it can't be planed along one straight surface. A sawcut is made about a quarter thru the thickness at the inboard end of the scarf....then the planed faying surface runs from the bottom of that sawcut to the end of the workpiece....then that end clipped to match the sawcut. Has to be planed crossgrain by hand after cutting on the bandsoar, so you'll need a shoulder plane.

I'd recommend the easier feather scarf I mentioned before. There is no glue joint that can't be hidden with a little attention to staining and clouding during the finishing process.

http://www.cianperez.com/Wood/WoodDocs/Wood_How_To/Smalser_on_RestoringVarnish.htm

[Todd Burch]

I think this is what Steve is referring to. (I think)

[Todd Burch]

Actually, in the looks department, this second one is better looking.

[Dan Gill]

Thanks for the replies from Bob, Steve, and Todd. Todd, the pictures say it all.

[Lee Schierer]

Roger, the local lumber dealer I work with has Cherry and Maple hand rail and Maple Wall rail. I don't know where you are located, but if you want to talk with them send me an email and I will give you their telephone number.

The other concern is that a single piece of wood supported only at the ends with 10 feet between the supports is not going to give you any real strength if someone is falling and grabs the railing. I would strongly suggest at least one more hand rail hanger in the middle of the span for proper support and strength.

Here is at least one place that sells Cherry railing in the legth you want.Hand rail (http://www.stairsupplies.com/index.asp?PageAction=VIEWCATS&Category=22)