[TryHard]

Two boards are each mitered at 22 1/2 degrees, and I need to glue them together to form a 135 degree angle. The glue joint has to be strong. I have no idea how to clamp them for gluing.

What I mean by "135 degree angle" between the boards is that as you travel along one board, at the joint you take a 45 degree turn.

The two "boards" are really two pieces of a handrail. The cross section is almost round, with one side being flat. (Diameter 1 3/4 inch. Oak.)

How can I clamp these tight when I'm gluing them?

 

[Thadius856]

Have you tried stacking the fat side of a package of shims up against the low point until you build the thing back to about 90º?

 

[DexterII]

Without actually seeing it, the first thing that comes to mind is to lay out and cut a clamping jig out of some scrap plywood or 1x.

 

[Tom Struble]

use packing tape

 

[Snav]

We weld and solder lots of items - a workshop trick is to make your own flexible hinge-clamp . . and then clamp that down to a work surface to use it.

This might be hard to describe . . . try your best to imagine - I'll link to items to use.

1) Short Pan-head bolts with wing-nuts
2) 2 Spring-clamps
3) Heavy Duty door hinge
4) Longer pan-head bolt with a regular nut - MUST be slightly taller than the height of your door hinge.

To make your flexible clamp:

1) Remove the center-post to your hinge - save it for some other use. The long bolt feeds through the hinge in it's place - the nut will clamp it tight so you can control the angle of your hinge and hold it in position. So - be certain that your bolt isn't fatter than the hinge-loops or else it won't fit.

2) Remove the padding from the handles of your squeeze-clamps, there are some holes (one - maybe more). If there are no holes - drill some.

3) Using your short bolts and wing-nuts attach your flexible clamp to your door-hinge . . . tighten well.

Now you have a flexible clamp that can be adjusted to any degree - using ingenuity you can secure it to a tabletop or brace it by any means necessary for hte job you're doing.

When I use this to solder items at my work table I brace the bottom of my hinge-clamp with bricks so it's all heat-resistant.

When my husband uses this setup to weld he uses sign-post metal studs (long metal flat rods with holes all over) and hammers these into the ground outside at the angle he needs and then he attaches the hinge to the top with short bolts and spring-nuts.

 

[oh'mike]

Hand rail sections are typically bolted together--- one section gets a wood thread/machine thread bolt inserted (sorry the name escapes me)---the other section has a mating hole and an access hole under that ---for inserting the washer and nut.

the access hole is covered with a wood plug after the joint is secured with glue and bolt.

 

[TryHard]

Without actually seeing it, the first thing that comes to mind is to lay out and cut a clamping jig out of some scrap plywood or 1x.

Thank you for that suggestion. I can try laying out & cutting a 135-degree form to press against the inner angle of the joint and then spring-clamp that form and the rail pieces together.

I don't know if the nominal miter cuts at 22 1/2 degrees will really be accurate enough to give me a 135 degree angle. So your idea gives me a second idea: I could use the same miter to miter two 2x4s and then glue these together (without clamping) to form a 135(?)-degree form which should match the angle of the mitered railing pieces.

 

[TryHard]

. . . a workshop trick is to make your own flexible hinge-clamp . . .

Thank you for that idea -- I never would have thought of that. I'm going to try to make one of these regardless of what I wind up doing about the railing piece joint.

3) Using your short bolts and wing-nuts attach your flexible clamp to your door-hinge . . . tighten well.

Question: "attach your flexible clamp to your door-hinge" -- do you mean attach the two spring clamps to the door-hinge ?

Alternatively, if, instead, I attached two long pieces of wood about 3/4 inch thick to the two sides of the hinge, I would have an adjustable-angle form that could be spring clamped to the railing pieces. Is that a bad idea?

. . . using ingenuity you can secure it to a tabletop . . .

For what I'm doing at the moment, I shouldn't need to secure the clamped joint to anything.

Thank you again for posting this idea.

 

[Snav]

Yes! So sorry - I did mean "attach your spring clamps to your door hinge" :thumbsup:

Go for the wood-extensions! Sure, why not. The small size of the clamp after you get it put together works great for smaller pieces - nothing wrong with widening the arms to handle larger items, I think it would work just fine like that as long as the wood pieces are securely attach to 2 or 3 of the hinge's holes . . . . . good thinking.

 

[Jackofall1]

To improve the strength of the connection use dowels, this will make a mechanical connection between the (2) pieces.

Mark

 

[Willie T]

You've had suggestions of screws or dowels. This is almost imperative on a handrail.

 

[TryHard]

You've had suggestions of screws or dowels. This is almost imperative on a handrail.

Under normal circumstances, what you're saying would certainly be correct.

However, this case is a little different. The stairway turns 90 degrees; the initial short section consists of 3 odd-shaped steps (none of them has a rectangular horizontal-plane shape). I want a separate railing there. The railing will have two sections: a 45-degree-up section (3 feet), and a horizontal section (15 inches). Each section will be independently supported by its own brackets (2 brackets for each section). The brackets (which I have used elsewhere) are unusual in that they have absolutely no play vertically or laterally. The glue joint is to provide smooth continuity, not strength against pushes & pulls on the railing. I don't think screws or dowels are necessary for this particular case.

And I should admit this: the railing turns 45 degrees at the joint; given the skills I have, there is zero probability that I could drill the holes for the screws/dowels in such a way that the two pieces of railing would fit together correctly.

As for building codes, they differ from one country, province, and state to another. So one might try to bring up the issue of continuity of the railing for different sections of a stairway. For the public buildings in this city, the railings are usually continuous (although often not in such a way that the small continuity sections could actually be *used* by any human with a normal anatomical structure). But I have been in many houses (locally) that have a stairway that turns 90 degrees, and the two railings are virtually never continuous. The customs where you live could be very different, of course.

What I learned from the screws/dowels suggestion is that if I had a multisection railing where some sections needed support specifically via the connection to other sections, I would have to hire a professional. So in fact these suggestions were not wasted on me.

 

[Keith Mathewson]

Glue alone will not hold up over time used in the manner you describe. A dowel will be your easiest option as suggested, use a dowel point to determine the location of the second hole. You can over drill the holes and use 5 minute epoxy on all surfaces then hold the joint until the epoxy sets.

 

[TryHard]

Glue alone will not hold up over time used in the manner you describe. A dowel will be your easiest option as suggested, use a dowel point to determine the location of the second hole. You can over drill the holes and use 5 minute epoxy on all surfaces then hold the joint until the epoxy sets.

OK, I had to Google "dowel point" to find out what that means; but the pictures I found of metal dowel points were clear. But there are problems:

* The two railing pieces are oak, and the oak is hard as a rock. Being able to put enough pressure on two pieces with their mitered ends held at a 45-degree angle to dent the 2nd oak surface will certainly not be easy.

* The two railing pieces have an almost circular cross-section, but with a flat side. The flat sides should line up when the 45-degree joint is made (because otherwise, the flat side of one piece will not flatly contact the brackets). Trying to put pressure on the two pieces (to make a dowel-point dent) while simultaneously trying to insure that the two joint surfaces are correctly mated seems impossible.

However, you said that I could "over drill the holes". If that means that I can drill the holes too big, I suppose that means that my above objections evaporate if the holes can be *substantially* over-drilled. But then:

* If I have a dowel lolling around in substantially over-drilled holes, I don't see how that would result in the dowel providing any strength to the joint even if I drown the holes, dowels, and railing-piece surfaces with epoxy. Why should this create a strong joint?

If I do try this, then:

* What size dowel do I use? (The railing pieces are 1 3/4 inch in diameter.)

* Do I need to find hardwood dowels (oak, birch, or maple)?

* Is one dowel enough?

Sorry for all the questions; you can see I know zilch about carpentry and woodworking.

 

[DexterII]

Not my area of expertise, but I will take a stab at it, and say that I believe that the first thing I would decide is whether I was going to screw or bolt the joint, once it is glued, and to that end, I would try to locate the fasteners that Mike described above, as they provide the mechanics to draw and hold the two sections firmly together. Once I had that determined, I would start laying it out, and decide if I had enough space, but would try to use two 5/16 dowels; starting with regular oak dowel, then grooving it myself. For something like this though, I would make a jig, rather than using dowel points. By jig, I am simply referring to something maybe an inch or so thick, that you could align with a couple of truth marks on your rail ends, and then use as a guide to locate your holes. Points are good for a lot of things, but I personally would find them a bit troublesome for a project like this.

 

[Snav]

When it comes to doweling hard-woods I'd suggest NOT ot use the pointed brads that indent the opposing side to be drilled. While they work great for softer woods - like you think - they don't work all that well for oak.

For hard woods (when doweling) take apart a marker - get the ink-sponge that's on the inside out of it. If it's fat enough you can just put this in one of your dowel holes to mark the other side. Or drill a hole in a dowel - stick the ink sponge in there - and then put that dowel/with/sponge into the hole to mark the other side.

However: I don't rely on these things. I use careful measurements and/or templates . . .I think doing a template will make it much easier to get your drill-holes identical. To make a template: trace the end-silhouette from your rail onto cardboard or stiff paper (even plastic). on the template mark your dowel-holes and punch/cut them out . . . one template can be used to mark both ends the same.

 

[Keith Mathewson]

Lots of opinions to choose from. Here's one that was dowelled in an Ipe rail.

 

[TryHard]

Here's one that was dowelled in an Ipe rail.

That's amazing. There are no brackets added to specifically support that joint. There is no inner bolt, just dowel(s). And you're telling me that that doweled joint can be trusted not to break? (I'm not arguing, I just want to know.)

I know I would not succeed in trying to install a bolt and then a washer & nut through an access hole. But I've thought it through, and using a dowel (or dowels) seems feasible.

 

[TryHard]

. . . For hard woods (when doweling) take apart a marker - get the ink-sponge that's on the inside out of it. . . However: I don't rely on these things. I use careful measurements and/or templates . . .

I feel guilty taking up your time when you're making kitchen cabinets, but once again I really appreciate the extremely specific information you have given.

I like the idea of a template. That I could do, on stiff transparent plastic.

I don't know if you have an opinion on these two questions:

* If I use two dowels, should they be arranged horizontally parallel, or one-above-the-other parallel?

* Why should I use wood dowels rather than brass dowels? Is it just because the glue will adhere better to the wood dowels? (The cost of the brass is not important -- I'm doing only one joint.)

 

[Keith Mathewson]

It works with or without brackets.