Connecting Sections of Low Profile Rail

A discussion of hardware choices and techniques for joining pieces of thin wood railings. December 26, 2006

I have a continuous over post handrail system to install this week that is a custom profile I haven't worked with before. It is being custom made and I haven't even seen it yet, but understand it is only 1-1/4" tall by 2-1/4" wide with only slightly profiled edges, sort of contemporary design. Although I have installed dozens of stair balustrades, 99.9% of them are post to post and use standard profiles. I am a little rusty on over post systems, but that is not my main concern.

My question is what do you think would be the best way of joining the fittings/rail sections together? I don't believe standard rail bolts will work because of the height (1-1/4"). They might, but the depth of the access hole would be very close to penetrating through the top of the rail. I have considered loose dowels with epoxy, and pocket screws using long screws, but don't know if I am overlooking the obvious or not. I have a Senclamp gun I use for alignment on standard profiles, but the fasteners aren't strong enough to be the sole fastener. The rail is maple with 1-1/4" square painted balusters. There is total of 42 ft of rail and 13 fittings needed for this system. I only have two days to complete the job so I need an efficient way of fastening them. Any suggestions?

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor A:
When working with low profile rail we us planetary or ball fasteners. You can join things as thin as 3/4". One problem is that you will need to make special size plugs for the holes.

From the original questioner:
To contributor A: Thanks, I knew I could count on you. I am not familiar with planetary fasteners.

From contributor A:
Itís a KV product - kv516 joint fastener.

From the original questioner:
Well I feel stupid. I've just never heard the term planetary fastener used for countertop bolts, which is probably the correct term for them. I even have some in my truck, although they're the economy version with the flat plates. But no matter what they're called, I believe they would work. See, I was overlooking the obvious! Thanks!

From contributor A:
The fastener I use for those small profiles does not have flat plates. There is actually a ball that is threaded and mounted inside a ring. It is a KV fitting but I may have cited the wrong number. The dog bone fittings for counter tops may work but covering them would be hard.

From the original questioner:
I didn't mean I was going to use the "dog bone" but that I am familiar with the connector. And you were right on the product number. My normal supplier only carries the dog bones but can get the ball fasteners by the end of the week, which will be too late.

Additionally, I had posted the same question over at JLC and a couple of posters said they used standard rail bolts for low profile rails by using a Forstner bit and lowering the thru hole. So, perhaps I have a couple of choices. If I can't get the ball fasteners in time, I'll just try rail bolts.