Kia Ora Toutou
I have been working on some Western red cedar doors for my shop for a while. A bit of a waste of time as it’s a tin shed, but they have been both a lot of fun and a challenge.
Now nearing completion, I have hit a tiny snag…
The doors are coach-house style, with a glazed upper section and a tongue-and-groove lower panel, taking up about 2/3 of the height of the door, and separated into two panels by a curving member which runs between two opposing corners, in the manner of a brace, but curved.
I have carefully cut thinner cedar planks, tongued and grooved to fit the gaps, and tongued to fit into slots on the supporting members, and it looks pretty good, though getting the planks straight and cutting the complimentary curves was a nightmare. Next time I’ll build a jig rather than using templates…
When I come to glue up though, I face a problem. I am allowing a 2mm gap between the planks (they are 90mm wide so this should allow for even the most extreme wood movement – the cedar is bone dry right now)
How to fix the boards in place though.
I don’t want to glue them together as that would create massive gaps at the edges, and with the curved shape there is only room to move one way, but I can’t allow them to float either as they will over time shuffle to the lowest point.
My options so far considered:
1. a dob of glue in the centre of each board where it contacts the supporting timbers. There are 19 boards to each panel though as well as some large timbers so that would be a bit of a gnarly glue-up, even using polyurethane.
2. a pin nail in the centre of each board – I will cover this with a decorative 6-8mm bead (1/4″ to 5/16″)
3. a pin nail at the ‘top’ of each board – this means the board will only move one way, but I can control which way it moves, which may be advantageous with the curved groove.
I have a finish nail gun but it may split the boards even so.
Your thoughts welcome on how to fix panels like this and the best way to glue it up. I’m favouring the glue method for fixing as I dislike nails, but of course if anything goes wrong I’ll be there all year with the acetone cleaning it up.
Any tips on finishing cedar doors also appreciated – I have a variety of tones as I bought some stock that had been wrongly milled at a very low price to make my T&G. I don’t mind variety and have in the past left my cedar projects unfinished, but the doors will be against galvanised steel so I’d prefer a less rustic look. I’m thinking to stain all of it with a cedar coloured stain then some sort (advice…) of suitable finish. The doors get sun from mid morning to lunchtime. My climate is sunny and the UV is exceptionally strong.
Any and all advice gratefully received
Nga mihi
Rob
Replies
If I deduce that your goal is to keep each individual board in a predetermined location while still allowing for seasonal wood movement I think the only viable solution is pinning each slat top and bottom in the predetermined location. I would pin them using stainless nails predrilled from the back. Your pin nailer and standard nails may indeed split the boards but would almost be guaranteed to create rust stains over time.
FYI and I hope this does not occur but a lap joint would have been better than a tongue and groove since wood can swell across its thickness as well causing the T&G to wedge and bind. You may be best served by pinning every other or every third board thus allowing the boards to move in small groups in case a particular T&G joint does wedge tight yet still achieving your basic goal of keeping the slats in a general location.
Thanks. I think pinning in batches may be best as you suggest. I'll be covering nail holes with trim anyway.
I would also pin them in the center top and bottom on the back side. A 23ga pin will not split the wood. I have used this method on Cedar shutters among other things and it works fine. A spot of glue on the indent and lightly sand will fill. Stainless pins/fasteners are required. Steel and galvanized will react with the wood. I have also on occasion fixed them with wood pegs. Cut square lengths from your straight grain scraps (maybe 1/8- 3/16") then trim them to an octagon cross section. Router table works well if you have a bunch to do. Drill a stopped hole from the back glue, drive in.
https://www.fastenerusa.com/nails/stainless-steel-nails/finish-nails/23-gauge-micro-pins/1-2-micro-pin-nails-23-gauge-304-stainless-steel-1m-minipak.html
Thanks. Getting stainless pins may be a challenge! I am not in the USA
McMaster's may ship to New Zealand, I believe that's where you call home, or there is always Amazon. They may be worth a try anything other than stainless steel will leave unsightly stains in short order.
I have found an NZ supplier and they also sell really nice 23ga guns - an excuse to buy a new tool is always welcome. Thanks for your support.
A couple of things came to mind as I read your query, 1., while they're curved, there must be a way to shave a little more thickness off the tongues to allow for swelling, and, 2., are those little round rubber balls I've seen offered as a way to keep raised panels centered in frame and panel construction available in your area? Just more grist for your problem solving mill.
Space balls would be ineffective on this scale, but a small diameter backer rod, maybe ¼", would probably be helpful. If you are not familiar with backer rod it is compressible foam rod sold in rolls in various diameters that is used to fill large gaps often before applying caulking. It has since been adapted to various other uses where a compressible material is needed. The most easily related application being around the perimeter of floating LVP and engineered wood flooring installations.
Thanks - I have allowed some slack in the tongues - there is not likely to be an issue with the thickness changing - It's the width that is a problem - the doors' shape means that the annual expansion and contraction will tend to push the slats away from the curve. A spacer might be an option - I am using 2mm cardstock at the moment to ensure an even look, but though a really good idea, spacers would have a few issues - I would have to trim each tongue individually to ensure precise alignment and then glue the ball in place prior to assembly - I have a fair few boards in each panel and planning the glue-up is going to be a challenge. I like the idea of not using pins, but in the end using spacers is so much harder that the pins will win.
Also with pins, I can glue the main joints, which are very hefty 6" half-laps or 4" wide by 2" deep floating tenons and then shuffle any panels that are out of place around a little until it all looks even.
It would have been much easier to have built faux braces, but in the end I wanted to practice the complimentary curves, and the doors will be a lot stronger for what difference that will make - now paying for it!
I was thinking just use the backer rod around the perimeter not each slat. It might provide some support to the panel while still allowing expansion.
Please post some pics when it's done. It sounds like quite and undertaking.
This forum post is now archived. Commenting has been disabled