Gate Hurdle making for beginners (not hazel wattles)

[ToneWood]

I was quite taken by the hurdles featured on this video http://www.youtube.com/watch?v=2Bl1HQg7aCo
I have a need for a piece of rustic fence, maybe 10ft long - to block off a sudden drop at the end of footpath. A custom section of hurdle might be just the ticket and it would probably suit the location well (as the area is quite visible), unlike modern alternatives. It'll likely need to be custom made (perhaps by me), as the path will it be at one end, next to a wall - so it will be unsupported/cantilevered at that end, i.e. it will need to look something like this (as I'd rather not screw it to the wall):


H -|-------------------|----------
e -|-------------------|----------
d
g .. Flower-bed....... Footpath. Wall
e

I'm thinking I might be able to get some chestnut. What size tenons would something like this typically require? Should I just drill them & then clear them with a chisel? (I'm new to tenons)

I met a greenwood worker at a fete a couple of years ago, he made some fantastic looking cleft chestnut gates - using a similar approach and materials to the hurdles. The gate would have really suited our home too but I couldn't justify purchasing one as our current metal gate, which is nothing special to look at, is at least 50 years old and with occasional painting could easily last another 50. He also had some really interesting examples of rustic 5-bar gates, rose arches and rustic trellises too - all very much in keeping with the area and using a similar approach/materials. Maybe I should give him call?

[emjay]

Don't give him a call. Get some chestnut and have a go. You don't know what you're capable of until you've tried. Mortice and tenons aren't too hard to do and on a hurdle they don't have to be perfect.
As Gavin would say, "post some pictures"
Mick

[jrccaim]

OK, fence sections. Traditional way is to make fence mortices with a twybill. If you google on twybill you will find lots of references. But do not be too concerned with tradition. I do not know what cross-sections you propose to use. Let's say 30cm /12". A fence section is basically a bunch of mortice-tenon joints. Now, I hasten to add, you could just nail the d**d crosspieces in place. But I will assume, from the fact that you went to the trouble to ask this question on Bodger's, that you don't want to do that and good on yer, mate as the Australians say. Bravo. Mortise and tenon it is. Hard part of an M &T joint is making the mortice. I find the easiest way to make a M&T joint is this: drill some holes about the size of the mortice, or a little less, along the the sides of the mortice. The more holes the better. If you were doing 30cm poles, 12 mm holes should be more than enough. Then chisel out the rest of the mortice. I used to do mortices with nothing more than a morticing chisel. No more. Drill the things out. If you are really good with a chainsaw you can plunge-cut the mortices, but I would not under any circumstances advise this for a novice. No, drill and chisel. The tenon is much easier. Saw it approximately to shape. Shave it down with a chisel if you have to. Much easirer to shave a tenon then to enlarge a mortice!

It really helps if you have a morticing chisel the exact size if the mortice you are trying to make. But it is not essential. I have made dozens of M&T joints with nothing more than ordinary carpetenter's chisels. It really helps if the chisel you use does not taper, because tapered chisel = tapered mortice.

[ToneWood]

Yes, I keep coming across Twybill's - odd looking tool. I'm finding it hard to picture somebody using one of those to cut a mortice. Would like to see one in action. Ditto a mortice axe/hurdle-maker's axe.

Yes, if I do the fence, it will use mortices and they will have to look good (or at least be attractively rustic!). Drill sounds like a good idea. I just have a cheap hand drill but I would think that is good enough.

30cm posts? Is that a circumference/diameter? The posts that I am thinking of would likely be smaller than that. It'll need to be fairly lightweight in appearance and contstruction - more like the posts feature in the coppicing video. Did you mean 30mm - so that a 12mm mortice would be a little more than a 1/3rd of the width?

[ToneWood]

The rustic fence has been put on hold - pity, I think it would look good and allow me to learn a few new skills without "biting off more than I can chew" - I failed to convince the wife/gardener/landscaper/boss, so far. I think she pictures heavy "square" horse fencing, rather than slim, rustic, cleft wood. She liked the sheep hurdles & rustic gate pictures I showed her. However, she suggested a couple of other projects: some hurdle-like rustic coarse trellis to act as a "wall"/separator in the garden & to support plants (this might well be "biting off more than I can chew") and/or a new rose arch. I'm not so keen on the rose arch, wooden arches & cheap metal arches fail in my experience - a simple, tall, strong wrought/welded iron/steel seems like the best policy, as the plants will cover it and it will need to be buried deep to withstand wind gusts (& a local farmer/friend offered to make me one). Also, it seems rather complex for a first cleft wood project.

Looking for a simple, effective design for a break/brake, to allow me to split wood. I have some potential material: several single-sided pallets, a very big heavy-duty double-side pallet, some hardwood tile crate sides and 2 long pieces of 4" sycamore each with a crouch.

[See Brake thread: viewtopic.php?f=5&t=2424]

[ToneWood]

I've got some birch in, various sizes some quite thick (pity it isn't ash, I could make axe handles). I'm wondering if I could use birch and/or sycamore riven, instead of sweet chestnut/ash, to make my hurdle-like trellis/rose arch?

Sycamore (a.k.a. great maple) doesn't seem particularly well regarded in the UK - but in the USA maple seemed to be prized, not least for figured (flame/quilt/tiger striped) guitar tops and some necks.

[Brake info. moved to brake thread, see below]

[ToneWood]

New brake thread: viewtopic.php?f=5&t=2424

[ToneWood]

New brake thread: viewtopic.php?f=5&t=2424

[ToneWood]

I'm hoping to assemble my cleft birch into a gate-hurdle-style trellis, which will act as a separating "wall" in the garden. The (currently vague) plan is to make something 4-5' tall + 1.5' to be buried into the flower bed. I've found an image of something similar that will act as a rough model for this although I don't plan to copy it slavishly and mine will need to be much wider (which may not work ).

Basically it will be an extra long hurdle turned 90 degrees, so the long side is vertical. The original thought was that the horizontal posts top & bottom would contain mortices for evenly spaced long vertical posts. Additional cross-pieces (horizontal & diagonal) would be nailed on with galvanised nails (apparently copper nails are used by some - not sure if they have any advantage over galvanised, perhaps more resistant to tannins or perhaps they were used before glavanised nails became available?). It occurs to me now that this trellis may need to be as wide or wider that it is tall, so perhaps a more conventional hurdle orientation would make sense. Either way, getting the basic design sorted and then making all those mortice & tenon joints are likely to be the main challenges - I've never cut a proper "square" mortice & tenon joint before, let alone in cleft wood, so this will be interesting. Gulp.

[81stBRAT]

Tone
One thing Birch loves to do is rot if outside but good practise for next time
Richard

[ToneWood]

Thanks Richard. Pity. Come to think of it, I vaguely recall reading something about birch - perhaps in the context of firewood - having a high water content which makes it susceptible to rot, the article might have suggested bark removal. It's been particularly wet this year (to be expected with the Diamond Jubilee AND Olympics here I suppose ), which won't help. The wife asked me to make this gate-hurdle-style trellis but has already commented that she doesn't think it will last (& I haven't started making it yet, beyond riving the wood!). Judging by the wind gusting through the garden this morning, & your comment, she's probably right. But, as you say, good practice. I suppose I can always use the debris as firewood next year.

I found a chestnut supplier, maybe 30 miles away, who I think would likely provide me with a decent amount of wood for my £. It seems extravagant to drive 30 miles each way just to get wood. Maybe if I go that way for some other reason, I'll contact him again. Somebody told me that they harvested their chestnut by arrangement with the Forestry Commission nearby but perhaps I misunderstood, as they traveled in from 15-25 miles away (in a different direction). I haven't yet been able to find any info. on this - so perhaps it was a special arrangement. I heard the FC nearby lost their contract earlier this year.

[Davie Crockett]

Mods, I apologise if this is off topic and it may warrant a thread of it's own, but reading this post prompted me to have a look at natural means of preserving timber to stabilise it or make it suitable for outdoor use, so first stop was Wiki where I found this article: http://en.wikipedia.org/wiki/Wood_preservation

Under one of the headings was Acetylation, which reacts the Hydroxyls in the wood with Acetic Anhydride (a major component in vinegar). Basically it stabilises the wood by preventing the uptake of moisture. (Hydroxyls are responsible for absorbing and releasing moisture when the ambient air is damp/dry).

The process has never been viable as a commercial venture (Patented 1930) But in a lightbulb moment, I wondered if it would work on bowls/hurdle stakes to prevent warping and reduce rotting in damp conditions. I'm no chemist so shoot me down if it sounds absurd.

Snipped from Wiki:

The physical properties of any material are determined by its chemical structure. Wood contains an abundance of chemical groups called free hydroxyls. Free hydroxyl groups readily absorb and release water according to changes in the climatic conditions to which they are exposed. This is the main reason why wood's dimensional stability is impacted by swelling and shrinking. It is also believed that the digestion of wood by enzymes initiates at the free hydroxyl sites - which is one of the principal reasons why wood is prone to decay.[9]
Acetylation effectively changes the free hydroxyls within wood into acetyl groups. This is done by reacting the wood with acetic anhydride, which comes from acetic acid (the main component of vinegar). When free hydroxyl groups are transformed to acetyl groups, the ability of the wood to absorb water is greatly reduced, rendering the wood more dimensionally stable and, because it is no longer digestible, extremely durable. In general, softwoods naturally have an acetyl content between 0.5 to 1.5% and more durable hardwoods between 2 to 4.5%. Acetylation takes wood well beyond these levels with corresponding benefits. These include an extended coatings life due to acetylated wood acting as a more stable substrate for paints and translucent coatings. Acetylated wood is non-toxic and does not have the environmental issues associated with traditional preservation techniques.
The acetylation of wood was first done in Germany in 1928 by Fuchs. In 1946, Tarkow, Stamm and Erickson first described the use of wood acetylation to stabilize wood from swelling in water. Since the 1940s, many laboratories around the world have looked at acetylation of many different types of woods and agricultural resources.
In spite of the vast amount of research on chemical modification of wood, and, more specifically, on the acetylation of wood, commercialization did not come easily. The first patent on the acetylation of wood was filed by Suida in Austria in 1930. Later, in 1947, Stamm and Tarkow filed a patent on the acetylation of wood and boards using pyridine as a catalyst. In 1961, the Koppers Company published a technical bulletin on the acetylation of wood using no catalysis but with an organic cosolvent[10] In 1977, in Russia, Otlesnov and Nikitina came close to commercialization but the process was discontinued presumably because cost-effectiveness could not be achieved. In 2007 a London-based company, with production facilities in The Netherlands, achieved cost-effective commercialization and began large-scale production of acetylated wood.

[ToneWood]

Pickle the wood with vinegar? I've heard of Fuchs before (maybe Peter Follansbee's side axe?)

[ToneWood]

I made a first pass at the gate-hurdle trellis today. Surprisingly the thing I was most dreading - cutting the mortice slots - was fairly straightforward and very enjoyable. The tricky bit what cutting the tenons to be in the same plane . I ended up busting one of the tenons later - cut it too wide/applied to much force inserting the tenon for the 4th time.

I've installed the basic frame (just 2 uprights with 2 horizontal bars morticed into place) for the wife to evaluate. I nailed the tenons into the mortices & use nails to hold the damaged mortice together - well, it was a first attempt.

Chisel cutting the mortices
I drilled 3x 1/2" (/12mm) holes for each tenon, then used my cheap, plastic handled 1" chisel (which is now honed to a polished finish & extremely sharp) to cut the sides. I got to use my little 1/4" vintage Marples register mortice chisel for the first time, to clean-cut the ends - although it was not the correct size (1/2") for the job it proved to useful and was a joy to use. Bear in mind that mine are rough-cut slots for v. approximate axe-cut tenon* - any carpenter would laugh at them. Never the less, I was very pleased with them and smiling away at the end of the task . The broken mortice later wiped the smile off my face - but I'm happy enough with the result for a first attempt.

Axe cutting the ground spikes & tenons
*Started off using Pa's 2lb chopping hacket for the ground spikes, which is now v. sharp. However, I felt the need for the tighter angle afforded by the asymmetric grind of my Swedish carving axe, which felt noticeably lighter. The asymm. carving axe make short work of the ground spikes and tenons -- although adjusting the tenons so that they were aligned with each other (despite the twist in the wood) proved frustrating & rather time consuming - the adjustments often made things worse rather than better.

The comment somebody made about hurdles mainly being damaged due to moving them rather than rot makes sense to me now. Mine is certainly not up to the quality of a professionally made sheep hurdle, that used to be carted over the hillsides.

[ToneWood]

The wife just got back & likes the prototype trellis . I've got to move it though (which may destroy it), after she has moved a few plants.