Re: Wood for dials
I have used teak for the base of my sundial. Pictures are on my web site. It is nice to work with but does need care. Wood, if available to the public will end up with "John loves Mary" engraved in it. If I were to want a durable exterior wood I would choose Koa. Hard to work with but very durable. It is used on the bed of trucks and is the prefered wood for that purpose. It is really quite a beautiful wood as well. Not sure if Koa is available in Europe or elsewhere. I believe that its native habitat is Hawaii. Dan Wenger Daniel Lee Wenger Santa Cruz, CA [EMAIL PROTECTED] http://wengersundial.com http://wengersundial.com/wengerfamily
Re: Wood for dials
On Fri, 18 Dec 1998, Jack Aubert wrote: > IMHO, the bottom line on wood-for-sundials is that wood is basically an > unsuitable medium for this purpose, however there are some synthetic panels > which have woodlike properties and may contain some wood that could work > quite well. > > I once stopped to watch a sign being installed over a shop. The sign was > one of those things where the letters are deeply incised as if they were > chiseled into wood. I asked about the material and was told that it was a > type of plastic. It was quite light, and seemed to have about the same > workability as wood. I don't know what this stuff is called, but it might > make an excellent material for a sundial. At least one of these products (sorry, I still don't know exactly what to call it, or ask for) is composed of recycled HDPE(?) milk jugs or the like. It's made into planks of various widths, and used in exposed conditions like playhouses... Dave
Re: Wood for dials
Alders spring up rapidly in riverbank areas and generally grow in clumps -- multiple smallish trunks springing from a single root system. I don't know if this is universally true, but all the alders I've seen are rather small, and I doubt that the trunks ever grow to more than a few inches in diameter. Assuming one wants the sundial to be more than a few inches across, solid wood would have to be either taken from a large tree like oak or maple, or glued up from strips. When large trees are sawn into planks, there are several ways of making the cuts in relation to the central axis of the trunk, and the stability of the resulting boards depend on the orientation with respect to the rings, as well as to the proximity to the center of the trunk. The need for broad panels was satisfied using traditional carpentry techniques in different ways including accepting the wood's movement (i.e. doors build with stiles, rails and panels) and gluing up boards edge to edge with transverse reinforcements (i.e. tables) . Modern woodworking makes extensive use of plywood, where the tree has been "peeled" radially into veneers which can be glued back together (e.g. the ubiquitous and attractive birch veneer plywood... note that birch veneer plywood is 8 by 4 feet but birch trees are rarely more than a foot in diameter). We also now use various types of synthetic wood panels, particularly the different types of "chipboard" which contain a mixture of wood and resin. IMHO, the bottom line on wood-for-sundials is that wood is basically an unsuitable medium for this purpose, however there are some synthetic panels which have woodlike properties and may contain some wood that could work quite well. I once stopped to watch a sign being installed over a shop. The sign was one of those things where the letters are deeply incised as if they were chiseled into wood. I asked about the material and was told that it was a type of plastic. It was quite light, and seemed to have about the same workability as wood. I don't know what this stuff is called, but it might make an excellent material for a sundial. At 03:50 AM 12/17/98 -0500, you wrote: >Dear All, > >>From my time at Kew Gardens I picked up a couple of bits of information >which might be of interest... >Alder, often found growing near river banks or in damp places (at least in >England!), was used for lock gates and also for clogs since it resists the >effects of getting wet and drying out very well. Presumably if it was used >for clogs it must also be fairly durable. > >I have no idea as to the closeness of its grain or its stability, but it >might be worth a try. > >Incidentally, it was the wood of choice for producing charcoal for >gunpowder! > >David Higgon >London > >
Cast concrete?
I have been wondring how hard it would be to cast a dial out of concrete. The technique would require that one make a mold somehow using with raised splines for the hour lines and maybe numbers taken from a plastic sign set or something. I can see how to do this in theory, but have never experimented with concrete casting and I suspect there are optimal ways to dose the sand, cement and water mix.. and there are probably other concrete casting issues. Has anybody tried this? It should be possible to get something that looks somewhat like stone without the difficulty of stonecarving.
Re: Wood for dials
I once had a professor in Design school who said "wood is good", and I agree. I use it for prototypes as well as finished products. I know of very few materials that can actually stand up to freeze/thaw for very long periods. Even concrete will fracture, and most outdoor statuary people recommend bringing pieces in or covering them with a tarp for the worst part of the winter. Here in Cincinnati, Ohio we have very extreme cycles...I have seen it 60 degrees and saturating rain one day, and below zero the next day. My rock retaining walls around the house do not respond well to these conditions, and are a testament to the power of the forces of nature. If you think about it, most of the worlds best preserved outdoor antiquities are in places that do not experience this type of abuse. If you are really bent on using non-tropical wood outdoors, I suggest experimenting with the new marine grade epoxy systems...I use a resin called "epon" by Shell Chemicals. I have not used it in an outdoor setting as described, but I do turn vases and cups/goblets out of various woods and use it to line the interior. Constant exposure to water then has little or no effect, and in fact, the epoxy resin actually migrates into the wood below the surface and forms a polymerized "new" material. However, UV radiation will eventually degrade the surface anyway. But you may wind up with a piece that will last your lifetime at least... Jim Tallman, FX Studios.
Re Wood for dials
A bit tongue in cheek this because I know absolutely nothing about wood and its properties for dials. There is a dial at Downside Abbey (in Somerset, England) which was made a year or two ago by one of the monks from the wood of an old science laboratory bench used at the Abbey School!! This has been carved and oiled (no paint) and when I saw it earlier this summer it still looked fine - however it hasn't been up long enough to know if it is really durable. It is certainly very attractive and unusual though. I can e-mail a picture if anyone's interested. Not sure what sort of wood is involved in old lab benches though :-) Patrick
Re: Re Wood for dials
Patrick Powers wrote > >Not sure what sort of wood is involved in old lab benches though :-) > Very often teak again - especially in older laboratories when it was more plentiful. My garage doors are made from Iroko, often referred to as 'African Teak' or even 'teak substitute', salvaged from more recent laboratory bench tops. Tony Moss
Re: Cast concrete?
Jack Aubert wrote, >I have been wondring how hard it would be to cast a dial out of concrete >...Has anybody tried this? It should be possible to get something that looks >somewhat like stone without the difficulty of stonecarving. Although I haven't seen it for some years there is/was an excellent product called CimentFondu - a high-alumina fine-grained product which is excellent for casting. If cast in a smooth mould the resulting dark surface could be mistaken for patinated bronze (at a distance) and should be excellent for dial making. I remember it being used as a cheap bronze substitute for casting life size figure sculptures. It has one major problem which may account for its reduced usage i.e. unless the mixing is done with the exact amount of water specified by the manufacturer it will 'rot' in time and simply return to powder. At least one new school in Northumberland had to be demolished and re-built because one-site mixing for structural elements wasn't properly supervised. As with many casting processes entrapped air bubbles can be eliminated by pre-coating fine detail e.g. with a brush before final filling of the mould. Vibrating the mould/mix while filling is essential. Tony Moss