There is a separate section on the marking out of lawns and the adjustment of hoops.
A croquet hoop comprises two vertical uprights joined at the top by a horizontal crown and must be provided with a means of anchorage at the base of the uprights. In cast metal hoops there are carrots at the base of the uprights for achoring. A set of croquet hoops (for the Association or International rules game) consists of 6 hoops. The Laws of Association Croquet put the following constraints on the design of hoops (Law 3b)
- SPECIFICATION Each hoop is made of solid metal and consists of two uprights connected by a crown. A hoop must be 12" in height above the ground measured to the top of the crown and must be vertical and firmly fixed. The uprights and the crown must have a uniform diameter of 5/8" above the ground although minor deviations at the top and bottom are permitted. The inner surfaces of the uprights must be approximately parallel and not less than 3 ¾" or more than 4" apart (subject to Law 53(b) for tournament and match play). Each hoop on a court must have the same dimensions within a tolerance of 1/32". The crown must be straight and at right angles to the uprights.
- COLOURS The hoops may be left unpainted or coloured white and, in addition, the crown of the first hoop (hoop 1) is coloured blue and that of the last hoop (rover) is coloured red...
In addition the tolerance is specified and for manufacturers there is a specification for getting hoops approved by the Croquet Association (CA). Each country has tournament regulations which specifies the gape for hoops for use in its tournaments (CA hoop regulations).
As a rule of thumb the total gap between a ball and the hoop uprights should be only 1/8" (which is the thickness of a pound coin).
Types of Hoops
 Comprehensive collection of hoops courtesy of Archie Peck, NCC, Florida
Photo: Samir Patel |
There are three basic hoop types to consider:
| Cast/welded metal | ~£170/set |
| Metal tube or thick wire hoops | ~£60/set |
| Wire hoops | ~£20/set |
Cast/welded Hoops
Only cast or welded metal hoops are suitable for tournaments. They are generally made of iron, but some aluminium ones have been produced. Aluminium hoops are easy to carry where the hoops have to be set out and lifted daily but offer little resistance to the passage of the ball. Both sorts of cast hoops are brittle, and should only be knocked into prepared holes in the lawn. Hoops should never be treated like chest expanders - they will snap. Cast hoops are available to Championship size (3 3/4" gape matched to +/- 1/32" on a single lawn) or President's Cup size (3 1/16" + 1/32"). Both have 5/8" diameter uprights. Hoops can also be manufacted by welding the correct diameter stock together. These tend to be stronger than the cast hoops.
The tangs or carrots
which go in the ground should be solid and not a simple 'X' cross-section.
The latter are not solid or heavy enough and hence are not recommended by the
CA. Note that if you are buying a replacement hoop, the spacing of the carrots
can differ from one manufacturer to another. Some hoops have the carrots concentric
with the uprights, others offset. If you have any odd hoops in your set you
should paint these as Hoop 1 (blue crown) and Rover (red crown) so that they
are always placed in the same holes on your lawn to cater for different carrot
spacings. Some companies provide a hoop drill which is a cast iron set
of carrots at the correct spacing which can be pounded into the ground to prepare
it for the hoop.
Currently Aldridge, Jaques and EDT (Omega) are known to sell hoops in the UK. These hoops are available from the CA. Avoid the older Jaques hoops which have the 'X' section, non-recommended, carrots. Other of the listed manufacturers may well sell hoops. Most companies are cheaper than Jaques. It is possible to buy hoops which are white plastic coated but I have no experience of these.
Hoops that have current Croquet Association Approval are as follows: Omega Adjustable Hoop (Steel; Standard and Championship Approval, December 2000) and Jaques Championship Hoop (Cast Iron; Standard and Championship Approval, July 2005). The EDT Omega hoops have rotating eccentric carrots which allow the gape of the hoop to be adjusted with a spanner once the hoops are in the ground - see the patent (requires the Acrobat viewer). The Jaques have solid carrots and consequently are stable during play.
There have been recent recommendations of the 'Aldridge hoops' made from welded steel with oversize carrots produced by Bill Aldridge of Bowden Croquet Club (UK), who should be contacted for further details.
In America welded stainless steel hoops are available (see illustration). Hopefully stainless steel hoops with solid carrots will soon be available in the UK. Hoops are tedious to paint!
Cast iron hoops are not particularly strong and will snap if they are pulled apart or stuck too heavily with a hammer. Hoops should be painted regularly otherwise they will corrode and weaken. A small external pit will hold water and lead to a sizeable defect after time. The hoops should be stripped every three years or so with paint stripper then red lead primer or similar corrosion inhibitor used as undercoat. Normal gloss paints are suitable for the final coats. It is also possible to have hoops sprayed with plastic powder (see Renovation section below). If you have more than one lawn you can paint the carrots of the hoops different colours to indicate which set should be used on which lawn. Some clubs additionally number the hoops so that they are always put in the same holes.
Finned Hoops
Finned hoops are used principally in America on very sandy courts. The length of the carrot and flare and number of fins is matched to the conditions. In sandy soil (at the NCC, Florida) hoops like (a) above worked loose very rapidly. The 4-finned hoops (b & c) were more robust for longer. However the large flare of the fins and their thickness caused a bump around the hoop due to the displaced soil. Of the two 4-finned varieties the ones with the 'X X' pattern (b) were prefereable as the '+ +' pattern (c) caused the turf to split in the centre of the hoop in use. The finned hoops are inferior to the solid carrot hoops in play and would be unsuitable for any court which had any stones in the top soil. They are also very difficult to adjust.
Tube and Wire Hoops
The tube hoops are made from 3/8"-1/2" tube and look better than the thin wire ones. Wire hoops run from 6-10mm diameter. The wire or tube ones are fine for all aspects of croquet except for proper hoop running practice - you can always blast a ball through these hoops.
If you get tube or wire hoops I strongly recommend that you paint the lower part of the hoop which sticks into the ground a different colour, leaving 12" of the white hoop protruding above the ground. It gives people a hint of how much of the hoop should protrude above the ground. If this is not done you find six inch high hoops stamped into lawns. Red oxide paint is ideal for the part in the ground and will give some corrosion resistance.
Renovating Hoops
After a season's play the hoops may need some attention. The main problems are: bends in the uprights (bowing) and battered paintwork. Note that bare metal hoops are now allowed by the Laws
Bowing
Cast iron hoops are are brittle! They will snap if hit ,struck hard or over-stressed. The bowing is best cured by pressing the leg or crown of the hoop in an engineer's vise or press. The vise allows highly controlled application of force and, if required, small lumps of sacrificial wood can be added into the jaws to slightly 'over-bend' a bowed section so it returns to straight. The wider the mouth of the vise the better. No attempt should be made to lean on or hit the part of the leg protruding from the vice.
Removing Paint
The usual domestic methods can be used - paint stripper, scraper, sandpaper and wire brushing. The latter two are hard work and paint stripper expensive, but easy! Although a long job a metal scraper is very efficient in removing the majority of the paint. I doubt whether a blowlamp or heatgun would be effective due to the large heat capacity of the metal - heating the hoop to a point where the paint burns off may affect the metal's subsequent properties.
The preferred method of removing paint is 'particle' blasting as this leaves raw metal in its wake. There seem to be subtle differences between sand, grit, shot, bead and soda blasting. Sand blasting is credited with giving a good raw surface for coating and grit blasting leaves a less deep 'orange peel' effect than bead blasting.
Priming
The purpose of priming is to inhibit corrosion, improve adhesion of the top layer and improve the surface quality. Some surface coatings however can be applied directly to the raw metal (e.g. spray coating followed by baking). There are various primers, but the choice of primer is dictated by the final coating. Corrosion inhibitors include hot (metallic) zinc plating and/or primer coats (a yellow, acid-etch primer coat, preferably a two-component pack for zinc. Subsequent coats of paint will not adhere to the zinc without the acid etch). Red, yellow and etch primers are cited. In Oxford a couple of coats of 'red oxide primer' are used.
Top Coat
A couple of coats of white gloss paint are perfectly acceptable for the top coat. Emulsion does not wear at all well and should be avoided. We have tried 'Hammerite' but found it too brittle. We have not had the facilities to try proper stove enamel. The trendy coating method at the moment is powder coating. Powered coating uses electrostatic attraction to draw paint powder to the hoop and the hoop is subsequently baked to fix the paint. There are a number of varieties of paint which can be used: epoxy, urethane and polyester. Polyester is recommended as being impact and UV resistant. It also has the best corrosion resistance of the three. Epoxy paint is also available as a 'two pack' product and can be painted onto the hoops. Epoxy is claimed to be the least UV-stable of the coatings.
Costs
Commercial costs for having hoops sand-blasted and spray coated are in the region of £3.75 - £5 per hoop (2001).
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