Description / Prices
Ground screw anchor ("Earth anchor") made of steel, hot-dip galvanized.
EA 10400: length 400 mm, material strength 10 mm, diameter bearing plate 70 mm - Price
EA 12800: length 800 mm, shaft thickness > 12 mm, diameter bearing plate 120 mm, very solid construction, load capacity approx. 250-500 kg - Price
EA 12999: length 800 mm, shaft thickness > 12 mm, diameter bearing plate 120 mm, very solid construction with closed (welded) eyelet, load capacity approx. 500-1,000 kg - Price
Ground anchor for light to heavy loads. For bracing cables, such as free-standing trellises or cables which are attached to rafters. EA 12800 load capacity: 250 kg up to maximum approx. 500 kg (i.e. 1 wire rope 4 mm). The EA 10400 is another option: better for less demanding needs such as securing trees and also for temporary buildings or for where only a small layer of soil lies over rock field. EA 10400 achieves higher separation values when fitting under sod or other dense surface root systems (reinforcing effect). The deeper the ground anchors are set, the higher the holding forces. When heavily used attachments with 4 mm wire rope, where towing loads of 500-1,000 kg per anchor occur, screw EA 12800 10-20 cm below ground level, thus doubling the load capacity. Not for gravel, rocky soil or gravel-bearing soils. Please also refer to our information on eyebolts for support in choosing compatible fittings. (Please know that we assume no liability for consequential damage when using slackline, although we guarantee against breakage!)
First, you need to know whether sufficient ground depth is even available without stone fill (or at least with a few stones or gravel). For assembly, the screw insertion point is marked with a large cross so that the position of the anchor shaft can always be observed and, if necessary, corrected during screw-in by means of the coordinates. The ground anchor is placed on the ground and screwed in by means of a stable rod inserted through the eyelet. Slight pressure from above is required. Using a heavy hammer (mallet), the eye may be struck from time to time in order to facilitate screwing in. The axis of the ground anchor should be approximately identical to the later axis of the tensile load. Sometimes, rubble or debris is in the ground, and this is highly compressed; it must then be pilot-drilled or 'drilled' with the anchor (see photo), but absolutely not to the final depth of the ground anchor. Then insert the anchor in the pre-hole, partially fill again with rubble, then compact this strongly (hit with rammer or hammer); then turn the anchor further. The filling acts as a back support and provides support when finally screwing the component in.
In open land, in a garden, or something similar, the earth anchor can usually be put in without hesitation if it is certain that no electric lines or pipelines are to be found nearby underground. Anytime you are approaching house walls, you must always reckon with something underground. Here, 30-50 cm of earth should be pre-scooped and carefully searched for tell-tale signs of electric lines: cable bands/tape and fine gravel (used when laying the electric cables) are a good sign that electric is underneath. It is sufficient if the screw plate is screwed in 10 - 20 cm deep into the hole; then cover with crushed gravel or similar to weigh it down and cover it. Fill the hole with earth and compress it by clomping it down. This adds to the stability. Mere mud-soil is not optimal.
A Note on Quality and Price...
For price reasons, we previously (for many years) offered earth anchors made of a simple, smooth, structural steel which generally had a stem diameter of 10.5 mm (see product photos). Such anchors are still traded elsewhere. We had problems, however, with the twisting strength (torsional stiffness). If an obstacle appears in the ground (i.e. large stone) and you have been shifting and twisting strongly at the top, the soft shaft twists and deforms and more turning won’t be possible. Standstill! Therefore, we now only use earth anchors EA 12800 / 12999 made of ribbed and pre-stretched (hardened) reinforced steel, naturally hot-tip galvanized.
Made in Germany (Baden-Wurttemberg)