Buying a used lathe - What is important?
Investing in a used lathe can be worthwhile. The purchase process should be carefully planned and the price well negotiated.
Buying a used lathe or turning lathe can be an economical alternative to purchasing a new machine. However, the lower investment costs only come into play if the machine concept really fits the intended machining behaviour and no major compromises have to be made.
In contrast to a new purchase, not only do one's own requirements play a role, but the market offer must also be taken into account. As a rule, major compromises have to be made, which is why prioritising requirements and defining exclusion criteria are important in the selection process.
When does it make sense to buy a used lathe?
The decisive factor is the intended range of workpieces in terms of material, dimensions and quantities. From this, not only can a rough technical specification be derived, which later also forms the basis for the search for a suitable machine model, but the question can also be answered quite quickly as to whether the search for a used machine makes sense at all. Because if the performance parameters are not "average", the search can either take a very long time or too many compromises have to be accepted.
Also, the lower investment costs should not tempt one to proceed less meticulously. Otherwise, a machine may be purchased quickly, only to discover that, due to the inhomogeneous range of components, economical operation is hardly possible and the unit costs are far higher than when a specialised contractor is commissioned.
Choosing a used lathe - What to look out for?
In the best case, the machine is still in operation and can be inspected "under chip". In any case, a comprehensive documentation of the machine history and maintenance measures as well as a current inspection report with the corresponding measurement protocol should be available. Especially if it is not a machine that has been overhauled by the manufacturer's factory or a recognised specialist dealer and is sold with a warranty or guarantee claim.
On a lathe, a possible reduction in quality is reflected in a deterioration of the working accuracy and surface quality. Especially if a high output quantity is to be achieved, it is important that the machine still produces reasonable results even in the limit range. Mechanical wear occurs on all components where there is surface contact under relative movement. This not only affects the direct guide surfaces, but also all other bearings, shafts and gears.
If a lathe is overhauled by a specialist company, an acceptance report is usually drawn up. The usual inspection points also provide a good indication of what to look for when buying a used lathe. Regardless of whether a conventional lathe is to be purchased second-hand or a CNC lathe is being sought. The condition of the mechanical components is essential for the subsequent working accuracy.
Lathe, conventional lathe or CNC lathe
The different designations result from the degree of automation:
In the case of a used CNC lathe, it is of course necessary to check separately whether the control technology installed is sufficient or whether adjustments are necessary.
Buying a used lathe - Which price is justified?
Although some trading portals for used machine tools exist in the meantime, there can be no talk of a transparent market, since on the one hand offer prices and the purchase price actually paid are far apart and on the other hand the number of machines with comparable condition and property values is simply far too small at a certain point in time of valuation.
Therefore, a market price cannot simply be used, so that an attempt must be made to determine an appropriate market value for the lathe.
Due to the limited market transparency, the approximate current value of the lathe must therefore first be determined. The current market value is the value of a machine or plant taking into account its age, operating condition as well as the average period of use and service life. The basis for the calculation can be the acquisition or new value; in any case, a reasonable value should be assumed that comes close to a fictitious current purchase price. This value of the lathe is then to be corrected downwards with the help of the utility factor or the degree of condition. If external reference prices are used, care must be taken that apples and oranges are not compared and that in both cases a value for a naked machine is available. This means that a certain amount of value must also be deducted from guarantee claims.
When determining the condition of the lathe, it is advisable to consider the value shares of the different assemblies. Gearbox, headstock and motor have a value share of 50 -60%. Components that obviously need to be replaced should be deducted at the equivalent value of a professionally carried out repair.
A reasonable discount factor must also be determined for work quality and remaining service life. It also makes sense to include energy consumption if power consumption and efficiency are worse than on current lathes.
In the end, the price determined in this way should be in a range that makes the purchase appear attractive. It is difficult to give a general guideline, as current supply bottlenecks for new machines can drive prices up. However, buying a second-hand lathe involves a number of risks that are only worth taking if the return on the total investment is optimally higher. Therefore, the discounts should rather be somewhat more generous.
What else is there to look out for in a used lathe?
Very important and always to be considered when buying a used machine. Before recommissioning, it must be ensured that the new lathe meets all the requirements of the Ordinance on Industrial Safety and Health. If an upgrade of the control system or other components is planned that fall within the scope of substantial modification, the requirements of the Machinery Directive also apply. This is because it also applies to machines based on used machines that have been so substantially modified that they can be considered new machines.
In each individual case, it is determined whether new hazards emanate from the changes made to the lathe or whether existing risks are increased. Accordingly, three cases can basically be distinguished
In the latter case, suitable remedial measures must be defined and a new risk assessment of the lathe must be carried out.
Sources of supply for used lathes
The purchase of a used lathe and it should be checked whether the dealer also offers a maintenance and repair service or whether it is purely a machine broker. In the latter case, it is advisable to call in an external specialist company or expert.
In the meantime, however, more and more renowned machine manufacturers have buy-back programmes for their own machines, overhaul them and then offer them again as certified used machines. A look at the corresponding offer pages can be worthwhile in any case.
Used lathe - How much can I save?
In order to assess the cost advantage of buying a used machine, it is not primarily the purchase price that is decisive, but rather the utilisation behaviour. The higher the planned utilisation of the machine, the less the one-off purchase price will matter. In order to get a realistic picture, higher repair costs should also be assumed and a certain risk surcharge due to no or lower warranty services should be added. Energy consumption is also a significant cost factor that should be taken into account in any case. Disassembly, packaging, transport, installation, modifications and commissioning often have to be organised by the customer in the case of a used lathe, which can also greatly increase the cost price.
If the machine is in good condition and fits your own requirements with a few exceptions, then the operating costs can be 5 - 10% lower, but this is paid for with greater planning uncertainty and possibly worse financing conditions.
