From our Archive - Renault FT / TSF - Bolts in the press - Inside Track | Renault TSF Tank Kent

Take a few boxes of 14mm bolts, a fly press, part of a WW2 Jagdpanther and an acetylene welder. Put them together and you have the perfect recipe for WW1 tank bolts. With all restorations we carry out a rough assembly of each vehicle. From this very early stage, however, it was apparent we would not have enough original bolts to complete the final assembly. We managed to restore a fair number and even graft a few heads onto new threads. But we were still approximately 1800 bolts short for the FT and TSF. . Our initial thought was to contract the order out and have the whole lot machined. We were rapidly cured of this notion as the quotes started to roll in. Whilst we were casting about for alternatives, our engineers started to experiment with producing a press tool which might enable us to produce our own. . The first step was to find a piece of spring steel to machine the press tool from. Fortunately we are not short of very high quality spring steel. Lots of it can be found in the remaining torsion bars from of our second Jagdpanther at the top of the yard. Having cut up a torsion bar they machined a section and heat treated the metal to harden and temper it. The tool was then placed in our fly press. The modern bolts were machined to give them a round head. Each bolt head was heated up until it was almost white hot and placed in the fly press. A couple of hefty turns on the press and we had our first prototype. Of course it took considerable adjustments to the tool before we were satisfied with the final product. In the end we went through six generations of prototypes before we arrived at the final version. Each bolt is then sand blasted and trimmed to the correct length. We also had to acquire a new fly press as ours was not up to the job. A quick search on ebay, a trip to Worcester and for £175 we had what we needed. . What intrigued us was how closely our copies resembled the original bolts. We noticed many of the originals had a slight bend in the thread or shank. Ours were exactly the same. We had assumed the French had used a hydraulic press to produce their bolts. Now we were left wondering whether they too had used a hand operated fly press. We will never know for certain but it is an intriguing possibility. Of course what we save in costs we lose in time. We estimate it will take nearly two months to produce the required number.

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