From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Steering pivot tests detailing the methodology and comparative results.
| Identifier | ExFiles\Box 2\12\ B002_X168-page074 | |
| Date | 2nd April 1913 | |
| From Exp. Dept. Copies to: Mr Johnson Mr Royce Mr Spinney Mr Nadin Re Steering Pivot Tests. - X.160 I am sending under separate cover photo of this arrangement, also photos of the obstacles on the track. This is practically the arrangement suggested by Mr Royce in his sheet MHRB/L12313 except that we are only using one wheel; we tried it with two and fixing our connecting rod to one but we got into difficulty with the wheel turning round. The cross tube has 1.75" movement, we ran it at a speed to give 350 complete reversals per min. The wheel (895 X 135) had detachable rim and weighed 98 lbs. We were very careful to keep the speed the same during all the tests, special care was also taken to keep the same amount of slack in the joints; we had .010" slack in each joint. The arrangement on the whole works very satisfactorily, we can get comparative results of different pivots. Test No. | Type of pivot | Time in mins. start to crack | Time in mins. broken off | Conditions | Remarks. --- | --- | --- | --- | --- | --- 1 | old type | 15 | 25 | straight cross tube | By the fracture it seemed that this was cracked before 2 | old type | 10 | 24 | As above | This also had a crack in it to start with 3 | old type snapped | | 50 | as above | Good fracture 4 | old type | 45 | 71 | as above | Good fracture (contd) | ||