We approached the Talyllyn Railway, the first preserved railway in the World, known affectionately as ‘The Railway with a Heart of Gold, as to whether  any of our services would be of any use to them. The response was a resounding “Yes”. After some brief discussions it was determined that our scanning services could assist in checking the axle box positions & alignment on the Talyllyn Locomotive. The Talyllyn is one of the worlds oldest locomotives still in service & was currently undergoing a ten year overhaul.

At present they use tried and tested variety of measurement tools to check the positions between the axle boxes and this has been done for decades. However, it can take a couple of weeks to get the alignment data confirmed and the Engineers at Talyllyn were interested in finding a much quicker process yet just as reliable as their tried and tested methods.

We visited their workshops in Tywyn & set about 3D scanning the axle box apertures on the locomotive chassis with our Atlascan blue laser scanner. The day was a great success & we left with all the captured data. However, on the night time we sat down and reviewed the day & discussed the method we used. We determined that there was a quicker way to scan the chassis areas but maintain the same standard of accuracy. So we contacted the Engineering team and requested a 2nd visit the following week.

We spent some additional time on setup/preparation but we ended up scanning the chassis much quicker than on our previous visit. Once we had the data we then imported the geometry into Verisurf Metrology software. Verisurf is a metrology software which is so versatile it can be used with the latest and that the movement in the floor was as predicted creating noise on the scan. So our approach was to scan the van in 5 stages and then merge the scans at the end of the process.

The merging of the scans created a root mean square deviation of 78 microns which the client was more than happy with. The client was supplied with an STL file in order for them to do the design work in-house.