Ah. No QRs on my bike. I have, however, slackened and re-tightened the relevant (rear) wheel nuts and made sure the wheel is fully bedded into the frame. Didn't have the impression that there had been much of a problem there, but time will tell. I'll use it a while and then check the pads for uneven wear.
I have noticed that the pads I have been given with the bike are not original Tektro, but a made by a company called WMD and claim to be compatible with my Tektro Novela brakes. I guess that might be the problem, if it turns out they were not made to precisely the correct dimensions.
Thanks for the help.
Tektro don't make brake pads.Neither do Shimano/Hope/Avids etc.They are all made in the same factories,usually in the Far East,then packed up as X,Y or Z.
I have had Disc brakes on MTBs for almost 20 years and have found that some 'brands' are better than others but they are really all much of a muchness.I have never had pads wear like yours so can only assume the Caliper is not in the correct position.This could be Caliper-mount or mount-frame or both.
Are the pads on the other wheel the same?
Re the squealing.Some do more so than others.Sintered pads tend to squeal more than Organic as they are harder so take much longer to heat up.I wouldn't use Sintered on anything other than a serious off-road or downhill MTB.They last yonks but can squeal.
I have only had one set of Mechanical discs,which were Tektro,on my CX bike and with 140mm discs they were OK and never squealed whatever pads I used.