One thing to consider here...and not everyone does...is oil.
When it's clean it does a marvellous job of stopping two parts from coming into contact with one another. The thin,thin film separates the two components and lets them run on it rather than rubbing on one another.
Put a reel together cleaned, but without any oil, and give it a gentle spin......and you won't believe the noise it makes! True, this is exaggerated by the drum of the reel acting like ....well, a drum...and amplifying the noise, but it does tell you just how smooth, or not, those parts that rely on an oil film really are.
I do do this from time to time just to let me know if a bit more polishing might be wise.
Now imagine if that oil, rather than clean, was carrying a bit of grit in it........just how quickly would the reel components wear out? After all, a blob of oil of my knife sharpening blocks is how I sharpen my kitchen knives!
It's this oil film that makes a reel last, and certain designs help the oil do its job, whilst others don't.
The sharp pointed tips of the centrepins from the wooden era of the Slater latch reels just don't support the oil film. Not surprisingly, the oil film shears and the oil dribbles down the shaft to where it does little good.
Hardy recognised this when they made their Conquest reel, and rather than follow the herd they made a big, domed top to the centrepin shaft. They alos made a soft metal section in the spool to ride on the oil film, rather than a rounded screw tip. The curved top and soft metal follower let the oil film remain intact and over a large area and because it was spread over that far larger area than, .... say a Rapidex, the reels lasted a long time between services. I bet they wore horribly if they ran out of oil though...or let any grit in and maybe that is why the Conquest also has a patented release lever designed to also keep dirt out?
Watermole has gone one better!
In some of his more recent reels he's put a fixed ball bearing on the top of the centrepin shaft and a soft metal screw in the spool to ride on it. He's done a better job than all who went before him as the soft screw can be replaced if it wears in a matter of moments.
How good is this idea? Well one well known reel maker is apparently copying it now.......
It's funny stuff oil. I knew one drag racer who had a huge oil pump working the oil around his nitro-burning bike engine...the thing was weeping oil from all sorts of places due to the high pressure...and he kept knocking out the big-end bearings. When he reduced the speed of the oil pump, and thus the pressure, all his problems were over. Which was unfortunate for us as we never beat him again after that........
I hear lots of anglers using all sorts of oils in their centrepins that they feel are the bee's knees. I beg to differ with a lot of them after having to learn about oil film shear strength, sludging and oxidisation the hard way.
What I use now is a fully synthetic oil with hardly any viscosity change at any reasonable temperature which is just as well as it is very thin to begin with. It doesn't stain, it doesn't gum-up and it doesn't let sludge drop out to cause wear. It has the highest film shear strength I've ever heard of and although it wasn't made with reels in mind it does a really fine job in them.
I've got one fishing pal who hasn't ever cleaned or oiled the centrepin I gave him as a wedding present 12 years ago...... ' It has a got a bit noisy lately' he said the other day........