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[Doctor Gollum]

Pretty reasonable all things considered. Certainly it would cost at least as much to buy any other rear wheel drive Coupe that didn't need all that stuff replacing soon. 

[Nick W]

It's Christmas soon, so it must be time for another clapper repair


The steeple-keeper mentioned that when he took the muffles off after Rememberance Sunday, that he though the clapper on the tenor was loose. This is a bad thing, and urgently needs investigating.


None of the relevant bolts were loose, but the clapper had about 8mm of vertical play.


So we loosened the headbolt, and dropped it out the bottom:





The pin is screwed into the clevis, and because the whole thing is 11cwt of vibrating metal, the M20thread  is done up EFT, loctited and has a locknut so a long breaker bar was used with a 30mm socket.


I was expecting to find the either a worn bush, ovalled hole in the clapper or possibly wear in the pin.


I wasn't expecting this:





which is 1" diameter, 20mm bore tufnol sleeve, floating in a 33mm hole - both undamaged. The weird thing is there is no trace anywhere of another bush to connect the two and there's less than 2mm of side clearance for it to escape through. All of this, except for the actual bell, is only 16 years old, so shouldn't be showing signs of wear.


It did mean an easy repair; I machined a new middle sleeve from a (too) big chunk of delrin:





mostly fitted into the clapper







I've reassembled everything, and it all works correctly so we'll refit before Friday's practice.




But I'm mystified by how this happened, especially as none of the other seven bells have this fault.

[Raeturbo]

She gave me water……,🤣🛎

[ronnyd]

It's Christmas soon, so it must be time for another clapper repair


The steeple-keeper mentioned that when he took the muffles off after Rememberance Sunday, that he though the clapper on the tenor was loose. This is a bad thing, and urgently needs investigating.


None of the relevant bolts were loose, but the clapper had about 8mm of vertical play.


So we loosened the headbolt, and dropped it out the bottom:





The pin is screwed into the clevis, and because the whole thing is 11cwt of vibrating metal, the M20thread  is done up EFT, loctited and has a locknut so a long breaker bar was used with a 30mm socket.


I was expecting to find the either a worn bush, ovalled hole in the clapper or possibly wear in the pin.


I wasn't expecting this:





which is 1" diameter, 20mm bore tufnol sleeve, floating in a 33mm hole - both undamaged. The weird thing is there is no trace anywhere of another bush to connect the two and there's less than 2mm of side clearance for it to escape through. All of this, except for the actual bell, is only 16 years old, so shouldn't be showing signs of wear.


It did mean an easy repair; I machined a new middle sleeve from a (too) big chunk of delrin:





mostly fitted into the clapper







I've reassembled everything, and it all works correctly so we'll refit before Friday's practice.




But I'm mystified by how this happened, especially as none of the other seven bells have this fault.

Lovely stuff to m/c. Piles of plastic swarf everywhere. Not like Tufnol, powdery and stinks of burnt piss.

[Marks DTM Calib]

Delrin is a more sensible material choice than tufnol, my only other go to for this application is oil impregnated nylon 6 (which is what we use for brake rigging bushes on the choo choos now).

I would never use Tufnol for that application as it needs regular lube, its more for electrical insulation and can be quite abrasive (hence why it works with lube, it has places to trap oils). I can see that wearing the metal rather than the bush once it picks up a bit of the base to abrade with.

Regarding the original issue, looks like somebody didn't have the correct bush when they were overhauled.......

[ronnyd]

Delrin is a more sensible material choice than tufnol, my only other go to for this application is oil impregnated nylon 6 (which is what we use for brake rigging bushes on the choo choos now).

I would never use Tufnol for that application as it needs regular lube, its more for electrical insulation and can be quite abrasive (hence why it works with lube, it has places to trap oils). I can see that wearing the metal rather than the bush once it picks up a bit of the base to abrade with.

Regarding the original issue, looks like somebody didn't have the correct bush when they were overhauled.......

Used to m/c quite a lot of Delrin in my centre lathe turning days. Not much tufnel though. Machining Magnesium was rather 'interesting', always had the sand bucket handily placed.

[Nick W]

Delrin is a more sensible material choice than tufnol, my only other go to for this application is oil impregnated nylon 6 (which is what we use for brake rigging bushes on the choo choos now).

I would never use Tufnol for that application as it needs regular lube, its more for electrical insulation and can be quite abrasive (hence why it works with lube, it has places to trap oils). I can see that wearing the metal rather than the bush once it picks up a bit of the base to abrade with.

Regarding the original issue, looks like somebody didn't have the correct bush when they were overhauled.......

I was slightly surprised by the tufnol bush, but it and the stainless pin it rides on are still unmarked, round and to size. So is the bore in the clapper, as the original machining marks are still visible. That's why I kept them, and made a new spacer to fill the void. It's delrin because I had some, although I would probably have bought something similar. It would definitely have been closer in size, as I probably spent more time backing the live centre off to clear the long strings of swarf - even 4mm DOC takes time to reduce the diameter from 75 to33mm.


The interesting bit is neither of us can explain what was used before the new spacer, as there is no material anywhere around the bell, frame or on the floor. And there's only a 1mm gap at each end for it to escape through.


As I mentioned, this entire installation, apart from the bells(which vary from 140 to nearly 400 years old), was new in 2006 and has had no work since. It's an entirely conventional modern steel frame using standard parts, replacing the wooden one that was condemned in the early '70s. None of the bells I've seen have lubrication for the clapper pins - access is very poor - and the main bearings tend to get it about once a century . They don't turn quickly, and aren't particularly heavy. The clapper can't swing much more than about 30°. Traditionally, most of these parts would have been made by the local blacksmith, and there are still plenty throughout the country that are still in use.

[ronnyd]

Delrin is a more sensible material choice than tufnol, my only other go to for this application is oil impregnated nylon 6 (which is what we use for brake rigging bushes on the choo choos now).

I would never use Tufnol for that application as it needs regular lube, its more for electrical insulation and can be quite abrasive (hence why it works with lube, it has places to trap oils). I can see that wearing the metal rather than the bush once it picks up a bit of the base to abrade with.

Regarding the original issue, looks like somebody didn't have the correct bush when they were overhauled.......

I was slightly surprised by the tufnol bush, but it and the stainless pin it rides on are still unmarked, round and to size. So is the bore in the clapper, as the original machining marks are still visible. That's why I kept them, and made a new spacer to fill the void. It's delrin because I had some, although I would probably have bought something similar. It would definitely have been closer in size, as I probably spent more time backing the live centre off to clear the long strings of swarf - even 4mm DOC takes time to reduce the diameter from 75 to33mm.


The interesting bit is neither of us can explain what was used before the new spacer, as there is no material anywhere around the bell, frame or on the floor. And there's only a 1mm gap at each end for it to escape through.


As I mentioned, this entire installation, apart from the bells(which vary from 140 to nearly 400 years old), was new in 2006 and has had no work since. It's an entirely conventional modern steel frame using standard parts, replacing the wooden one that was condemned in the early '70s. None of the bells I've seen have lubrication for the clapper pins - access is very poor - and the main bearings tend to get it about once a century . They don't turn quickly, and aren't particularly heavy. The clapper can't swing much more than about 30°. Traditionally, most of these parts would have been made by the local blacksmith, and there are still plenty throughout the country that are still in use.

Do you reckon that delrin might wear a bit quicker, than say PTFE, due to the former being harder? I know that PTFE is worse to m/c as it picks up around the workpiece. Goes like a rotating Christmas tree. 

[Nick W]

Don't know, and didn't consider it as I don't have any.


The original tufnol bush is a push fit in the new spacer which is a similar fit in the clapper, so it shouldn't be a problem. Whatever, it's got to be better than 20kg of clapper clonking about.

[Raeturbo]

Looks a nice job👍

[Sir Tigger KC]

Presumedly when that clapper (or the original clapper) was fitted hundreds of years ago it would have had a leather bush? 

[Nick W]

Presumedly when that clapper (or the original clapper) was fitted hundreds of years ago it would have had a leather bush? 

More recent ones might have been hardwood, brass or bronze. More than five or six hundred years ago, it would probably have just been a hook and eye but we weren't doing full-circle ringing then. The bells were attached to their bearings differently too.

[Nick W]

For some reason I've done a lot of sill repairs lately: 2 MGFs, a ZR and this R100.


The only rot on this R100 is at the rear ends of the sills:







If there had been any other rust in either the inner or outer sills, he'd have been buying new panels as it's quicker, easier and a better repair to replace the whole thing than several patches.


Some basic template and shaping produced these:





Trimming for those exposed this around the rear subframe mount/sill closer:





Which meant another panel





Doesn't get much more basic than this!







Door step and inner attached:







The fully welded job:





I still need to grind the welds that are visible once the sill cover is refitted, and decide how we're going to finish the blend into the wheel arch, as somebody has already filled that far more than was necessary. If it comes to it, we'll dig out all the filler, redo so that the shape is more original(it looks really 'soft' at the moment) and paint the whole quarter panel. It's a five door car, so that isn't a big piece!


And of course, the other side needs the same work.


This job was payment for a ticket to the recent Goodwood Member's Meeting.


Last week I slimmed down all 16 wheel nuts for the wheel adapters to put Scimitar Wolfrace on his TR7 which was a thoroughly tedious job.




I found a long piece of grotty, large angle iron when tidying the garden recently, so this afternoon's job will be to weld three lengths of it to my cheap bead-roller to stop it twisting in use.

[Nick W]

I bought this bead roller about 15years ago when price first dropped below £200:





It's a piece of 10mm thick steel with a slot for the workpiece, and it came with several dies for different beads and steps. The job I bought it for didn't happen and it got abandoned outside for years, which is why it looks like that. As part of my recent Grand Clear Up^Tm, I cleaned it, freed off the seized shafts, replaced the shitty fasteners and moved to sorting one of the inherent issues.


Which is as soon as you apply tension to the adjuster, the plate twists. It twists even more as you crank the work through the machine. That means most of the effort is wasted and the results are really poor. These things are now really common, and all have the same problem. The Grand Clear Up^Tm produced some really crusty angle iron that were fence posts for about 50 years, so it's no use for anything important. But a little cutting and welding later:





The square tube is simply to keep the ends of the slot flat while welding. Before, the plate could be twisted by hand. It's much more rigid now


A sliding rest in the slot will make long straight work easier.


Then a couple of brackets to bolt it to a bench, although a proper stand would be better. Some scrounged gate post welded to a large wheel would work well....






It really needs to be motorised, as large work takes another pair of hands to turn the crank; the favourite for that is a small 12v winch motor and speed controller.


Finally, I'll machine some tipping dies to make starting curved flanges quicker, easier and more accurate. You can buy them, but the £50 they cost will provide plenty of material for several other dies. Making this sort of tooling is one of the reasons I own a lathe.

[dave the builder]

Excellent reading 
I purchased an eclectic metal snotter /glue gun machine a while ago for such sill repairs
fortunately not had to use it yet