Ashley Isles split ferrules

[Mister S]

I took some time over the weekend to check for the dreaded rust on any of the edge tools in the workshop (for workshop read garage). I didn't find any rust, but was horrified to find that the ferrules on some of my Ashley Isles chisels had split. Looking back through the forum, it looks like this isn't a new problem.

Naturally Matthew at WH (where I bought them) and Ashley Isles themselves were great, and I will be sending them back for a free repair tomorrow.

Matthew thought the problem was high humidity at some time which swells the wood beyond the point the ferrule can accommodate it. I would have thought so too and it seems to be the prime suspect looking at previous threads on this subject.

What surprised me was the explanation given by Ashley Isles. They blame extreme cold for shrinking the ferrules too much. Although I protect my tools from moisture as much as I can, I haven't thought about cold temperatures before.

I think i will invest in a couple of low energy bulbs for the tool cupboard, to try to stop it happening again.

Just thought I would pass this on in case anybody here has any tools that could suffer in a cold environment.

Steve

 

[CHJ]

.....What surprised me was the explanation given by Ashley Isles. They blame extreme cold for shrinking the ferrules too much. Although I protect my tools from moisture as much as I can, I haven't thought about cold temperatures before.
.....

Honestly that's what they said, unbelievable. at UK temperatures the difference in diameter is going to be a couple of thousandths of an inch at most, I doubt that they can machine the Wooden handles to that sort of tolerance in the first place.
I've had tools with brass ferules accidently left out to get rain soaked and the wood swollen to the point it was bulging either side of a ferule and they have not split.
And I'm sure there is no such problems with my sons feruled tool handles in Bavaria and -20C is not uncommon in his workshop.

Must be some very poor quality alloy they are made from, thought the idea of a ferule was to take any lateral loads applied to the handle and prevent the wood splitting.

 

[Harbo]

I don't think they really know?
I had one go a couple of years ago and they repaired it with no problems.
All my other ones were and are still OK?

My other makes of chisels are kept in similar conditions and non have failed?

Rod

 

[jimi43]

The modern-day equivalent of "cold enough to freeze the balls of a brass monkey".....

Cold enough to freeze the brass ferrules off a nice chisel....

Mmmm...doesn't have the same sort of ring does it?

:mrgreen: :mrgreen: :mrgreen:

Seriously though...once again...this demonstrates the benefit of buying from a very reputable supplier!

....not that I believe the reason either...all my chisels left in the shop have not split their ferrules...neither 100 year old Sorbys or Wards nor ones I have made myself out of brass pipe...mmmm....strange.

Jim

 

[bugbear]

.....What surprised me was the explanation given by Ashley Isles. They blame extreme cold for shrinking the ferrules too much. Although I protect my tools from moisture as much as I can, I haven't thought about cold temperatures before.
.....

Honestly that's what they said, unbelievable. at UK temperatures the difference in diameter is going to be a couple of thousandths of an inch at most, I doubt that they can machine the Wooden handles to that sort of tolerance in the first place.

This appeals the mathematician and physicist in me: here we go;

Assume a large 1" ferrule, so that's around 3.1 inches long, = 7.9 cm, = 0.079m.

From this site we have a coefficient of 18.7 (10^-6 m/m K)

If we assumg a low for the UK of -10 and a high of 40, we have a range of 50. So the movement is:

0.079 * 18.7 * 10^-6 * 50 = 74 * 10^-6 (74 microns)

Something like 3 thou.

BugBear

 

[Vann]

Assume a large 1" ferrule, so that's around 3.1 inches long...

I assume you're meaning the circumference here?

Something like 3 thou.

Again circumference? Not much movement if your maths is correct.

Is the material used for the ferrules too thin? Or does it have a seam that's weak?

Cheers, Vann.

 

[Mister S]

Well the calculation from Bugbear seems to rule out cold temperatures as a cause (by the way-good estimate from CHJ !). A couple have hairline cracks, but the worst offender has a split that's about 1/16th inch wide (can't measure it as it's already packed up ready to send off but there is a pic below). I don't see how that could happen with 3 thou of movement.

There is no obvious seam (on the outside at least) but a few have cracked where the metal has been crimped with what looks like a tap with a centre punch. Maybe this creates a weak spot? I can't measure the thickness accurately, but it's about 0.75mm - it certainly looks thin.

I think I will still go ahead with adding a couple of bulbs to the cupboard to keep condensation at bay in winter. What happens in summer? I seem to recall reading somewhere that humidity is higher in summer than in winter, it's just condensation that's worse in winter because cold air can't hold the moisture. Have I got that right? If so, there is more chance of them splitting in summer!

Or have I made that up? I've reached the age where my brain makes things up but confuses them with memories!!

Steve

 

[CHJ]

That looks like very poor quality material with a very coarse grain structure, more like a poor casting rather than a drawn tube,

If the ferules need to be 'punched' to ensure they stay on then that smacks of very poor fitting tolerance control and not capable of providing, or guarantying the original reinforcing of the handle in the first instance.
Personally I never fit a ferule that is not self supporting enough in thickness to allow a force fit on any terminal spigot.

 

[Racers]

Hi,

I would think they are a tight fit then they push the tang in, increasing the pressure in the ferrule, then in winter the damp gets in expands the wood and the pressure rises, untill some thing gives, either the wood or the ferrule.

Pete

 

[Richard T]

What Chas says.

And that the split is along the line where it has been punched (punched? :roll: ) would point to this line being work hardened and brittle.

 

[jimi43]

Hi,

I would think they are a tight fit then they push the tang in, increasing the pressure in the ferrule, then in winter the damp gets in expands the wood and the pressure rises, untill some thing gives, either the wood or the ferrule.

Pete

I agree with all of the above...it looks more like wood swelling than brass shrinking.

This ferrule (the only one I have a picture of) which I made for a fine turning chisel....

....is a tad thicker...

..is friction fit and has not moved at all in a damp and cold workshop this past year.

Mind you...it wasn't made at a price. Material cost of most metals is making serious inroads into the profit margins of even the finest of tools.

The most important thing is that the maker and the supplier are doing the right thing here...bravo to them both! =D>

Jim

 

[condeesteso]

Are these commercial ferrules a bit thin anyway? I wonder as I need to buy some and have investigated Sorby and Ashley Isles. Any advice on where to get nice thick ones??

 

[Harbo]

I've used AI brass ferrules which I generally buy at Yandles - never had a failure though I've never indented them?

Rod

 

[woodbloke]

I've used AI brass ferrules which I generally buy at Yandles - never had a failure though I've never indented them?

Rod

Same here, I usually buy a small bagful for use throughout the year...never had a problem with them splitting. I fit them to handles so that they'll just push on when squeezed up in the bench vice (obviously some packing under the ferule as it goes on) - Rob

 

[Tom K]

Had three of mine go out of a full set two skews and a little one. Mathew had some replacements sent from AI (couldn't be arsed with sending them back) Think it was a batch of dodgy ferrules from early stock all the others have been fine.

 

[Tony Zaffuto]

Well the calculation from Bugbear seems to rule out cold temperatures as a cause (by the way-good estimate from CHJ !). A couple have hairline cracks, but the worst offender has a split that's about 1/16th inch wide (can't measure it as it's already packed up ready to send off but there is a pic below). I don't see how that could happen with 3 thou of movement.



There is no obvious seam (on the outside at least) but a few have cracked where the metal has been crimped with what looks like a tap with a centre punch. Maybe this creates a weak spot? I can't measure the thickness accurately, but it's about 0.75mm - it certainly looks thin.

I think I will still go ahead with adding a couple of bulbs to the cupboard to keep condensation at bay in winter. What happens in summer? I seem to recall reading somewhere that humidity is higher in summer than in winter, it's just condensation that's worse in winter because cold air can't hold the moisture. Have I got that right? If so, there is more chance of them splitting in summer!

Or have I made that up? I've reached the age where my brain makes things up but confuses them with memories!!

Steve

Can you post a close up picture of the edge of the fracture? I'm wondering what the material is! If it looks like a casting, the material might be powdered metal brass, and if a center punch was used to punch a crimp mark, whereas in typical wrought material that would work, in powdered metal, that would give the potential for a fracture line similar to the one shown.

 

[matthewwh]

It has been an intermittent problem for some time. My personal belief is that the problem comes from the dot, which created a singularity in the otherwise continuous circle. The thinking behind this is that they always tend to go where the dot is, I have had similar issues with knurled ferrules from the same manufacturer and we are now having handles made without any dots or knurling and haven't had one failure. Rod's comment would also corroborate this.

All of the ferrules are extruded, casting would be a more expensive way to make an inferior product, thickness makes no difference (the knurled ferrules were over twice the thickness of the plain ones used on the Holtzapffel handles). I have little doubt that the main root cause is change in humidity causing the wood to move, although low temperature may reduce the elasticity of the brass more significantly than its own expansion and contraction.

Some time ago I asked AI to use undotted ferrules and the last time I checked new production was coming through without dots. The dot is only there to stop the ferrule falling off if the wood shrinks, we have never had a problem with ferrules falling off but if they do it is fixable with a bit of glue, whereas a split ferrule definitely means a trip to the factory.

The slightly grainy look on the outside is lacquer, the ferrule underneath is good quality extruded semi-hardened brass, so hopefully eliminating the dot should resolve this one.

 

[Mister S]

Thanks for the information Matthew, you are in the best position to know about these things, so I'll assume your answer is definitive!

The chisels went off yesterday for repair, so when I get them back, at least I'll know what I'm looking for - no dots!

I'll try to remember to post a picture when I get them back.

Steve

 

[Eric The Viking]

Didn't Hannibal, when taking his elephants across the Alps, modify some of the trickier passes by splitting rocks by driving in wooden wedges and then dampening them?

If true, it must be quite a considerable force exerted when they expand... and the wooden wedges too.


E.



PS: Q: What did Hannibal say when three of his elephants came over a hill wearing big floppy hats and sunglasses?











A: Nothing - he didn't recognize them. (I've already got me coat.)

 

[Mister S]

The force exerted when wood expands due to moisture must be pretty big. The guy who laid my riven stone flags in the garden said he had watched a programme about how they (used to) split the flags. Drill holes along a line where you want the stone to split, drive in wooden pegs that have been dried to reduce the moisture content, then just pour water on them so they swell up.

Split the stone every time.

And if it can do that, my ferrules with dots have no chance...