Alfin drums - fixing srews required ?

[Moliver]

Hello , 

my Alfin drums are fixed on the axle stub with 2 screws. On one of them, the thread is worn, the bolt cannot be tightened anymore.

My techical understanding lets me assume that the screwsts do not serve any essential  technical need as the whole wheele assembly with the wing nut will hold the assembly in place.

Cab this assumption be confirmed ? 

 

Cheers

Oliver

[John Morrison]

Correct 

John

[Lebro]

Not sure about Alfins, but with standard drums I had assumed this for a while until I noticed that the holes which the wheel studs go through are somewhat larger that the wheel stud diameter, so without the two locating screws the drum could easily be not centralised. It's true that once the when nuts are tightened the screws are doing nothing further.

Bob

[BlueTR3A-5EKT]

The peg on the spline adaptor face locate the drum.   The screws hold the drum in place for adjusting the brakes when the wheel is not fitted.   Once the split cone and wheel are fitted and tightened by the spinner ( wing nut) the brake drum is completely secure.

[John Morrison]

It's true my experience is with steel drums, but you can run these without the screws.

Can't see why you couldn't run Alfins without or adjust the brakes without this fixing.

John.

[Lebro]

Did not notice that these were for wire wheels !

Bob

[BlueTR3A-5EKT]

18 minutes ago, Lebro said:

Did not notice that these were for wire wheels !

Bob

Yes, hence my comments about peg and split collar.

The other issue with the countersunk screws is that they must be low enough head profile to seat below the face of the drum.    Any old countersunk screw may have a thicker head than original requirement and be too tall.   This is why Cox & Buckles, latterly Moss had the correct screw made years ago.   Rationalising stock to use the MG item on a TR was wrong for the reason stated above.

[Hamish]

I seem to remember my alfins weren’t counter sunk for the location screws  

so I did it to ensure the screws were properly recessed.

may be run a suitable tap into the threads to clean them up ?
 

[stuart]

Its usually the screw that strips the thread rather than the hubs, a change of screw may improve matters.

Stuart.

[Nobbysr]

On 5/20/2023 at 9:56 PM, Lebro said:

Not sure about Alfins, but with standard drums I had assumed this for a while until I noticed that the holes which the wheel studs go through are somewhat larger that the wheel stud diameter, so without the two locating screws the drum could easily be not centralised. It's true that once the when nuts are tightened the screws are doing nothing further.

Bob

pretty much on the money Bob   lthough there is a different style with the fins in line with the brake hub   but they secure the same way with two scres

[Lebro]

True for steel wheels, or wire wheels on adaptors I think, but the early wire wheel hubs appear to use the 4 "pegs" (as Peter says) to centralise.

Bob

[BlueTR3A-5EKT]

50 minutes ago, Lebro said:

True for steel wheels, or wire wheels on adaptors I think, but the early wire wheel hubs appear to use the 4 "pegs" (as Peter says) to centralise.

Bob

Correct.   3are the length to suit the thickness of the drum.  The fourth is longer to allow location of the half round cut out of the split taper cone,     The wheel when tightened compresses that split in the  taper and the half round cut out grips the drive peg and the centre diameter of the split taper grips the spline adaptor. .   All rather ‘boot strap’ really with each part holding the other in place.