how
Welcome to our ‘guides’. We genuinely enjoy receiving contributions to the collective knowledge. Please email us with your suggestions.
Feedback we have received has meant some important clarification:
removing
Many original cartridges are over-tightened. This means removing them can sometimes lead to loosening of the tap’s supply pipework. Always thoroughly check the supply pipework once you have changed cartridges.
Only ever use either a ring spanner or a deep socket to remove a cartridge. They come out so much more easily, cleanly and with rarely a problem.
Some TapMedic users remove cartridges using a deep socket on an electric driver. We completely understand why. However, when doing so it is your personal responsibility to carry out a full appraisal of the potential risks each and every time.
An alternative technique to the driver, is to use appropriately sized, and protected so you don’t damage the tap, steel or aluminium pipework slid over the tap spout to hold it steady whilst you remove the cartridge.
Regardless of how you remove cartridges, all supply pipework must be checked thoroughly for leaks once the cartridge is replaced.
seat depth
The seat depth of the new cartridge can never be less than the one removed – otherwise it will leak. Not always immediately, but almost certainly when system pressures rise – probably overnight when pressures rise
When replacing a traditional multi-turn valve with a TapMedic cartridge, e.g. for someone with Arthritis, you will need to measure the original seat depth. The driver has a small silicone ring on it. Use this ring (slide it) to mark the seat depth you need to match. See the video for a clearer explanation.
TapMedic cartridges are designed to cope with being no more than 1mm taller.
installing
TapMedic cartridges must ONLY be installed using either a socket or a ring spanner. Adjustable wrenches have the potential to distort the hex and cause problems/binding. These issues are not covered by warranty.
The shroud adapter, where needed, must be fitted after the cartridge has been installed & fully tested.
The cartridge must be tightened thus:
checking
TapMedic insist the cartridge must be checked at least twice for ‘feel’ before it is considered complete.
Too ‘tight’ to be turned by fingers alone using a 35mm shaft, potentially means early wear/failure.
Too ‘loose’ means a potential for leakage.
Once two or three are fitted, you become familiar with the correct ‘feel’. This is a core reason we consider TapMedic suitable for professionals only
opening direction
The opening direction of TapMedic cartridges are easily changed; simply swap the grub screws. The long grub screw is the one that decides the opening direction. Two must be fitted at all times.
If you & your customer decide you need 360 degree opening/closing, then you simply fit two short grub screws instead of one short and one long.
odds & ends
There will be many cartridges we have never come across in testing. Here we will share those found that can or have been overcome.
Although a 3/4″ ‘fitted’, the seat width was so small the 3/4″ valve would not seal on it correctly. Rather ingeniously, he resolved it by gently using a 3/4″ seat cutter to make the seat slightly wider so the 3/4″ cartridge then sealed properly. All in, it took him an hour to accomplish. His customer was overjoyed and we at TapMedic have learned too. Our customers are clever, caring people. Thank you Roland Keys for choosing TapMedic. Truly the Professional’s choice.This is a 3/4″ cartridge in size but only 1/2″ in performance as its functional side is only of 1/2″ proportions. Roland was called to this one and decided that as it was a built-in wall bath filler he’d use his initiative and engineer a solution rather than have the customer spend out on new.
choosing
The most effective method of choosing the correct spindle is by trying them in the existing handle. If it fits it’s correct!
All too often, one handle will be loose and one tight on the same tap. When you find this, the best way of overcoming it is: Tape does not work as it eventually compresses and loosens. We have found using thin strips of aluminium foil as a form of shim works. It is thin enough to be able to mould, but robust enough not to loosen over time. Until you are experienced, it can be a little confusing deciding which spindle is correct. When it’s too tight, then you feel it ‘almost’ fits – as in ‘lines up’ but won’t go in. Our spindles are made to take some filing down in these circumstances. File a little off the first few mm of the spindle to make sure it will fit. Once it does, trim the spindle to size and then mark the spline length you need to file down.loose?
tight?
opening direction
TapMedic cartridges are adjustable for opening direction by simply swapping their grub screws. The long grub screw is the one that decides the opening direction. However, fitting both at all times is both vital & compulsory. BOTH screws must always be done up TIGHT.
By fitting the long grub screw in the RH hole it will open CLOCKWISE
By fitting the long grub screw in the LH hole it will open ANTI-CLOCKWISE
If you & your customer decide to have 360 degree opening/closing then you simply fit two short grub screws instead of one short and one long. All other issues tightness, number etc are as standard.
A word about our grub screws. Once again, our grub screws are made to our unique specification. They do not comply with DIN916. No formal standard specification could deliver us the very tight and very specific manufacturing criteria we needed. By using TapMedic grubs screws you will remain trouble free with your warranty fully intact.
The cutting jig is supplied with two thumb screws. These screw are designed to ‘help’ hold the spindle or sleeve length you are cutting in place. They are not used when cutting a screw.
Over-tightening the thumb screws will cause damage to whatever is being held.
When that happens, that component is scrap.
The design of the screws is such that they can be tightened appropriately by using only your fingers. Doing it this way holds the piece in place, rather than damages it.
When trimming a handle screw, make sure you thread (screw in) the side you want to be left with.
Doing it like way means that the part you remove (the part you will use) will have to be unscrewed giving you a beautifully clean thread. Warning. The ‘wrong’ way could well mean you having to buy a new jig!
Advice. As most people will use the jig mainly for cutting splined spindles, always draw the hacksaw blade back over the work firmly for its full length before cutting forward. Doing so takes the tops off the splines and stops the blade getting caught up on them going forward. This makes cutting simpler and faster.
With a new hacksaw blade, it should take no more than 12 strokes to cut a spindle – that’s without pressure.
Grub screws (also known as ‘set’ screws in American influenced countries)
Handle Screws
Trimming
The screwdrivers included in TapMedic kits are unique:
When too much torque is applied (we have measured it at over twice what is needed), ‘something’ will give. Normally, it is the internal hex of the grub screws that round out. YOu should apply as much as you can with the flag of the driver held between finger and thumb. Applying more torque to the screws will NOT provide more grip, it will only cost you more money in screwdrivers.
We supply two drivers, however one is all you need to do the job perfectly.
In normal use, we estimate a new driver will be needed after installing around 200 cartridges.
Most cartridges have what we term a ‘handle shoulder’. Its function to to stop a handle with splines running all the way through it dropping down the spindle.
Despite its existence on most, many handles have an in-built ‘stop’ so do not need this external shoulder.
The test to determine whether you need to replicate the shoulder or not, is to try the spindle in the handle. If the spindle goes all the way through then you need a shoulder. If not, then save some money and do not fit one.
See the image for how to mark the handle shoulder position accurately. 1mm higher up the splines (making it longer) is normally acceptable, but cut it any shorter and it may bind.
Often the cartridge you wish to replace has a shroud thread that is not used, not needed. When the cartridge you remove has one that is not being used, why pay to fit a component that isn’t used? To save money and materials, only fit an adapter when it is needed.
Overwhelmingly, shroud adapters are fitted with the thread towards the top. If, however, the cartridge being replaced has the outside edge of its shoulder threaded, then fit the adapter thread down; i.e. thread closest to the cartridge shoulder. This cannot perfectly replicate what was, but have yet to find a customer for whom it was not perfectly acceptable. When you do this, we would strongly advocate changing both so they look the same.