This is Nick's full text, in a slightly more accessible format:
LEATHER CARE & COLOUR RESTORATION
This is a guide to caring for your cars leather interiors , I have detailed "˜ how to "˜ and where to purchase products from , which I believe are the best available to the public having tested quite a few over the years.
LEATHER CLEANING & PROTECTION
So why do we need to clean our leather interiors ? The main reason for most people is so it looks good and is nice to sit in ! But to achieve this leather has to be cleaned to remove all the dust and dirt particles which build up on the surface , they act like sand particles and wear away the leather surface removing the protection finish and colour.
We also cause abrasive wear , especially on seat side bolsters , by rubbing against them when getting in and out , so avoid contact of the bolsters as much as possible. This is the most common wear area on car seats.
Clothing dye transfer is becoming a common problem for light coloured leather. It is important to remove ASAP or it can become permanent and recolouring is the only option.
Designer jeans and belts are the biggest culprits so be aware !Keep light coloured leather well protected , clean/reprotect every fortnight. A combined cleaner and protector is recommended for frequent use.
Leather is a natural fibrous material and the moisture content is crucial to stop it drying out and becoming brittle and cracking. All the cleaning products and protectors help maintain moisture but in summer and air conditioned cars it it good practice to wipe over with clean warm water every time you wash the car.( assuming you wash the car once a fortnight or more frequently )
Method
1 - vacuum seats with a soft brush attachment and get into all joints and crevices.
2 - clean using a foaming cleaner , this lifts dirt etc into the foam and then wipe of with
paper towel. If the dirt is engrained use a soft shoe brush to gently agitate the foam ,
More than one cleaning treatment maybe needed. Don't rub hard it will only push the
dirt into the leather.
3 - after allowing to dry apply leather protector to provide a flexible layer of protection.
NB please note wax/oil based conditioners are not recommended. The leathers natural oils are not lost in normal use !
4 - once cleaned to your satisfaction maintain with a combined cleaner/protector and maybe deep clean as above once a year ( depends on use , you will know when it needs it )
COLOUR RESTORATION/RECOLOURING
Whether you want to recolour just a seat bolster or a full seat the method stages are the same.
On older cars the leather colour will have changed due to UV , use etc and a ready mixed colour matched dye maybe different from your leather so it is best to recolour all the leather so it all matches.
BE PATIENT - TAKE YOUR TIME
1 - Vacuum as above
2 - clean as above
3 - surface preparation:
If there are any rough patches gently sand with 800 sand paper.
Small holes and cracks can be filled with flexible leather filler and sanded.
Splits in the leather can be repaired using a backing fabric and filling with flexible leather filler.
If you have a dark coloured leather mix a little dye into the filler so the contrast is less when you start to re-dye.
Then wipe over the surface with leather prep which will remove any finishes/sealants remaining and leave an open surface for the dye to be absorbed into.
Finally wipe over with alcohol cleaner to remove any grease ,oil etc and allow to dry.
The leather is now ready for dyeing.
4 - Dye application - apply at least 2 coats by hand working into the leather and leaving to dry fully between coats. After the first coat the leather will look blotchy and have an uneven appearance , don't worry it will get better as further coats are applied.
I prefer to use lint free cloth to apply by hand , some use sponges. Whichever you use if you feel dragging as you apply the dye stop and reload more dye to cloth/sponge and don't be tempted to go over areas it will drag and create a poor finish.
NB - if the colour has been worn away in some areas put some dye into these areas first and allow to dry before applying first coat to all seat.
Once a even colour is achieved apply 2/3 light coats using an airbrush. Use a compressor at 25psi if you have one , if not the can propellant in the kit will do.
Light coats , start and stop off the leather !
This will give an even colour finish to your leather.
ALWAYS ALLOW EACH APPLICATION OF DYE TO DRY BEFORE THE NEXT ! You can use a hair dryer to speed up but allow to cool fully before next application.
5 - Finish application - spray the finish - 2 light coats - matt or semi matt are recommended.
6 - finally apply the leather protector ,by hand , as in the cleaning section.
Dark coloured leather with scuffing can be successfully treated with a combined dye/conditioner Easy Colour available from LTT. ( see photos on link )
PRODUCTS & SUPPLIERS
CLEANING PRODUCTS
LTT www.lttsolutions.net
Cleaners/protectors/dye removal products/dye+conditioner blend - Easy Colour.
Order on -line or over the phone. Very helpful and instructions for using products are excellent.
I use their products so I know they work.
COLOUR RESTORATION PRODUCTS
LTT as above for cleaners and protectors , cloths ,Easy Colour.
DYNAMIX - www.dynamixdyes.com
Leather dyes premixed to Porsche colours.
When spaying will need diluting to 80% dye.
Don't do a full kit but may in the future.
Contact is Ryan , very helpful.
FURNITURECLINIC - www.furnitureclinic.co.uk
They can supply a full leather recolouring kit ( see website ) but their dyes are not as good as Dynamix ones.
Maybe can supply matched Porsche colours but not sure. You would need to ask.
If they can supply correct colour , without sample of leather , then the kit represents very good value.
May need more coats of dye as not as intense as dynamix ones.
If they can't supply colour matched I would use dynamix dye and the kit from Furniture Clinic apart from the dye.
250 mls of dye will be enough for 2 seats.
A lot of Porsche seats have vinyl sides and backs but the same applies to treating these.
Furniture clinic can also supply repair kits for small holes , slits etc.
Both Dynamix and Furniture Clinic give good instruction sheets.
If I can help please email me with pics if possible via website - www.leatherupholsterycare.co.uk ongoing project . many more examples to be put on.
Will get some more Porsche examples on and examples of what Easycolour can do.
Thanks Nick.
Simon