Also someone had asked about the cross tension on the BLX that FabFed posted. The sticker indicates the tension is 22.5 (49.6lbs) so the cross tension is 21.1 (46.6lbs). There is always a three pound tension differential between his mains and crosses. That would range from 3-3.5lbs. Ron Yu can confirm this. This information came from Nate himself in 2009 and was discussed in previous posts.
Anytime you see Fed's main tension simply drop 3lbs for cross.
Federer has been dropping his tension for years now as have most players due to the improvements in string technology.
Federer would string lower on clay to give himself more power on the slow courts. This is where we would see a setup like 46/43.
Fast hard courts would be closer to 49/47 depending on the weather and who he is playing that day. Etc etc
It is safe to say that Federer strings mains as high as 50 (probably on hot fast outdoor hard courts) and as low as 45 (colder conditions on slow outdoor clay).
Knowing exactly what tension Federer uses is impossible. Attempting to use his tensions to replicate what he is doing is also impossible and pointless.
I was reading a FabFed thread from 2009 and people were having a huge debate about the weight differential in Fed stick compared to the retail. Arguing about lead tape in hoop or handle and internally shaving the handle to make it lighter. They never settled the debate on that thread.
In case anyone is curious, the debate is absolutely stupid! When Federer signs a contract to use a new stick (regardless if it is PJ or not) he has to order 1,000 units (Ron Yu can confirm this) in order for Wilson to come to terms. We are talking about serious business. Wilson would not just put a custom order to their factory and say "ok guys, go make idk..6 of these". It would be a bulk order under contract terms even if Fed only actually used 6 they would produce quite a lot and Fed would have paid for them all. We also know that his sticks were basically the stock version which were modded afterward. As I said before you would not change weights during matches and his frames were 9pt HL so it becomes obvious that he would be putting lead into the hoop.. and that was confirmed by the P1 photos.
The handle is the part that makes me laugh. People were talking about Fed putting lead tape into the handle. What they failed to take into account is that Fed is a P1 client and they have zero tolerance for error. Being a P1 client his handles are custom molded to fit his hand and then a custom P1 leather grip is installed (he would have been given choices of various grips). The point here is that if Fed wanted the handle to be heavier then P1 would have simply created a heavier mold for him in the first place. Their bronze package is for 30 racquets and includes custom molds. If Federer is having 500+ custom mold handles created by P1 it is absurd to think that P1 would simply need to "slip in" some lead tape AFTERWARD.
Some of you guys seem to ignore logic and blatant facts that are put in front of you. There is no lead tape in Federer's handle. IF there is more weight it would be from the custom mold. Given the specs of the racquet he would want lead @ 12 to adjust the balance, SW and RHS. This is all pretty obvious but apparently there have been huge debates over these stupid topics for nearly 10 years.