So after getting most smithing perks, accept glass, I tried to push my weapons as much as possible, without using any exploits like, dubble gear etc. Im on the xbox360.. not PC..

Dont know if this is working as intended But I drank a 50% smithing potion, and had 4 smithing Items 21% on all of them and used it to Boost my Nightingale sword, got it to 66 base damage with all one hand damage Uppgrade perks accept the last one, that you need 80 in one handed weapon to get... so the first perk is at 4/5...

I later got a stronger potion that I had created that gave me 61% but it now says I cant Improve the Nightingale sword anymore because I lack the skill ( bug or working as intended?)

I have the 40 range Nightingale with a base damage of 13, with 20,20 in the stamina and health drain... because i Read you could not improve the better version

Now Just to try some stuff out I crafted me a pair of Deadric swords, and used my 21% gear, plus 61% potion to push them up and got them to 104... Their base damge is 14, but Im guessing as I can Improve them twice as mush I get 44 more damage out of them? they can also not be improved more now as It says I lack the skill..

My question though "is this a bug" or is there an upper cap of about 200%, or will I if I use a better potion be able to push a new pair of deadric weapons even more, but then not be able to Improve them anymore??

Either way, it svcks that Deadric swords are just the best... with Dubble enchants on them and one handed damage Rings and perks you can push them to insane levels were you mostly Insta kill everything with 2 swings... kinda kill most things with the Nightingale also as it goes way above 100 damge with extra 1hand gear on... But the deadric blades can hold much more charges and do about dubble the damage.. Lame...

On a side note Using Heavy armour is usless, as there looks to be some sort of cap here also, making light armour way superior.. Using the nightingale set, but Ugly dragon armour is OFC better but I wont use it... haha no real need to be honest.. But as I can improve dragon armour twice as much I guess I could probably push it above and beyond, that of the Nightingale...

But question is... is there an Upper cap on weapon Improvment... that caps at about 200%?

Ps... illusion Is bugged... Just get Muffle spell, get magic plus and regen stuff.. and spam it about 25-30m and you have the skill to 100... Alteration works the same spam Magelight the one you shoot away, over and over and you get to the skill to 100 in no time... Spam iron daggers to get smithing to 100 also... If I had to redo my perks I probably would only get steel smithing and arcane.. as you really dont need to have weapons doing 200 damage per hit.. 100+ is enough to beat most things..

Bugs on the 360, and work arounds..

If you pick up a staff out in the woods that says it needs to be deliverd to the Elf (who sells deadric hearts) in wintherhold, have it in your hand and put it on a weapon rack/display and it fixes the problem...
If Ulfberth, co owner of the warmaidens get stuck outside his shop, on the hill, just Blow him of it with Force shout.. he flyes away and resets haha..
If you cant get the door to function when you join the stormcloaks and go on the mission for the crown... just exit and Renter the Dungeon, works everytime...
It looks like there is some grafics scaling problem with the 360 version (lol been alot of talk about it hehe) if your gear gets Low resed in view mode, drop the item on the ground and pick it up and it fixes it. Also when things start craping a fresh save fixes it.. so Delete Old save files and make new once, this is the best way of keeping the grafics degrading at bay... Iv loged about 160 hours on the game now.. and loading screan items apear low resed from time to time these days.. And some items in the world Rocks, ground etc can degrade also.. but deleating save files and making new once slows the process down... and not installing it on the harddrive I guess...
Bookshelfs and weapon Racks remains bugged, dont use them ever...

There are some funny glitches also, had me a dragon drop dead out of the sky.. just landed Dead... when I was looting a chest.. I heard a thump and turned around.. dead dragon... people can get zoomed away also, Horses are the worst as they Constantly bug out on you... I prefer not to use them anymore as I have found most locations..

But Iv managed to fix every game breaking quest bug, Even when I messed up the Guldur amulate one, I somehow got a looting spot for a dead Bandit who had the Letter on him, just at the begining of the cave.. before you jump into the hole, on that Island. and I could finish it... The only things I havent ben able to fix are the Buged Book shelfs, but hey its not the end of the world..

could u give me a shortened version of what your asking sorz i don't have a very long attention span

Calculations for working out how much you can improve armor with any smithing skill:

With the perk = ROUNDDOWN((SKILL-5)/(103/6))*3.6+2
Without the perk = ROUNDDOWN((SKILL+11/3)/(103/3))*3.6+2
For non-armor divide the answer by two.

That's from the UESP site. So at (100 + 21 * 4 + 50) armor skill, you'd get an armor boost of 50. With the 61% potion instead of the 50%, it'd be 52. Divide those by two though, since its a weapon, you get 25 and 26, which, depending on when you do the rounding (the non-armor part is sort of vague about that) might end up giving you the same improvement. Depending on your alchemy skill though, you should be able to create stronger +smithing potions, without resorting to any sort of loop exploits or even maxing out my alchemy skill, I've produce some up and around +100%.