Register

If this is your first visit, please click the Sign Up now button to begin the process of creating your account so you can begin posting on our forums! The Sign Up process will only take up about a minute of two of your time.

Page 4 of 25 FirstFirst ... 2345614 ... LastLast
Results 76 to 100 of 615

  1. #76
    Edgar Perez's Avatar
    Join Date
    Dec 2001
    Location
    Gurabo, PUERTO RICO (USA)
    Posts
    1,941
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Got my UMS one coming too
    Edgar Perez
    Puerto Rico

  2. #77

    Join Date
    Dec 2004
    Location
    PlaistowWest Sussex, UNITED KINGDOM
    Posts
    407
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    I received my UMS a few weeks ago but I have been busy with work and finishing off a Viperjet. When I get around to it I plan to get it all working on a bench before I install it. Shane, have you started yours yet?


    John
    CRASHING IS NOT AN OPTION.

  3. #78
    JohnMac's Avatar
    Join Date
    Oct 2002
    Location
    Leeds, UNITED KINGDOM
    Posts
    1,288
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Very interesting post this. I am just about to order a JL Mig 29 from Jeff Sewell, their UK agent. I have to decide on the colour scheme. The last thing I want is a jet with UC problems so I would be very interested to hear about actual results from people who have fitted the UMS system. What is the cost of the system please?
    Thanks

    John

  4. #79

    Join Date
    Dec 2004
    Location
    PlaistowWest Sussex, UNITED KINGDOM
    Posts
    407
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    John,
    The kit has cost about Β£110.oo delivered. I don't know, at this stage, whether it will require different internal cylinder pistons making as the original ones have rubber O rings as seals.( This may be an issue?)



    John
    CRASHING IS NOT AN OPTION.

  5. #80

    Join Date
    Jan 2004
    Location
    Irvine, CA
    Posts
    1,550
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Hi All,

    Before you all jump into the hydraulic system, we should look into the new modifications and improvement that JL is making. I was informed that the new gear improvement would be done in 2-3 weeks and will be made available for our MIG customers. We will test them and ensure that they are functional.

    Will keep you all posted.

    Thanks,

    Mike
    Global Jet ARF PRO- Air-C-Race-Germany, CNC-Italy, Feibao, Gryphon/Redwings, Der Jet, Jet Legend, Ripmax Xcalibur, Aurora & more - globaljetclub.com

  6. #81
    F15driver's Avatar
    Join Date
    Dec 2001
    Location
    New Braunfels, TX
    Posts
    250
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Mike,

    Don't want to make this a ***** session but when and how were you informed of the gear modification? My Mig 29 is on its way here and I knew nothing of the modification even though mine has been on order since about the end of June. It seems one of JL's main problems is real lack of communication on things such as this.

    I'd be interested in your response.

    Regards,
    Rob
    F15driver
    Don't look back, they may be gaining on you!

  7. #82

    Join Date
    Jan 2004
    Location
    Irvine, CA
    Posts
    1,550
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Hi Rob,

    Did you order it from us? If so, normally we should keep you well informed because our factory is in China and our engineers are in constant communication with them without problems. Yes, the communication could be an issue oversea for them. The modification is in progress, and we will get a set and validated before we release them to our customers. I am not sure about your order because we don't have ways to track your order and version number on your L/G. We will post our evaluation results over here.

    Mike
    Global Jet ARF PRO- Air-C-Race-Germany, CNC-Italy, Feibao, Gryphon/Redwings, Der Jet, Jet Legend, Ripmax Xcalibur, Aurora & more - globaljetclub.com

  8. #83
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Ok Guys

    Sorry I have been out of the loop, but work has kept me busy.

    I can quite happily say that I finished the upgrade tonight and I am extremely happy with my results.

    Mike I know you have been working with the factory, but I am sad to say I doubt that the mods will hold up after time. The first thing I notoced when I dis-assembled my cylinders ready for the mod, was that the hard drawn stainless steel I had used to upgrade the alluminium shuttles had also started to groove out, this was only after about 6 flights.

    The therory of how the shuttles and locking balls work is absolutely wonderfull, however in practice the shuttle balls are being forced into the cylinder wall every time you retract. This translates into the weakest material failing.

    By upgrading the shuttles, I had increased their hardness (about 55 Rockwell) but the balls are still harder and they are being jammed in between the shuttle and the cylinder wall. The SS shuttles show significant wear and there are now minor tracks (grooves) evident in the cylinder wall, left alone the end result would be stuffed cylinder barrels and ever increasing failing of the UC to cycle......

    I must also say, that as one of the first customers for the JL Mig (I think the first to fly outside of the factory) and being the one who "Quietly" explained to Yang (JL) what the problems were and what I had done to try and resolve them, I have not once heard back from the factory with any follow up info or an offer to upgrade to the "fixed" version, that is very poor customer service!!!

    Anyway, I will start posting the build photo's of what I have done as promised so you guys can make a decission which way you want to go, for me it's an easy decission as in all my flights of me JL Mig, I have onle ever seen it ONCE with ALL the gear up......
    Bart

  9. #84
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Okay

    First part of the mod was to strip the cylinders from the plane. This can be quite easy if you remove the "e" clip from the pin that connects the cylinder rod onto the leg, be carefull when you pull the pin out as there are some small brass shims and spacers in there so put a rag or paper underneath to catch it all. Once you disconnect the rod, grasp hold of the barrel and turn it anti clockwise (looking at the rod end) and undo the barrel from the cylinder end that is in the fuse. The barrel is sealed to its end with an O ring and should not be tight, so there is no need to get to heavy fisted.

    Once you have undone the barrel, you will be left with barrel, rod end cap, piston and rod assembly. Place the rod end cap (the other end that screws on the barrel) in between some alloy jaws on a vice 9with a rag to stop scrating the powder coat0 and close the vice BUT not all the way, you just need to gently hold the cap. The casting that holds the pressure nipple will become an anti-rotation device so simply grasp the barrel again and undo it fron the rod end cap, once done simply withdraw the cylinder rod and piston from the barrel.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	yw66430.jpg 
Views:	15 
Size:	141.1 KB 
ID:	1520375  
    Bart

  10. #85
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Once the rods and pistons are removed, gently remove the o rings from the piston and place the piston in the vice soft jaws, do the vice up but not too firmly. Place an allen key or such through the rod eye and try undoing the rod from the piston. If the piston spins in the jaws do it up a bit more, if the rod end starts to unscrew from the rod, then do it back up again and heat the piston end of the rod with a heat gun to entice it to undo. Never grip the rod with pliers or alike as it will damage the chrome and you will forever have leaks. If the rod still resists then grip the rod with vice gips and alluminium strips to protect the rod.

    I have operated on mine a few times now, and I doubt is anyone will have troble, even with thread licker applied.

    Once the piston is off, put the rod and cap aside in a safe place.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	jh16757.jpg 
Views:	23 
Size:	139.0 KB 
ID:	1520380   Click image for larger version. 

Name:	wr53670.jpg 
Views:	18 
Size:	156.7 KB 
ID:	1520381  
    Bart

  11. #86
    Jeremy_D's Avatar
    Join Date
    Feb 2005
    Location
    Central Coast, AUSTRALIA
    Posts
    1,000
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Hi Shane,

    First I have heard of the upgrade as well. I remeber the email you sent through with the drawings. I have sent an email to Yang and will give you a buzz when I hear back from him. I gave him a friendly reminder about the drawings you sent through Talk to you soon

    Cheers

    Jeremy
    Global Jet Club Australia
    www.aussiejet.com
    http://www.facebook.com/aussiejets

  12. #87
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    At this point, you now have the offending piston which needs to be modified or replaced. For those with the means, just manufacture new pistons and assemble. For those without the means, I have used a method that re-uses the piston but without the troublesome guts.

    In EACH end of the piston, you will find a small countersunk socket head (allen key) screw, these screws hold a conical shaped washer onto the shuttle spool that traps the ball bearings and holds them in, on the main gear there is only one set of bearings, on the nose leg there are 2 sets.

    On the mains shuttles, place an allen key in both ends and start to undo them, it is very important that the screw in the open end of the piston undose first, you can view this through one of the holes in the piston side. If the other end (through the hole where the rod screwed in) starts undoing first, screw it back up tight and stick a hot soldering iron on the screw in the open end of the piston to heat it up, this should make it easier to undo first.

    EWhen the screw is out, drop out the washer and remove the 3 ball bearings, once bearinfgs are out then push the shuttle out.

    With the nose gear piston, follow the same procedure as above, except when the 3 ball are out, put the screw & washer back in with some good thread locker and give it an hour to go off (use cyno if you are pressed for time and brave), once the locker has cured undo the screw in the rod end of the piston and pull the shuttle out, remove the extra 3 balls and push the washer and screw out.

    You can see the grooves in the stainless steel ring caused by the balls.....it was never going to work by the looks of it
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	nl29267.jpg 
Views:	22 
Size:	154.0 KB 
ID:	1520382   Click image for larger version. 

Name:	cx77031.jpg 
Views:	13 
Size:	154.2 KB 
ID:	1520383  
    Bart

  13. #88
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum


    ORIGINAL: Jeremy_D

    Hi Shane,

    First I have heard of the upgrade as well. I remeber the email you sent through with the drawings. I have sent an email to Yang and will give you a buzz when I hear back from him. I gave him a friendly reminder about the drawings you sent through Talk to you soon

    Cheers

    Jeremy
    Good to hear from you, hope you got all that marriage stuff out of the way now and can get back to some flying,,,, sparksy looked awefull lost up at Temora
    Bart

  14. #89
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    With the piston guts removed, I machined up some alluminium plugs and Hysoled them into the pistons. It is very important to fill the voids fully as any cavity left in there will cause oil to by-pass, I had to do one of mine a second time cause I rushed it. It is ideal to actually semi fill the holes with the hysol to ensure no leakage.

    Once the hysol cured, screw the pistons back onto the rods with a bit of thread locker, re-fit the seals, slide back into the barrels, screw back onto the barrel cap in the fuse and connect the rod end back onto the leg. The liberal use of vaseline along with a nerve calming medicinal brown ale can assist with getting the shims and spacers back in place. The "e" clips that vanish are commercially available from bearing or bolt stores.

    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	lj22931.jpg 
Views:	14 
Size:	164.0 KB 
ID:	1520386   Click image for larger version. 

Name:	xs59082.jpg 
Views:	14 
Size:	156.4 KB 
ID:	1520387   Click image for larger version. 

Name:	ch95232.jpg 
Views:	14 
Size:	151.8 KB 
ID:	1520388   Click image for larger version. 

Name:	lf94130.jpg 
Views:	15 
Size:	153.1 KB 
ID:	1520389   Click image for larger version. 

Name:	tf49110.jpg 
Views:	12 
Size:	165.8 KB 
ID:	1520390  

    Bart

  15. #90
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Now we have done the tedious mod part, we can get into the more exciting part and assemble those shiny new bits.

    As I mentioned earlier, the Hydraulic system consists of 4 main components, Hydraulic gear pump, Oil reservoir, 2 position 5 way directional valve and the electronic pump controller. I use the UMS brand which come out of India (already fitted to a 3 of my jets) and I think can be sourced from Speedfreaks here in the land of Aus.

    The first step is to mount the components and in this case I put the pump & reservoir in the engine bay well away from the hot bits and just behind the CG. I wanted to move my CG back a little and in this spot I could easially compensate by placing the pump battery forward a little.

    I found that a simple plate with the pump on one side and the reservor on the other was a neat solution and more importantly kept the suction line nice and short. The reservoirs are fitted with a clunk line from the factory that allows great flexibilty for location.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	tq48926.jpg 
Views:	22 
Size:	158.9 KB 
ID:	1520392   Click image for larger version. 

Name:	kf12215.jpg 
Views:	15 
Size:	149.4 KB 
ID:	1520393   Click image for larger version. 

Name:	ej14450.jpg 
Views:	12 
Size:	169.7 KB 
ID:	1520394   Click image for larger version. 

Name:	ha78541.jpg 
Views:	11 
Size:	152.3 KB 
ID:	1520395   Click image for larger version. 

Name:	sd44739.jpg 
Views:	16 
Size:	163.5 KB 
ID:	1520396  

    Click image for larger version. 

Name:	gx30377.jpg 
Views:	14 
Size:	138.7 KB 
ID:	1520397  
    Bart

  16. #91
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    The next assembly part is the directional valve. These valves are operated by a servo of your choice, it does not need to be too strong but I guess selected for its benifits. In my case I used a simple (low grade) thin wing servo as it allowed me to place the assembly below the front cover of the turbine again allowing me to keep everything close.

    From experience, I know that using ply mounting plates, there ends up being alot of flex, so I now only use a carbon fibre plate to keep everything stiff.

    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	qo41212.jpg 
Views:	14 
Size:	176.8 KB 
ID:	1520398  
    Bart

  17. #92
    Jeremy_D's Avatar
    Join Date
    Feb 2005
    Location
    Central Coast, AUSTRALIA
    Posts
    1,000
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    [/quote]

    Good to hear from you, hope you got all that marriage stuff out of the way now and can get back to some flying,,,, sparksy looked awefull lost up at Temora
    [/quote]

    Lol - smeone just needs to give the poor man a beer and he'll find is way.....Building a new sport jet after a rather slow landing approach with the reaction and a cross wind...not a good combo!! Should be up and flying again pretty soon
    Global Jet Club Australia
    www.aussiejet.com
    http://www.facebook.com/aussiejets

  18. #93
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    The valve assembly is now placed in position and all the lines connected.

    The connections onto the valve, as it has barbed fittings need to be lock wired, in addition all the connections onto the cylinder barbs need to be lock wired as well. This adds a high level of security and integrity to the connections.

    From the reservoir to the pump is 4mm air line, from the pump to the directional valve is also 4mm airline, this pressure line MUST be fitted with a one way (check valve) normally included from UMS, if you don't have one then get hold a "Festo" type check valve, but here is the tricky bit, some of the check valves automatically are pushed open when you insert the 4mm line, these are useless for the application...make sure that when you push a piece of airline into the check valve that it only allows air to flow in one direction.
    It is this check valve that holds the oil in the cylinders and keeps them down or up (indefinitely).

    On the directional valve on each side of the pressure line are another 2 nipples that are the oil return lines back to the reservoir, these need to be tee'd together and run back to the reservoir in 4mm tube. On the other side of the directional valve is the A & B ports that connect to the cylinders. I come off these in 4mm line and then reduce each one down to 3mm for the run into the cylinders. The original lines fitted from the factory are fine to use, but the tee pieces that "push into to 3mm tube" need to be replaced with Festo type that go over the tube to keep the pressure losses to a minimum.

    The final placement of the controller and battery will be determined by the CG which I will check tomorrow.

    I will get some video on the weekend of it operating and post it. I have now cycled the gear 30 plus times and each time it has been perfect (still on the same battery).
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	jh17166.jpg 
Views:	16 
Size:	171.7 KB 
ID:	1520411   Click image for larger version. 

Name:	vt56295.jpg 
Views:	14 
Size:	132.3 KB 
ID:	1520412  
    Bart

  19. #94
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    ORIGINAL: Jeremy_D
    Good to hear from you, hope you got all that marriage stuff out of the way now and can get back to some flying,,,, sparksy looked awefull lost up at Temora
    [/quote]

    Lol - smeone just needs to give the poor man a beer and he'll find is way.....Building a new sport jet after a rather slow landing approach with the reaction and a cross wind...not a good combo!! Should be up and flying again pretty soon

    [/quote]

    Bummer about the reaction..I have started building my FEJ A10 and should be ready in a couple of weeks if I get a break from work..
    Bart

  20. #95
    ianober's Avatar
    Join Date
    Aug 2002
    Location
    San Mateo, CA
    Posts
    4,414
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Great stuff Bart. I started doing my mod last night as well. I have been breaking down the gear and pulling out the piston shuttles. I too thought how I was going to keep oil from passing through the piston and the shuttle shooting out. I decided to machine up new pistons on my mini lathe, shouldn't take too long. I just need to figure out the thread on the end of the shafts so I can tap them.

    Mike, dont forget that whatever JL does for a mod will need to be done on the SU's out there too, the gear is essentially the same.

    Bart, how do you go about bleeding the air out of the system when you are filling it with oil?

  21. #96

    Join Date
    Dec 2004
    Location
    PlaistowWest Sussex, UNITED KINGDOM
    Posts
    407
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Great stuff Shane. Are you using the original rubber O rings on the outside of the piston?




    John
    CRASHING IS NOT AN OPTION.

  22. #97
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum


    ORIGINAL: ianober

    Great stuff Bart. I started doing my mod last night as well. I have been breaking down the gear and pulling out the piston shuttles. I too thought how I was going to keep oil from passing through the piston and the shuttle shooting out. I decided to machine up new pistons on my mini lathe, shouldn't take too long. I just need to figure out the thread on the end of the shafts so I can tap them.

    Mike, dont forget that whatever JL does for a mod will need to be done on the SU's out there too, the gear is essentially the same.

    Bart, how do you go about bleeding the air out of the system when you are filling it with oil?
    The cylinders are so big that they self bleed after about 3 cycles, just pre-fill the reservoir before you do the final hook up. It is important tp get all the air out and I got the last of it out by standing the plane on its end and cycling the gear a couple of more times. You also need to be able to top up the reservoir after the commissioning.

    This I do while the plane is standing on its end (So that my tank fittings are at the top) and remove the suction line from the pump and connect a squeeze bottle full of oil to it and remove the return line from the reservoir, give the bottle a squeeze and watch the oil level in the reservoir and fill to about 80%. Might seem a bit fidly but you only ever need to do it once unless you get a leak.

    One important thing to note, when you first start the system, the pump will be dry which is fine as the pump will self prime quite happily under normal conditions, however the check valve on the pressure line will stop this happening until the pump actually gets oil in it. So you need to make sure to pre-fill the suction line right to the pump if you can or remove the check valve for the first few cycles. Once the pump is primed just drop the check valve back in the line. This you only need to do if you dis-connect the suction line and let the air in.
    Bart

  23. #98
    Aussie Bart's Avatar
    Join Date
    May 2006
    Location
    Sale, AUSTRALIA
    Posts
    363
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    The standard O rings are Buna N material which we use in our industry (Hydraulic) all the time providing you stick to a mineral oil. All of my experiance with hydraulic retract mods has taught me that the very best oil to use is sewing machine oil, quite easy to get in larger containers (1 lt).

    This oil is light enough to get through the system and is mineral based so does not attack the seals. If for whatever reason you find the the oil you use does swell the seals because its not mineral based, then just chase up with your bearing or seal supplier for some "Viton" seals.

    However try and get the sewing machine oil as I believe it is the only oil that will work properly in the application.
    Bart

  24. #99
    ianober's Avatar
    Join Date
    Aug 2002
    Location
    San Mateo, CA
    Posts
    4,414
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Great stuff Bart, cant wait to get my parts!!!!! Gonna go home and finish machining my new pistons.

  25. #100
    Alex48's Avatar
    Join Date
    Aug 2006
    Location
    , UNITED KINGDOM
    Posts
    1,466
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Jetlegend Mig 29 Fulcrum

    Very interesting mod Bart, thanks for posting. I've just ordered a load of stuff from UMS to have a play with and your thread will be a great reference. I presume all the gear doors are still air?

    Cheers, Alex


Page 4 of 25 FirstFirst ... 2345614 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
All times are GMT -6. The time now is 02:59 PM.

SEO by vBSEO 3.6.1 ©2011, Crawlability, Inc.