E-sky Lama V3Posted by xilsoe Feb 07, 2008 18:47:56
Yesterday I tried the carbon inner shaft in my Lama for the first time. First I had to get it to fit inside the outer shaft so I extended the inner diameter of the outer shaft a little.
When I tried the shaft the lower insert came loose so there was absoutely no way to make it fly.
Today I will try to re-glue the insert in a way so there are better chances for the lower insert to stick. I have a feeling that the carbon might be good enough for this but experiments will show.
For the record I replaced the main motor in the walkera 4#3 Sunday.
E-sky Lama V3Posted by xilsoe Feb 02, 2008 20:30:18
I didn't have any silver brushes so I inserted carbon brushes in the Xtreme Production motors. Now it will be interesting how I like these?
E-sky Lama V3Posted by xilsoe Feb 02, 2008 15:42:36
Today I completed the carbon fiber inner shaft for my Esky Lama V3. I cut the carbon pipe and glued the steel shaft ends into the carbon pipe using 15 minutes epoxy. I have left the glued shaft to dry for 24 hours as this is how long the epoxy needs for full strength. So maybe tomorrow I can try if a carbon fiber inner shaft can be used
I have also found out that I will have to shorten the screws that holds the lower rotor hup in place. Otherwise they will go into the carbon and stop the upper rotor from rotating. I'll have to do that when I mount the shaft. Right now I am feeling confident this can work but it won't be proven before I try.
I have also put both shafts on my scale. The steel shaft is about 3g and my homemade carbon shaft was 0g
I have aquired an ESC and some silver paint for my old Tamiya Vanquish. I decided to go with a 12T ESC. It will be interesting to get this old car painted and running again
E-sky Lama V3Posted by xilsoe Jan 30, 2008 20:33:26
Today I received the carbon fiber pipe I am going to try for main shaft. The outer diameter is 3mm and inner diameter is 2mm. This will go inside the outer shaft. I also cut up an old inner shaft to make the shaft ends and tried how they would fit insde the carbon pipe. The fit is perfect
The perfect fit hopefully means I will be able to make a good inner shaft.
In the mean time I am considering getting my old Tamiya Vanquish running. I have decided I want to add a new speed controller. I would like to get an ESC that will allow me to use a LiPo. The motor in the Vanquish is similar to a Tamiya Techni Gold and I have found out I will need an ESC that can handle a 17T motor.
Hopefully the new ESC will also permit me to get rid of the receiver battery pack. There never was room for that in the car anyway.
At the same time I would like to complete painting the body. I couldn't get the aluminum color when I build and painted the car back in 1988 or whenever I got the car.
I think I may need to do something to get the Transmitter working again as the battery holder is probably broken.
It seems that these old Tamiya cars are becomming collecters items I just saw a Vanquish had a bid on about 60$ and I have heard up to 300$. I am going to keep mine though for now though.
It will be interesting to get that old car running once again
E-sky Lama V3Posted by xilsoe Jan 27, 2008 16:03:32
The idea with using the 2,5mm tail pipe from my walkera 4#3 didn't work because the shaft ends I had proposed couldn't be made so now I am going to try using a 3mm carbon pipe with an inner diameter of 2mm. The standard shaft should fit precisely inside this so there is no need to modify the shaft. I will just have to jut the shaft. It will be interesting how this will work out
If the carbon doesn't work I will go for titanium.
I have also done some other weight reductions that were suggested to me: I have put rubber bands in place of the battery tray and I have cut the windows in the canopy open. The overall weight is now about 236g. It feels as the Lama has become tail heavy so i might move the 4in1 a little forward.
After the weight reductions it seems like I am flying forever
This make me want to do even more weight reduction. The flybar is an obvious place to look for reductions.
E-sky Lama V3Posted by xilsoe Jan 20, 2008 19:15:29
I believe I have figured out how to make the carbon inner shaft:
I will use the old tail pipe from my walkera 4#3 for the shaft. It is 2,5mm but will go inside the outer shaft. Ihe inner diameter is more than 1mm but less than 1,5mm.
At the ends I will make steel ends from an inner shaft. Some part of these steel ends need to go inside the carbon pipe and these must be glued together.
I did some research on glue and I found out that epoxy woud be the appropriate glue for putting the steel and the carbon together.
The last remaining problem is how to reduce the diameter of some part of the steel ends so they will go inside the carbon pipe?
And then to actually do this
E-sky Lama V3Posted by xilsoe Jan 19, 2008 14:03:32
Today I received my new charger. It is a Bantam E-station BC6. I picked this because of the integrated power supply and because it will take 6LiPo cells also I didn't find any bad reviews on the net. I believe I might want to charge 6 cell packs at some time if I get a big T-Rex. Anyway I like it a lot
I decided I needed a new charger when I measured one of my batteries and found the voltage of one of the cells to be 4.21v. After that I didn't trust the E-sky charger.
Regarding weight reduction I got the idea that the main inner steel shaft could quite easily be replaced by a carbon fiber shaft. The same actually goes for the flybar, so I started a thread on RCGroups asking about this: http://www.rcgroups.com/forums/showthread.php?t=803991
nobody has responded yet. I am a bit concerned if the carbon will endure the torsion and how the screws in the gear and the rotor head will affect the carbon.
If nobody responds I will just have to go ahead and try
The main shaft is 2mm and the flybar is 1,5mm.
The weight of the stock main shaft is 4g. I believe I could save 2-3g by replacing this.
E-sky Lama V3Posted by xilsoe Jan 12, 2008 16:32:24
Today I received some spare parts for my walkera 4#3 so hopefully this bird will soon be flying again, but not yet as I haven't repaired it yet
Along with the spare parts I had also ordered a set of new servos for my Lama. This was mainly to save some weight as all this bling I have fitted has made it heavier. The servos are the Tower Pro SG50 and they fit almost perfect in the frame. I had to remove the mounting pads from the servos as these didn't fit into the Lama frame. Otherwise it was a perfect fit
I had expected the servos to be about 5 grams but they seemed heavier so I decided to shorten the wires to make them lighter. The most easy way I found was to remove the buttom cover from the servo and unsolder the wires. Then I shortened the wire, re-soldered the shortened wire and put the buttom cover back on. This reduced the weight to about 5g each
The plugs didn't have to be changed at all. The servos plugged right into the 4in1 and worked perfect.
I had to trim the Lama a little bit as I had changed the servos. After quick trim the Lama flew perfect again.
When I flew the Lama I had a feeling it had become more agile. Perhaps this is the combined effect of better servos and a lighter Lama. It also seemed to me that the motors were doing less RPM and I had more flight time
I am very happy with this upgrade
When (if) I upgrade the Lama with brushless motors I should be approaching the ultimate Lama.