Liftoff (FW) build diary

I've finally got most of the parts I need for the build so I thought I'll follow most of you and keep you updated on this build diary - at the same time any advice and comments are more than welcome as I'm no expert in this field!

So some details first - Liftoff shall be a LP flipper track driven by two motors. Details Below:

Drive type: Tracks
Motors: X2 Makita 6347D
Esc: Sabertooth 2x60
Armor: HDPE (plus steel if weight permits :roll: )
Weapon: LP flipper Co2 63mm bore cylinder

Pneumatic system parts mostly available and assembled, remaining is the cylinder which will be machined locally.
Will post some photos soonish.. :wink:

This is the pneumatic system, still missing the cylinder... Used 1/2'' fittings through out. Not yet fully tested as I got no Co2 available yet :cry: But monday I'll get an expired fire extinguisher and I'll have a go at refilling the bottles (I'm slightly concerned as this is my first fill! :roll: )

Partially tested the system at 6 bar this week and it worked fine, removed the regulator and supply tank and connected an airline to the 5 way valve inlet, energized the solenoid and bang - QEV opened and there was a large flow of air from the T-piece just behind the QEV.

The pressure gauge on the buffer tank is just a temporary thing - to compare the pressure to the regulator when I go to 11bar with Co2


http://i8.photobucket.com/albums/a49...z/P1060538.jpg

Another view, it will be quite a squeeze - 1/2 fittings don't come small nor light!

http://i8.photobucket.com/albums/a49...z/P1060539.jpg

All connected and ready to go - but just not yet, that extinguisher is still serviceable so I just checked every thing bolts on, Monday will borrow another one :D

http://i8.photobucket.com/albums/a49...z/P1060540.jpg

Where did you get the fitting to go from the co2 but to the ball valve?
Are those standard hydraulic ball valves?

off ebay, its a complete fill station for Co2 bottles, came complete with digital scales.

Ball valves look quite thick-walled heavy duty type, surely not normal compressed air or water type

Got it form here:

http://www.ebay.co.uk/itm/New-Deluxe-Du ... 668wt_1076

Got a question regarding HDPE, I'm using a 5mm thick HDPE baseplate for the build, but the material I got is warped and now I'm not sure if I want to use it any more. Is it normal for HDPE to be like that as even a couple of solid rods (30mm and 40mm dia) were bent?

I'm tempted to replace HDPE with an aluminium base plate but that will double the weight :cry:

5mmhdpe wont be that good base plate if your mounting stuff to it, it will bend quite a bit.

3mm ali is agood option, slightly heavier and a lot stronger, Battle axe only did a little dent to laser's base.

Hmmm :? thought Hdpe was quite stiff, similar to nylon.... that is, until I got the material this week :shock: , its quite bendy!

Will see if I can leave the 5mm hdpe base and reinforce it with alu - if not possible will have to opt for an all aluminium base plate.

The robot design should be quite sturdy, but in the end I will only know when its all assembled!

Depending on how you're building it the HDPE might be ok. If you're mounting stuff to it and trying to make it the part which holds the machine together than you've had it, but if you're using it as a baseplate and having bulkheads attached to it and other bulkheads thats where your strength can come in and it'll be fine. The latter is the way Cicatrix is built and it's pretty tough with a 6mm HDPE baseplate.

this is a basic idea of the robot layout, the back end will be quite rigid as there's a 70x70x5mm alu box section which will house the motors, that will be bolted to the base plate, the sides will be 10mm hdpe bulkheads containing the tracked drive. The front is my concern as there's nothing connecting the track housings to each other... I'm not sure about this but I believe that with the flipper arm retracted the whole thing should be pretty rigid, but flipper up I don't know!

http://i8.photobucket.com/albums/a49...uild/robot.jpg

This is the progress done so far. Its difficult to introduce a fwd bulkhead because the pneumatics are in the way!

http://i8.photobucket.com/albums/a49...d/P1060557.jpg