MPA
Elite Veteran
Location: Australia
| Hi
Well the legs look a bit more substantial, still a bit tall.
Those lengths of flat from one skid to the other side.
Id suggest you only need some thinner strap or cable across them to ensure they dont spread.
Perhaps the reason they are so large is to support the frame structurally a bit but thats not going to work out that way due to the direction of loadings on it.
Keep in mind that the higher the thing is the more force that is applied to those joints and legs.
Simply the amount of leverage on the joints is increased the longer they are.
You can do this two ways, shove bits together and hope or do some basic maths on the parts you are using to calculate load capacity.
Then youll know if things will break or not.
The leg joints for example
Work out the load on them by measuring the length of the leg to determine how much torque is on the joints.
Calculate the modulus of the alloy pipe to determine what load it will yeild (bend) at.
If thats all a bit much and you want to do it by trial and error then youll have to lean more to the solid side than the flimsy side of construction.
If you build it tougher than it need be it might be too heavy but at least it wont break up.
Once youve got the basic rig then you can trim it down a bit but dont go making it under rated for the stress it will have on it.
Adding to the height as you have it assures everything on it will have a lot more load than a smaller rig and so you would have to have proportionatly larger components to ensure it doesnt break, as you can see for yourself if you compare to other rigs yours does not have heavier duty fittings and so with all the extra lengths it is more than likely some part of it will come adrift not to mention unruly in flight.
The "signs" on the side are best on a sandwich boards on the ground where your working, they are sails on the heli and any wind will see the tail wagging the dog.
(Mount takes over flight from Heli)
To be honest there is a list as long as my arm of things you need to modify or rectify on it.
Im not sure if all of those things will be interperated by you to your benefit.
My advice at this point, if you are not going to simply copy another design that others use and want to recreate your own style of mount then youll have to do a good deal more homework before you even get out the hack saw, and spend a lot more than 3hrs on it let alone 3 weeks.
If you are trying to cut costs down, you can do that to a limit but after that youll be putting a lot more worth of heli at risk than youll save on the mount if it breaks up.
Blazek, I'm not going to blow smoke up your arse and tell you its all good..
Not everyone is cut out to construct or make their own mount.
I am a qualified motor mechanic and have done some additional part time schooling for things like metal fabrication and welding so I dont find it too hard, I just lack things like machinery to cut and mill things as neatly and easy as Id like.
When I look at a commercial mount, to me it looks like a hundred bucks of alloy, cf and bolts.
To some others it looks like an intricate technical item.
To some others it may as well be a tree stump, so long as it fits on the heli and carries a camera.
As youve only spent a relatively short time making the thing Id suggest at this point you cut your losses and get yourself an Airfoil mount.
Your down about $30 of alloy so far.
My view is by the time you have something your going to get working well you are likely to be worse off financially than if you'd purchased one..
Ive said it before to others, the Airfoill is cheap and does the job.
For some folks out there they will spend a lot more hacking up chunks of materials to make one and a lot more hrs wrestling with it.
Order off the net, open the pack, push A into B and B into C, strap it on the heli, shoot pics and be happy.
Heliscan mount is another underslung mount, we havent had anyone here with mileage on one just yet and it may turn out great, for now you dont need to be sorting bugs on new design rigs you need a proven one you can just fit and use and and the Airfoil is that.
Failing that Id be taking a good hard look at others mounts and if in doubt just copy the construction to the letter, at least you can be sure its working for them and so should follow for you.
I do this myself.
I have just completed another remote vision project myself and I have copied quite a few things and copied from the top of the range gear worth 20 thousand +.
I made mine for under 2 thou AU.
Some might think I just made the bits all neat, put it together and crossed my fingers
But there was weeks of calculations and lots of drawings and dimension changes before I got the saw out and purchased materials.
Ive been at it since December last year.
All the extra time paid off because it works exactly as planned.
In fact even better.
But the fact is it is something that I do not have the pleasure of making errors with due to the dangers, the same follows with the heli and the mount just on a smaller scale.
These mounts may look like they are just a strung together by trial and error but youll find a good deal more time is spent on them before a single thing is cut to size.
There is no shortcut way around that other than laying down cash for one from someone who has the ability to make a good clean end product that will handle the load more than adequately and not upset the heli in flight.
Regards
Dave |
