Sewdhull
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Posts posted by Sewdhull
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There are batteries of lower capacity that can provide more current and the opposite is true.
I have a few 5 to 10C batteries I used for RC stuff but these have a capacity of a few Ah so still provide a reasonable current, well enough for the servos and avionics etc.
The C rating is a way you could compare batteries of differing capacities, but what is changing is thier IR. It's an industry engineering thing which i now used in marketing with all the reliability that brings. Get a decent charger and compare the IR yourself, its a comparison more than a measurement because it will vary.
Manufacturers use thinner separators ,varying formulations of electrolite to get different characteristics.
For example, nanotech cells seem to be similarly formulated both large and small and do tend to have lower IR when they are larger. The lithium ion 18650 cells have rated currents and capacities which vary wildly given the cell is a fixed size.
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13 hours ago, Mad dog 49 said:
What are the collectives thoughts on carbon steel inner barrels?
Corrosion,
Stainless or brass, Stainless if there's got to be a winner
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Yes it has IR function. Chargers haven't got better in a long time, so there's lots of good ones out there. Cabling is often an issue but if all your batteries have the same plug it won't matter. XT60 for the win.
If you test the battery when new, fully charged, then test occasionally will see the battery decline over time.
Useful for comparing know good batteries to any new ones you get.
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A good charger will do that the IMAX b6 type and it's clones for example. They aren't expensive about 35 quid.
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Other than the plug and it fitting, there's no Airsoft battery as such.
You can imagine that batteries, even small ones that supply more than a hundred amps regularly need to be 'better' than a battery putting out 40.
I use Amazon batteries and some nano techs and whilst youd notice it on a drone in a gun you don't.
I'll charge all mine up, leave them a day and see what the rof is and put a new post up. Maybe I'll have my super dooper lion battery made by then.
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The volumes of the cells do vary at similar capacities, more volume can give you more capacity and/or more current ability.
Worth bearing in mind that drawing more current will reduce the capacity of the cell.
By which I mean less current will give you more mAh.
In Airsoft you don't usually need high C, low internal resistance batteries.
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Nuprol use the same cells in thier batteries as everyone else. The only batteries I've found that seem to be better are the turnigy nanotech ones, unless you count the great drone ones.
Too low an internal resistance, read high C, doesn't happen on a battery, only the voltage.
Use a MOSFET to save the contacts and if a MOSFET let's out it's smoke, it's still not the battery.
The only way a battery can do bad things is if it's connected the wrong way round.
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For pretty much all Brushless motors don't use active braking or rate of fire reduction, including smart trigger. Some motors might work with these but its a bad idea anyway.
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What features were you after, I used a simple mosfet switch for my dmr. Pull the trigger it shoots once. Now I have the folo
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The low capacity just means you'll need more of them, the nanotech batteries are pretty good I have found.
Is that the largest battery you can fit? You can refine the search for hobby king batteries using dimensions... you may already be aware.
https://hobbyking.com/en_us/turnigy-nano-tech-1200mah-3s-15-25c-lipo-airsoft-pack-t-connector.html
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If this is happening after the gun has been working fine then it's cut off lever wear most likely, maybe trigger trolley. The contacts don't have a way to close up over time, only open wider.
If it were me, I'd get a new cut off lever and set of contacts ( they cheap). With the gearbox together still you can see the operation of the lever and trigger trolley and see how the cut off lever behaves, but it is this lever tipping the trigger trolley that gives you semi when the sector gear flips the trolley up.
If the contacts look good, just replace the trolley and leave the contacts alone.
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It's the fit really and yes some clips fit better than others at least that's been my experience. I have used a little epoxy to pad out the clip so it has no play, but you need to carefully align stuff and then let it cure. In short, I roughed up the barrel flats, degreased em, then put a little epoxy on the flats and put the clip on. Once the epoxy firms up take the clip of and use a knife to tidy the excess. In a perfect world id put the epoxy on the clip but it doesn't adhere as well to the clip as the barrel.
If the barrel and bucking are moving together you can shim the bucking to the hop with PTFE tape. Also make the front part of the hop snugger onto the barrel (where the ring goes in if you have one)
If the barrel is moving inside the bucking you can shim the front part of the bucking to the barrel and make the front part of the hop snugger as above.
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This thread was resurrected a few days ago, but in General help
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1 hour ago, Pseudotectonic said:
500C heatgun didn't seem to remove the springiness on the compressed coils on my m90
Not even if I tried to get it to settle afterwards by compressing it for a week inside a torch
It was nowhere near cherry colour tho, it did darken the bright shiny metal a little (could just be surface grease)
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I guess the 20 FPS loss from removing the bearing is actually because the rotational friction on the non-bearing side is slowing its decompression
Try playing with a spring by hand, but twist it or keep it from spinning, the twisting itself is going to affect it wants to expand/compress, in fact you can try to compress/decompress the spring by the twisting alone
You need 800+Celcius to anneal springs, stainless is higher.
The 20FPS loss is because the spring is less pre compressed, there's no extra friction in having 1 bearing instead of 2. I'm going to explain why because it's come up before.
If you compress a spring one end will rotate with respect to the other and if you have a bearing at one end, that end will rotate freely because bearings have less friction than the spring rubbing against another flat surface and once the bearing is rotating there is not enough force to rotate at the other end. The whole spring is not rotating, the wire is repositioning itself as it is put in torsion, so if it is fixed at one end the other rotates.
In Airsoft we have bearings not for friction issues, but so that the spring maintains its shape and does not bend to one side or the other when it gets compressed. You could fix the spring at both ends and have no frictional losses but you would still have the spring deforming as it compresses.
If you put a bearing at both ends and lets say, one bearing is a bit stiffer than the other, then the bearing with the least friction will rotate first, but the other bearing will not rotate because the force to rotate it never gets high enough since it is relieved by the first bearing to rotate. This is essentially what happens if you have just one bearing.
Remember that if the spring is fixed at one end there are no frictional losses, as it doesn't move.
Friction also doesn't care about area, only the force and coefficient of friction. So if you have a bearing at both ends the friction is double that of one bearing, since the force at both ends of the spring is the same. If only one bearing rotates, the friction is halved. Because the angle the spring rotates is double with 1 bearing the same amount of losses occur. Both bearings need to rotate of course for this to be true.
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312 xt95324 xt100
356 Xt105
That was on the MP5 and I lost just under 20FPS going to one bearing from 2 so they would be a bit higher with the 2 bearings.
Progressive springs are designed to have the coils close up and (they would not be progressive if they did not) you will end up with a spring that wants to bend in the middle if you heat up the middle of it to remove the springiness.
If you really want to shorten a spring don't cut any off, pop it in a cup of water leaving the 15mm( or whatever you want to shorten the spring by) poking out and heat up the end with a propane o butane torch nice and quickly to a cherry red colour. Let it cool in the air. Then compress it on a long bolt to shorten it. You can repeat the process if you need to. I've never really understood why people cut the spring at all.
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Ultimately the thing that determines the strength of the spring is the force needed to compress it when installed and compressed in the cylinder.
You can have a long weak spring that gets pre compressed on installation and will be the same rating as a short strong spring which gets pre compressed less. They are all of similar length with variations of up to 25mm from those I have.
2 minutes ago, DanBow said:No.
Then that option is not available to you.
It's not the length that matters but how it's used.
I bought a selection of AKs springs when I was trying to get the right fps on the MP5
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A certain rated spring takes into account the length of the spring to arrive at the strength the spring will be used at.
For example you can increase the strength of a spring using spacers to pre-compress it or it can be longer than another spring with same spring constant which ends up pre compressing it when installed. In fact all the springs seems to have a degree of pre compression when installed.
For springs that are the same length they need to be stiffer, thicker wire or some such. Looking at the springs I have what seems to happen is that some springs are just longer than an otherwise identical spring, until you need to use a stiffer material because you'll run out of room to compress it.
Springs are cheap enough, I wouldn't bother cutting one. Take off a bearing at the guide end if you have one on the cylinder head perhaps, you don't need 2 bearings.
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Are all those bearings the same width? I use some 3x8x3 bearings and they do protrude and the one under the selector plate needed the plate relieving, but yours look wrong. One flush and one not is weird. i think you'll need to open it up again...
Select 3mm ID and you'll see 2, 2.5, 3 and 4mm widths.
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LOL, it's not weight, it's mass. Then yes, 2k extra for you. Altho the hop works to counter the weight of the BB so i guess either would work...
Motor Height Adjustment Screw.
in Electric Guns
Posted · Edited by Sewdhull
That's the idea but you have to have pinion height above the bevel gear set correctly too otherwise the noise is not related to the meshing but rubbing on the bevel shaft or always being unmeshed.
This why is can never seem to change much or finding the sweet spot is Impossible sometimes