Propane Adaptor gone wild

[MadMax]

Originally Posted by W.K.Shuridys

I've found that the staking on the adapter body is insufficient to keep the probe captive for very long. At best the stakes will hold for a month of use and then wear down enough to allow the probe to push out with minimal force. I find that while mine are captive enough to stay in one piece during transport, the probe is pushed out of the body when screwing it onto the tank and needs to be pushed back in before filling.

Thanks for your feedback. I haven't seen this in my own testing, but nothing beats observations in the field unfortunately.

I'll adjust the design for a more aggressive staking tool.

[FOX_111]

While we are talking about the propane adaptor..

It would be nice for the next version to have a screwing protective cap.

I have a V4 adaptor and the red cap fall off too easely in my carry case/pocket...

[MadMax]

Sorry, I'm stuck with off the shelf plastic caps. I tried to find stocked caps that could thread onto a threaded bottle fitting, but couldn't find any that were economical. The nickel plating process is also rather harsh. Bottle fittings are tumbled in a drum during the plating process. An external thread would get pretty dinged up and not very thready in the plating process. I'm still looking for a better cap, but I think I'm stuck with the crappy red caps until I can afford a custom injection mould (beaucop $$$) which means that I have to be producing in the tens of thousands.

[PTE. Pyle]

mad max y not put a little grouve around the bace of the adaptor where the couver sits and find a cap with a little lip that would fit in that grouve similar to a tylenol bottel obveously not that extreem though

[MadMax]

no stocked caps with an undercut. I'm limited to what I can find that's a stocked item made by a cap making company.

[FOX_111]

would it be cheaper to machinate a cap out of metal?

[MadMax]

Originally Posted by FOX_111

would it be cheaper to machinate a cap out of metal?

Nope. A machined cap would be a third machined part which involvs a lot of raw material, and a lot of material removal (lots of stuff bored out the centre). It would probably make my unit costs go up by around 50% which means that my selling price would go up by the same amount. I don't think airsofters are willing to pay that much for an adaptor with the preexistance of much cheaper versions.

[Gryphon]

You're welcome on the feedback. If this is a new issue that you'd like to explore a bit further, would you like me to send back my adapter temporarily for inspection? I have a spare I can use.

[MadMax]

Thanks, but I can see how the stake marks could pushed out. I previously thought that they were deep enough as most of the adaptors seem OK. It's possible for me to dig in deeper stake marks. It just means that the press has to prang harder. It's nice to be able to thump with a light crunch with a hand press. However, it's not that hard to crunch a bit harder with a more aggressive tool either.

[Gryphon]

It may be asking much, but what about a thin set screw though the side of the adapter body to mate with a spline on the nozzle? That would keep it captive but allow for removal for maintenance, replacement, etc. I imagine this would significantly add to the manufacturing costs though...

[MadMax]

the cost of the screw isn't much of an issue, but it does mean an extra machine operation after the bottle fitting is turned on the lathe. One of the biggest factors determining the cost of a part is number of setups. If a CNC machine can crank something out in one setup it means that there is less operator time. For a part like the bottle fitting, setup time is significant compared to the time that the machine is actually spinning.

The probe requires two setups. One side is machined from long barstock and they're popped out automatically. There isn't much operator involvement as the first operation can progress fully automatically. To machine the mag probe end, an operator takes each part blank machined from long barstock and puts it in a lathe chuck once more to turn down the other end and drill the other half of the centrebore. Because of the second operation, the probe costs more than double the cost of the bottle fitting although the bottle fitting requires more material removal.

Consumer products are a PITA to design. you have to develop something that works well with little training. Error tolerant and failsafe. Durable and cheap. There's an adage I like:

You can have it good, cheap, or quick. Pick two.

Consumer products have to be good and cheap so I blow my brains out spending a lot of time in product iterations. V4 is actually V14 in my book. The worst part is that most of the ideas that didn't make it look quite plausible in thought. Once a proof of concept was hashed out reality bites and an unobvious problem kills it. The end result is the distillation of a few good ideas pulled out of a bucket of plausible but ultimately wrong bad ideas. The end result works for obvious reasons so it looks like a highschooler could design it. A lot of product design is acquiring a lot of "know how not". It's definitely exhausting.

[hattrick]

Buy one of the fatty (green) camping propane bottles. It actually locks the middle peice in. (Wont come lose untill you unscrew the bottom peice)

I may be wrong, but i have a silver on silver adaptor. (nothing special) As stated, it locks in nicly

[Goldman]

why not just make a cap that is on like a plastic string, like a canteen lid... you put the ring around the neck o the bottle first,then screw on the adaptor...

[MadMax]

I don't get to make my caps. My caps are off the shelf components. I'm not manufacturing in large enough qty to justify a custom injection moulded cap yet unfortunately.