1/2a Pressure Bladder Help
03-13-2015, 09:39 PM
#1
Thread Starter
1/2a Pressure Bladder Help
Hi there. Just picked up a Norvel .049 AME tonight and am looking at running a pressure bladder on it. So, I was just wondering if anyone who has used these before or still does use them could tell me if 4mm i.d. by 6mm o.d latex tubing would be ok to use. Or do I need something else. Also, where could one pick up latex tubing somewhat locally, meaning what kind of stores would you look in. Thank you.
03-14-2015, 09:03 AM
#2
I just answered this in the other forum, but will repeat it here. What you have will work. Thinner wall is usually better for less pressure. It is usually available in medical supply stores. TSC has the larger 1/4" stuff which is OK for a .15 size. The Little Red Cap" at Lee Valley Tools works pretty good, but will not last a whole season. $5 or so for 20 of them. Kind of like a squirrel condom. http://aerohobby.ca/store/index.php?...index&cPath=11 has the larger .15 size too. MBS (model building supply) also has the fittings and plugs too as well as different line sizes.
Last edited by aspeed; 03-14-2015 at 09:05 AM.
03-14-2015, 10:46 AM
#3
Get fresh latex tubing from a fishing tackle store.
The size I use is 3/16" on the O.D. The length from the knot to where it is coupled to the silicone fuel line is about 1 1/4". The fuel line needs a short length of hard tubinginserted so that you can firmly tie the bladder on.
You can use tiny tie wraps, but I show fine stainless tie wire here.The fuel line is Sullivan small from Tower Hobbies.
The size I use is 3/16" on the O.D. The length from the knot to where it is coupled to the silicone fuel line is about 1 1/4". The fuel line needs a short length of hard tubinginserted so that you can firmly tie the bladder on.
You can use tiny tie wraps, but I show fine stainless tie wire here.The fuel line is Sullivan small from Tower Hobbies.
03-14-2015, 05:03 PM
#7
With the set up I show, 3/4 oz fuel is about the max before you weaken the tubing beyond it's elastic limit.
The wall thickness of the latex tubing is about 1/32"..so the I.D. is pretty close to 1/8".
I don't know why, but I think black works better than the yellowish stuff.
I like to use Monoject 2 oz syringes [found at the farm supply] and press a short length of brass tubing into the plastic syringe tip. You want to smooth [and radius] the outer edge of the brass tubing with a rubber knife honing wheel [if you happen to have one] or else use sandpaper.
The wall thickness of the latex tubing is about 1/32"..so the I.D. is pretty close to 1/8".
I don't know why, but I think black works better than the yellowish stuff.
I like to use Monoject 2 oz syringes [found at the farm supply] and press a short length of brass tubing into the plastic syringe tip. You want to smooth [and radius] the outer edge of the brass tubing with a rubber knife honing wheel [if you happen to have one] or else use sandpaper.
