One helpful tip, rather than laying it on its side on the ground suspend it in water as well. So much pressure its only a tiny difference but when you suspend the product under water both sides come out near perfectly even.
Very COoL. Thanks for showing the failure mode... I had no idea how it would respond under that pressure.. I''m not as freaked out.. was pretty mellow. Beyond super cool racer and a GR8T tank build. Thanks!
Agreed, but a pinhole failure could have been a different story. Had one coworker get two fingers severed off and had to have a hand amputated from excessive tissue damage from injection. Not downing you just a little food for thought. There called accidents not "On Purposes"...did like the video, pretty cool process. Be safe brother!
I think if instead of thinking of this as two flat sheets .... take one flat sheet and weld a 1/4 inch high vertical "wall" all around it... and then weld the other flat sheet to the other edge of the 1/4" wall..... you could modify a portion of the wall to be wide enough to accept your gas cap.... the gas cap section might be thicker so it stays flat under pressure ... and you could use that flat spot for you pressure hose connection point. I think you are doing outstanding work here !!
Thanks Jim, the reason I had to make this first 2 sides and then split is that the finished tank needs to be in 2 parts (flat top, and one part on each side of the frame) I also had to build a internal oil tank and manual oil pump housing before closing it up :)
Splitting at the welds is as expected due to lose of malleable property. Ideally welds should be heated with propane gas torch not with acetylene torch. Furthermore, welded area is far more thicker, uneven stretch will occur.
By 1929 you missed the boardtrack era, most" murderdromes " were banned, excluding Bear Flats and Fields Follies! So to say you have an original is purely nostalgic fantasy...good day!
Flat tracks and and board tracks aren't the same thing. We still race flat track races, indian and harley davidson still race american flat track. There is a flat track by the house my dad grew up in and they still race there like they have since it was built in the 30s by farmers who I could only guess needed something to do.
Why not make a pair of steel frames from two 1/4" or 3/8" sheets large enough to cut the tank outline out of the center leaving at least 3 or 4" around the tank. Then clamp the 2 aluminum sheets between the steel frames with bolts spaced around the edge through the stack. The varying weld thickness, strength, heat and hardness of the edge welded method looks like potential problem. The steel frame may be more work for a single tank but could be re-used for a number of tank sides. The steel frame should allow cleaner straighter edges and make welding the aluminum center band easier. How hard was the aluminum? Can you anneal the sheets and improve the process? Expand in several steps with annealing between each pressure cycle may allow better and more consistent shaping.
For a one off this method is much faster and easier and cheaper than manufacturing and using a frame. Annealing will help but with the amount of bending along the weld line, approaching 180 degrees at the greatest point, it'll take multiple annealing cycles in an attempt to mitigate a single of the almost guaranteed multiple weld touchups that'd be necessary anyway. By just accounting for the bend in the initial cut profile design and pumping till it pops you can quickly, and I mean in 20 minutes, get half the way to a completed item. If you can predict and account for the rupture location and pre-empt unnecessary weld touch ups you can get almost 90% of a completed item in that same timeframe. Doing it this way ensures an acceptable centre line while eliminates the need for and thus hassle of manufacturing the frames, bolting the frames together and apart when creating the halves one by one, cutting off excessive flange material, creating a specialty fixture to hold or without a fixture somhow aligning and holding, then spot welding, then realigning/adjusting, and then welding solid the two halves of a semi completed tank for a nicer centre line. It's easier, cheaper, and quicker to make multiple tanks with slightly different profiles and seeing which one fits better on the project than it would be for creating the frame. Now if you needed to make 50+ the frame would be the obvious choice.
If you think stand beside while pressurized is dangerous, you do not understand the physics around it. Liquids have no expansion, and the pump flow is very smal. A blow out could in worst case cause 0,5-1 liter of water beeing spilled on your shooes...
janbvik its not the water that is dangerous, its the potential for metal fitting breaking and shooting high pressure shrapnel. It can kill you. Put a half empty aerosol paint can in a fire. Are you afraid of 6 ounces of paint? Come on...man up.
you should have some sort of valve to make sure there is no air in the tank while preassuring it. Air do compress alot as you know, and airpockets could actually be quite dangerouse in a situatiuon where you're standing next to it.
OK, thanks for the video - one more thing is off the list - what I wanted to try out my self. Without good result as seen here and point too. I cant believe you actually used this "thing" as gas tank - it is ugly as hell .... Wooden mold and shape metal by it then weld pieces and that's it... Yes, it takes some time but result is good. Cheers
In this situation the aluminum gets bent to the greatest degree along the weld seams as it is filled. The bending primarily creates "yield limit"/"stress fatigue cracking" along the weld line, and that's why it leaks there first. The pressure induced bending of the container along the weld line compromises it before the pressure induced stretching factor "tensile limit/strength" really comes into play, because of this it would fail first even if it's material thickness/strength was equal to or possibly greater than that of the hose/pipe. Assuming all bending/cracking are accounted for the system will fail where it is weakest and this particular hose is designed and so able to handle that amount(whatever made it rupture) of pressure.
Air compresses. If you have air in there when you start pressurizing it you are potentially creating a bomb. Fluid does not compress, it will not cause your part to explode.
All gas for metal forming is dangerous and difficult to control, if a weld or f.ex a hose cracks, the expansion of gas would be gigantic and deadly. Doing this with air would need 80-90 bar air pressure, you need a scuba air compressor, long load time (30 minutes) , and fatale danger if a weld cracks. You also need an outside mould if the forming (liquide or gas) should be done by "shock" in terms of rapid filling.
Great job! (Sorry. First song really sucks... ;-) ) I´m triyng to make my second gas tank. First attempt = complete failure. Question: what are you using for pumping water? Sounds like one of those car washing mashines... Metal gauge? Thanks for share. Great job! Keep on posting!
The water pump is a standard high pressure washer (100-120 bar) Use as small as possible, you don`t need a high volume capacity, only the pressure. The plates are Aluminium NV-5083 H321 3mm thickness
Salam/Hi. "Fluid forming" a tank seems common sense; maybe heating a little its high curvature spots or the whole thing near an open oven would have helped; injecting a hot fluid may also be an idea. Regards.
Good thinking... However... The water inside would immediately absorb any and all applied heat. Even at pressure the water would preventing the metal from ever being over approximately 286 degrees F..(The ensuing thermal pressure would rupture the assembly.) Even if one were foolish enough to heat the pressurized water to over 220 degrees, the water would immediately 'Flash' to steam when the forming vessel ruptures causing Severe burns to anyone near. In production level manufacturing, a multi-piece mold form is used to constrain the substrate metal to conform to the desired form factor. It Really is a fascinating Process. Regards, Bob
When you have access to a tig why wouldn't you just build a buck and form the aluminum to it..anealing as you go..with hydroforming you can't aneal and it stretches and puckers without a form to expand to...just a bit of experience talking here.
Thank`s :) Your english wheel and and a hammer is still a good start if you are hydroforming a solid tank. In this example the tank should be in 2 parts with internal oiltank bulit in later, so cutting was planned. On a single body tank, use the hammer and english wheel to curve the sheet edges so much that the sheet ends are perpendicular in the weld joint. Then the pressure will not work against the weld, and you can play around with higher pressure and more stretch. Good luck !
@@t7emonic792 And you must not understand the physics behind Bernoulli's theorem, the potential of severing an appendage or blood poisoning might be slightly dangerous.
