8LikesKyosho Ultima RB5 Thread
10-18-2007, 11:04 PM
#2251
10-18-2007, 11:11 PM
#2252
10-18-2007, 11:38 PM
#2253
Areas of the various piston holes:
2B(2x1.3) = 1.3273mm^(2) x 2 = 2.65mm^2
2C(2x1.2) = 1.131mm^(2) x 2 = 2.26mm^2
3A(3x1.1) = .95033mm^(2) x 3 = 2.85mm^2
3B(3-1.0) = .7854mm^(2) x 3 = 2.35mm^2
It seems to me that the "softest to firmest" order would be:
3A, 2B, 3B, 2C
Correct...no?
2B(2x1.3) = 1.3273mm^(2) x 2 = 2.65mm^2
2C(2x1.2) = 1.131mm^(2) x 2 = 2.26mm^2
3A(3x1.1) = .95033mm^(2) x 3 = 2.85mm^2
3B(3-1.0) = .7854mm^(2) x 3 = 2.35mm^2
It seems to me that the "softest to firmest" order would be:
3A, 2B, 3B, 2C
Correct...no?
Last edited by Turbo Joe; 10-18-2007 at 11:52 PM.
10-19-2007, 12:35 AM
#2254
funny how math can bring the truth out of anything.
I submit that you are correct, sir!
However, while I see rather clearly that number and area wise, the 3A is the "softest" piston, fact is, the holes are smaller thus hydraulically packing up more than a physically larger 2-hole piston. If that 3A had 3 size 2B holes in it....different story, but regardless of area, I believe that hydraulically, larger holes pack up less, smaller holes pack up more.
My idea of a great piston would be:
2 #55 holes drilled in the black, much like a #1 AE piston then add 2 more holes perpendicular to those, making it a 4 hole piston, but the 2 new holes would have the combined surface area of a single #55 hole.
This way at high speed, the small holes will add a hair extra buffer in the pack-up off big jumps but still essentially make a 3 hole to keep the piston articulating in the sleeve. Also should have ehough resistance to keep the car on top of the bumps, but still allow it to ride up and down with full action.
I'll get right to work on it....lol
I submit that you are correct, sir!
However, while I see rather clearly that number and area wise, the 3A is the "softest" piston, fact is, the holes are smaller thus hydraulically packing up more than a physically larger 2-hole piston. If that 3A had 3 size 2B holes in it....different story, but regardless of area, I believe that hydraulically, larger holes pack up less, smaller holes pack up more.
My idea of a great piston would be:
2 #55 holes drilled in the black, much like a #1 AE piston then add 2 more holes perpendicular to those, making it a 4 hole piston, but the 2 new holes would have the combined surface area of a single #55 hole.
This way at high speed, the small holes will add a hair extra buffer in the pack-up off big jumps but still essentially make a 3 hole to keep the piston articulating in the sleeve. Also should have ehough resistance to keep the car on top of the bumps, but still allow it to ride up and down with full action.
I'll get right to work on it....lol
10-19-2007, 05:40 AM
#2255
I would think it would be pretty easy...albeit time-consuming...to test out which one offered the most damping.
You could just run the back-to-back against each other on a Losi shock tool and you could get a "piston X has more pack than piston Y" chart going...just try the various combination against each other and I'm sure you could tease out the results. Multiple trials would be good (maybe 2-3 of each) to account for slight variances in build...but I would think it would be easy to see what was what.
I'm still thinking that area = flow or smaller area = less "pack" and that the order is messed up to allow for standardized holes (drills) with finer adjustment points...but I have no way to know if that's really the deal.
You could just run the back-to-back against each other on a Losi shock tool and you could get a "piston X has more pack than piston Y" chart going...just try the various combination against each other and I'm sure you could tease out the results. Multiple trials would be good (maybe 2-3 of each) to account for slight variances in build...but I would think it would be easy to see what was what.
I'm still thinking that area = flow or smaller area = less "pack" and that the order is messed up to allow for standardized holes (drills) with finer adjustment points...but I have no way to know if that's really the deal.
Last edited by Turbo Joe; 03-04-2008 at 10:29 AM.
10-19-2007, 06:44 AM
#2258
Areas of the various piston holes:
2B(2x1.3) = 1.3273mm^(2) x 2 = 2.65mm^2
2C(2x1.2) = 1.131mm^(2) x 2 = 2.26mm^2
3A(3x1.1) = .95033mm^(2) x 3 = 2.85mm^2
3B(3-1.0) = .7854mm^(2) x 3 = 2.35mm^2
It seems to me that the "softest to firmest" order would be:
3A, 2B, 3B, 2C
Correct...no?
2B(2x1.3) = 1.3273mm^(2) x 2 = 2.65mm^2
2C(2x1.2) = 1.131mm^(2) x 2 = 2.26mm^2
3A(3x1.1) = .95033mm^(2) x 3 = 2.85mm^2
3B(3-1.0) = .7854mm^(2) x 3 = 2.35mm^2
It seems to me that the "softest to firmest" order would be:
3A, 2B, 3B, 2C
Correct...no?
10-19-2007, 07:43 AM
#2259
LiPo Battery Weight
Finally got my project done! Made them out of 304 Stainless Steel, grinded and de-burred the edges and put a sweet finish on them. Made them at 4.5 oz (you can trim some off to fine tune the weight to your liking). They are the same footprint of the Orion LiPo packs. Keeps the weight where it is supposed to be, in the battery box (and keeps the CG nice and low)!
Last edited by johnnyboy; 01-03-2008 at 11:36 AM.
10-19-2007, 08:23 AM
#2260
Finally got my project done! Made them out of 304 Stainless Steel, grinded and de-burred the edges and put a sweet finish on them. Made them at 4.5 oz (you can trim some off to fine tune the weight to your liking). They are the same footprint of the Orion LiPo packs. Keeps the weight where it is supposed to be, in the battery box (and keeps the CG nice and low)!
I only have a dozen of them if anyone is interested. $12.00ea [/spam]
I only have a dozen of them if anyone is interested. $12.00ea [/spam]
Looks good, i run the same spring setup. If i run lipo in the future i will take one but as of now its not legal.
10-19-2007, 09:28 AM
#2262
Tech Fanatic
iTrader: (8)
Now if I could jsut make a spread sheet to improve my driving I'd be on to something!!!!!
Anyway, this is good stuff. See if you can get a renolds number formula from the professors.
10-19-2007, 01:10 PM
#2264
On the drivers' stand the night before, I was thinking that the car was a bit too "stiff" for my liking. hehe.
Joe, you're right about accounting for area in square millimeters. I was oversimplifying it (and just thinking in "units") and forgetting that we're talking about circles here.
10-20-2007, 12:24 AM
#2265