|
|
Post by racket on Dec 7, 2015 19:42:11 GMT -5
Hi Mark Last job on the shaft tunnel , machining the groove for the silicone O'ring that seals the shaft tunnel innards from the P2 pressure , a tedious job getting the right amount of O'ring sitting proud of the metal so that the parts slip together relatively easy but enough rubber to seal , it seems like ~0.005 - 0.006" both axially and radially gives a nice amount proud of the surface .  The NGV and diffuser push on firmly once a lick of spit is applied to the O'ring , and the securing screws need a quarter turn to squash the axial bit and seat home . Cheers John |
|
|
|
Post by smithy1 on Dec 7, 2015 20:15:33 GMT -5
I hope that's a measured and calibrated amount of "a lick of spit"..! ;-)
Nice job.
BTW...I received the starter socket yesterday...thanks muchly indeed..I shall return the favor one day..! I should be able to make something similar...might try brass or ally depending on what I've got laying around.
Cheers,
Smithy.
|
|
|
|
Post by racket on Dec 7, 2015 21:19:17 GMT -5
Hi Smithy
LOL.......yes, only taken from the very end of the tongue ;-)
The jobs are starting to get less and less , the next one is probably the turbine wheel exducer shroud/jetpipe stub and mounting V band flange , maybe get that done by Christmas , then only the outer can next year .
A thin sheet ( 1mm) brass "socket" would probably be strong enough to spin the 6041 , that way it won't obstruct the comp entry too much after spoolup.
Cheers
John
|
|
|
|
Post by pitciblackscotland on Dec 7, 2015 22:00:49 GMT -5
Hi Mark Last job on the shaft tunnel , machining the groove for the silicone O'ring that seals the shaft tunnel innards from the P2 pressure , a tedious job getting the right amount of O'ring sitting proud of the metal so that the parts slip together relatively easy but enough rubber to seal , it seems like ~0.005 - 0.006" both axially and radially gives a nice amount proud of the surface . The NGV and diffuser push on firmly once a lick of spit is applied to the O'ring , and the securing screws need a quarter turn to squash the axial bit and seat home . Cheers John Hi John, Thanks for that, I am taking notes, as you said to me take your time and do it step by step.  Cheers, Mark. |
|
|
|
Post by smithy1 on Dec 8, 2015 0:25:06 GMT -5
Hi Smithy A thin sheet ( 1mm) brass "socket" would probably be strong enough to spin the 6041 , that way it won't obstruct the comp entry too much after spoolup. Cheers John I'd like to make it a little more robust than 1mm....maybe 2mm just to be safe....it needs to be able to handle ~30k..!  Smithy |
|
|
|
Post by racket on Dec 8, 2015 0:42:54 GMT -5
Hi Smithy
LOL,.............You're treating the 6041 too kindly , she should be OK with only 20,000, I only needed 22K for the 10/98 engine with its "tight" thrust bearing .
Yep , I'll agree with the 2mm ;-)
Maybe look around for a thin tube spanner , bit like a tube sparkplug spanner .
Cheers
John
|
|
|
|
Post by racket on Dec 8, 2015 22:41:56 GMT -5
Hi Guys I think I might have found a possible freepower gearbox for the Fat Boy , its the Hydromec FA52 Shaft mounted directly onto a 40mm dia kart axle ??  6.57 :1 ratio , and because its a two stage redux with sufficient distance between input and output shafts theres room for a large axial C30 4th stage freepower wheel , and at only ~15 kgs -34 lbs in an alloy housing its relatively lightweight , output shaft to bottom of gearbox is only 4 inches so still some karting ground clearance with standard tires. Might just get a quote on this one  Cheers John |
|
|
|
Post by pitciblackscotland on Dec 9, 2015 0:56:24 GMT -5
Hi John, Mmmmm interesting  Yes get a quote on this box,this company is in ITALY  Cheers, Mark. |
|
|
|
Post by racket on Dec 9, 2015 1:33:06 GMT -5
Hi Mark
Yep , italian made , am making enquiries through their local agent in Sydney.
Heh heh , I really can't imagine what a turbine kart with 250 plus HP would be like to drive, but this silly old fart might just try and find out, maybe for my 70th birthday :-)
Cheers
John
|
|
|
|
Post by pitciblackscotland on Dec 9, 2015 4:28:35 GMT -5
Ahaaaa!!  Good one John. How about a turbine powered trike  Cheers, Mark. |
|
|
|
Post by racket on Dec 9, 2015 20:17:08 GMT -5
Hi Mark
The gearbox lends itself to axle mounting on a kart , and I've always felt I shortchanged the constructed of my 2 shaft kart by using that undersized freepower and a simple lightweight karting chain drive , it did show how easy it can be done , but it left a lot to be desired in the way of horsepower , 30HP vs 115HP as in the bike using the same gas producer .
Its probably time I build a proper 2 shaft kart that I can be proud of.
If the 12/118 engine actually works , then it might just be used for that purpose , ............its early days , gotta get the engine finished first .
Cheers
John
|
|
|
|
Post by enginewhisperer on Dec 9, 2015 21:07:28 GMT -5
I'll keep collecting kart parts then |
|
|
|
Post by smithy1 on Dec 10, 2015 17:53:57 GMT -5
I'll keep collecting kart parts then Oi...You beat me to it....I was going to say the same thing..! I could "manipulate" the 6041 beast into a fair HP machine one day, I have 3rd & 4th RR250-C20B wheels at home just waiting to be fitted to something....but I still like the noise from the fire-breathing pipe..! Smithy. |
|
|
|
Post by racket on Dec 10, 2015 18:27:38 GMT -5
Hi Smithy The 4th stage wheel from the C20 is what you'll need for "full" flow . BUT, .......LOL, you know I love buts, ........ if you want both noise and good acceleration then maybe a split system with say a 50-50 split of the gases out of the 6041 , half for the A/B for some noise whilst the other half to a freepower , ...................1.4 lbs/sec through a freepower will give you the best part of 100 hp . .............and a similar amount through the A/B should produce some noise . Maybe go for the bigger gear ratio of 8.82:1 and use a third stage wheel , I used a third stage on the old bike with a flow of ~1.8 lbs/sec . The 6041 won't know the difference between what you now have and a split system as long as the "backpressure" stays the same . I'm dealing with this guy for the gearbox , current quote is ~$1,100 including GST. Geoff Baxter ENGINEERING MANAGER NSW SWB Plus Reliability Services Unit 4, 8 Cooper Street Smithfield, NSW 2164 T (02) 9616 0000 F (02) 9616 0300 M 0488 915 550 www.statewidebearings.com.au FA52 Shaft mounted helical gear box. - Solid input shaft - 490Nm output torque rating - Ratio, to be confirmed ............(I need the 6.57:1 ) - Output hub Dia. 40mm, on request. - Torque arm available if required Your cost $995.00 + GST Delivery, Allow 14-16 weeks to source gear head from factory in Italy. Could deliver in 4-5 weeks however this would involve air freighting components and extra costs would be incurred. The cost is "reasonable" as just the set of 2 gears for Andrews bike set me back ~$400 some 6 years ago , then there was all the hassles making patterns to get the cases cast , then machining them and making the shafting , etc etc etc , if I can get a suitable lightweight gearbox for $1,100 its fair , all I need to do is fit some oil jet lube and make up the freepower shafting and its "special" bearing needs. Being a shaft mounted gearbox , theres no mounting problems , just slip over a 40mm axle , I'll probably need a solid bespoke one made up to take the torque . Heh heh , talking about torque , if 250 HP at the axle at ~4800 rpm works out at ~275 ft lbs , but as a freepower produces ~twice its max rpm torque at stall , that 275 ft lbs will be doubled to ~550 ft lbs , but as kart wheels are only 12 inch dia , so a 0.5 foot radius between axle and road , the 'thrust' will be ~1,100 pounds at takeoff. So far things are looking like they might work :-) Cheers John |
|
|
|
Post by smithy1 on Dec 10, 2015 20:03:31 GMT -5
Hi John, ~$1000-$1100 for a decent gearbox which is essentially ready to "bolt-on" is a damn good deal IMHO....We'd be hard pressed to make one that cheap....as you mention, the cost of just the gear-set let alone, the casting and set-up costs/time etc....easily outweighs that cost. Would certainly save on a lot of ball-ache when it comes to casting/machining/measuring, sourcing parts/materials etc... A solid 40mm axle will easily take the torque...the tyres will break traction before the axle even thinks of twisting or breaking. Most car axles are less than 40mm, even the high HP jobbies. I did a quick "back of the envelope" calculation, the torque/thrust at take-off with 12" wheels will be just shy of 1100lbs....!! So she's gunna go...and go damn hard....and an axle with 12" dia tyres at 4800rpm, you'll be doing close to 275kmh..!  Smithy. |
|
Yes get a quote on this box,this company is in ITALY 
Good one John. How about a turbine powered trike 
