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Re: New lakester build

Posted: Wed Aug 01, 2012 11:23 am
by RGV

Re: New lakester build

Posted: Wed Aug 01, 2012 6:41 pm
by AuotonomousRX
Great Model, but you don't need the balsa to keep the weight down :lol:

I agree about hanging in there.

I started planning a Hot Rod - then a Lakester - then a Streamliner - then I realised if i did build a Car I could not afford to get it there, so I ended up with a 250cc 2stroke :shock:

It is the best thing I've ever done,have a go.

The cars were going to be 4 cylinder powered and the Lakester and Streamliner designs/drawings were both rear engine to get as small a Frontal Area as possible. Low HP engine so Aero was critical to going as fast as possible.

Pete#866

Re: New lakester build

Posted: Tue Sep 11, 2012 1:14 pm
by walkingpace
There hasn't been much progress lately thanks to moving house and one hell of an electricity bill :shock: however I'm now in a position to get things in motion. There have been some changes to the design, thanks in no small part to the advice of some of you forum dwellers. Firstly I will be including the fancy wheel fairings which will place the car in the uninhabited fuel streamliner class (I didn't really want to compete with Goggles and Hedgash). Also I have revised the driving position, moving the seat behind the rear axle front engined dragster style, meaning I can get the drivers seat low without worrying about setting up a chain drive just yet. This still forms a part of the plan but my emphasis is on getting a functioning car as soon as possible and then working on the more complex engineering challenges to make it faster. The famous "redhead" streamliner is a big influence on the chassis design as it made use of this layout and is a beautiful and well balanced car (which has done 320mph :shock: )

As to the suspension issue, it will be included, but not for any of the usual reasons. My concern seeing as the front axle is a cast iron jobby, it that repeated high speed bumps will cause stress fractures which I won't know about until it fails (I seem to have misplaced my xray machine). I like the torsion bar setups used on a lot of dragsters however they are awfully expensive so it will be a more traditional transverse leaf.

The chassis design has been chalked onto the garage floor and I'm off to start cutting and welding.... 8)

Re: New lakester build

Posted: Tue Sep 11, 2012 7:55 pm
by RGV
At the last place I worked we did a lot of N.D.T. We used Dye penetrant inspection on some non ferrous metals. Cheap and easy to do but limited to surface imperfections.

http://en.wikipedia.org/wiki/Dye_penetrant_inspection

Dave

Re: New lakester build

Posted: Fri Sep 21, 2012 1:54 pm
by walkingpace
Turns out the font axle is forged and not cast (I didn't even know there was a difference until someone with knowledge of all things metallurgical explained the difference. I thank him for suppressing most of his laughter :oops: ) Anyway, stress fractures are not such a problem for a forged axle but now that I'm underway I'm not changing the plan. Suspension it is.... :)

Re: New lakester build

Posted: Sun Sep 30, 2012 12:19 pm
by walkingpace
Here's a couple of pics of the first chassis mock up. I've set it up front engine dragster style with the driver behind the rear axle. Wheelbase is 100". It looks as though the upper control arm mounts will need to be ground off the diff for leg clearance but otherwise I now have a good idea of where things need to go.
Image

Image

these are the WWII aircraft guages mentioned earlier
Image

E class streamliner

Posted: Tue Oct 02, 2012 9:49 am
by walkingpace
Thanks to the long weekend I've been able to get a little bit more done. The two lengths of steel which I had the metal supplier cut for chassis rails turned out to be 5mm different in length. I would have thought cutting accurately with one of those huge, extremely accurate saws would be easy but there must be more to it than meets the eye...

Anyway they have now been evened up and I've cut out the front and rear cross members. The wheelbase that started at 98" when first drawn up, then grew to 100" when chalked onto the garage floor, and has now grown to 103" in metal. It seems like every time I play with it it gets bigger..... :roll:

The next job will be welding it all together then making a spring perch and brackets to mount the front end. Will also be getting the roll cage tubing bent up very soon.

Re: E class streamliner

Posted: Tue Oct 02, 2012 9:55 am
by Greg Watters
Why sitting above the tailshaft ?
wouldn't it be much lower if you were in front of the motor, and potentially safer ?

Re: E class streamliner

Posted: Tue Oct 02, 2012 10:39 am
by walkingpace
Greg,

The design has changed a bit from the first model. Drivers seat will actually be behind the diff with legs slung over the axle like the old dragsters. As for safety there will be a significant scatter shield over the back of the diff. Not sure I'd be brave enough to run without it :shock:

Re: E class streamliner

Posted: Tue Oct 02, 2012 5:17 pm
by zork
The biggest problem with front engine rails was that they could not breathe oxygen when the motor blew.

Re: E class streamliner

Posted: Tue Oct 02, 2012 8:35 pm
by Greg Watters
I have sat in and launched a front engined rail up a driveway,even then with a 1/4 " sheild and seat between me and the diff.... i was nervous,
But the launching part was real good :D

Be looking forward to reading about your "real good" when its done :D

Re: E class streamliner

Posted: Wed Oct 03, 2012 11:56 am
by walkingpace
At the moment it's fun to just sit on the clamped together chassis and play broom broom games like a little kid :D I can't imagine how much fun it will be when I eventually get to drive this thing.

Don't worry Zork, if the motor turns into an expensive grenade I'll probably be holding my breath anyway :o Plus methanol smells nice. As my brother once described it, "it's like someone put a gummy bear in a toaster"

Re: E class streamliner

Posted: Wed Oct 03, 2012 12:02 pm
by BIG GAZ
I can guarantee the novelty will wear off after getting in and out a million times before it is finished. At this stage I can only assume that it is all worthwhile once it is on the salt in race mode.
Gaz

Re: E class streamliner

Posted: Sat Oct 06, 2012 10:27 am
by momec3
I'll second that Gaz :lol: :lol: :lol:

Chris

Re: E class streamliner

Posted: Thu Oct 11, 2012 11:28 am
by walkingpace
Greg Watters wrote:I have sat in and launched a front engined rail up a driveway,even then with a 1/4 " shield and seat between me and the diff.... i was nervous
Thanks Greg, now you've made me nervous. I'm really not sure I trust that little 8 bolt GM character enough to rest my nether region on it then hold the throttle wide open. I'm now shopping for a 9". There is actually another justification for this as well.
The pinion on the GM diff is offset 20mm to the right and I had planned on shortening one axle to sort this issue out. Trouble with shortening one of these things is...you can't.

Captain tightwad at holden only hardened just enough of the axle to cut a spline in it then threw it on in there, plus on inspecting the axle, the tips of the spline actually sit slightly proud of the general axle width. I can only assume the splined bit was a touch wider than the rest of the stick before it was machined. The only option would be custom axles and that would be a great big waste of money on this thing.

I know a 9" is not necessary for the modest power output I can expect and the limited grip offered on the salt, but the thought of shrapnel coming back through that little tinplate cover causes the sweat to bead on my forehead.

....now where did I put my credit card.....