Designing my first build... Help!

[bread]

I understand building a frame around a single beam down the middle, but I want the seats to be nice and far from each other.

I want to share with you guys that I got most of my deign inspiration from this instructable for an ev platform. Read it and look at his design, it will look similar to mine.

http://www.instructables.com/id/Electric-Vehicle-A-simple-lightweight-EV-platform-/?ALLSTEPS

 

[OzFab]

Are you worried my frame design is not going to hold, even if I use the 1 1/2" steel tube?

No, not at all, properly engineered, it will be fine...

I want to share with you guys that I got most of my deign inspiration from this instructable for an ev platform. Read it and look at his design, it will look similar to mine.

http://www.instructables.com/id/Electric-Vehicle-A-simple-lightweight-EV-platform-/?ALLSTEPS

I understand the concept & why you chose the design but I'd like to point out one significant difference: The vehicle in the link is built in three dimensions, length, width & height, your design is, essentially, two dimensional, it has length & width but, no height; the third dimension is where the strength comes from...

Remember, the strongest shape in the universe is a triagle... it has three aspects

 

[bread]

Alright, excellent, thank you everyone and I will return when the build begins!

 

[mckutzy]

What are you planning to use for the front axle spindles? Those wheels arent a real common buggy tire, and the mounting is most likely going to need something to the original type of stub axles like on the trailers already.
As for the rear axle you are still going to need a bolt flange with a keyed hub to mate with the size of axle, of choice.

A 5 bolt will be easier to find a flange for a hub, but other bolt patterns will be difficult(6 and 8) if not non existent.
If one has to make the flange by hand, get ready for some real layout challenge, and hope you have a lathe and/or mill to help. I know and I did make one on my bike.

 

[bread]

Thanks for the comment, for the front I plan to use normal go kart spindles with single flange and a 2 13/16" bolt pattern. Of course, that pattern won't fit a trailer wheel, so I also plan to make custom hub adapters to transition to the wheel. For the rear I will do the same thing, but of course with hubs without bearings, ones with set screws.

I've attached pictures of what I will buy.

 

[bread]

I'm starting to worry about pricing, the costs do add up fast, I'm wondering if I can use a 5.5hp tecumseh from a snowblower to power this car. Will this have enough power to push two people? I have one lying around in the shop. The strange thing is it has a 7/8" crankshaft, so there are no normal clutches made for this size. My question being: can I just use a belt drive torque converter clutch because those have a 7/8" bore? By using a belt clutch, i'll just make the rest of the drivetrain belt as well.
Can I do this?

I've never built something of this size before so I have many questions.

 

[mckutzy]

Do you have a lathe? Those adapters are goin to be a real challenge with out it, as there is no way to assert concentricity between the patterns and bore.

 

[bread]

Just checked, its easy to find 4in bolt pattern go kart hubs and corresponding bolt pattern on 16 in utility trailer wheels. I don't have a lathe, however.

Can anyone answer my engine and clutch questions in my previous reply?

 

[jeeperjoel]

concerning the power it's going to depend on how fast you want to go, you could gear the cart really low and have plenty of power, but you'll lose top speed, as for the engine you could probably find a different crankshaft that'll fit it alot easier than making an adaptor, but now you're spending $ on it... not just the crank, but matching torque converter, as the crank you'll find will be most likely 3/4" output, the engine you were planning on has a 1" shaft so when you do decide on more power that's a part you'll have to buy again, a 3/4" bore comet clutch is generally found on a 30 series TC, you can get a 1" bore clutch for a 30 series TC, but it won't be able to take the power of the larger engine should you decide to step up later, for that you'll need a 40 series unit... for 1 person a 5 hp range engine works good, for 2 people not as much fun, i'd stick to original plan, the build will take time, get metal for the chassis, wheels, everything you need to make a roller first, probably still will have enough for the engine, that'll get you started, as you build buy a part here and there, rome was not built in a day lol my buddies jeep build took 4 years, not driving it at all, of course it's not a go cart, but same applies

 

[bread]

so I just priced out framing materials and when added, those two things add up to a shockingly even $500 thats with shipping. This gives me $600 for everything else including whatever engine I end up using.

You are right, this project will take a hefty amount of time and thought.

... And here is a thought: could I use a 2 cylinder motorcycle engine from craigslist or something?

 

[jeeperjoel]

yeah, sure could, will have to build engine mounts, find a chainring and "hub" that fit the axle you decide to go with and sprocket on engine, most likely add a clutch pedal and shifter/linkage it's do-able

 

[jeeperjoel]

where is kamino? no steel supply there? i got one down the street, the price of your metal seems pretty high....

 

[Poboy kartman]

KAMINO????....Yes...while geography is my weakest subject.....I'm clueless.....

 

[jeeperjoel]

the only kamino i know of is camino CA, east of placerville....

 

[bread]

I was going to get my steel online at http://www.metalsdepot.com/catalog_cart_view.php?msg=#

Is it cheaper at an actual supplier? $241 is expensive for the steel? The wheels (all 4) were $222.

All my previous projects, I would get steel from home depot. I would buy black steel pipe in 10 foot sections.

Kamino is farm neighborhood in Carroll county, TN

 

[jeeperjoel]

the price for steel isn't too bad, didn't realize you included wheels in that estimate...

 

[bread]

Do you recommend buying steel online or going to a supplier?


Frame design change

I have also decided to make the seat rails 1" tubing and the subframe the 1 1/2" tubing

 

[jeeperjoel]

you'd have to check prices, local place here delivers free if you spend over 200$, might save a few bucks on shipping

 

[bread]

Thanks for the info again.

Back to the subject of drivetrain: My question still has not been answered, can I mount on of these

http://www.ebay.com/itm/40-Series-T...H_DefaultDomain_0&hash=item20d7d0b46a&vxp=mtr

directly on the crankshaft of my engine, then have a belt and another pully in the axle?

 

[OzFab]

No, that's a driven pulley; it goes on a jackshaft with a sprocket, which then connects to the axle sprocket via a chain.

For the engine shaft, you need a driver... or find a complete torq-a-verter

7/8" is a strange size for an engine PTO shaft, they're usually either 3/4" (for smaller engines) or 1" (for larger engines) although, there are many different sized & shaped shafts...

As gran_pann explained, for this purpose, the engine shaft should be 3/4" so it will need to be machined down & a new keyway cut; unless you have a lathe at your disposal, that could be expensive & may be cheaper to simply buy a 212cc Predator engine...