Little girl's off-rail industrial hand car

[EGAZ]

Ssshhhh..... I won't tell no one.

[BoyScoutGirl]

Thank you guys, both for taking me seriously in this endeavor and for giving me caution when I might be getting in over my head.

As you can tell, I am the least engineer-y on the team. I'm good for things like "Does Google know reasonable angle of inclination for a playground see-saw?" and sketching cartoon layouts and "Let's put all the parts into a spreadsheet to estimate costs given these three scenarios." My major goal for this project, apart from building a fun and functional piece of mobile art, is to learn fabrication skills I currently don't have.

eldergeekaz, it's really sweet of you to offer, but I'm pretty far from Phoenix, unfortunately. I do know of a metalworks where I'll be taking welding classes, so you can rest assured I'll have professional training.

I just got off the phone with one of my guys - turns out he's done both stick and MIG welding and owned a gas shield MIG welder for a while before moving out west. He'd be happy to own the one linked, if it's in good shape. We're currently investigating, so thank you, Capt., for the tip! If we do buy that welder or similar, we'll hold onto it for future projects too.

As anticipated, all (or most) parts to be welded will be from new steel, and we currently don't anticipate anything thicker than 1/8".

[Captain Goddammit]

One of my tricks, if you're using a wire feed like that on thin metal, sometimes it's easier if you plug the machine in through an extension cord, to intentionally reduce power.

[EGAZ]

I just got off the phone with one of my guys - turns out he's done both stick and MIG welding and owned a gas shield MIG welder for a while before moving out west. He'd be happy to own the one linked, if it's in good shape. We're currently investigating, so thank you, Capt., for the tip! If we do buy that welder or similar, we'll hold onto it for future projects too.

You should be good to go then. and it will give you practice time!

I knew you were in SD. It would have been fun to help out. I haven't had a good welding project ion awhile.....

[BoyScoutGirl]

If I were staying in San Diego I would drive out to Phoenix over a long weekend to learn welding in a heartbeat! Unfortunately, I'm moving quite soon to that incipient nation of Cascadia...

[Captain Goddammit]

Oh I thought you were in Seattle...

[Tiahaar]

Would you be interested in wheels like this?

Honda Goldwing front wheels w/tires or others like that can be had for @ $50 or so on auction, or there are a couple motorcycle salvage places down there around SD, never been to them but they might have a serviceable set. It takes a metric size axle with the stock bearings, though I have pressed them out and put SAE sizes in.

[BoyScoutGirl]

Oh I thought you were in Seattle...

Wait... Cascadia is a real place? I thought it just meant "Pacific Northwest region," of which Seattle is a part.

Tiahaar, that motorcycle wheel+tire looks like a great combination of the visual aesthetic we want plus not the cost of new Skyways. One of the guys in the group is a motorcycle nut, so I'll ask him about it. He mentioned motorcycle parts once, but it's a good reminder. I think the problem point was finding a matching set of 4. Maybe I just need to find/make a cooler hubcap for the trailer tires...

[Dr Helix]

[quote="Jackass"]I've never welded stick, just light- medium duty MIG stuff, mostly with the millermatic 175. It does everything I need, and then some. Great machine. I tricked mine out swapping out the stock cord for an 8 AWG 16' cord, now I rarely need an extension![/quote

This is the ticket.

[Captain Goddammit]

Cascadia is about 100 miles from Portland. It's a real place.

[Skuzzy61]

That 175 is a good machine jackass. I have a Lincoln 175 and a Hobart 230. I am liking the Hobart, especially on heavier stock.

For thin gauge stuff, I'll use the 175. The smaller wire flows great. Anything over .0625 inches gets the Hobart.

I have a couple of gas bottles. CO2/Argon for mild steel. Helium/Argon for stainless. I would like to use the Helium/Argon for everything, but it is pricey and only makes prettier beads for mild steel.

[ygmir]

Oh I thought you were in Seattle...

Wait... Cascadia is a real place? I thought it just meant "Pacific Northwest region," of which Seattle is a part.

Tiahaar, that motorcycle wheel+tire looks like a great combination of the visual aesthetic we want plus not the cost of new Skyways. One of the guys in the group is a motorcycle nut, so I'll ask him about it. He mentioned motorcycle parts once, but it's a good reminder. I think the problem point was finding a matching set of 4. Maybe I just need to find/make a cooler hubcap for the trailer tires...

viewtopic.php?f=56&t=67707&hilit=cascadia

[Ed Banks]

One of my tricks, if you're using a wire feed like that on thin metal, sometimes it's easier if you plug the machine in through an extension cord, to intentionally reduce power.

Not sure if you're joking, but this is not a good idea. Your welder will attempt to draw the same current, no matter what size wire you run to it. You're only going to create heat in the extension cord from all those electrons scurrying to get fed into the metal.

A longer arc length, running .030-.035" wire, faster travel speeds, stringers (no weave) are standard fare for sheet metal welding.

*edit*: Proper metal fit up is key as well, should be as tight as possible, but this is true with thin/thick material.

[Dr Helix]

When did everyone become a welder?

[ygmir]

hhmm I use .024 wire, sometimes reverse polarity on sheetmetal.

[Ed Banks]

When did everyone become a welder?

Last week, we all went and took/passed the 6G test. You didn't get the evite?

[Dr Helix]

When did everyone become a welder?

Last week, we all went and took/passed the 6G test. You didn't get the evite?

Have em'

https://www.facebook.com/Fergusonweldingservice/

[Captain Goddammit]

One of my tricks, if you're using a wire feed like that on thin metal, sometimes it's easier if you plug the machine in through an extension cord, to intentionally reduce power.

Not sure if you're joking, but this is not a good idea. Your welder will attempt to draw the same current, no matter what size wire you run to it. You're only going to create heat in the extension cord from all those electrons scurrying to get fed into the metal.

In theory you're right. But in actual practice, it's a trick that works great, taught to me by an almost 60 year old friend of mine who has been a pro welder since he was 18.

[Skuzzy61]

When did everyone become a welder?

You will never here me call myself a "welder". I have about 45 years experience and do not consider myself an expert. I learned on oxy/actly and an arc welder with stick. When MiG came along, it was manna from heaven.

I do have a critical eye for the weld though. I can tell a good one from a bad one. I have enough confidence to make my suspension parts from scratch (control arms, uprights, brackets...). So far nothing has broke.

[Ed Banks]

In theory you're right. But in actual practice, it's a trick that works great, taught to me by an almost 60 year old friend of mine who has been a pro welder since he was 18.

I never said it wouldn't work, I questioned the safeness of it. You're increasing the resistance of your circuit by choking it down, this will in turn create heat, heat causes fires.

[EGAZ]

No, not certified. But many decades of welding up trailers & ramps/gates, (open and enclosed), race car frames & components, headers, bike frames, Head-ache racks, etc. I have also welded black pipe at work in a past life (HVAC&R) for cooling towers and other low pressure closed loop systems with stick.

Solder, braze, gas weld, (with/without filler rod) Stick, (all positions) and MIG, (light to heavy). TIG is the only thing I have not had enough seat time to be good at. One day though.....

[Captain Goddammit]

It doesn't create as much heat as welding does...

[BoyScoutGirl]

I owe everyone an update. Not surprisingly, considering when inspiration struck, the hand car was not built in time for the 2016 burn. The hold-up was finding a suitable location to build on the timeline we needed. We have started purchasing parts and I've enrolled in a three-month welding course. We've even found contact info for a guy in the area who has built a hand car before. We plan to start building for real around January, after a few mock-ups.

Thanks to each of you for the input, critique, patient explanation, and banter. Onward!

[Elliot]

Thanks for the update!
It shall be fabulous!

[BoyScoutGirl]

First 3D-printed model. No steering or drive train implemented, but having a physical object in hand really helps us get a feel for things. Already we can tell that there wouldn't have been enough space for the lever, and that we'd probably like the wheelbase to be longer.



Note also that we're thinking of having a well cut into the deck so the wheels can turn. When going straight, we currently plan to have the inner edge of the wheel at the outer edge of the decking.

[burner von braun]

I'm glad to hear you are still pursuing your hand car BSG. It is a good idea. I understand how some projects end up getting shunted to the next year, Haha! It happens to me every burn. I have a particular project that I'm determined to bring this year after having to set it aside last time. And please do continue to keep us updated here, it is great fun following your progress.

[BoyScoutGirl]

Thank you, von Braun! I will endeavor to post more regularly; at the very least when we have something to show...

Second 3D-printed model, with longer wheelbase and shorter (3.5') lever. We dislike that the front and rear wheel wells aren't the same, so that will probably be changed in future iterations.




Modeling a front (inside) wheel on a turn to get an idea of turning radius. The white rectangle is the wheel. Green vertical dotted line is the axle, and green solid perpendicular lines represent the decking. The green 45 degree angles are ancillary to steering.

[Elliot]

Wow.
I just toss materials and components on the floor and throw sparks at it until it works.

[BoyScoutGirl]

...I just toss materials and components on the floor and throw sparks at it until it works.

Play and experimentation are certainly how the human mind learns best; they are the testbeds in which we grow intuition. I envy the ability to do as you describe.

Having developed very little mechanical intuition (so far!), my current strategy is to play and experiment on leetle plastic bits first. Later comes more considered experimentation with comparatively expensive metal parts where I have to pay by the hour for shop space and tool rental.

[Elliot]

Scout, you don't owe any explanation! It was just a wisecrack -- and also intended to express admiration for your technology and modern technology skills.
And... I ought to plan ahead better on my own Stuff.

Enjoy your weekend!