15
Jun

Building an MG-TC pedal car: Part 4a

   Posted by: Mark   in Pedal car

Refer to the Introduction for links to all of the posts in this project. This is a continuation of Step 4.

About a week ago I was able to get both the steering and drive systems complete, which had been a hug hurdle for me. After some brainstorming with Dad and some poking around at the Orange Box, I found all I needed.

The plans had called for a galvanized pipe for the steering rod, flattened and bent up at the tie-rod end and fixed with a pipe flange at the other for connection to the steering wheel. I had a version of this completed, but was never satisfied with the roughness of the steering. Not only was it difficult to steer, but it wasn’t particularly reliable. So I ended up using a 3/8″ diameter piece of steel for the steering rod. At the bottom end near the tie rods, I bent it up, ground the sides a bit to make some flat surfaces, and used U-bolts to fasten a 1 1/2″ x 4″ section of flat steel. The tie rods bolt to this flat steel, and there is amazingly little play in the whole thing.

I had ordered tie rods with the ball joints, but the shortest they had were 11″, and I needed something around 8″ long. I used 5/16″x24 threaded rod (or all-thread), which is great because I have enough play to allow adjustment of each wheel separately.

P1020632

It’s not the prettiest steering ever created, but it works very well. The steering rod comes through a piece of scrap that I screwed to the front of the body because the original steering column hole was about an inch in diameter to fit the pipe called out in the plans. Once the grill is in place it should look much more clean.

P1020633

You can see the flattened sides of the steering rod. The U-bolts I had bought were pretty small, so I had to grind the sides of the rod to get them to fit. There’s no chance they can slip or move — they’re on VERY tightly.

And here’s a poor-quality video of the steering in action. The angle on the tie rods is a lot greater than I would have wanted, but at this point I’m not willing to redo it all. The kids could care less, and I just want to get it painted!

For the drive system, I had two problems: I couldn’t figure a way to affix the single drive wheel to the 3/8″ steel axle rod, and I didn’t know how to attach the drive rods from the pedals to the crank. Although I’m not yet convinced the lifespan of this solution is all that long, I ended up drilling a hole through the drive wheel hub and the axle, and inserted an “R” clip through the holes. My concerns with this are that the hole I drilled is pretty large relative to the small 3/8″ axle, and the hub isn’t really designed to handle the torque that can be applied by an excited child. We’ll see how long it lasts. So far it doesn’t show any wear, so that’s promising.

P1020641

Getting a picture of this was harder than I expected, and the sun was fading fast. In the picture above you can see the loop on the “R” clip. I still need to trim the axle, but I’ll probably wait for final, post-paint assembly before I do that. You can also see the colored label on the tire in this picture, which is another thing to fix in final assembly (all the other wheels have the blackwall point out, with the tire graphic hidden; yes, I have issues).

P1020642

It’s really tough to make out the “R” clip here, but you can see the top loop of the clip on the right.

For the drive crank, I drilled holes in the drive rods just large enough to be able to slip the axle through them, and threaded them on with a washer and small pipe-band-clamp on each side. The washers and pipe clamps keep the drive rods in the same spot on the crank, and insure that the drive rods don’t slip up the sides of the crank. It’s another case of “not pretty, but quite functional.”

P1020636

And here’s another questionable-quality video, this one showing the drive crank and pedals in action. Again, not all that smooth because I was trying to keep the camera steady with one hand. Also, both this video and the above steering video might give the impression that there’s a ton of friction in the two systems. They’re certainly not finely-tuned, but they really are pretty free and smooth.

This entry was posted on Monday, June 15th, 2009 at 9:57 pm and is filed under Pedal car. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

9 comments so far

Jason Fabbri
 1 

Great shots Mark. I wouldn’t beat yourself up too much on the steering, I think it’s a great solution. As for the aesthetics of it, you could always extend the front end a bit by making a “fake” radiator that hides the steering.

June 16th, 2009 at 8:45 am
Grampie
 2 

Nice presentation of the work. I can remember the carts we built when I was a kid and this is so far from that it’s scary. Very nice job that any youngster would be proud to pedal around.

June 18th, 2009 at 10:28 am
 3 

Hi Mark,
Looking forward to your latest pics on the car! I’m well under way and blogging my progress on the Bugatti. You can find it at http://thegokart.wordpress.com/.

Jason

August 23rd, 2009 at 7:31 pm
 4 

Hi Mark,
I just reached the point of getting the steering together on the Bugatti if you wanted to compare notes:
http://thegokart.wordpress.com/2009/08/29/chapter-eight-steering-down-the-road-of-life/

The tie rod ends you pointed me to sure worked out great. Any paint on the MG yet?

Jas

September 9th, 2009 at 8:49 am
SANJEEW
 5 

Great job
Please give a other steps

February 18th, 2010 at 8:42 pm
Doug
 6 

Looks great! Any plans or dimmensions?

December 8th, 2011 at 5:57 pm
Edward
 7 

Can you send the plans to my email so I can make one for myself xxgamer999@yahoo.com thanks if you can.

October 5th, 2012 at 3:09 pm
DamHy
 8 

Hi Mark !

I would like to know if it is possible to send me this plan with all measures ?
I’m sorry, I’m french, I don’t speak english very good but I think you do a good job ! I would like to do the same !

DamHy

May 12th, 2013 at 6:50 am
 9 

Hi Mark,
I just happened to be searching for plans for a pedal car based on the venerable MG TC and came upon your site, not sure if you still are active on it, if you are and can help me find a set of plans I would be most grateful.
I happen to own a real MGTC and was thinking of building a model for my grandson ( 3 years old ) in the hopes he may be interested in inheriting mine when the time comes !!
Will be very happy to hear from you and find out how your project ended up.

Kind regards,
Malcolm.
malcolm.stanton@sympatico.ca
East Garafraxa, Ontario, Canada.

January 17th, 2014 at 1:58 pm

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