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Post by pceng on Mar 13, 2012 18:08:13 GMT -7
Did this 40 somthing years ago, and for some reason thought of it not long ago. Took about a month of tinkering to get consistent results. Wanted something that would stand up and go. But with all the magnet and armature and tire and wheel switching. I'm happy with the 30-40 inches it goes on 2 wheels. Though, since I've stopped with it I keep thinking of years past. The Hemi Under Glass, Little Red Wagon, I gotta get back to it and make a car do a full 1/4 on 2 wheels. Could be the voltage, don't remember what those old metal transformers were. But I wanted this to work at 13v's. So that's what I've got right now at 13v is a 30-40 inch wheelie. Tried it on 22v and car just jumps off track. But, I ended up with a pretty fast t-jet. Started off as one of two cars built for bracket racing. And ended up back where it started except for tires. The arm is a 12 degree advanced 4.4 ohm balanced, polished. Got it from Sgrig (tjetsgrig - does great work, if you haven't tried it out). Magnets are poly.
In case you haven't done this it is an easy set-up, But tweaking is needed to get thing right. Take pick-ups and springs off chassis. Cut pick-up shoes just past front bend, will end up with a piece that looks like a U. Lay a 3" piece of electric tape across chassis, sticky side up. Place shoes in place on chassis and lay on tape. Should be just behind bend in pick-up. Next place guide pin on tape (center, and reverse pin from normal so pin is on leading edge. Fold over tape ( I started with tape edge even with shoe so one fold of tape over bottem lift and fold again). Probably there is something better than tape. If anyone knows of something please let me know. Pick-up springs are stretched and a drop of super glue goes in hole then stretched spring. After glue dries (thirty seconds or so depending on glue). Hook shoes back on hangers your done. But now comes the tweaking. If this is your first time hang in there, its worth it when you see it work. If you've done this let me know what worked for you. I'm all ways trying to learn some thing. Maybe we could have a wheelie competition, or demonstration.
I don't think I mentioned that tape is about 1/4" wide (cut wider down). And guide pin needs to be alittle longer than stock. First used the old red pin for rear. Last batch of pins I got from Lucky Bobs. He has some that are more durable and longer then stock.
Good luck if you try this. Let me know if I can help. If any one else has had luck with this, please any tips will be gladly recieved.
tia..............PC
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Post by bondoman2k on Mar 13, 2012 23:17:38 GMT -7
Hey PC, I haven't tried this yet on an HO car, but I did a Little Red Wagon in 1/24th that went the entire length of the track, 55 feet, on the rear wheels at 1.3's. What you might try, and not sure how well this works with HO, is some weight in the rearmost part of the car. That's what I did on the 1/24th. Also, I needed to ad weight at the guide flag (or the pickup shoes on HO cars) to keep it from 'deslotting'.  Actually, would be GREAT if we could do what some of the real 1 to 1 guys did on the 'early' wheelie cars. Had 'tubes' on the frame rail areas of the cars/trucks that had large ball bearings in them. When the car sat at the line, weight would be in front. As they accelerated, the weight (ball bearings) moved to the rear, and once they were in full 'wheelie mode' ALL the weight stayed in the rear. Really wonder if this could be done in our scale and if it would work! ;D (or at least I HEARD they did this, never actually saw it on any of the cars/trucks..lol) Ron (Bondo)  |
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Post by TGM2054 on Mar 14, 2012 11:04:41 GMT -7
I've been thinking about doing that. I've already got a chassis lined up, started working on it over a year ago but lost intrest till now. I've got a Little Red Wagon body coming so maybe it's time to get back at it.
Ron's got the right idea, a little weight behind the back axle would probably help a lot. you might try getting some of the tungsten weight they use in pine wood derby cars. They make a putty version, that would be, or will be the one I try.
One other thing to try is a different rear end gear. Different crown or pinion to lower the gear ratio.
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Post by pceng on Mar 14, 2012 12:13:41 GMT -7
Hey Ron, long time hope all is well. Intresting about the tubes. Originally did not want to use added weight. But have been thinking about it. Might have to make a second one with weighting. Never new about the tubes and weight shifting. Been thinking about this since reading your post. First thought of brass tubing under plate clips, but don't know if they would hold enough weight. Use to use this type set-up for putting lights in cars for night racing. Been trying to think of something larger and maybe a small flat container like used to hold lead for mechanical pencils could be fitted above plate. I did add weight to pick-ups helped to keep things consistent. Solder on backside of shoe (contact area). Did this because one shoe would lift more than the other. Maybe I should have said drop instead of lift. I could have messed with springs to even things up but solder just seemed easier. Had allways thought that being rear engined was what did it for those early cars. But thinking about them, I remember they would lift and then kind of sit back. Weight shifting would definatly account for that. Now when I start getting complaints abouit the track running down the hall I'm blaming it on you! ...lol... Right now I have four pieces of track for testing. But if it's going to go a full 1/4 I just gotta see it. Yep, think you started something Ron. If you've never done this in HO give it a shot. Can be very frustrating at times (but weight would change that), and extremly gratifying when working. Alot of the results while testing were funny to see. First time on track was 22v's and car just flipped over backwards. That started the arm switching but once I realized what the voltage was DUH! (one of those moments). This will work with almost any arm, had 14 and 15 ohm arms working at 22v's, but at 13v they would not stay up. Just kinda up down go. I'm not sure if it was the voltage because later I found the idler gear I was switching from plate to plate had afew bad teeth. Off to look for one of those lead containers. Time to start on a wheel STAND car. Thanks for the info Ron!
...........Peter
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Post by pceng on Mar 14, 2012 12:26:33 GMT -7
Hey Tom, just caught your post. If your thinking about it, do it buddy. It's worth the laughs. Have to admit car sits next to track and every time I do any testing on something it makes afew passes just for the grins.
............Peter
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Post by ninjatek on Mar 14, 2012 12:46:09 GMT -7
I also have a LRW body I obtained a few months ago. I have not done anything with it yet, just a lot of thinking. Tape idea sounds quick and simple. Just for the sake of discussion, how would a wheel stand competition be judged? First distance, then speed? Extra points if bumper sparks are produced? First car to deslot, make several spins on it's rooftop, then roll on it's side and stop as if break dancing?  |
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Post by TGM2054 on Mar 14, 2012 17:09:53 GMT -7
I'd think distance, but the crash and break dance thing could work also!  |
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Post by pceng on Mar 15, 2012 9:29:13 GMT -7
If it ever comes to a competition my vote goes for distance. This with no weighting allowed. Seems it would be very easy to get full 1/4's with weights. But we could still have a best dancer award. The word crash just makes me cringe. Cordell, the tape is the quickest way I know of to make p/u's into a swing arm. Though years ago I did see someone was making a p/u assembly with molded plastic instead of tape, and the shortened shoes. Have no idea if it's still done. I did use a couple of drops of super glue on the tape to try to stiffen it up. Been thinking of maybe a strip of thin plastic inside of tape. Funny you mentioned the sparks, I've been trying to come up with a set up where the flint and striker from disposable lighter could be used in rear. Did not want to use anything that would mess with track rails.
........Peter
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Post by bondoman2k on Mar 15, 2012 20:18:54 GMT -7
I would have to agree, gotta be judged on distance. I personally wouldn't want a nice 'pretty' looking car torn up, as well as any other 'collateral' damage that may come from crashing. I do have to disagree with one thing tho. I really don't think there is any way the cars will go the full distance of a track without weight. The problem is that as the speed and momentum pickup as it goes further down the track, the vehicle will eventually 'catch up' with itself, this dropping the front. I think there should be a maximum weight limit tho, since it would be VERY easy to just load it down with weight and make it work, since a time or speed wouldn't matter if it's only judged on distance. If we do judge it on distance, then the weight might not actually matter as far as the judging, if everyone is competing under the same rules. But if you want to go the most distance you can, on the rear wheels only, you HAVE to figure out a way to keep it in the air. Actually, you would be trying to fight 'centrifical force' (or something like that..lol..I'm no engineer so I don't know the technical term) in order to keep it up without the weight. Ron (Bondo) |
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Post by ninjatek on Mar 16, 2012 8:24:53 GMT -7
I also do not think a wheelie can be maintained for the entire 1/4 without the assistance
of weights (or some other mechanical assist, ie. springs, rubber band, etc.). A full quarter
mile wheelie is probably best for exhibition purposes, unless you want to throw in speed
as a factor of judgement. If not, in a field of eight, six guys do full quarter mlie wheelies,
who wins? In a competition, although a wheelstand is the visual result, the actual judge-
ment is of the power or torque developed. So pceng's 30"- 40" wheelstand without any
added assist sounds quite impressive. I think no added weight or set a maximum added
limit would be the way to go. At a minimum the body should return to start position upon
coming to rest. Nothing could be stranger looking than a stopped car resting on it's bumper
defying gavity. Which may occur if excess weight is used in a weight shifting system.
Other things I have been thinking about. What qualifies as a wheelstand? Getting the
body at a 35 degree angle? 20 degrees? 5 degrees, you can almost attain this just by
streching the pick-up springs. When is the wheelstand considered complete?
Just thinking out loud.
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Post by pceng on Mar 18, 2012 13:29:31 GMT -7
Hey guys, some of the points made have changed my mind. First I thought distance was the way to go. But this would be very hard to be accurate with. The angle of body would also be real hard to be accurate about. And yea, stretching the springs to much will keep the front end off the ground (put together second chassis and have this problem, not stretched as much as first try, must be stiffer). I think the car should sit in a normal position (before and after wheelie), and be judged on speed, distance, and angle. A combination of these judged by hosting track, to determine "best" wheelie. From the car I built, I know it's hard to see exactly what's happening. Maybe the arm and mags I used, but it's up and down fast. Could be my eyes but realizing what just happend hits home when the front end of the car comes back down. Easiest part for me to see. The track is 15" pcs. so I just kinda pick out about where it came down to judge distance. Should say about where because this is hard, try to judge it by thirds of the track or half just to get idea of something close. These things lead me to believe that a competition would be best if just judged on decided criteria and not just distance. I know I'd hate to be the one to decide which of two cars went a fraction further if they were close unless deffinate about results.
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Post by pceng on Mar 24, 2012 7:35:51 GMT -7
Been tinkering on stuff since Cordell, mentioned angles. The only thing I could think of was to extend the pick-ups. With the stock pick-up lenght a point is reached where the shoes will lift from the track. The car I have working has wheelie bars(functional) mounted just behind and about the height of rear bumper. This to keep the pick-ups on the track or keep them from leaving the same. Also the lenght of the body will play into the maximum attainable height of wheelie. Thought that if I readjusted the wheelie bars car might go higher, but pick-ups leave track. So the height of the wheelie quickly became an issue for just the second chassis. The pick-ups were straightend instead of being cut (squeezed with flat jaw pliers). Made the contact area on shoe twice as long (close to). Soldered braid onto front part of contact area, coverd hole left where normally hooked on chassis. Now the problem is intermitent spark, don't know how else to say it. Like its being switched on and off. Thinking that springs now are not strong enough for longer shoe. Used piece of plastic super glued to top of shoes this time and moved it forward to where normal contact area of shoe is (braids were kept short for this reason). Had to adjust position of guide to keep it in track with longer pick-ups. Just an update in case it might help, back to the tinkering.
........PC
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Post by pceng on Mar 25, 2012 9:08:15 GMT -7
Quick note - went back to tape, plastic to rigid. Adjustment of shoes very hard with plastic, tape allows flexibility in movment.
.......PC
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