Adventures of trike repairman

[C-Bag]

My SO and I own and ride tadpole trikes http://www.homemadetools.net/forum/t...8412#post53569 Hers is a Terra Trike with a front end that doesn't have sealed bearings on it like my ICE. It has brass bushings pressed into the steering knuckle. I'd been having a hard time getting the disk brakes to work properly without dragging. I noticed it had a lot of slop in the bushings and it finally decided it was time to tear into it. I also suspected that's why it didn't roll as freely as mine too as there was no way to do an accurate alignment. Here it is without the pivot pin.

After making the first bushing I realized the steering knuckle was not round so had to make the rest with a .003 press fit to make sure it was going not come lose ever again. I also left them .030 thicker to give a nicer fit in the frame. I put the bushings in the freezer for 20min and a little synthetic grease on the knuckle and pressed the bushings home. The knuckle pins are 12mm I guess as they were .470 and the closest reamer I had was 15/32 .468. Ended up filing down the pins to .467 as I couldn't wait for the adjustable reamer I ordered to show up. Now it was time to get a nice fit in the frame. I tried to think how to approach taking the .025 or so off the upper bushing, and thought WWOD? (what would Olderdan do? and decided to make an arbor for the lathe. One end is .467 for the knuckle and the other .5 to go in the tail chuck. I had a 1" worn out mill I'd inherited with my mill/drill and put it on the sharpener and put 3deg angle of cut on it with no 1deg dish so it wouldn't bite into the brass(hopefully). I also remembered what TM51 said about not chucking up the mill directly in the 3 jaw chuck and got out the arbor I also inherited with the mill/drill and mounted the mill in it and off I went.

I was able to fit each knuckle and install the pin and tighten it till everything moved freely with little or no slop.

For the first time I'm able to adjust the brakes properly and the alignment seems dead on. I've not gotten a side by side rolling test with the two trikes on a hill yet as that will be the true test. In the past if we started out even coasting mine would just pull away.

I also replaced the wheel bearings while in there and that proved to be an adventure too as they didn't see fit to provide reliefs in the bearing spacer to get a bite on the bearing to drive them out with. Along with a very finiky fit to make the bearings fit in the hubs with the spacer and then be tightened on the spindle.

[Frank S]

Nice use of an arbor to hold the knuckle in the tail stock much faster than having to make set up to mount on your mill table

[C-Bag]

Thanks Frank.

I've got a LOT to learn and when I realized I'd not thought the whole process through as throughly as I should have I started spinning. Just like you said, trying to figure out how I was going to mount that spindle in the mill securely was making my noob head hurt. I meant it as a joke partially but Olderdan's all lathe solutions for stuff is pretty inspiring. So when I remembered the old 1" mill and the arbor to mount it in the lathe, the arbor was the logical solution.

[PJs]

Terrific build C-Bag! I love the way you thought with the "Ways of Olderdan"! Excellent "spherical thinking" as Frank puts it on the regrind of the mill to the application, with TM's tip on mills in 3 jaws. Too bad your reamer didn't get there on time but you pushed through in style, imho!

There is a lot to be said about that creativity of building something better than it was before (with a bit of inspiration of others), making tools to make the parts, etc. that takes a project/product/thing to that next level of quality...Lights My Candle! Collectively eclectic consortium!

Great build C-Bag. If she beats you are you going to do yours too...with tapered rollers?

~PJ

[Frank S]

Being 100% autodidact when it comes to just about any machinist work. My methods of using lathes, Mills, bandsaws and just about any other machine you can think of would make most trained machinists cringe, but having done it my way for neigh on 50 years and still have both eyes and all digits of my fingers and have never broken or damaged a machine I guess it would be a little late in life to go to school and change LOL

[C-Bag]

The biggest eye opener for me is the creative attitude to machining on display here at HMT. As long as it's safe it's ok. I always thought being a machinist was a little more confining with strict ways to do things. But seeing some of the behind the scenes where folks who have been doing it for decades like FrankS, Olderdan, Paul, PJ and TM51 to name a few have given me the insight there's a lot more creativity involved than strict procedures.

I thought when I got my lo buck 9x20 & RF-30 it was just to make simple parts. But the ability to make more precision tools to accomplish things I could have only dreamt of doing before is an ever evolving revelation. Its also a lot like my mech work in that once you have the basics it's all about the old hand tips. Those are the kinds of things that you'd pick up working with some experienced guy in a shop. So these little tips that surface at the end of threads are the cool stuff for me, like TM51's using a small ball mill to start a angled hole, just to name a recent one, whoda thunk!

[Frank S]

C-bag strict procedures have their place many of us have over the years developed our own as well as use those found in books like the Colvin & Stanley American machinist handbook. And the ever present Bible the Machinery Handbook
I think that when I was first attempting to teach my self some basics my 4th addition of the American Machinist and the 14th addition of the Machinery's handbook were probably the most valuable tools in my kit at the time. Later when I was in High school I managed to talk a librarian out of an old dog eared Smoleys combined tables, I thought I was ready to set the world on end at the tender age of 16. I had been working at the Blacksmith shop for 5 years I owned a lathe a welding machine and had 3 books and a slide rule what more could a young man need? Possibly let myself get talked into Joining the Army @17? YEP.

[Toolmaker51]

C-bag strict procedures have their place many of us have over the years developed our own as well as use those found in books like the Colvin & Stanley American machinist handbook. And the ever present Bible the Machinery Handbook

Correct. I still have and treasure my original Machinery's Handbook[s]. They change over the years to remain topical, of course, or they wouldn't sell continually.
Once I was aware of Colvin's, Mark's Std Engineering, and the others, especially printed by machinery manufacturers [DoAll, Warner & Swazey, and yes even Bridgeport], began pursuit of those as well.
Strict conventions support things like interchangeability, as results, lesser so than the means. Like the internet and personal computing, they can't respond to innovation instantaneously, which in consideration isn't so bad.
Once it makes it into Machinery Handbook, its gospel. Solid, repeatable and extends as far as the reader base. Not unlike HMT.net at it's level; 15,000 some-odd deep.
And to C-Bag's whoda thunk, I repeat. Regardless the level of involvement, this is far more than just a hobby. Matters not whether you produce income or satisfaction. Perhaps those who do so for satisfaction are the real practitioners.

[C-Bag]

And to C-Bag's whoda thunk, I repeat. Regardless the level of involvement, this is far more than just a hobby. Matters not whether you produce income or satisfaction. Perhaps those who do so for satisfaction are the real practitioners.

With the cost and complication of recumbent trikes, they never get as affordable as two wheels. So I would have thought the quality of such a front end would have been higher too. But I was surprised to find the lower bushings in both knuckles floating loose and the uppers just barely tight. And the diameters of knuckle races different and like I mentioned .002 out of round. While probably not unsafe it made accurate alignment and surprisingly, brake adjustment impossible.

I don't know of any bike shops around here that have even a cheap lathe and mill so this truly turned into a labor of satisfaction. Obviously I was going to be deeply disappointed if I did all this precision engineering of fitting each of the 4 bushings individually for a .003 press fit, then making a .0015 king pin fit to the bushings. Then fitting the knuckles to the frames. Luckily it was worth it.

I've never gotten to check a new one of these models much less another used one so I have no idea if this is standard to the maker. For all I know they set it up to have this much play so it would steer freely, or more than likely was like where I used to work. Where the poor guy in the machine shop was working with worn out equipment and was over worked and underpaid. The person who did the assembly was just getting paid to crank out units and liked the fact he didn't have to go over to the press(who knows if they had one out in assembly, we didn't) to put the bushings in the knuckle with his fingers and they called it good. Too bad as alignment makes a huge difference in the feel of these things and having a loose front end bombing down a hill on dirt was a scary proposition before. Not now according to my fearless SO.

Still not gotten a chance to do the "downhill dyno" (good one TM51) but I've gotten no squawks from the pilot as she uses the trike to walk the dog. She reports having good brakes and smooth control as scares the locals and their dogs as she flys past feeling like a kid

[Toolmaker51]

C-Bags downhill dynanometer may have a result inducing fault. We ride two wheelers and I lose the downhill test consistently. I credit a pair of aerodynamic fairings carried by the distaff side, much to her disdain.
Or mountain bike vs tour bike with 90psi tires...