I have a feeling if I tighten it down so its tight tight I wont be able to move it fore/aft much easily. What about a bearing at each end of a piece of 3/8 steel?
eh? it has an extended inner race so its not pressing on both surfaces of the bearing, plus a shoulder on one side so it doesnt slide out of the bar http://www.mcmaster.com/#57155k338/=2kqbgu
I would make four parts, with holes on the non bearing ends to bolt them together (for adjustability).
I’m not really sure why you still want to use the flatbar and screw around for hours trying to make something when you can buy exactly what you need for $50. You don’t want a flanged roller bearing at the ends of your flatbar. I think you’re confusing the term “bearing area” with a “roller bearing.” Bearing area refers to the area of the rod end or flatbar where the force is applied. If you don’t have enough bearing area (area where load is applied) or the tolerance is not tight enough you will have TONS of loading on the extreme edges of the bearing area. What this means to you is that after short time, the holes will “egg” out - turn into ovals and leave you with a ton of slop. The force from one shifter is transmitted into the tie rod to the other shifter by the bolts holding the rods to the shifter via the inside of the hole in the tie rod end - NOT THE FACE OF THE FLATBAR OR ROD END!!! You CAN NOT crank the bolts down tight that hold the tie rods to the shifters. Tighten 'til snug and use nylocs or a nut and jamnut. Yes, there will be some metal to metal contact of the faces of the rod ends with the shifters. Insert a washer in this area. Steel will work fine, or better would be something like oilite or bronze. It has a lower coefficient of friction and be less likely to gall. Don’t use something with compliance like plastic. The other issue I see with 4 chunks of 3/8" flatbar is that it’s going to be damn heavy and result in a really crappy shifter “feel”. It’s going to feel really heavy and damp like you’re shifting a dumptruck instead of a car. Don’t forget too that you have to drill the holes in the ends of the flatbar for an interference fit with a bushing. We’re talking just a few thousandths of an inch here. Also, the idea you have for adjustability will work only if executed properly. Ideally, you’d want to stagger all the holes in a zigzag pattern so you can space them closer together for finer adjustability. Chances are you still won’t be able to get the shifter exactly where you want. Furthermore, all the pieces you make need to be exactly identical. The upper and lower “tie rods” you make need to be exactly the same length. If you use the “official” rod ends and threaded rod you have infinite adjustability, something to seriously consider. Another problem you have with your drawing is that the “adjustment holes” are tiny. I’m assuming you’re planning on putting bolts in these holes. They will be under both tension and shear loads so you need something with some bulk to it.
Another problem you have with your drawing
the drawings are using paint and are just to convey an idea, nothing more.
The force from one shifter is transmitted into the tie rod to the other shifter by the bolts holding the rods to the shifter via the inside of the hole in the tie rod end - NOT THE FACE OF THE FLATBAR OR ROD END!!!
thats why I chose the bearing with the extended inner race. plus those bearings are only 1/2" in diameter…
I am not trying to be a dick or anything but I cant just close my eyes and say ‘ok’, I need to fully understand and believe what one is saying first. One of my many character flaws I guess…
insert white flag waving
My main problem with those rods is that I dont think they will transmit the left to right forces well. But I guess if I can lock the two halves together they will act as one unit… I need to figure out my length so I can see if I can do a left handed thread on one end, a right handed thread on the other, with a threaded rod in the middle.
what about the vertical members? if I use 3/16 hardware, whats the thickness I should use for the square stock? whats the strongest way to attach something to the original shifter? and vice versa for the ‘new’ shifter to the other end?
The rods will transmit the left to right forces just fine. They do it via torsion, so long as you have the threads locknutted. I know what you’re thinking with the flat bar-it’s a big heavy piece of metal that can’t not transmit the force.
The right/left hand thread idea works well as long as you use male threaded rod ends and can machine a sleeve to go in between the ends. Do you have left hand taps? If you don’t, it’s not a big deal. In that case, buy all female rod ends and just use threaded rod to go between. If you need to adjust, you have to unbolt the rod end, rotate, rebolt. Not a big deal, just takes a few extra seconds.
I’m not sure what you’re asking about for the vertical members. I’m assuming you mean the “new” shifter lever? 1" square tubing with a .093" wall should be fine. With the original shifter you have 2 options, drill holes in it, or cut it off and weld the 1" square tubing to it. When you drill the holes in each of the vertical members they have to be exactly the same distance apart and the exact same distance from the fulcrum of the shifter. Don’t mess it up or you will put the system into bind.
What exactly are you planning on using 3/16" hardware for?
For attaching the rods to the shifters, 5/16" is going to be plenty big enough. You could probably get away with 1/4". Use good grade 8 hardware, not the cheapest stuff you can find.
wow sorry. I meant 3/8", not 3/16. lol I meant for the hardware that will attach the rod ends to the vertical pieces. I do not have left handed taps, but some of the parts from McMaster can come in left handed versions.
A butt weld between the stock shifter and a 1x1" plate (for the bottom of the 1" square tubing) will be sufficient to transmit the forces and not bend/break? should I drill a hole in the 1x1 piece, weld it top and bottom to the shifter, then weld the square tubing onto that?
And I figured the dimensions would need to be the same in regards to fulcrum and pivot points, but thanks for confirming that.
I noticed a machine shop on my way to work, ill get them to drill the holes in the vertical pieces. should I get brass spacer/sleeve (http://www.mcmaster.com/#spacers-and-standoffs/=2l35y4) to press into each hole? or just something in the rod end? or just see how long it lasts with just the bolts and rod ends…
Now that I’ve thought about it for a minute, square tubing is the wrong answer. You want to use solid stock to give the bolt a lot of bearing area. Or, weld a sleeve through the square tubing for the bolt to pass through. Press fitting a bushing through the tubing is a poor choice since there is little area of interference to hold the bushing in place. You need a close tolerance for the holes through the shifters. Alternatively, you could drill and tap the holes through the shifters. This way, you use a bolt that passes through the rod end then into the shift lever. It will need to pass all the way through the lever so you can lock nut the other end of it otherwise it will just want to fall out. This route saves you from having to drill a precise diameter hole.
I’m confused as to juat you’re asking about welding the shifter, try to clarify.
Don’t forget - if you use female rod ends, one right one left hand thread, the threaded rod in between them needs to have opposite threads on opposite ends. So you need a left hand tap or die either way
I was going with what you said about the square tubing, I would have needed something to weld the rod to. I was thinking solid stock the whole time, but was going with as I was told. lol.
I was also thinking about taping the holes for the exact reason you stated, good idea with the lock nut on the other side though.
with the rod ends, McMaster makes left handed rods ends and threaded rods. it really depends on the distance needed what I will do with that. I can report back tomorrow with that.
solid 1x for the vertical pieces? what if I drill and tap the ends of the verticals to screw to the respective shifters, how much penetration do I need, 1"?
Drilling and tapping the ends of the solid stock in not a good idea. You’ll have no way to properly index the stock on top of the tranny or lock it from wanting to rotate. Welder is your friend.
what do you mean by properly index? and if I thread the rod I can put a nut to lock it against the stock.
If its decided that I should weld it I think I should drill into the stock and weld (so the shifter coming out of the tranny goes into the stock a little), i dont like the idea of a butt weld in that situation. And if I weld it its basically permanent, i cant take it apart to change anything down the road.
Alright. update. I might only have to go vertical with the shifter, as in moving the fulcrum UP. i’ll have to double check this weekend. I bought the center console I want to use so Ill know for sure.
If building it yourself is too much, you may want to buy and modify a Subaru shifter assembly:
It’s a single rod design with fairly tight bushings instead of bearings. The bottom bar in this picture is meant to just hold the cup for the ball (bottom pivot). This pictures is for an STi, which has the additional cable for the reverse lockout, the WRX and base Impreza shifters do not have this.
Yea that looks pretty sweet. ill have to get more dimensions this weekend to see what exactly I have to do.
I love all this engineering discussion. lol