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bgkast
bgkast UltraDork
1/16/15 2:09 p.m.

Pedal mount is finished. It seems to be plenty stiff, and is fairly light (and looks cool ).

More steering parts arrived yesterday: the upper bearing, lower bearing and a shaft collar.

Unfortunately despite the lower bearing package being marked 3/4 the bearing is actually a 7/8 bearing. A call to the vender this morning has the right one on the way, and they told me to keep the wrong one. Excellent customer service by Chrico vw and buggy parts. (Thanks for the suggestion JThw8) Anybody need a 7/8 bearing?

With the pedals mounted I started playing with steering wheel placement. I really need to mount the seat before I finalize the location, but for my initial tests it looks like the dash bar is right where I want the steering wheel to be. So far this is the best placement compromise without conflicting with anything. I'm debating keeping the extended shaft as a accident deterrent.

Dusterbd13
Dusterbd13 SuperDork
1/16/15 2:24 p.m.

Sharpen it to a spike and the rat rod guys will applaud your engineering.

turboswede
turboswede MegaDork
1/16/15 3:35 p.m.

or, since you're in Washington, you can turn it into a bong and tow a trailer with a grow operation to pay for the gas...

bgkast
bgkast UltraDork
1/16/15 8:15 p.m.

In reply to turboswede:

I don't think my arm os long enough to hold a lighter all the way at the bottom.

bgkast
bgkast UltraDork
1/23/15 7:33 p.m.

It takes a surprising amount of time to get the ergonomics of the cockpit sorted out. Over the past several days I have tried several positions for the steering wheel and seat. After much testing I found a comfortable fore/aft location and angle for the seat. I tried setting the seat both 1.5 and .75 inches off the floor and came up with the same location and angle, so it must be right. I am going with the lower position to give myself some additional head and helmet room. At the higher position my helmet would just hit the 1" SCCA required roll cage padding. Also for street driving without a helmet the more space between my skull and steel tubes the better!

I also found two comfortable positions for the steering wheel/shaft.

High (over the dash bar):

And low (under the dash bar):

I prefer the high location, because it gives more of a Z shape to the steering shaft to aid in safety. In the low position the shaft basically runs straight to the spline on the rack, and I'm conered that in an accident it would act as a spear pointing directly at my face.

I liberated the steering shaft and spline from the Neon's steering column. It just happens to be 0.75" ID, and the narrow part by the spine is 0.75 OD.

Last night I mocked up the "high" steering position in metal and found that the upper U-joint will conflict with the brake master cylinder.

In the photo the bolt/nut on the joint is hitting the fitting on the back of the cylinder, and the lower part of the shaft still needs to come up a bit to point in the correct direction, further increasing the conflict. I may need to go with the "low" steering shaft location. With the low configuration the angles are such that I could get away with only using one U-joint at the steering rack, but I think that using a single U-joint is a no-no due to the non-constant rotation that a U-joint transmits. Can anybody confirm or deny this?

NOHOME
NOHOME UltraDork
1/24/15 7:02 a.m.

If you look at an MGB, it uses a single U joint. However, alignment of the two shafts is critical and done with shims at the rack mount. While the tow shafts wont be in line, if you picture the mating shafts as having a point on the ends, the two points must meet head to head so that the angled rotation is transferred down this common centerline.

bgkast
bgkast UltraDork
1/24/15 5:30 p.m.

Thanks, I hadn't thought through it enough to consider the precise alignment that would be needed with a single joint. I have two joints already, and plenty of room to fit them, so no reason not to use two.

spandak
spandak New Reader
1/25/15 1:09 a.m.

You are correct regarding the use of one U joint. The rotation is non-constant and can cause some weird behavior, in theory. I drove an FSAE car not too long ago with one U joint and didnt notice anything odd about the steering. Data point of one. If you do go with two joints be sure to support the central shaft or there will be binding issues. With a single joint you might be able to get away with leaving the joint floating as long as the the opposite ends of both shafts are well supported.

I love these threads, I plan to start a project like this one day.

bgkast
bgkast UltraDork
1/26/15 3:53 p.m.

In reply to spandak:

Thanks, I wasn't sure how noticeable the non-constant rotation would be in the real world. I believe I can leave the intermediate shaft (between the rack and the main shaft off the steering wheel) un-supported if I only have a single joint at each end. If more than two joints are used (including using a "double joint") The shaft requires support.

More mock-up....I'm itching to get back to actually building something.

I figured out what it would take to get the upper steering position to work. The advantages to this position are slightly better leg clearance, probably better crash safety and more clearance where the steering shaft passes between the pedals. Disadvantages are still-tight clearance with the brake master cylinders/brake lines, harder to build, and the top of the steering wheel is higher than the cowl which might look weird.

Basically the back edge of the u-joint has to be over the dash bar. If I go this way the chrome bushing in the photo will be replaced with a flanged bushing inserted into a piece of tube that serves as a steering column. The steering column tube will be welded (or bolted?) to the dash tube and will have another similar bushing right behind the steering wheel.

I also did a more detailed mock-up of the lower position.

This would be easier to build, but there isn't much Z shape to the steering shafts, and there isn't room for the collapsible accordion in the intermediate shaft. It also gives less (but still adequate) clearance between the bottom of the wheel and my legs, and the shaft and my feet by the pedals.

I'm going to make the seat mounts and mull it over. Any input is appreciated.

Dusterbd13
Dusterbd13 SuperDork
1/26/15 4:25 p.m.

Would notching the dash bar help?

bgkast
bgkast UltraDork
1/26/15 4:28 p.m.

In reply to Dusterbd13:

It would help get the steering shaft either slightly higher or lower, depending on which mounting scheme we are talking about, but not enough to worry about, and not enough to justify the extra effort or loss of strength.

Mad_Ratel
Mad_Ratel Reader
1/27/15 6:02 a.m.

Is there a reason You cannot put it above the bar? oh steering wheel will be even higher over the cowl...

how did others solve this?

NOHOME
NOHOME UltraDork
1/27/15 6:41 a.m.

Can you not do something like what the hot-rodders do with the exhaust?

tuna55
tuna55 UltimaDork
1/27/15 7:18 a.m.

I'm with nohome. Build a circle out of the same diameter tubing and weld it in place on the dash bar and run your steering shaft through the middle.

rcutclif
rcutclif HalfDork
1/27/15 11:58 a.m.

Are you a left foot braker? if so (or if you want to be), I'd make real sure that the steering shaft isn't in the way of my foot moving between clutch and brake.

bgkast
bgkast UltraDork
1/27/15 1:11 p.m.

I'm not a left foot braker (yet) but in the low position the shaft will clear my size 11s by 1/2" or so. I don't want to compromise the sturcture of the dash tube (it's part of the roll cage afterall) by going through it, espically since it works for me to go over or under it.

I lied about moving on to building something and did......more steering mockup. This time a detailed mockup of the upper position.

It clears, but just barely!

I have about 1/8" clearance between the 3/4" steering shaft and the corner of the master cylinder. These master cylinders are no-longer made, so I checked similar designs from Wilwood ant Tilton, and they seem to be shorter in length so it doesn't look like I am designing myself into a corner. Now that I know that both positions will work, and be comfortable to use I need to think about things like cowl clearance and space for gauges...

bgkast
bgkast UltraDork
1/29/15 12:52 p.m.

Back to building!

I made up some seat mounts last night. I am happy with the design, it's elegantly simple and allows the seat to be moved if necessary.

I still need to add some "speed holes" and weld them into place. I will use a gusset on the rear where it mounts to the chassis to add stiffness.

I am thinking of making something like this for the seat back mount:

bgkast
bgkast UltraDork
1/30/15 10:36 a.m.

I had a scout meeting last night, and also had to make biscuits and gravy for a brunch potluck at work, so I only got a few minutes in the garage. I spent it drilling speed holes in one of the brackets. Turned out looking good.

Cool_Hand_Luke
Cool_Hand_Luke Reader
1/30/15 11:35 p.m.

You're involved in scouting? I just got my Eagle

bgkast
bgkast UltraDork
1/30/15 11:46 p.m.

I'm a Tiger den leader. They've got a way to go before Eagle.

Mad_Ratel
Mad_Ratel Reader
1/31/15 10:08 a.m.

wow, just made me count the years since I got my eagle... too many... :P

bgkast
bgkast UltraDork
2/2/15 12:31 p.m.

I managed to find some time after the big game to finish up the driver's seat mounts.

I narrowly avoided a 3rd degree burn after I grabbed a freshly-welded end of one of them with gloves with a hole in the finger... I let go when I saw smoke from my skin Ended up just charring my finger's callus a little. Those gloves are going in the trash!

I also mocked up the passenger seat. It is similar to the driver's seat, but is a 20-degree layback, verses the Driver's 10-degree layback. Both seat backs will be mounted at the same angle, and the lesser angle of the driver's seat will give some thigh support for pedal work, while the passenger seat will be almost flat on the floor. I tired it out and it's more comfortable than it sounds.

Fun fact: The passenger seat was originally used in my first 24 Hour of Lemons Fiero which met its demise when I spun it into a concrete wall trying to chase down a Miata at a Chumpcar race in Spokane. Hopefully the Midlana will have more of the the handling characteristics of the Miata, not the Fiero!

Here is a shot of the ill-fated Fiero being hauled home, and it's first start.

The head gaskets were a little shot on that engine. If you cranked it with the spark plugs out it would squirt water like a fountain!

Lonny
Lonny New Reader
2/2/15 7:46 p.m.

Your fabrication skills are great, I am looking forward to seeing a video of it driving.

The welds and mounting brackets in your pics look very trustworthy.

java230
java230
2/3/15 10:54 a.m.

Fantastic build!

A couple questions, are you on a 5k total budget, including the donor car?

And will you be trying to get it plated and titled in WA? I've been wanting to do a kit car for awhile, love to check yours out in person some time. The windshield is the part I can't decide if its required or not.

bgkast
bgkast UltraDork
2/9/15 7:07 p.m.

Passenger seat mount is done, and holes are drilled to mount the driver's seat. I hope to be sitting on a bolted in seat making engine noises tonight!

In reply to Java230:

I was shooting for a $5k budget, but may be a bit over with the shocks ($500 plus) and the axles ($500-800) still remaining to be purchased. Here is the windshield law for WA: http://apps.leg.wa.gov/rcw/default.aspx?cite=46.37.410

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