Custom Spacer & centering jig

jumbosrule

Fully FX Invested
Premium
Location
Redondo Beach, CA
Car
2003 FX35T
Name
Brad
Just something I have been working on. The spacers available for the FX are either 5mm and use the hub to center the wheel, or are 15mm and have a machined lip in the spacer (to extend/replace the OEM hub lip). I'm trying to stay away from using the spacer to center the wheel.

I wanted the minimum spacer required to clear my Stoptech brake calipers, which would be right at 7mm thick. I came up with a centering jig that can be removed after the bolts are all torqued down. I just drew this out in PowerPoint, so if anybody has any design ideas or improvements - I'm open.

At first I thought I would attach the jig so that it and the spacer are permanently attached to the hub (until you remove them). My reasoning was that the weight of the wheel will sit on the jig, and after the lugs are tightened down, the lugs and the hub take the load.

But for now, I am thinking to remove the jig. As long as the wheel is centered when the lugs are torqued, the jig won't be taking any load. I think. So it can come out. The jig is the small stepped cylinder. The first page is just to get the dimensions worked out. The second page is assembly. Black is OEM components and blue is the jig and spacer.

View attachment 171399



View attachment 171400

This way, the wheel will sit on the jig while you thread the lugs. Once tightened down, the wheel SHOULD be centered, so the jig can slide out.

If there is still a load on the jig after the lugs are torqued, then maybe we can come up with a way of fastening it to the OEM hub - maybe using the axle threads, or using set screws or something.

Comments welcome. Also - if somebody knows a place to have these jigs made cheap - I wouldn't mind a little collaboration in figuring out something that works elegantly.
 
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66.2 is the Center bore - and the outside diameter of the jig - so it slides inside the hub ring, and sticks out exactly as far as the hub lip did, prior to the spacer. That 71mm measurement would be the outside diameter of the hub ring (or whatever it should be exactly) so that the stock wheel fits exactly as before. My dimensions might be off - please correct me if you see something wrong.

The intent was to have the jig be an extension of the hub ring, telescoping out of the hub the same distance as the spacer.

If the stock wheel is 66.2, then that should really be the outer measurement of the jig, stepped down smaller to fit into the hub ring. I have corrected the drawing above - now it should be right.
 
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yeah, but the 66.1 (66.2) IS the outer dimension of the hub, that's the inner dimmension of the wheel bore, not the inner hub bore... haven't looked at my hubs but are they even center bored enough for this?

---------- Post added at 05:15 PM ---------- Previous post was at 05:07 PM ----------

now that that's straightening out, another thing I can add. you keep saying that with a 5mm spacer the hub is still able to center the wheel. are you sure? I don't think the actual pentration on the stock setup is more than 5mm... you have to account for the camfered edge which takes several mm's before there is even engagement...
if you look at the actual mark on the center bore of the rims & measure the actual hub contact mark I don't think it is much more than 5mm if that...
 
Ok, so then my dimension corrections should be good.

I got the idea while I was installing the BBK this past weekend. Could be the hubs are not high enough tolerance to do this, but I thought they looked like they could accept something like this.

Yes, good catch about the 5mm. Currently I have a 0.20" spacer and the hub just barely penetrates (even through the chamfer). Guess you would have to have a 4mm or less to still use the hub for centering. Using this jig would allow you to reference off the center bore of the hub to center the wheel. Using a spacer that comes with a machined lip, the lip is referenced off the spacer - which leaves a little room for error, though not much.
 
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I don't think the centers of the hubs are machined to high tolerances at all, just the outer mounting lip, don't think this can work really...

check the stock engagement marks on the wheel to see if it is much more than 5mm, don't think it is
 
There's gotta be a way to know for sure! I'm happy to try it out just to see where I get hung up. Just need to have these things made so I can start playing around.

There is a chance I could grab the outside of the hub ring and then step down to the bore diameter. The wheel bore with chamfer might give me enough clearance for a shoulder on the hub ring. I'd probably have to take the jig back a bit further, like a sleeve over the hub ring.

---------- Post added at 04:50 PM ---------- Previous post was at 04:46 PM ----------

Hey Jumbo, what is your profession?

I'm a mechanical engineer for Boeing, contracted to NASA. I work on Space Shuttle Cargo Integration Hardware - all original design hardware to connect mission payloads to the space shuttle itself. This includes electrical and mechanical design. I'm a project manager, so I submit a proposal for the project, then maintain responsibility for technical, schedule and cost. Requirements development, hardware design, analysis, subcontract purchasing, fabrication testing and certification before delivery to NASA. Been doing it for 14 years, since I graduated from Tufts up in Boston.
 
that is what the available 10mm spacers do, center on the outer & step down.

personally I think your putting too much effort into trying to reinvent the wheel to just save 3mm space. making those yourself are probably going to cost more than just buying an of the shelf 10mm spacer. also realize that there is going to be some point that the wheel is going to sit at the hub level & there is no room for the step down, at 10mm the step down is very minimal connection between the new surface & the old...

if you really want to design & have these built, one option is emachineshop.com I used them to make my custom balljoint adaptors, but there not cheap at all & to bring cost's into the relm of reasonable will require multiple quantities...
 
Ok ya, I thought I remembered you saying that. I can tell you're smart because I didn't understand 90% of what you said technical-wise. :laugh: I'm majoring in ME coming up this fall, so maybe one day I can understand some of that.
 
Ok ya, I thought I remembered you saying that. I can tell you're smart because I didn't understand 90% of what you said technical-wise. :laugh: I'm majoring in ME coming up this fall, so maybe one day I can understand some of that.


LOL - Man - and I thought I was using car speak! When I start talking about my car at work, eyes start to glaze over. I've learned to air it out on IS. Guess I still need to work on my technical communication...
 
now that I think about it, I didn't play with 10mm spacers, it was 15mm... I remember thinking at the time I couldn't figure out how they would deal with like a 10mm, there may still not be enough room for the step down...
 
I tried to read up on all the spacer threads. Basically I learned you can bolt up at a 25mm spacer. 20 and 15mm require the OEM studs to be shortened. I think Ege is the spacer dude on the scene - I think he's been through a few sets.

I just took a look at the hub and I think you might be right about the bore - it's not a tight tolerance. There is, however a smaller bore inside that looks to be pretty smooth. Not sure.

The whole point of this jig is to allow the centering of the wheel when using a universal spacer that can't do that. Doesn't matter to me if it stays in or comes out after the lugs are torqued. I was thinking way beyond an FX application, though I'd like to prove it out on my car before trying to get some made. Anybody who uses a universal spacer might be interested in something like this if (like you said) the price comes down enough.

Since it's just a stepped tube at this point - that's simple lathe work. Wouldn't take long to chug out a run out of bar stock.
 
And there it is. A universal spacer based on stud pattern with an interchangeable centering hub ring.

View attachment 171401

I guess that would have been the eventual design. The difference is - I don't see less than 10mm spacers for Kics? Not that most people would want or need that.

If there is one thing that I have learned about design - somebody else already thought of it. Most of the time, 100 years ago.
 
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I tried to read up on all the spacer threads. Basically I learned you can bolt up at a 25mm spacer. 20 and 15mm require the OEM studs to be shortened. I think Ege is the spacer dude on the scene - I think he's been through a few sets.
.

I've been through 3 Ichiba sets but the requirement to cut studs depend on the spacer type. My first two were Ichiba V2, which have 5 studs already pressed into the spacer. You slide this onto your studs, tighten them and then tighten the wheel to the other 5 studs. Here's a pic:
15mmstudstr2.jpg


These will require 25mm or more thickness OR cut studs for anything thinner than that with OEM wheels because the grooves at the back of the stockers are not deep enough and the extruded additional 5 studs touch the wheel.

The Ichiba V1 spacers are the regular spacers that you'll see everywhere. They are like the pic below and they require your stock studs to be replaced by longer ones. V2 doesn't require that
IchibaSpacer.jpg

Now the play between spacer-hub ring OR hub ring-hub OR hub ring-wheel are very minimal, 1mm at most. Still, you can turn it on its axis which means there is play and it comes out as vibration after 80-90mph. Initially, I tried Turbo's method of electrical tape around the hub etc but then the ring wouldn't fit anywhere, it was such a small amount of play.. Eventually, I used some teflon tape around the hub, between ring and the spacer and between the ring and my wheels. That worked very well for about a month or so but I think the teflon tape wore out so I need to take it out and use some electrical tape with some WD40 to slide it in..

I would like to see a spacer with the hub centric ring integrated/machined but still you'll have that minimal amount of play between the hub-spacer and/or spacer-wheel unless you find a way to install the spacer so that it'll tighten around the hub and stay there perfectly centered.

IMO, getting 10mm project kicks, Ichiba or H&R spacers would be the easiest way. You won't even notice the extra 3mm. Additionally, you can easily go out of your way to come up with the best method of keeping it centered :smile:
 
I think the best way, if your really determined to do it the best way & really get what you want would be to bore the rims out to like 71mm, then you could make an adaptor from the 66 to the 71 & do any space your heart desires... but again, probably a lot more $$$ than an off the shelf solution, unless you know a machine shop thats cool with you... I have a friend & he used to buy the 7 series wheels & rebore them to fit the 5's... didn't seem like too big of a deal to get them done...

my wheels are 71mm center bore & I need to use hubcentric rings to center them... if I ever wanted to space mine that's exactly what I would do, replace the hubcentric ring with an adapter & space with extended studs... foolproof.

the ones rookie showed look cool, I like that they specifically mention suitable for motorsports & agressive driving, but personally I prefer the extended stud, everything sandwiched togeather from the hub to the wheel personally if a spacer must be used...
 
Found a local shop in town that will make anything. They can imitate the Ichiba V1 or V2 style, with or without a hub ring machined into the spacer. They can bore out the stockers as well, if I want to go that route.

Looks like my idea is pretty much what Kics already has out there - just going with a 10mm like everybody suggests is definitely the path of least resistance. Not as much fun tho. :frown:

For now I'm happy with the .25" spacer, even though it's not hub-centric. I used a star pattern and a torque wrench, stepping up twice. No vibrations at any speed. I just can't trust any shops to be as careful as I am if I need work done in the future. I can see going to the 10mm on all four wheels for a more permanent solution OR I'll just be sure to buy new rims with the right offset when the time comes. :wub:

He she is as of this afternoon:
IMG_2136.jpg
 
Been monitoring the wheel and the spacer looks to be perfectly placed. It might be that the lugs actually push through the wheel enough to center the spacer around each stud. This is stud-centric, rather than hub centric. But there are no vibrations at any speed, so I guess it works. Cheap fix, using the universal. I'd feel better if I had the jig and it confirmed everything was centered, but since there is no vibration... it's probably fine.

I plan to avoid the spacer completely by getting some new wheels with the proper offset - eventually. I just love those FX stockers!
 
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