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outlawspeeder
05-03-2013, 10:27 AM
http://i1277.photobucket.com/albums/y494/outlawspeeder/20130426_215538_resized_zps60d3efc9.jpg?

http://i1277.photobucket.com/albums/y494/outlawspeeder/20130426_172452_resized_zps78eb4c3b.jpg?

I m working on a new brake setup for a friend. The parts come three different models but the payoff is a set of brakes that will stop a freight train. It had to have 1mm off the hub and 1mm off the caliper.(done)

So my problem is how to attach the hub to caliper. The bolt is the question here. Once all this is back on the car, we will not be able to get to the head of the bolt. To add to this the head will have to be cut down in height. I plan on a press fit for the hub, and hone the caliber holes for a snug fit.

One thought is to weld on to a grade 8 bolt head to make a anti rotation lug? Can I mig weld onto a Grade 8 bolt without losing its strength?

Should I drill and add a set screw to hold the bolt from the side? The lugs are thin.
Should I braze the bolt in place?
The last thought is to “tack” weld the head? The hub is cast?
The bolt planned is 12mm 8.8 ( Im very new to metric grades)

If there is a better way … I am open to thoughts.

EVguru
05-03-2013, 10:36 AM
Caliber?

Got a cold?

rode2rouen
05-03-2013, 10:55 AM
What caliber is the caliper?


Rex

EDIT: EVguru is too fast for me, or, I spent too much time reading and re-reading the OP trying to figure out What The F!

NiftyNev
05-03-2013, 05:55 PM
Very interested in this thread because I have no idea what to OP is talking about. Will wait for someone to translate for me.

Nev.

J. Randall
05-03-2013, 06:09 PM
Pretty pictures, but I am not getting much from them. Rotors need to mount to hub and be able to rotate on most disc brake systems. Calipers should mount back to a casting that the spindle comes off of, or an axle passes through. Calipers need to be able to float on their mounting bolts. Need to clarify what you are trying to do.
James

oxford
05-03-2013, 06:25 PM
Calipers need to be able to float on their mounting bolts.
James

He is using a 4 piston caliper, 2 pistons on each side. These calipers will be mounted solid, they don't float. Calipers float when they have the pistons only on one side.

Other than that, I am not sure what he is trying to do either but it sounds like there are problems getting the caliper bolted up. I would like to see some pics of the parts on the car you are working with.

JCHannum
05-03-2013, 08:13 PM
I'm happy to hear that I am not the only one trying to understand what he is trying to accomplish. I will add, however, that if you don't know fully what you are doing when modifying and adapting brakes to an automobile, you had best not attempt it.

Machining caliper bodies and cludging up attachment hardware is not something to be taken lightly. Yes, welding a Grade 8 bolt can destroy its integrity. If this car is to be street driven and is involved in an accident and it is learned the brakes have been extensively modified by the owner and/or others, some serious damage suits could be enacted if not criminal proceedings.

interrupted_cut
05-03-2013, 08:44 PM
So it looks like the caliper sits on the back side of the spindle (not hub) from the rotor, so you can't slide the caliper with (mounting bolts in it) onto the caliper mounts at the same time you slide the rotor onto the spindle. You also probably don't have much room to fit a nut between the spindle ears and the rotor, and that is a real fiddly installation and not too secure with no good way to positively retain the nuts. When I had a similar issue putting front brakes on pavement sprint cars, I installed threaded inserts (Helicoils or Keenserts) into the spindle brake mount bosses, and used AN bolts with precison shanks of the appropriate length from the back side. I then safety wired the the bolts.

J. Randall
05-04-2013, 12:15 AM
He is using a 4 piston caliper, 2 pistons on each side. These calipers will be mounted solid, they don't float. Calipers float when they have the pistons only on one side.

Other than that, I am not sure what he is trying to do either but it sounds like there are problems getting the caliper bolted up. I would like to see some pics of the parts on the car you are working with.

Good catch Ox, didn't think that part through.
James

NiftyNev
05-04-2013, 02:58 AM
He is using a 4 piston caliper, 2 pistons on each side. These calipers will be mounted solid, they don't float. Calipers float when they have the pistons only on one side.

Other than that, I am not sure what he is trying to do either but it sounds like there are problems getting the caliper bolted up. I would like to see some pics of the parts on the car you are working with.

I have this type of caliper on my 4WD vehicle. Not modified at all, come from factory like that. Sounds like he is using a similar caliper, maybe from a Tundra or something like it, to do an upgrade on another vehicle. Would help if we had some idea what the parts are from and what they are going on to.

Nev.

EVguru
05-04-2013, 04:13 AM
Calipers are usually attached in one of three ways;

Bolts into threaded caliper bosses.

Bolts into threaded suspension upright (spindle) bosses.

Bolts through plain holes in both with a nut on the end (rare).

In this case I'd helicoil the holes in the upright.

winchman
05-04-2013, 04:41 AM
I hate to say it, but I don't think anyone really understands what the OP is doing.....unfortunately including the OP.

Welding on a grade 8 bolt is a bad idea. Reducing the head thickness is probably an even worse idea. Reducing the thickness of the mounting lugs of the caliper sounds iffy, too.

I think he's mixing part names, and calling the spindle/knuckle the hub. The caliper is mounted to the spindle (front) or axle housing (rear). The hub is a rotating part that the brake rotor is mounted to.

I'd like to see what the setup looks like on the vehicle so we'd have a better idea about what he's doing.

MrSleepy
05-04-2013, 06:56 AM
Could you square the mounting holes and use an oversized domed head coach bolt..

(assuming you could get them in a suitable grade and that removing material wouldnt weaken the casting.)

coalsmok
05-04-2013, 08:16 AM
think you need one side or the other tapped so the bolt oes in fom the outide and doesnt interfere with rotating parts

oxford
05-04-2013, 09:36 AM
I have this type of caliper on my 4WD vehicle. Not modified at all, come from factory like that. Sounds like he is using a similar caliper, maybe from a Tundra or something like it, to do an upgrade on another vehicle. Would help if we had some idea what the parts are from and what they are going on to.

Nev.

Toyota was popular for using these types of calipers on there 4x4's. I forget what years you have to use but, the Toyota 4x4 pickup calipers was a poor mans big brake upgrade for the Datsun 280z's using them and early 300zx rotors. I am pretty sure that setup was all bolt on though.

Glug
05-04-2013, 11:53 AM
Sometimes the caliper attaches to an anchor plate. The anchor plate may be a rather complicated forging, or it may just be an interface plate to match various caliper types to a spindle. This caliper looks like it may be a very beefy ferrous casting.

If you have not already done so, I suggest looking at OEM installs of this caliper to see how they mount it. Some photos of your various components - caliper, hub, rotor, spindle, etc are essential for good feedback here. Also, we need some dimensions to get an idea what we are dealing with - rotor dimensions, weight of vehicle. But also the size of the mounting holes, the expected length of the bolts. It would also be helpful to know what these parts are off of.

If you have limited space for the head, I might look at aircraft grade fasteners. However, their smaller heads are only because they are intended to be used in well engineered applications, where the engineer knows what they are doing in regard to loads, etc.

I want to repeat what others have said. The anchor fastener is under tremendous load, and vibration. Very often it will be designed so that it is under tension only, because there is another mechanism that takes the braking forces. And that is much more ideal. So if you don't have a feature like that (look at the lip in your spindle photo), the fastener is already very challenged. I sure wouldn't want to have any liability from being associated with an installation where the head of a bolt was ground, etc.

outlawspeeder
05-06-2013, 08:56 AM
Sorry about being so unclear. I know what I am thinking, everyone else just can’t read my mind.

The problem is once the hub and rotor is installed, the head side on the caliper will be hidden. The offset of the rotor means you can’t get a wrench on it. So how should I handle this. What to do for the hub behind the rotor?

Can I braze a 8.8 bolt to the cast iron hub?
Would I be better putting a helicoil in the hub?
Weld on to a bolt to make an anti-rotation lug?
Does someone make a highlock style bolt in metric (12mm) and then use a normal nut? (http://www.hi-shear.com/fastener_hl_stds.htm)

NiftyNev
05-06-2013, 06:31 PM
I am totally confused now.

Nev.

Glug
05-06-2013, 06:34 PM
I am totally confused now.


Me too.

Can't we get some parts piled together in various configs, with photos to show the fit and issues?
And how about the original and destination application? Etc.

Willy
05-06-2013, 06:51 PM
Can you post some photos of a mock up of the install with circles, diagrams, and arrowshttp://i76.photobucket.com/albums/j31/250willy/cee48e43.jpg directing us to the points you're trying make. The words aren't doing it for me either.
Like the term "head side on the caliper" for instance, means nothing to me.

No offense, but as they say a picture is worth a thousand words. Hey don't feel bad about the confusion, that's why we have cameras.;)

J. Randall
05-07-2013, 02:02 AM
Sorry about being so unclear. I know what I am thinking, everyone else just can’t read my mind.

The problem is once the hub and rotor is installed, the head side on the caliper will be hidden. The offset of the rotor means you can’t get a wrench on it. So how should I handle this. What to do for the hub behind the rotor?

Can I braze a 8.8 bolt to the cast iron hub?
Would I be better putting a helicoil in the hub?
Weld on to a bolt to make an anti-rotation lug?
Does someone make a highlock style bolt in metric (12mm) and then use a normal nut? (http://www.hi-shear.com/fastener_hl_stds.htm)

Still think you have your terms mixed up.The hub will have bearings in it, and will rotate on the axle or spindle depending, the rotor will fit over the hub and rotate with it. You can not weld anything to these. I think the others are right, we need some better pictures.
James

Jess13
05-07-2013, 02:38 AM
I think he may be calling the steering knuckle the hub, and he has a problem with one of the holes not having threads and he want be able to get to the bolt hole after it is in place.


Its going to take some pictures of the assembly being placed on the car to understand exactly what the problem is and how to correct it. If I am thinking right you will need to tap/tread one part or the other, or use Heli Coils which will still need the same work of tapping and threading. Its just a matter of which part to thread to allow for which way the bolt will need to be installed.


We need some more pictures.

Jess

dian
05-07-2013, 05:22 AM
i think op is putting the caliper on the "wrong" side of the mount and needs a way to attach it. drill out the mount and tap caliper? or use a wheel stud?

EVguru
05-07-2013, 06:48 AM
Still think you have your terms mixed up.The hub will have bearings in it, and will rotate on the axle or spindle depending, the rotor will fit over the hub and rotate with it.

A modern vehicle will often not have bearings in the wheel hub.

I prefer the term suspension 'upright' that part of the suspension that is substantially vertical and to which the wheel hub, brakes and various suspension members attach. It's a term that works for both front and rear/steered and non steered.

The original pictures show the upright set up to remove metal from the back side of the caliper mounting lugs (furthest from the wheel) and infer removal of metal from the inside of the caliper lugs. That would make sense since reducing those two mating surfaces would reposition the caliper further into the wheel and presumably inline with the brake disc.

Fixing a fastener into the lugs on the upright is unlikely to be workable, since calipers usually have to be installed radially by sliding them over the disc. A fixed stud would make this impossible. Helicoiling the lugs on the upright would work if the sizes are suitable.

Gavin
05-07-2013, 07:21 AM
I could be wrong (not an unusual event) but looking at the 1st photo posted I think the OP is intending to bolt the caliper to a fixed point using bolts through the 2 mounting lugs but with the heads of the bolts on the "inside" of the caliper - i.e. between the disk rotor and the mounting lugs - thus access to the bolt head with the rotor in place is difficult, hence the original question.

I wouldn't have thought you would use an 8.8 bolt on brakes - all the Superkart braking systems I ever worked on use 12.9 grade and this is mandated in our technical regulations.

Glug
05-07-2013, 10:14 AM
I wouldn't have thought you would use an 8.8 bolt on brakes - all the Superkart braking systems I ever worked on use 12.9 grade and this is mandated in our technical regulations.

I meant to say something about that, thanks for the reminder.

YES. The fasteners used by the auto-mfgs for brake systems tend to be really high quality stuff. They are much better than your typical hardware store stuff, due to the loads and the liability. So when someone talks about thinning the head of a hardware store bolt, holy cow. And some of those fasteners are so stress that they are "torque to yield", meaning they can only be cycled a certain number of times before they are junk.

A caliper anchor, as previously mentioned, is one way in which OEMs accomplish the type of caliper offset I believe the OP may be trying to implement.

http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0996b43f/80/20/4d/20/medium/0996b43f80204d20.gif

http://ww2.justanswer.com/uploads/VLADGMRU/2009-09-14_055339_Front_Brakes.gif

outlawspeeder
05-07-2013, 10:31 AM
Gulg,
You beat me to the pic but this is a mod of the brake system to increase the size of the rotor about 2 to 3CMs.
We are removing the anchor plate

Maybe this will help.
http://i1277.photobucket.com/albums/y494/outlawspeeder/brakes_zps3d694242.png

The mod removes the floating caliper so the parts with the “X” are not need. The replacement caliper with four pistons will mount on the back side of the hub, after the rotor/disc is installed. The hub is not threaded nor is the caliper. (yet?)

What I am looking for is a good way hold this all together. The problem is once the rotor is in place the hub is covered.

So can I thread the hub (cast iron) and will it hold up. Is there a low profile nut that can be installed that will not turn?

914Wilhelm
05-07-2013, 11:40 AM
I'm thinking threading the hub (upright) cast iron and redrilling the caliper mounting holes larger. Using fine threaded fasteners would decrease the amount of meat removed from the holes. Side benefit would be larger fasteners (greater shear strength). I would be loathe to pound wheel studs through the cast iron uprights as they may cock or crack the iron and I don't know the grade of wheel studs.

Glug
05-07-2013, 12:32 PM
Terminology... let's standardize. What you label as "Hub" is actually the "Spindle" or "Upright". The caliper attaches to the spindle. The "Hub" is the part that spins and carries the rotor.

I have serious concerns about eliminating the anchor or torque plate.

In many brake designs, the caliper mostly just squeezes the pads. The large forces that are transferred from the rotor to the pads are transferred from the pads to the anchor plate. The caliper body is not designed to take those loads. Also, the mounting ears on the caliper are offset, so those forces would cause a major twisting force on the caliper.

Looking at the caliper photo, it looks like your caliper traps the pads and the forces from the pads. But in your proposed installation, it is cantilevered out a fair distance.

Is the caliper cast iron or aluminum?

What diameter are the mounting holes in the spindle?

Changing pads is gonna be a PIA.

oxford
05-07-2013, 12:41 PM
If you went with a pressed in bolt or welded bolt, is there enough room to get the caliper on and off? What side of the spindle/upright (your hub) is the caliper going to mount on, side towards the rotor or inboard towards the motor? This should determine what needs to get drilled and tapped. If you tap the wrong one the caliper would have to get mounted before the rotor but then how would you get the rotor on?

Glug, the torque plate is only there because of the original caliper design with the pistons on one side of the caliper. The caliper he is using does not need it. Think about how a 4 or 6 piston motorcycle caliper is mounted(pre-radial mounts). This is the same thing only a larger scale.

outlawspeeder
05-07-2013, 02:10 PM
Glug
The caliper came from a car that was mounted without a torque plate. The four piston allow for the floating of the pads in place of the caliper sliding in and out. The caliper is aluminum and the holes are 12MM.+/-.5
Oxford
You are right about the bolt and we got that surprise as we were mocking it up.
So I am thinking of taping the cast (fine threads) upright, opening up the hole in the caliper to match the shank of the bolt.

NiftyNev
05-07-2013, 06:12 PM
Deleted because I think my idea was the reverse of what I thought it was. Told you I was confused. lol.

Nev.

J. Randall
05-07-2013, 07:29 PM
A modern vehicle will often not have bearings in the wheel hub.

I prefer the term suspension 'upright' that part of the suspension that is substantially vertical and to which the wheel hub, brakes and various suspension members attach. It's a term that works for both front and rear/steered and non steered.

The original pictures show the upright set up to remove metal from the back side of the caliper mounting lugs (furthest from the wheel) and infer removal of metal from the inside of the caliper lugs. That would make sense since reducing those two mating surfaces would reposition the caliper further into the wheel and presumably inline with the brake disc.

Fixing a fastener into the lugs on the upright is unlikely to be workable, since calipers usually have to be installed radially by sliding them over the disc. A fixed stud would make this impossible. Helicoiling the lugs on the upright would work if the sizes are suitable.

Seems we are gleaning a little more info a post at a time. You may choose to call the part an upright if you want, but you won't find it in any manual. I am thinking he is modifying a McPherson strut front suspension, if so the part he is describing is most probably the steering knuckle, and the manual describes the rotating part that the rotor mounts on as a hub. If you can name me a modern vechicle that mounts its rotating bearings in something beside a hub, please do, I am always willing to learn.
James

dian
05-08-2013, 05:03 AM
a lot of cars have the bearings in the rotor.

winchman
05-08-2013, 10:17 AM
I'm waiting for a picture of all the actual parts in question.

Glug
05-08-2013, 10:39 AM
At some point in a project like this, hopefully very early on, you need a stack-up diagram that shows the critical dimensions and tolerances. A DRAWING! Chicken scratch it, chalk it, whatever, and then photo it.

You're talking about having "not much" clearance for bolt heads and stuff, but we still have no idea what clearance is available.

And as winchman says, pics of the parts.

outlawspeeder
05-08-2013, 02:29 PM
I've ask for the rest of the part to be brought to the shop. Told my friend I’m at a standstill until then. I know I can’t undo some cuts.

Tim-Bob
05-08-2013, 07:52 PM
You CANNOT eliminate the caliper bracket without substituting some other support for the pads. The caliper will not hold the pads in place when you apply the brakes. Hell, it probably won't hold them in place just driving down the road! Unless I'm missing something, this is incredibly dangerous.

EVguru
05-09-2013, 06:36 AM
You CANNOT eliminate the caliper bracket without substituting some other support for the pads. The caliper will not hold the pads in place when you apply the brakes. Hell, it probably won't hold them in place just driving down the road! Unless I'm missing something, this is incredibly dangerous.

You're missing something.

http://shop.roverp6cars.com/WebRoot/Store2/Shops/es146747/5016/3351/F086/BD50/4C59/0A0F/1119/C575/type_16pb_caliper.JPG

This is a Girling type 16 caliper as fitted to Triumph GT6/Vitesse, Ford Capri/Cortina/Escort (RWD), many Lotuses, etc. etc.

It's a 'two pot' rather than a 'four pot' like the one shown by the OP, but they're generally pretty similar. The caliper is its own mounting bracket and uses pins to retain the pads.

http://farm6.static.flickr.com/5185/5687359233_26f082c5df_z_d.jpg

http://farm6.static.flickr.com/5147/5687936216_822c69b3d4_z_d.jpg

It's pretty clear to me that this is close to the arrangement the OP is trying to create. He needs something for the mounting bolts to screw into.

outlawspeeder
05-09-2013, 10:33 AM
EVguru,
You are right, I missing the pins. The caliper he is using has three pin holes. I didn’t know what they were for until you post the first pic. From that pic it filled in how the pad will mounted. Thank you!! Yoursecond and three pics are spot on minus that the one I am doing has a set of bearings in and it twice the size.
In you last photo. The two bolts that hold the caliper to the ?upright?, do they just thread in to the upright? Is it cast? Does it have inserts?

Until I get the pads, and the shaft, I am still on hold to confirm but it all might be as simple as the pad may drop in from the top of the caliper. What I mean by this…Looking at your first pic, if the pads will go in from the top, he will be able to mount it all, drop the pads in, and then pin the pads. That is if his pads are like the copper color piece with arrow and will fit.

To all, I am sorry for all the confusion. This started with a friend asking me if I could turn the outside of a set of rotors down and trim off 1mm off some parts. This is not my plan or design. I have then been given the parts then asked to figure out how to mate the two. I asked a very open question hoping to get as many thoughts of how to do this. I was not trying to be funny, I was trying to get a “out of the box” answer.
So my question remains. Can I put threads into cast? Will they hold up? I do not have a lot of experience with cast in fact I have very little with cast. Thinking back, the only other cast I have cut was for the “T” slot on my lathe.
The one thing I love about this site is every time I open a post I learn something that opens my mind to other ways of reaching a goal. So to all that say it cannot be done start looking at it as how can it be done. Someone here will help you figure out how to do it.

tekfab
05-09-2013, 11:50 AM
@ Outlaw, the upright pictured, and probably yours as well is not a casting but a forging. The pictured one above is originally used on Triumph Spifire's and Triumph Heralds and subsequently used on various race cars and kit cars. It is drilled and tapped and is weldable as well ! so don't panic. It was very common to add extremely large 4pot calipers to those uprights with simple alloy plates to space out the gap between the new caliper position and existing mount.

Mike Young

Rosco-P
05-09-2013, 12:19 PM
EVguru,

So my question remains. Can I put threads into cast? Will they hold up? I do not have a lot of experience with cast in fact I have very little with cast. Thinking back, the only other cast I have cut was for the “T” slot on my lathe.
The one thing I love about this site is every time I open a post I learn something that opens my mind to other ways of reaching a goal. So to all that say it cannot be done start looking at it as how can it be done. Someone here will help you figure out how to do it.

Cast iron or cast steel? Cast iron, I would go with a coarse thread due to the possibly large grain structure.

Final thought: can you modify these parts; should you modify these critcal braking system parts?

outlawspeeder
05-09-2013, 12:35 PM
http://i1277.photobucket.com/albums/y494/outlawspeeder/20130508_202134_resized_zps4d410aa9.jpg
http://i1277.photobucket.com/albums/y494/outlawspeeder/20130508_202257_resized_zps8586b849.jpg

I had a slug that was close to the right size to hold it together. The rotor is close. When we talked about the size of the rotor, we were back and forth on 305 or 304mm and finally joked 304.5mm. The slug does not hold the rotor in the right spot so the pic shows it hit the caliper.
So, this is a MOCKUP ONLY. I am waiting to find out if the pads are drop in (pic 2) and all this is a moot point as to how to mount this. If they are drop ins, I plan on using this setup with tighter fitting bolts. The ones in stalled are threaded to the head.

So trying to think of what could go wrong? As the rotor gets hot, it is going to grow?? 304/2 gives 107mm. Do I need to worry and if so what would be the worsted case of growth? 2 mm growth?

J. Randall
05-09-2013, 02:41 PM
a lot of cars have the bearings in the rotor.

Not unless the hub is cast integral to the rotor, and some are. That is probably what you are thinking of.
James

rohart
05-09-2013, 04:30 PM
One point that hasn't been mentioned is that I think you should use a rotor that is the same size as the one the calipers and the associated pads were designed for. It's correct to have a mm or so of rotor that doesn't get hit by the pads, but if the radius is different you'll get differential wear near the edge, which will mean you have to regrind when you change pads. Of course, you could solve the problem after the event by shaping the outside of the pads to match the curvature at that distance from the axle.

On the subject of floating vs not, I've only driven floating on the Fiat 124 series. Since then, my Alfas and BMWs have been non floaters, and I think 1970s British Fords were the same. Two high quality bolts for each caliper, though I can't remember what they were tapped into. Ford used one long MS tabbed washer across the two bolts, folded up onto the flats.

As for holding the pads in, there's very little force on those pins. Alfas had the pins turned down at the 'sharp' end to about 3/16", and the pins were located by a sort of spring around the head end that buried itself in the hole in the caliper. There was a nice bent spring steel contraption that forced the pads away from the pins and towards the axle, probably to help prevent squeal and rattle. It probably exerted about 15 lbs of force against each pin.

winchman
05-09-2013, 05:09 PM
Could you make a special wrench to hold the head of the bolt while you tighten the nut?

Where is the bleed port for the caliper going to be?

outlawspeeder
05-10-2013, 12:33 AM
The bleed port out of the way and will be the high point. The thought of a special wrench, that is a thought.

winchman
05-10-2013, 01:22 AM
Two more possible solutions:

Machine flats on the threaded end of the bolt so you can hold it while tightening the nut.

Use a bolt long enough so you can have two extra nuts jammed together so you can keep the bolt from turning while you tighten the third.

NiftyNev
05-10-2013, 03:59 AM
One point that hasn't been mentioned is that I think you should use a rotor that is the same size as the one the calipers and the associated pads were designed for.

Exactly. The rotor OD and it width should both match the caliper. Bad idea to start mixing parts that are not designed to work together. I'd like to also know what he will be doing about the master cylinder etc.

Nev.

outlawspeeder
05-10-2013, 08:59 AM
I like the thought of three nuts. That is something I had not thought of.

The master cylinder is the one that matches the caliper.

EVguru
05-10-2013, 09:23 AM
Many uprights would be tapped for the calliper bolts, there should be no problem with doing so. The Triumph upright is tapped 7/16 UNF as I recall. Using a helicoil may halp match the shank size to the caliper lug holes better.

winchman
05-11-2013, 01:11 AM
Would it be possible to bore a hole in the hat section of the rotor so you can get to the head of the bolt? I've seen some axle flanges with rather large holes in them to provide access to fasteners behind the flange.

http://www.metropartsmarket.com/rearend/Axle_28_Spline.jpg


Have you considered using a lug bolt with serrations on the shank? If you pressed it in beforehand to cut the serrations, you could get it bottomed out in the final assembly without needing so much torque.

tekfab
05-11-2013, 03:13 AM
Here's what you do, you make a flanged insert, drilled and tapped internally to suit your mounting bolt. The length of the insert is thickness of lug + bolt head thickness. You bore the lug on the upright to suit your insert and NEATLY tig weld the insert to the upright and hey presto you have a nice mount. Depending on the size of that mounting lug it is sometimes possible to offset drill the holes to give the caliper some more radial clearance on the disc or machine the diameter of the disc down to give you clearance required. If when mounted the disc (rotor) does not sit central then add shims (washer) between the caliper and the upright to centralize the disc (rotor) in the slot.

Mike Young

outlawspeeder
05-13-2013, 11:19 AM
I got the hub over the weekend but I haven’t had a lot of time to put it all together to mock it up. I did hold it together and look at it. The rotor fits but will still need some more cut off for safety.
I still think that I might be able to get a short bolts in there and still get the caliper on over the rotor. The pads do drop in and get pined on place.
Thanks for all the help up to this point. It will be great to get this one out of the shop.
New shop rule: I get all the parts to mock it up before the friend leaves. This way I don’t have to guess at how it all fits together.