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I will look, but if all I can get is the 17x26mm O.D. bushing, than Bamm, still in business. As you said just have the outside turned down to fit what I need.
So if I want 1/8inch thick bushing, than I should do a 13/16 inch hole, might have to do 7/8" because of what drill bit is available to me, but I got your point Larry.
Any ideas about drilling the hole, do you really need to slowly increase the drill bit size until you get to the size you want ?
Step drilling helps. Step up however whatever drills you have.
But the last step before finish should be barely less than finish size.
The lighter the cut and the sharper the finish drill is, the more accurate the final size.
So....twist drills typically are only good to +.005 tolerance.
In a machine shop you would step drill it up to .015 under size and then put a reamer through it.
I was never told about it that way. If I get the larger tolerance in bushing size than a 3/4 hole will be undersized a little.
The brake support bracket is the hard one, not lot of room and all the bushings have large OD to them, so I will just get the bushing turned down to press fit into the bracket.
Enough work for the day.
The bushing that is located in the caliper support bracket which rides on the 17mm axle.
Now I had planed on just drilling a 3/4" hole like on the rockers, but I see the rockers will need to be larger at 7/8" dia for the axle hole so I can use that larger bushings so I can ream it out a bit for the 17mm internal dia.
*** the question is how much bushing is truly needed on the support bracket ?
the 3/4" OD x 5/8 ID bushing will give me 2mm of thickness of material after I ream inside to 17mm dia.
This is close to 3 / 32 of inch thick bushing, shouldn't this be enough for the support bracket to roll on the axle ???
If I am understanding correctly...your axle will be fixed, the only rotation will be the caliper mount itself, and it will be only a few degrees when the brakes are applied. A bushing wall of 3/32 would be fine , The main reason for the bushing is to avoid the undesirable situation of having steel on steel. Hoping I'm on the right track here?
Going back and looking at the numbers......it look like my bushings are .125 wall
The main reason is that they are off the shelf items from any industrial hardware supplier. MSC, Granger, McMaster carr, ect.
Also.....you keep saying "on the axle".
I am not sure what you mean there.
The axle for the wheel itself will not have any bushings on it.
The brake stay will be on a bushing that rides on the axle spacer.
I suppose you could make up the bushing as a replacement for spacer length. That way the stay would rotate on a fixed bushing. But I would not want brass as a spacer. Would prefer the axle be more solid tight.
Attempt a pic. But it is hard to tell the stay is on the od of axle spacer.
I barely can see it, but I do see what you are talking about. I got it wrong from the start than as I thought it just road on the axle and that is why it needed a bushing in it, so the bushing wore not the axle or bracket.
This rim, rotor, and factory spacer out of the hub allows the support bracket to mount flush up against the hub spacer, this is in alignment with the rotor for caliper mounting.
I take it a thin friction shim should be between the hub spacer and the bracket, spacer is aluminum and bracket is 304SS.
I see if one long spacer was used, to cover distance between rocker and factory hub spacer, and if is press fit onto the spacer at the end, that would work, but my mind says I still should use a friction shim between things.
Oh, my mind is gone, a 3/4 OD and 5/8 ID, does not mean a 1/8 inch thick bushing, it is only 1/16th of inch thick on each side, duh...…………
So is that right size to use on the 5/8" shoulder bolts on the rocker arms ? or do we want the bushing to be 1/8th inch thick wall ??
If I got this wrong I have to change things up and go to 7/8" OD on the hole with the 5/8" ID, guess would not be bad as I have to do that up front for the axle hole, go 7/8" OD and have the inner reamed out to 17mm, that is if we want the thicker walled bushings.
got it!....no part of the axle bolt 17mm diameter is exposed. Just axle spacers....true you must pivot the caliper mount on one of the spacers. I've got a drum up front, so reaction link to the bail, which I have since learned should be to the fork tube. maybe this winter...
Getting back to Andys mounting plate
are there any provisions needed to prevent side to side movement on the caliper mount?
Let's get it started correctly.
The axle is 17mm dia. and is a fixed axle, meaning the rocker arm will have a set screw in it to hold the axle in a fixed position.
Rockers can collapse inward if spacers are not used, I will need spacers to keep the wheel hub centered on the axle.
side to side movement, well if brake stay was pressed on a bushing and that slides onto the axle and than the final spacer, the brake stay would be kept in it's location by the two spacers, and of course we have the reaction arm that will hold the brake stay from rotating to far.
So we use a press fit bushing on the spacer. The spacer will roll on the axle, if not, than the brake stay rolls on the bushing that is pressed to the spacer ? Or is it do to the fact that the spacers all push up against each other and this pressure keeps them from rolling around the axle ? so for this reason the brake stay must roll around freely on the press fit bushing on the spacer ?
If you press fit the bushing into the brake stay, than as the brake stay rotates a little the bushing rolls on the axle, not the steel brake stay...….that is what my mind has always seen, spacers on each side keep all in position and centered.
I say the question is which method gives the most free movement, eliminates the chance of binding...….and I think my idea or way, well is seems it could have more pinch or binding because more parts are involved.
but if you tighten up the axle bolt to much than spacers bind up on each other and my way is not freely moving.
I see if brake stay was riding the bushing on the spacer, well brake stay will still rotate on the bushing that is fixed to the spacer.
So if this is the case, I will need to drill a much larger hole for the large bushing.
17mm dia. axle, 19mm = 3/4", so that is a 1mm wall thick bushing.
So a 1" OD bushing with a 3/4 ID pressed onto a spacer that is 3/4" OD with a 17mm ID, but the spacer has to be fixed so that the movement of parts are on the bushing and not spacer to axle area ?
Do not pin or set screw the axle.
Axle must be solidly tight. You will get some weird flex and gyrating if loose.
The best way I have found is turning a step on a spacer and press bushing into stay method.
In mine I was able to up-size the seal and that gave me the meat (metal thickness) to work with.
That axle is tight.
Stepped spacer.
Bushing pressed into stay.
Trapped between rocker side and step shoulder. And by trapped I mean just enough clearance to rotate freely on the stepped spacer.
I said set screw for the axle as I seen it being done, and it might have been on the Triumph search. Some do odd different things. I looked at it as the extra measure to help secure the axle distance between the rockers. Just say you have 7" distance needed for everything, even that little extra clearance for free movement, you tighten up the axle nut to that key position, and I thought the set screw just help held all in that position just in case the axle nut backed off for some reason.
Not done, just a thought, so eliminating that thought.
Now on to the brake stay set up. I see what you did, that is the ticket. Just turn the OD of the spacer down enough to hold the bushing on the end. Nice tight fit so bushing is not rolling on spacer, spacer cut to correct length hold the brake stay in it's positon, no side to side movement.
I see this all working. Now I will get to the drawings and material and see if I can make it work. I have to have enough metal at the lower end of the brake stay for the larger bushing dia.
I need to do this, getting this nasty feeling in my stomach, like I may not have enough material for such a correction.
The nut does need some kind of safety back up.
A lock nut, a castle nut and cotter pin, ect.
Something that if the nut gets loose it dont fall apart.
I suppose a set screw in the right place could do the same thing.
The Dewalt 1/2" bit took forever to punch through, but got it done, started on the 5/8" step.
Now I checked it out, if I go to a 1" hole in the brake stay, than I have 3/16" thick distance to the outer edge of the pattern. And I corrected myself, press fit bushing into brake stay and let the bushing roll on the stepped spacer.
I did some looking for spacer's, did not make up my mind yet, as the available size varies on what type of material, so first I need to find one large enough for what I need.
If I go 1" OD on bushing with 3/4" ID so I have 1/8" wall on bushing, well the spacers wall thickness will only be 2mm thick for the 1/2" distance the brake stay and bushing take up, than the spacer steps up in OD and a thicker wall, but for only 6/16" of an inch, the total length for the spacer is 7/8".
More drill press time.
Still on the drill press, but when I was thinking about it all I do believe that the meat of material should be on the step spacer, if the flanged bushing is to revolve on it.
So I have the flanged bushing with a 1" OD and a 7/8" inner dia., custom cut to 3/8 " long for the brake stay, bushing press fit into brake stay.
The 1 1/8 " OD spacer with the 17mm ID will have 1/2" of a end turned down to the 7/8" dia. for the brake stay bushing. This basically gives a little over 1/8" thick spacer wall where the flanged bushing will ride. I am still looking over McMaster site for what is needed.
sounds like you have got it figured out.....I would not want any less than 1/8 wall on the spacer, that said, there is very little clamping force on the axle bolt/nut. But you don't want a thin spacer compressing and making for a loose axle bolt. There may be torque figures for the bolt. maybe Rex has a figure. On my setup the spacer for the wheel bearings was about 1/8 wall if I recall correctly.
I do not like, or trust nyloc nuts......I use castle nuts and cotter pins, maybe old school, but things stay together.
Rex, just hold the drawing of your setup in front of the mirror, than you see what mine is.
The idea of stepping down the spacer creating a lip to hold the brake stay/bushing in position is a solid way to do it. The flange of the stay bushing will be facing out ward towards the rocker, but for alignment the brake stay's position is up against the factory seal spacer, in fact for the final alignment step of it all that factory bushing might need to be shaved a little, or shimmed out away some. The location on the spacer step will solve that issue.
3 1/2 hours on the drill press and not even half way yet, and a hard day today, so maybe tomorrow I will get more done.
Hope all have a good night.
A 17mm fine thread would be around 150 ft/lbs.Originally Posted by LarryA
So it did take another 3 1/2 hours or so to get the 5/8 " holed drilled, but the drill bit does not even looked used, okay some people can tell you it was used.
I was wondering about that torque setting, thank you Rex and Larry.
Help me understand why the Brake Stay bushing can not ride on the axle.
How do I keep the brake stay in alignment, the inner side rides up against the factory bearing seal spacer, right now all says that is dead on the mark, and the outter side of the brake stay is help by the larger dia. spacer that is between the rocker and the brake stay.
I ask because I made the brake stay with 3/8" clearance around the bushing hole, that is is if it was 3/4" OD.
Now, well if I go 7/8" OD on the stay bushing, we have a heavy 1/4" material left, if I go to the 1" hole we have only 3/16" of material around the bottom/sides of the hole. With this being 3/8" thick steel would this 3/16" be enough material around the bushing hole for the brake Stay ?
I thought I had the step spacer ordered, but in the end I have to order 5 of them minimum, and at 36.00 each, I had to pass on it, but most of the other hardware is on the way here.
I ask this because, if a steel spacer is riding the axle and the brake stay bushing rides the spacer, axle still gets wear from steel spacer. My mind says it would be more wear than that of the brake stay bushing riding on the axle.
I do pray this 3/4" hole drill's much easier than the past holes, a I am getting a bit worn out with it.
I hear you about the step spacer, a very solid idea, Bammmm! just hit me upside the head......The overall distance the spacer covers the axle is side to side strength, plus the step design gives side strength in holding position. This is far more than the 3/8" wide brake stay would cover. Yes it would have side support, but just not the same overall axle support. I am good, I see why and how it is better than the other way. I am sure each way works, just one is a better method than the other. I will spend more time trying to find my step spacer material today.
Thank you all and have a great day, Hump day it is, in enjoy it my friends.
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