Wheel/Axle installation

[cajunpilot 0]

In the process of installing the wheels on our Mark IV Avid Plus. Manual says to align backing plate with the Brake disc. While at factory assist @ airdale crew cut spacers for installation. Upon installation of the wheels it became apparent that the alignment is not 100% flush.

My question is about this alignment. How important is it that this be exact? If it is then it appears that we will have to re-cut the (inboard) spacer (larger) to a more precise alignment.

Sincerely,

Greg

New Orleans, La.

[akflyer 1427]

how far out of alignment are you talking here?  The caliper is floating so it does not have to be in 100% perfect alignment, but you dont want it 1/4 " out either.  Another way to get it is to run down to the hardware store and grab some 3/4" machine washers.  Put them between the gear leg and the spacer.

[dholly 718]

HI Greg,

Tell your old man (Hi John, thought you'd be flying by now with all that help!) to get a camera, us Yanks don't visualize all that good. A pic is worth 1000 words and the ability to post 'em here is one of the reasons this forum rocks! Besides, he told me 2 years ago he was going to email me some pics of your project, never thought an old military man would welch out on his word...  

Now, may I assume you are referring to the steel spacer that is slipped over the axle?

[edit] holy crap that 1st attachment was huge, I've resized to just plain 'ol Fat

[akflyer 1427]

and the good sense of humour is what keeps me laughing and the site up!

[akflyer 1427]

HI Greg,

Tell your old man (Hi John, thought you'd be flying by now with all that help!) to get a camera, us Yanks don't visualize all that good. A pic is worth 1000 words and the ability to post 'em here is one of the reasons this forum rocks! Besides, he told me 2 years ago he was going to email me some pics of your project, never thought an old military man would welch out on his word...  

Now, may I assume you are referring to the steel spacer that is slipped over the axle?

[edit] holy crap that 1st attachment was huge, I've resized to just plain 'ol Fat

you think an ole coonass from the swamps is gonna figure out how to post up the pics   There is hope, I figured out how to merge the topics so my coonass cousin has a shot at posting pics!

Keep the questions coming Greg and John, it is well past time for you bird to be in the air!

< if you use the chug, all slights and pokes are then deemed as acceptable good natured ribbing and therefore AOK

[cajunpilot 0]

Hello from Cajun Country,

Home to the best Collegiate football and Baseball teams in the world!!

Thanks for the information.

Your help is MUCH appreciated...I think I have been since we got rolling wiht this. I have an Air Force Mechanical background and these manuals...well, let me just stop at saying they are not as exhastive as I would prefer.

I am attaching a couple of photos. from the pic you can see that in standard measure its approx 1/16 out.

So, please tell me what you think. you help is mUcho appreciated!!

Keep your Flaps Down...

[cajunpilot 0]

One other question for you Dholly,

In the picture you have a spacer between the two bearings. Is there a reason for that? I ask because a third spacer has come from the factory with no apparent application other that might be a space with which to cut additional spacer from.

Greg

PS re: previous post...too arrogant to use spell check but being humble by post post proof read I am now a believer

attachment: First time the Fat Bas**** stood on one of her own wheels. Felt good to accomplish! 

[akflyer 1427]

looks like one 3/4" machine spacer would do the trick perfectly.  As I said before, the calipers float, so I would think it would not really make that much difference, and unless you pointed it out when she was all together, no one would know the difference.

[cajunpilot 0]

Okay, thanks!

My only concern way side loading or some other nonsense. call me anal retentive.

Thanks for the advice

;D

Keep Em' Flyin

for any intersted, I did post some of the build photos on FB "Gregory Bowman"

[akflyer 1427]

you the one with no info on the profile that shows where you are located   There are a couple choices and I didnt want to carpet bomb the others to find the right guy lol

[dholly 718]

Greg -

This 'issue' is starting to ring a bell. Is the manual referring to the caliper brake plate OR the torque plate? It's been a while but I remember assembling the wheels and brake assemblies and mounting to the brake torque plates on the gear (I did my first major screw up in the process but that's another story) and thinking the same thing ie., the brake disc did not fall directly inline with whichever. It was one of those things I needed to revisit when I had the wheels mounted properly. At the time I just clamped on a set of temporary axles without drilling and bolting the gear legs in order to get the fuse mobile because I was making up new axles with tapped ends for wheel pants and skis. But I think the offset was close to what you mention, about 1/4", and I believe that was to the inside.

That makes a difference because the inside pad between the disc and wheel is the fixed pad and the outside pad is the one that moves. Too much offset to the inside could cause the outer caliper housing to hit the slide stops on the outside with pedal pressure, right? Gotta think if that has a seriously negative impact on brake force... I dunno, late in the day and not thinking too quick at the moment... maybe worse case is you suffer uneven pad wear? Can't tell much from these pics but it gives a rough idea how my offset ended up with the spacers provided.

And you sir, are correct, the manual sucks! Actually, all I have is a Mk-IV manual with a handful of pics that try to visually explain some -not all- of the dis-similarities, but certainly no written updates applicable specifically to the Avid+. I may have gone to the Matco Mfg website to get a blowup schematic to determine how the axle spacers went.  -Doug

[dholly 718]

And just in case you want to go crazy on the brakes, this rotor drill pattern should work if you have the WH62 assembly.  ;D

[cajunpilot 0]

Many thanks, I feel the shackles falling off. I will bring the spacer with me but I am unaware of anyplace as of yet I can get to machine of the proper length. The idea of a washer sounds like the best avenue (at least doe the time being).

Once I have the proper alignment between the brake disc and the "Brake Backing plate then I can drill, pack and mount the shaft. I have a drill press so this should be as anything else we have done so far....hear that noise...me knocking on wood  or maybe it just sounds like wood, I deny any rumors as to my hardheadedness. Those people just could not see that I am always right!!

So in synopsis, headed to Lowe's to get two of the a fore mentioned washers. I am not sure if I mentioned this but looks as the variation is out 1/16 of an inch. And, yes it is to the inside. This is as you mentioned the mechanical variance that cause me to be concerned. Even if it is a shortened life span due to ware pattern.

Last bit is...Is there anything I need to watch out for when drilling the hole through the threads for the castle nut and cater key? I DO NOT want to screw up these axles and this seems a very touch part of the Job.

"Two things you cannot use...Altitude above you and Runway behind you"

Eddie "Ace" Duffard

My Ab Initio instructor and a legend in Louisiana Aviation

87,000 Hrs 80% of which was flight instruction

,,,

[dholly 718]

I think using a drill press for this is a much better idea than attempting to 'free hand' it. I would assemble everything and mark the position of the axle, then remove the gear leg and drill through both the gear leg axle tube and axle at the same time. Go slow, start small and work your way up with sharp bits and plenty of cutting oil. Once the axle is bolted in and everything reassembled you can finalize the location of the axle nut cotter pin hole, mark and take just the axle to the press and go to it. YMMV but that's my plan.

Also, on the outside chance you did not see this, Matco included the attached warning about proper technique for torquing tapered bearings. Axle nuts should be tightened until all play is out of the assembly. Rotate the wheel back and forth while tightening the the nut to help seal the bearing. When all play is out of the assembly, and the wheel rotates freely, tighten to the next castle slot and insert the cotter pin. The rubber seal on the tapered roller bearings will remain stationary while the wheel rotates around it. If the seal is spinning on the axle, the nut should be tightened further until the seal stops spinning with the wheel. It is important that the nut torque be sufficient to keep the seal from rotating with the wheel.

[dholly 718]

Sorry Greg, didn't see your other spacer question.

My manual (Rev 8/16/96) Sec II-D, Chap 2 says:

2. To keep the bearings from turning on the axle, cut a bushing from 7/8" tubing, 1.2 inches long, to act as a spacer between the bearings. See Photo F2-6A

It's all coming back to me now, both the steel spacers and the copper spacers I received were pre-cut.

[cajunpilot 0]

Okay,

Well, that answers that as I have seen illusions to that effect somewhere (reference to a bushing in between the bearings). Okay as far as the tubing is concerned, what material do you think it should be made of. Seems to me that some of the spacers appear to be copper but that cannot be correct due to heat concerns ...can it? I only ask as I am going to have to replace the center spacer on either one or both of the axles, as I used a pipe cutter to cut an additional bit of spacer due to our alignment problem. It worked great. All lined up, but short one spacer... 

Okay well this should not stop me as to drilling my next axle. Oh did I mention, drilled the first axle. The main problem with a drill press is the unusual shape to what you are drilling. Two man job and then still moved off my alignment mark. Had to re-cut additional outboard spacer.  Yeah , what fun!

I will have to wait til the am to go buy the additional tubing for interior spacer for both wheels.

PS Our manual has NOTHING regarding what you are talking about. Thank you so much for that.

Gonna be sick of us before its all done I'm afraid. No end to how much I appreciate it.

I am not sure what you are saying about location , but if it is in reference to Facebook I am located in New Orleans

[dholly 718]

Greg-

Instead of lining up the tube by eye and trying to hold it while you drill, here are a couple of tips:

First, try the old machinist's trick of capturing a thin steel rule between the tube and the bit; when it doesn't tilt, the bit is centered on the work (this originated for centering a lathe bit against the work piece, but will work as well here). Remove the rule and make a light centering mark with the drill bit, then center punch the axle tube to provide a straight start. Of course your drill press should keep the bit vertical; but definitely use a pair of V blocks to get the through hole exactly 90* degrees to the tangent of the tube and appropriate clamping hardware to keep the gear leg from wandering.

And about those build pics... any way to share with non-Facebook members?

[jbowaaf 0]

Doug,

Thanks very much for the machinist advice.

one Gear down, completely packed and locked on the axle. YAHOOOOOO!!!

Okay as to posting the pictures, yes, I am going to Photobucket the whole thing as well as maybe setup a webpage for the build...have to see about last....not too literate round these parts...fangled computers....

Its hard for me to post here as if I try and load more than two pics it times out...site doesn't like coonasses

Either way Ill grind out a way.

Speaking of grinding, well cutting (hacksaw through steel 1140) then grinding smooth, the ol' coonass is out there as I speak...ops type, cutting our new spacer.

Not sure about ability to post this but I would like to start a builders assist thread part to this site. I did a complete video of my installation of the RT MLG wheel assembly. Its heavy file wise so uploading I don't know about but I would have killed for this much information at the start...thinking maybe other poor schmucks out there like the LSU adoring Gift to the Cajun skyscape.

Let me know what you guys think...even if its to post detailed pics with experiential information along with...much like a narrative...

[akflyer 1427]

there should be way more than enough bandwidth to handle any build thread you want to do.  If not I will buy more

[cajunpilot 0]

Okie Dokie,

The reason I asked is that when I tried to load three pictures. It timed out on me. I am thinking a video which is going to be huge would fair very well either.

What do you think?

Keep your Flaps Down

[akflyer 1427]

hmmm, let me check settings and see whats up with the uploading.  may be time for me to upgrade software...

[dholly 718]

Hey Greg, you might try resizing your pics before posting. You are sending 2448x3264 pics which are G-I-G-A-N-T-I-C and probably do take a long time to upload. When I click on the thumbnails they blow up so big it's sometimes hard to see the forest thru the trees, if you know what I mean. I use Microsoft Image Resizer for XP, free download HERE. Once installed, all you have to do is right click on a pic and select a new size. It makes a smaller copy and leaves your original intact. Quick 'n easy, I think the Medium size works best. Let's plaster Leni with pics!!!

[dholly 718]

Anyone with Airdale's W.I.B. (wider is better) main gear, I'm curious how you mounted your brake calipers to the gear torque plates. As I mentioned earlier, this step caused my first train wreck. Because it's raining like crazy (AGAIN), I'll share my embarrassment.

The Avid Mk-IV manual says to mount brake calipers at a 45* degree angle aft in relationship to the ground level. According to Matco Mfg Assembly Information, the ideal mounting position for the brake caliper is the trailing side of the wheel at 270* degrees from vertical, with the inlet and bleeder valve in a vertical axis. Therefore, it would seem that a 45* to 90* degree angle aft in relation to the ground is the preferred range, although Matco also says the caliper can be mounted at any location as long as the system can be bled of air properly.

Since the caliper backing plate has 8 holes and the kit supplies 4 bolts, it's only natural to space your bolts evenly in every other hole. I felt there was enough room to do this and drilled the holes. Unfortunately... one hole ended up slightly too close to the gear leg and, even with a modified washer, the weld bead prevented the washer and nyloc nut from seating flat.

Urrgh! No way around it. Got the welder out, filled the holes, ground smooth and re-primed. Final position of the calipers relative to the ground is not quite the best per Matco's recommendation, but it is as close as possible when working with the fixed gear leg and torque plate and pre-drilled backing plate holes.

So how did you guys make out? Same bolt locations or different?

[akflyer 1427]

You bolt pattern looks just like I did on my gear, but I had home made backing plates.