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dr pepper
12-07-2010, 08:01 PM
I am converting my classic land rover to discovery axles, for several reasons, one of which a more suitable diff ratio for the range rover engine.
This requires 'moving' the holes in the flanges on the ends of the axle by 8 degrees.
This means that the holes are moved around so that the new hole is 1/2 in new metal and 1/2 in the original hole.
I've machined up jig plates to drill the holes with.
I started out by filling up the old holes with mild steel allthread bar, welded up at the back, I did this as drilling/tapping weld is not something I wanted to do which would be the case if I just fully welded up the old holes.
Problem is tapping 1/2 allthread and 1/2 steel is very tricky I think the allthread bar twists a little from front to rear as I turn the tap gripping it, I did one side but now its time for the other side.
Are there any little tricks I can do to make this easier, or shall I just tackle the job the same as the previous side.
I didnt want to remove or make new flanges as I dont have the measuring facilities or equipment to postion the flanges square, so re-drilling is the only option.

http://www.landyzone.co.uk/photopost/data/500/medium/Picture_0117.jpg

strokersix
12-07-2010, 08:20 PM
I must be missing something. Why didn't you just clock the holes further to drill into solid material?

dr pepper
12-07-2010, 08:41 PM
That would have made things easy, the hubs have to be rotated 8 degrees to get the corect castor angle, and the correct diff drive flange angle, thats why its like it is.
Could do with some means of locking the front end of the allthread to the flange, I dont want to weld it as the casing wont go in my mill to reface it, the back edge isnt a gsket surface so doesnt matter as much.
Maybe a 3mm or 4mm grub screw screwed in on the edge of the 10mm plug opposite the new hole might do the trick.

Carld
12-07-2010, 09:17 PM
Couldn't you just wedge the spring pads 8 deg and achieved the same thing?

gnm109
12-07-2010, 09:21 PM
Couldn't you just wedge the spring pads 8 deg and achieved the same thing?


Good idea. Also I recall from my hot-rodding days that spring shops have those tapered shims or wedges if you will available in different angles.

dr pepper
12-07-2010, 09:58 PM
yes I spose I could.
8 degrees is a fair old setting, and also I have spacers under the axle to lift it up to clear the different steering track rod, the angle plate would angle the axle in the opposite plane bringing the track rod closer to the springs which would require even more spacing under the axle losing ground clearance.
Its been head scratching all the way, and a few have said why bother.
I dont think theres a way of avoiding the drilling, more a case of doing it so that the holes will tap easily.

Don Young
12-07-2010, 10:16 PM
A permanent locking Loctite or just an epoxy such as JB Weld might give you enough additional holding to keep the inserts tight. You would have to be sure the threads are clean and oil-free. Don't let the adhesive get hot when drilling. I would try this first as I have done similar work repairing holes that were stripped and drilled crooked. Strength is rather remarkable if there is a lot of good clean contact area.

If you have the capability you could turn up some inserts with a slightly oversize thread so they would screw in tightly, but they might loosen when you drilled the new hole. Something like tapered pipe plugs might be another possibility.

Would it be feasible to relocate holes or studs in matching part so they can all be in totally new material?

dr pepper
12-07-2010, 10:52 PM
Thats a good idea, I have some structural strength loctite adhesive, and some quick metal, might just make a dummy jig and see if it works.
I have a thread cutting lathe, with the correct back gears, what kind of oversize would you turn it up to +0.05mm?, I cannot go really tight as screwing it in would be an issue, I have to screw them in with a flat blade 'driver.
My backup plan is along the lines of relocation, if a forbidden tap breaks or hole screws up then I'd make a thick washer cut into 2 c shapes, with the holes tapped in the right places and put this behind the axle case flange and drill out the original flange holes.
I have a rough but effective spark eroder built from junk for demolishing broken taps and bolts.

Evan
12-08-2010, 12:08 AM
Drill and tap an 8-32 hole in the edge of each inserted part on the side away from the hole. Twist in a set screw.

I see it was mentioned earlier. I think it is a good idea. :D

spkrman15
12-08-2010, 12:16 AM
Dont' use allthread. It is the lowest grade possible. Unless you have specifically asked for a grade

Drill out the old holes, insert a plug and weld them at both ends. Grind smooth on the ends. Center drill, drill and tap.

Buy a new tap. Seriously. This is an important job. Buy a damn good tap. Not the pepboys or Canadian tire one. KBC, SOWA, FULLER, etc.

Good luck DR Pepper,

Rob :)

dr pepper
12-08-2010, 12:24 AM
I used a new tap on the other side, a dormer as used by aerospace, spiral taps as used by cnc's are a little expensive.
Maybe I did the wrong thing with the allthread, I didnt want a high tensile bolt as I was concerned about the drill wandering into the softer flange metal, as is allthough not perfectly square the hole is parallel right through.
I dont know what the flange is made from it doesnt look flame treated or anything.
The screw opposite the hole is what I'm going to do different on the other side, welding the outside edge of the flange is a preffered not to do as if I atack it with a grinder afterwards I'm gonna get leaks.

Evan
12-08-2010, 01:28 AM
About the leaks, fill the housing with about a cup of wheel bearing grease. That will mix with the oil and make it much less likely to leak. I rebuilt the front end on my Series II including the u-joints and all the seals on the Swivel Pin Housing back in the 1970s and it hasn't leaked yet.

Which model is that?

dr pepper
12-08-2010, 01:36 AM
Never heard that one before, done that on chains but never on an axle.
Mines a kid compared to yours its a '80 series 3 long wheel base with a mil hard top back.
Was a petrol, now a diesel with discovery axles.
I wouldnt butcher a series 2 or 2a.
Glad to see yours is still running.
Mi dads old '70 swb is still going, and my mrs had a lwb mil petrol '71 for 15 years, thats still going too.

mike os
12-08-2010, 03:59 AM
is it just me that does not like the look of that?

Evan
12-08-2010, 08:24 AM
It'll work just fine. The old Rovers are built like a tractor. In fact, that is one of the uses it was intended to fulfil. Mine is over 50 years old and the engine has never been rebuilt. It could use some new valve guides and maybe some oil rings but it runs just fine. I started it without trouble at -15 the other day without auxiliary heat. I use it regularly on the property all year long.

The body is aluminum and the chassis is hot dip galvanized as are nearly all othe steel parts. The entire thing is bolted together and can be stripped down to a chassis in a day. The tranny lifts out from the top after removing the bonnet, folding down the windscreen, unbolting the hood and removing the seat base.

It has a 45 hp engine and in the lowest gear the total drive ratio is around 44 to 1. I can lift off the driver's door so that I can walk along beside whilst steering so I can see what is going on better. It has a hand throttle to set rpm's and is rated at a full half ton cargo even though it only has an 88 inch wheelbase. It will pull stumps, pound posts and grade my driveway in summer. I plow snow with it in the winter and the heater even works.

http://metalshopborealis.ca/pics5/roverlog1.jpg

http://ixian.ca/pics8/rsnow1.jpg

dr pepper
12-08-2010, 06:12 PM
Yep I agree with all that.

Lannies are still popular in the south of england for farming, they have a PTO shaft at the back to turn farm plant.

Cept for one thing, the heater works?, it'll be the first one that does, obviously not the round smiths type.
The engine must be sound if it'll go without glow plugs, I've worked on similar engines but marinised and only a couple would go without heat even in summer.

I see your in Cariboo Canada, you see these trucks all over, lannie reckon a third of the population saw a landy as their first motor vehicle sighting.

Oldbrock
12-09-2010, 01:22 AM
I think I would use a pipe tap on the original hole and use a steel pipe plug and tighten at tight as I could with locktite. Shouldn't need to weld. peter

mike os
12-09-2010, 03:34 AM
Cept for one thing, the heater works?, it'll be the first one that does, obviously not the round smiths type.



Please dont use words like landrover, heater & work in the same paragraph :D the usual, pick 2 out of 3 LOL

oldtiffie
12-09-2010, 05:45 AM
I am converting my classic land rover to discovery axles, for several reasons, one of which a more suitable diff ratio for the range rover engine.
This requires 'moving' the holes in the flanges on the ends of the axle by 8 degrees.
This means that the holes are moved around so that the new hole is 1/2 in new metal and 1/2 in the original hole.
I've machined up jig plates to drill the holes with.
I started out by filling up the old holes with mild steel allthread bar, welded up at the back, I did this as drilling/tapping weld is not something I wanted to do which would be the case if I just fully welded up the old holes.
Problem is tapping 1/2 allthread and 1/2 steel is very tricky I think the allthread bar twists a little from front to rear as I turn the tap gripping it, I did one side but now its time for the other side.
Are there any little tricks I can do to make this easier, or shall I just tackle the job the same as the previous side.
I didnt want to remove or make new flanges as I dont have the measuring facilities or equipment to postion the flanges square, so re-drilling is the only option.

http://www.landyzone.co.uk/photopost/data/500/medium/Picture_0117.jpg

Hi Dr P.

I've waited to see what came up, but as it has slowed a bit I thought I'd make a suggestion.

If it were me I'd have milled out what was required so as to leave a machined "kidney" shape in all of the holes.

I'd have made/turned cylinders the same size as the holes and just a bit shorter than the flange width. I'd have milled flats on those cylinders until they just fitted between the bolts and the "kidney". I'd have used the "dips/hollows" where the bolts and the cylinders with the flat faces meet, and lightly tack-weld them together.

The bolts and cylinders are now "captive" in the kidneys.

I'd make three substantial,"kidney-shaped" "washers" (flat) and as there seems to be 7 holes I'd make three "kidney washers" - 1 to span 3 holes and 2 each to span 2 holes.

There would be no need to have any welding on the flange/s at all.

Evan
12-09-2010, 05:49 AM
I modified the heater on mine slightly. After much searching when I first bought it (2 for $900, made one good one from the pair), I was forced to conclude that the primary fault with the heater system was that it was missing an air inlet. I know that sounds a bit ridiculous but I can only surmise that it may have been designed by a relative of Laird Lucas.

I remedied that by providing someplace for air to actually enter the system in the form of a hole in the side of the right front wing and a small hose to the fan housing. It appears that the original design circulated air from the blower to the heater core and back without actually admitting any to the cab. :D

A.K. Boomer
12-09-2010, 10:48 AM
Wow what a project, So I take it whatever bolts to the flange (bearing housing and brake backing plate ?) could not have been thrown on an RT table and have elongated slots put in for rotating?

The binding your experiencing might also be due to the variation between the soft gummy all-thread and the better flange material -- this will try to cock the tap causing a bind, what are you using for tap alignment - your drilling jig plate?



Anyways - I see your dilemma but it's really hard to make a comment without seeing all the other components --- your getting it done and that's all that matters and its going to be plenty strong enough, one last question --- why using a tap at all? that flange looks to have boo-koo space on the backside so why not just drill and run a bolt through with a nut and heavy washer on the backside?
the internal flange will provide the proper sealing surface with a gasket no?

The Artful Bodger
12-09-2010, 05:20 PM
I am not sure exactly what this part is, is it the end of the axle tube onto which bolts the spherical steering swivel joint fandangle?

My concern would be that the trouble you are having getting a good taped hole will result in a thread that will not retain the bolt reliably.

If you made the holes even bigger and put in 'helicoil'(?) inserts at least your bolts would have a good thread to lock with.

IMHO.