Photo Essay - Ba/bf Ute & Wagon Rear Axle Bearing Replacement

[PhilMeUp]

I started by removing the rear brake caliper. This is done by removing two bolts, which have a 15mm head.

On some cars, rust will have developed between the disc rotor and axle end. This can be loosened by banging a hammer on the outside of the disc rotor, near the wheel studs. Do NOT hit the hammer on the area where the brake pads go!



Assuming that you’ve remembered to leave the handbrake off, the disc rotor will then slide off. This is what is behind the disc, including the handbrake mechanism.



Behind the wheel studs and round plate are four bolts. I’ve used my Sealey AK631915 15mm Double Ring Spanner as leverage to rotate the axle.



I’ve rotated the axle so that I can access the first bolt. These four bolts will require an 8mm allen key or matching socket.



They were on quite tight, so I’ve used my extension brace to get enough leverage to loosen them. I’ve also used an extension bar so that the extension brace clears the wheel studs.



Once all four bolts were removed it was time to remove the axle, the other end of which is stuck in the diff. I used used the Sealy spanner to lever the axle out. This didn’t take much force.



Once the axle started sliding out I was able to see the condition of the diff oil. Which was not good.



A rear bearing collapsed last year so I had both bearings replaced at a taxi workshop for a cost of $260. However, the diff oil wasn’t also replaced. So, it turns out that there have been numerous metal fragments floating around amongst my diff and axle bearings for several months.



Another piece of the previous bearing cage.



The diff oil was terrible. I was feeling like a war criminal by now. Metal filings everywhere, and one very neglected diff.



Another bearing shell fragment.



The diff oil around the bearing area was full of metal fragments.



I had another BFIII wagon that I had recently bought for future taxi use, so I removed the axles from that to use in my taxi. This was late at night, and I needed to sort out a leaking axle seal for the taxi’s annual inspection.

The diff oil in the other car was the opposite of what was in the taxi.



An axle bearing from one of the taxi axles, showing some signs of wear on the roller bearings.



The handbrake backing plate just sits against the axle housing and is held in place by the four bolts were previously removed.



The outer bearing ring comes out of the axle housing. The ridge needs to be cleaned out before the axles go back in.



A close up of the axle housing ridge, including yet another metal fragment.



I’ve never replaced diff oil at home before so I resolved to start doing so on a regular basis in the future. It was time to put the axles back in, starting with putting the handbrake shoes back on.

With handbrake shoes, I find the easiest way is the have one side away from the backing plate so that I can get the other side to fit over the adjuster. Then I swivel the handbrake shoes back against the backing plate.



There is a clip that holds the handbrake shoes against the backing plate. This is important - if the clip is bent outward then the handbrake shoes can move around inside the disc rotor, resulting in some odd noises at slow speed.



Being late at night, I wasn’t able to replace the bearings at home so I used the axles from the other car.

[PhilMeUp]

It was too difficult to get the retaining plate bolts back in, so eventually I figured out that the easiest way was to have the bolt poking through the retaining plate, and then push the whole lot back into the diff housing. This meant levering the axle up and down a bit to get the diff end to go into the diff.



I managed to get all four bolts back in and tightened them with a ratchet and the 8mm allen key socket that I used to remove the bolts originally.



The DBA4000 disc rotor that I have doesn’t allow me to adjust the handbrake whilst the disc is on the car, so it’s a game of trial and error to adjust the handbrake before I put the disc back on. Adjust it out too much and the disc won’t go back on over the handbrake shoes. Adjust it not enough and there’s too much movement in the handbrake lever inside the car.



There is an adjuster hole but it needs to be further outward on the disc.



Moving to the passenger side of the car, you can see the grime that has built up over time. This is because of a blown axle seal, and there was similar grime on the inside of the back wheel.



This is what is on the end of each axle. A retaining collar, a bearing, a seal and then the retaining plate to hold the axle in place. When fitting this stuff it is obviously essential that everything goes in the correct order.



Once the axle is back in place then it’s easy enough to poke a flat blade screwdriver through and hit it with a mallet or hammer to make sure that the handbrake clip is pushed back as far as possible.



This job didn’t require a lot of tools:
- The usual cordless drill
- Some brake parts cleaner
- Flat blade screwdriver
- Extension brace
- Extension bar and 8mm allen key socket
- The extra long 15mm spanner that I’m using a lot these days
- My usual 15mm ratchet spanner
- A rubber mallet
- A brake pad spreader, to make it easier to put the rear callipers back on
- Some soft drink



I bought this Disc Brake Pad Spreader from Radum some time ago and it’s proven to be extremely useful when doing anything to do with brakes. It’s relatively small and fits in the toolbox, and pushes brake pistons back in easily.

Here it is being used on a twin piston front caliper. I’ve positioned the spreader partially over the two pistons to push them both back in at the same time.

This spreader also doesn’t have the usual plastic dial that other spreaders have, so it doesn’t break.

Radum: http://www.radum.com.au
Stock Number: RDM-BM94-4062
Current Price: $27.00 (including GST)
Link: http://radum.com.au/catalog/product_info.php?products_id=8685



On the utes and wagons, the diff is offset to one side. This means that one axle is longer than the other.



When I put the retaining plate bolts back in I used a torque wrench to tighten them up to the specified 45Nm.



Whenever I have disc rotors off a Falcon these days I am usually getting the drill and wire brush out to ensure that the relevant surfaces are clear of corrosion. This is the ensure that the disc rotors sit up against their respective backing properly (ie rust can push the discs slightly out of alignment, creating brake shudder).



The inside of a disc rotor once it’s been cleaned with the drill and wire brush.



With this particular disc rotor, there was a hole in just the right place for adjusting the handbrake with a flat blade screwdriver. For this one, use a flat blade screwdriver to push the adjuster ring to the left in order to force the handbrake shoes outward.



This photo shows everything back in place on the donor car, ready for the wheel to go back on. I put the donor car’s axles in the taxi and then got new bearings put on the taxi axles (which then went back into the donor car few days later).



When adjusting the handbrake, I reach behind and pull the actuating lever to see how much freeplay there is left. That tells me whether I need to keep rotating the adjuster ring from the other side.



I’m loving the discs on the donor car with the way that they have the holes in the right place to allow me to adjust the handbrake with the discs on. This is as high as I could pull the handbrake inside the car.



The utes and wagons use the same axles, so I recently bought a stuffed ute diff so that I could have a spare set of rear axles. I bought a bearing separator kit today and tried to use it tonight to remove the bearings with my hydraulic press. This did not work, and I’ll need to buy a larger bearing spreader for this job. I’m hoping to come up with a way of using the press to push the bearings off the axle.

How do taxi mechanics remove the bearings? Rather harshly. They use an angle grinder to grind away the retainer ring, and then use a hammer and chisel to smash the bearing cage to pieces. Rough, but it works. But I’m trying to come up with a way of using the press so that I make almost no noise doing this, because I tend to work on my car very late at night.

If you want to do this job yourself as cheaply as possible then remove the axles, cut and bash the bearing off and then get somewhere with a hydraulic press to press on the new bearings for you (that you will have already bought from somewhere).

In recent times when I’ve had to do something that involves noise I’ve gone to a nearby shopping centre carpark and done whatever is required there. To get the rear discs off the donor car, I went to a nearby shopping centre, jacked up the back of the car, removed the back wheels, belted the discs with a hammer, put it all back together and went home. Very impractical.



Here’s an iPhone photo of new bearings being pushed onto one of the axles at a taxi workshop. The mechanic applied 10 ton of force onto each axle bearing, so my 20 ton press should be able to do this easily enough.



Another photo of the new bearings being pushed on to one of the axles.

[PhilMeUp]

A few days after I did this job I drained and replaced the diff oil on both taxis (ie girlfriend’s and mine). The oil from Deb’s diff also looked bad, so I’m going to start replacing the diff oil and axle bearings myself on a regular basis. I’ll start with doing it every six months on each car, and see how the diff oil looks each time. Replacing the bearings so often will be a bit excessive and wasteful, but will hopefully ensure that a bearing doesn’t collapse and fill the diff with metal particles.

Draining the diff oil is easy enough, but make sure that you are able to remove the filler plug before draining the oil. The filler plug requires a 10mm allen key. I managed to get the fill plug out on each taxi with a normal 10mm allen key, but I’ve ordered a Bondhus Extra Long 10mm Allen Key for future use. The Bondhus part number is 16076 and it’s 213mm long.

Choice of bearings: I asked at two different taxi workshops and they both were adamant with the same answer. Only use Timken 4827 Wheel Bearing Kits, as they last the longest. There are plenty of other choices which have been tried but apparently the Timken ones last the longest.

A search on eBay shows them to be currently available for $49.50 including postage for just one side, or $94.50 including postage for two sets (ie both sides). Check with your local bearing supplier for pricing and availability (eg CBC Bearings, SKF, etc).

And, as mentioned before, make sure you pay attention to the order in which everything goes back on the axle, including the retaining plate.

I’m going to figure out a way of pressing the old bearings off with a hydraulic press, and will update this once I’ve done so.

Torque settings from Ford, including the 45Nm for the retainer plate bolts:



This isn’t on their web site - Radum have a 20 ton hydraulic press for $190. Not bad. Stock number is RDM-SX0406.






Part 2:

Tonight I had another go at pressing the bearings off the axle, with some success.

I bought a bigger bearing separator - a 75mm to 105mm one. I bought mine from Radum (stock number VT01208C) for $26.00. This fitted nicely behind the bearing cage, so I was able to proceed with pressing it off.



I got a couple of iron plates out of the box of stuff that came with the press and managed to set everything up so that the press could push downward on the axle while the bearing separator kept the bearing in place (ie forcing the bearing and collar off their mounting area on the axle). The iron plates were 95mm high, but that turned out to not quite be enough…



I kept pumping on the bottle jack at the top but didn’t realise that because the iron plates weren’t tall enough the whole axle was soon pushing downward on the cross beam. I’ve bent my new toy! Pretty miffed, but I’ll remove the cross beam in the future and take it to a metal fabrication shop with a big press that can press it back into shape. Until then I’ll unbolt the bottom off the press and flip the cross beam over the other way up.



The collar and bearing did get pushed upward enough to make them loose enough to remove. Mission accomplished. You can also see that two of the wheel studs got pushed out by the cross beam. I banged them back in with a hammer easily enough.



Once I had the seal, bearing and collar off I made sure to learn which way the retaining plate goes. If you’re ever doing something for the first time and you’re unsure of something then get the camera or phone and take photos. Sometimes those photos come in handy later on when you’re trying to remember which way something is meant to reassemble. On this axle the indents in the retaining plate were facing outward, toward the wheel studs.



I finally had the axle apart. The ABS rotor came off the axle easily enough by moving it at opposite sides with my hands (ie no force, so that I didn’t risk bending it).



This axle had a lot of grime on it, so I decided to knock out the wheel studs with a hammer and clean everything up for future use.



The bare axle, once the ABS rotor, axle seal, bearing and collar were all removed.



The outer side was very uneven. I don’t have a workbench and vice, so the press held the the axle in place whilst I got busy with the usual drill and wire brush. The area got brushed back to bare metal. I applied minimal pressure to the axle with the press to ensure that the axle would not get bent, and had the axle on the iron plates instead of the gap in the middle of the cross beam.



Then I put the axle studs back by banging each one in with a hammer. I had already cleaned the threads on each stud with the drill and wire brush to ensure that the wheel nuts go on easily when I use this axle in the future.



Then I put the ABS rotor back on after cleaning it. Twice, after I didn’t realise to line the holes up the first time. Don’t forget this - the holes need to line up so that when the axle goes back in you can insert the retaining plate bolts. If the holes don’t line up then the new bearing will have to be removed and the whole process started again (ie wasting the new bearing set).

I wasted half an aerosol can of brake cleaner on this, which is expensive (especially for just the one axle). For the other axle I’ll put a bit of petrol in an oil drain pan and use a toothbrush to remove the grime.



The retaining plate was then put back on. This will sit there loosely until I buy some Timken 4827 bearings and press them on. But I won’t be doing that until I need to use the axle. Until then I’m going to put a plastic bag over each axle end and seal it on with a zip tie to keep it clean and prevent corrosion.



As mentioned earlier, to get rear axle bearings replaced at a taxi workshop costs me $260 each time (for both sides). I haven’t gotten local pricing for the Timken bearings yet, but even if I pay $95 for them on eBay then I’m still going to save some money. Although, instead of waiting until a bearing wears out or collapses, I’m going to start doing this at least every six months on each taxi as a preventative measure. I’ll also be changing the diff oil regularly to ensure that the bearings and diff are not worn prematurely by contaminated oil.

I had been looking for a set of suitable secondhand axles for a while. I found an advert on Gumtree for a worn out BA XR6 ute diff, so quickly bought that for $100. I’ve now also got the complete AU3 diff, which cost me $200 (ie another pair of axles there). Pricing from wreckers ranged from $200 to $275 for each axle, and I couldn’t justify spending that much. By having a spare set of axles I can have them prepared and ready to install before touching the car. As you can see from the previous photos, removing the axles is a very easy job, so swapping them should take well under an hour.

The bonus is that you get to adjust the handbrake at the same time.

For someone who wants to change their rear axle bearings as cheaply as possible, without a press at home, then:
- Remove the axles.
- Use an angle grinder to cut the collar off.
- Smash the bearing cage with a hammer and chisel.
- The seal will then slide off.
- Take the axles to somewhere with a press and get them to press the new bearings on.
- Reinstall the axles, rear brake caliper, back wheels, etc.

[PhilMeUp]

Tonight I wanted to get the other axle ready for future use. I figured that after learning some lessons last night, tonight would be routine. Wrong.

The first job was to remove the other axle from the diff that I bought. I removed the four retaining plate bolts, but no matter what I did the axle would not slide out. I tried various things with a hammer and crowbar but the axle would not move. This had me stumped for a while, until I decided to put an old disc rotor on and yank that back and forth.



It took a while, but yanking the disc rotor back and forth eventually got the axle to slide out.



After stuffing up and bending the cross beam previously I was more attentive to the lower area of the hydraulic press tonight. I put some spaces on top of the plates to ensure that there was enough room between the axle wheel studs and the cross beam. I’ll need to buy some proper arbor plates for future use.



This axle continued to be unco-operative. No matter how much I pushed the axle downward in the press, the collar would not move. Instead, the bearing cage collapsed to the point where I had to try something else.



Stuff it, I’ll try cutting the collar off with an angle grinder. But I wasn’t going to wake the neighbourhood at 2:30am, so put everything required into the car and drove to a nearby shopping centre carpark.



Although the battery was fully charged, the cordless grinder didn’t get very far. This collar was really putting up a fight.



After going back home, getting two more batteries and running them flat, I gave up on using the cordless grinder to cut the collar off. Time to try just pressing the collar off on its own.



This worked, and the collar eventually came loose. Victory. The inner ring from the bearing cage was still there, so that was the next thing to remove.



I put the bearing separator under the bearing ring, which then came loose with minimal force from the press.



More than an hour and a half after I started trying to remove the axle from the diff, I finally had an axle with the seal, bearing and collar removed. This was taking way too long.



After wasting an expensive can of aerosol brake cleaner previously, tonight I tried a cheaper method of cleaning the axle. I found some kerosene and an old ice cream container, so figured I’d see if that would clean off the grime.



I had knocked out the wheel studs with a hammer and was cleaning the threads on each wheel stud with the drill and wire brush when I noticed a damaged thread on one wheel stud. Although it’s fairly minor, I don’t want to risk stripping the threads in the new wheel nuts that I recently bought.



I didn’t realise until tonight that the front and rear wheel studs are different. I have plenty of spare front studs, so figured that I’d grab out of those for the rear axle. But they are different, and a front stud won’t even stay in the rear axle because of the different diameter in the collar. I also learned to stop banging them out so aggressively with a hammer, like I’ve been doing.



I had a go at cleaning the ABS ring, the retaining plate and wheel end of the axle with the kerosene and a toothbrush. Everything is now clean and ready to have new bearings pressed on to the axle.



Lesson learned: Don’t underestimate the stubbornness of the collar. Either cut the thing off with an angle grinder or use the press to just remove the collar on its own first. It’s a bit quicker to use an angle grinder, due to the time that it takes to set up the press. Moving the cross beam to the bottom of the press, setting up the plates and spacers and then pressing the collar off takes a bit of time. However, with the right set of arbor plates (ie steel plates made especially for stuff like this) then pressing the collar and bearing off would take very little time.

[genuine honest person]

great work mate ,have taken in a lot of info.this will help me a lot mate

[FiftyOne]

Epic thread

[PhilMeUp]

After spending a bunch of time messing around with learning all this stuff it was time to put it to actual use. I was trying to remove one of the back wheels on my girlfriend’s taxi last week and one of the rear wheel studs snapped off. I knew that it was going to be relatively time consuming to fix, but this was what I had been learning about recently.

I used the press to remove the collar and bearing, and then levered the ABS rotor off with a crowbar.



I also used the press to make sure that the new wheel stud was pushed in properly. I would normally use a hammer initially, and then tighten the wheel nut extra tight later on to pull the wheel stud through, but this way I knew it was done early on and pressed in as far as it could go.



This is what comes in the Timkin 2985 bearing kit that I used. There’s the seal, the bearing and the collar. I previously mentioned a Timkin 4827 kit - I don’t yet know what the difference is (if any).



I had trouble getting the ABS rotor to slide back into place on the axle, so I heated up the inner ring with a propane torch. It still wouldn’t go on, so I ended up pressing it on with the press.



Finally, it was time to do an actual job with the press and push the bearing and collar into place. I put a metal spacer on top to ensure that force was spread evenly on the hub, and that nothing would get dented or damaged.



A couple of months ago I removed some axles from a wagon and took them to the workshop so that I could see how they do it. They were using a 50 ton press with a pressure gauge, and I asked the mechanic how much pressure to use. He said to go to 10 to 15 ton, so I figured I’d go roughly half way with 12 ton. The gauge on the new press was extremely useful, and meant that a novice like me could do this without applying too little or too much pressure.



This side-on photo shows why I had to go through all this just to replace one broken wheel stud. To remove the broken stud the ABS rotor must come off. To remove the ABS rotor the seal, bearing and collar must come off. I had tried to press the bearing off so that I could use it again, but the bearing cage bent out of shape as soon as I applied force with the press.



Here you can see where the ABS sensor is, and how it is positioned over where the ABS rotor will go. There is the clip that holds the handbrake shoes against the backing plate - when that clip is bent outward the handbrake shoes can move around and make some odd noises. I’ve also made sure that I’ve cleaned the ridge inside the axle tube before I put the axle back in. There was also a bunch of grime around the axle tube area from a previous axle seal leak, so I put some kerosene on a rag and wiped that around to get the grime off.



I then took the car for a test drive and was pleased to find no strange or alarming noises. I got it right. This test drive was also to warm up the diff oil, which I changed when I got back. Success!

[PhilMeUp]

Last night it was time to replace the rear axle bearings on my taxi. They started making noise on the weekend, so I wanted to get that fixed promptly.

I removed the collar from the first axle and then tried attacking the bearing cage with some pliers. It took some frustration and cursing, but I finally managed to remove the bearing cage and roller bearings. This was time consuming and cumbersome, but now that I could see the axle shaft I could make sure that I didn’t over-tighten the bearing separator and scratch the axle when I removed the inner ring.



I wore disposable rubber gloves when removing each axle from the car, and then wiped up and down the axle shaft with a rag to get the diff oil off it. This minimised putting oil on everything else that I handled.



I made sure that I had plenty of spacers in place so that I didn’t repeat my previous stuff-up of pushing the axle through and bending the cross beam on the press. I also put a rag under the axle to minimise the noise - when the collar slides loose the axle drops down suddenly and makes a bunch of noise on the cross beam - it was after midnight, so I was trying to do this quietly.



Pressing the collar off is a bit intense. Pressure builds up as the press is pumped and then the collar just snaps loose. It makes a loud popping noise when this happens, followed by a bunch more noise when the axle drops down, falls over and sends itself and spacers flying everywhere. I’m going to stick with removing bearings during the daytime - it’s too frustrating trying to do this quietly late at night.



One of my failed attempts at removing the bearing cage without making noise. By now I was starting to understand why mechanics put the axle in a vice and then just destroy the bearing with a hammer and chisel.



Removing the bearing cage quietly really isn’t the way to do this...



Stuff it - just put the axle back in the press and use that to push the bearing off. The trick is to get the separator in the right place, and tight enough to get behind the bearing inner ring but not so tight that it’s scraping against the axle.



You can see in this photo the marks left on the axle when someone else has previously used a hammer and chisel to smash the bearing off. My techniques have been much slower than using a hammer and chisel, but they also mean not damaging the axle any further.

[PhilMeUp]

My attempts at using the press to remove the bearing collar had been clumsy. It requires a huge amount of force to remove the collar, and I don’t have the right metal offcuts to hold the axle up with the bearing separator whilst pushing the axle downward with the press.

Why not just cut the collar off, like everyone else does? Because I had been trying to do the entire job in such a way that I could do it late at night (ie no noise, meaning no power tools).

I’ve got several spare sets of axles these days, which means that I can prepare them for future use in the daytime and then press new bearings on at night.

Time to have a go at cutting the collars off.

I bought two cutting discs - a 100mm one and a 115mm one. It turned out that the 115mm disc was too big to cut the collar without also cutting into the ABS rotor, so I ended up using the 100mm disc instead.



The cutting disc cut through the collar easily enough.



I cut through as far as I could but the collar wouldn’t break loose, so I made a second cut.



This photo shows just how close the 100mm disc gets to the ABS rotor, and why the 115mm disc is too big. All it takes is one brief contact between the cutting disc and the ABS rotor, and the ABS rotor becomes useless. The cutting disc also doesn’t quite cut through the entire bearing cage.



I bought a pair of Trojan 200mm bolt cutters from Bunnings sometime ago. At $9.98 they were cheap enough to put aside for possible future use. It turned out that they are very good for cutting off the outer bearing cage.



I was able to dismantle the bearing cage, piece by piece.



That left the bearing inner ring and the collar.



As I had been unable to remove the collar so far, it was time to try a hammer and chisel.



This broke the collar open and I was able to slide it away. There was a mark left on the axle where I had cut through too far.



Then I used the press to remove the inner bearing ring. This is still very frustrating to get set up - it’s difficult to get everything to stay balanced before getting the press pushing down on top of the axle. I’ll need to get some metal blocks made up that are at least twice as thick (ie less inclined to fall over). My previous attempts to press the collar off had broken the bolts in the bearing separator. I bought some threaded rod to replace them, but that bent easily as well.



The inner ring doesn’t require much pressure to remove. The problem is getting everything lined up and balanced first.



I eventually ended up with two axles ready for new bearings to be pressed on.



Before pressing the new bearings on I cleaned up the end plate and wheel studs with a drill and wire brush. I use a Josco 100mm Wheel Wire Brush.



Once I had removed any rust the the axles were ready for new bearings to be pressed on.



The two axles, ready to go into the car.

[PhilMeUp]

I found a cheap Dremel secondhand so bought it to see if it would be any better for cutting off the collars. I used a Dremel 1-1/4" Fiberglass Reinforced Cut-off Wheel that came with the Dremel.



Although the Dremel was working fairly hard, the thin cutting disc cut through the collar quite easily. I was barely half way through when the collar cracked.



This was fairly easy - the collar slid away.



I then tried cutting through the bearing cage. The Dremel got through this easily enough.



Once I cut through the outer rings, I was able to lever them off with a screwdriver.



This left the inner ring to remove.



I tried cutting through and removing the axle seal. Before doing this, I cleaned away the metal filings.



The last remaining part of the old bearing was the inner bearing ring. I tried cutting through this with the Dremel, but also nicked the end of the axle.



However, the Dremel cut through the ring quite easily.



Once I cut through the inner ring and removed it, I could see the mark where I had cut through too far. However, the axe is still useable. You can also see the markings where previous mechanics have used a hammer and chisel to smash off previous old bearings.



The ring slid off before I had cut entirely through it. This would have been because of the heat generated by the cutting disc.



However, the Dremel cutting disc did wear down quite rapidly. These discs are cheap enough - less than $10 for a pack of 5.



As mentioned earlier, the collar cracked shortly after I started cutting through it.



Conclusions so far:

- Using a press to remove the collar is difficult because of the amount of force required. Pushing the axle downward that hard makes it very hard to balance with a bearing separator and metal plates.
- Cutting the collar off with an angle grinder and cutting disc is suitable, although that requires a lot of concentration and balance to ensure that the ABS rotor doesn’t get touched. I found that putting the axle in the press (I don’t have a bench and vice) and holding the angle grinder against my chest helped me to be precise with the grinder.

- The Dremel was working hard to cut through the collar, but it did get it done quickly and easily. I would probably do it this way in future, even if it was just to ensure that I didn’t damage an ABS rotor with an angle grinder (I’m clumsy).

- Removing the inner bearing shell is best done with the press, although it could be done with a Dremel and some precise co-ordination.

- I used a Dremel 3000 this time, but bought a secondhand Dremel 4000 since doing this. The 4000 is more powerful, and should be able to cut through the collars easily.