Tree Stump Grinders

Today we are looking at something a bit different, the Dipperfox stump crusher 600 or stump grinder. Recently we looked at the Dipperfox stump crusher 850 pro, however, DipperFox is now introducing a smaller stump crusher known as the Dipperfox 600.

The Dipperfox 850 pro is a great stump crusher, however, many users, do not have a large enough power unit to drive a stump crusher of this size. Hence why I believe the stump crusher will be highly successful.

 

You Can Find Smaller Stump Grinders Here

 

 

 

The Dipperfox Stump Crusher 600

Having run traditional stump grinders since 2004, I know the limitations and the time it takes to grind out a large tree stump. I’m currently using a Predator 38 RX radio remote machine which is great for getting into private gardens with limited access. However, something like the stump crusher 600 could potentially change stump grinding for the future. I appreciate that getting into domestic gardens in the UK will always be an issue and I guess I will always have to run something like the Predator 38 stump grinder. However, I really like the idea of having a stump grinder that can remove stomps quickly and doesn’t need to be guarded up.

 

Here You Can See The Dipperfox Stump Crusher 600 Being Used On A Yanmar 5.5 Ton Excavator

 

 

The Dipperfox stump crusher 600 is 60 cm in diameter. In my experience, this is more than wide enough for most tree stumps. However, the Dipperfox 600 can be moved around easily. So the stump cutter can actually cope with any size stump. I know how long it takes to grind a tree stump with a traditional stump grinder. The Dipperfox Stump Crusher 600 really make short work of tree stumps. The grinding depth of the stump crusher 600 is up to 700 mm. Which is much deeper than a traditional stump grinder that would probably go to around 45 cm.

What Are the Advantages Of The Dipperfox Stump Crusher 600?

Many people may think that if you have an excavator on-site, why not just dig the tree stump out? The problem with digging a large tree stump out is the fact that it actually takes quite a lot of work to dig a large tree stump out. The other major problem is the fact that; what do you do with the tree stump once it is dug out? It costs money to dispose of a large tree stump. This is where the stump crusher 600 saves time and money. There is no levelling to be carried out after the stump has been crushed. All the chippings can go back into the ground.

The manufacturers claim that the average tree stump takes 20 seconds, this is pretty remarkable. Even if it took a few minutes, it would still be impressive!

Another great plus point is the fact that the debris isn’t thrown everywhere, so there is no need to guard up. The maximum speed of the stump crusher is only 60 revolutions per minute.

The Dipperfox Stump crusher 600 can be used below the ground level.

To Conclude

I really like the idea of the Dipperfox Stump Crusher 600, it really seems like a quick time-saving design. It would be good to see the stump crusher in live-action, so far I have only seen the stump crusher on video. I hope to see a live demonstration of the stump crusher 600 working very soon. It’s not a cheap machine at around €19,000, but I can see that it could certainly be a time-saving machine the great work rate.

For more information, you can visit the Dipperfox website here.

Specification

 

 

 

Here is my review of the Predator 38 RX EFI radio remote stump grinder.

I have been using Predator stump grinders for the past four years, prior to this I was using American Carlton stump grinders. One of the biggest reasons for changing to a Predator 38 stump grinder was the fact that the Predator has the ability to be able to fit through narrow gateways. This is a huge benefit for small English gardens!

My first Predator was a Predator 28 RX radio remote diesel machine which had its fair share of problems. I then went to using a petrol carburettor (Predator 38 RX) machine for a short period which worked absolutely fine, although quite heavy on fuel. I now have a Predator 38 RX EFI radio remote stump grinder which is so far going really well.

 

You Can See My Video On The Predator 28 and 38 Stump Grinders Here

 

Trouble-Free Stump Grinding

At the time of creating the video I had about 200 hours on the clock, I now have about 270 hours which has been trouble-free. This is after approximately six months of use.

You Can See My Video Review Of The Predator 38 RX EFI Radio Remote Stump Grinder Below

 

 

Narrow Stump Grinder

One of the best features about the Predator 38 RX EFI is the fact that it is as far as I know the narrowest machine on the market in its class. The Predator narrows down to just 26 inches (66 cm) which means it will fit through most garden gates. I believe the next machine up is about 3 inches wider in size, which is not a huge amount. However, I know that I am often up to my limits when it comes to getting through narrow gates, this is something that the Predator 38 EFI does well.

Just one thing regarding narrowing the tracks; bringing the tracks in is purely for getting in narrow gateways. Great care needs to be taken when manoeuvring machine as it is very unstable when the tracks are at the narrowest point. This is fine for going to gateways, just take care as any small divot’s in the ground can quickly make the machine catch a gatepost or other obstacle.

As I mentioned at the start of the post, I used Carlton American stump grinders for many years, they are well-built machines, however, it’s that width problem again! My Carlton 4012 stump grinder had dual wheels which could be removed for narrow access jobs, this helped, however, it was a fairly painful exercise and time-consuming. It is far easier to flick a switch on the radio remote and watch the tracks narrow up.

Kohler 38 EFI Engine

I never expected to be purchasing a petrol stump grinder, however, I have and I’m very pleased with the result.

To be fair, I would prefer to have a diesel engine stump grinder. But after having so many problems with the Lombardini engine on my first Predator. I decided to go with the petrol engine version. I was using a petrol carburettor engine model for a few months which worked absolutely fine, although it was quite heavy on fuel.

The Kohler EFI petrol engine is a great improvement on the carburettor model. Although they are almost the same engine the EFI makes a huge difference not only in the economy but also low down torque. The carburettor was a bit slow when you need more fuel, however, the EFI engine reacts almost instantly. Definitely a great improvement over the carburettor Kohler engine.

The Kohler engine also offers more power than the diesel version. The Kohler EFI engine develops 38 hp whereas the Lombardini diesel engine develops 28 hp. To be fair the actual performance of the Lombardini engine on my previous machine was absolutely fine. However, reliability was not! I do not hear many good things about Lombardini engines.

Multi-Tip Cutting Wheel

The Predator 38 EFI comes with a multi-tip cutting wheel complete with six teeth. Only two of the teeth actually carry out the cutting, the other four teeth are for clearance. Normally, I only replace the two cutting teeth regularly. For the other, for clearance teeth, I normally replace these as and when they are worn with used cutting teeth.

The performance of the Multi-Tip cutting head is very good and replacing the teeth is also very quick and easy. The only issues I have had with the Multi-Tip cutting head is the fact that the bolts that secure the teeth can sometimes shear off. I have written a post about my experience with the Multi-Tip cutting head, which you can see here.

After trying finger teeth and green teeth on previous machines, I do prefer the Multi-Tip cutting system. Finger teeth were continually breaking on a daily basis, it’s not a five minute job replacing finger teeth!

 

 

Would I Recommend The Predator 38 RX EFI?

 

Yes, I definitely would recommend the Predator 38 RX EFI. I would avoid the diesel models as my experience has not been good. The greatest plus point of the Predator stump grinder is being able to get into gardens with limited access. The grinding capacity is also excellent.

 

One thing I would like to see is a slightly better build quality. On the other hand, I guess the manufacturer is trying to keep the weight to a minimum. I believe this is one of the reasons I had so many problems as my diesel Predator stump grinder suffered from vibration issues.

 

Overall, if you’re looking for a stump grinder with a good capacity for work, I would go for a Predator 38 RX EFI radio remote stump grinder.

Multi-Tip or green teeth stump grinder cutting wheel? What is your experience, I would like to find out more?

I have owned and used several different Predator stump grinders, my current Predator being a petrol radio remote Predator 38 RX, which I’m more than happy with.

My Predator is fitted with a Multi-Tip cutting wheel which in general I really like. Over the years I have used traditional finger teeth and also green teeth, the cutting efficiency is very good on the Multi-Tip wheel. Another great advantage of the Multi-Tip cutting wheel is the fact that the teeth are extremely quick to change. I guess it takes about 3 to 4 minutes to change the two lead cutting teeth.

 

There are six identical teeth on the cutting wheel, but only two teeth actually cut, the other four teeth are just for clearance. The teeth work in opposite pairs so there are actually three different positions on the cutting well, obviously, the forward-positioned teeth are the cutting teeth.

 

If You’re Looking For A Stump Grinding Service in East Anglia, Please Go Here

 

However, one problem that I have continually encountered is bolts shearing off, which is annoying and time-consuming. On average, I would say I lose 30 minutes each time a bolt shears off. Now I know I said a couple of paragraphs back that it takes 3 to 4 minutes to change to teeth. However, when a bolt shears off, you need to find the keeper block, the tooth and remove the broken bolt from the threaded insert, this takes time. Plus you need to go and find your tools to replace the bolt.

You Can See My Video On The Multi-Tip Cutting Wheel Below

 

With my present stump grinder, it had carried out about 15 hours work when the first bolt sheared. Once the first bolt shears, many more broken bolts will follow! I can actually have days where I shear 3 to 4 bolts or none at all!

My question is; would I be better off with a green tooth cutting wheel. In the past I tried using the green teeth cutting system on a Carlton machine, however, the pockets almost wore faster and the teeth! This became an expensive process due to the fact I was and regularly replace the pockets. I believe that this could be rectified by using larger green teeth.

 

You Can See My Review of the Predator 38 RX Stump Grinder Here

 

I believe that one of the biggest problems is with the Multi-Tip cutting wheel is that the wheel is not hard enough. Predator gave me a new Multi-Tip wheel a few years back due to the fact they had some wheels that were not hardened correctly.

I would be interested to hear what your experience is on the Multi-Tip cutting wheel and your experience of using green teeth?

Please comment below.

Review Of The Predator 28 And 38 Radio Remote Stump Grinder

 

Here is my review of the Predator 28 and 38 radio remote stump grinder. This is a review of the Predator stump grinder that I own and have personal experience with, having operated for many hours! I have created a video review of the two Predator stump grinders below.

I haven’t created this review to be negative, it’s just a genuine review of the Predator 28 and 38 radio remote stump grinder. I would be very interested in hearing about other people’s experience, good and bad.

First of all, I would like to give a positive review for the Predator 38 stump grinder, I have had the Predator 38 tree stump grinder on hire from Ben Burgess several times and have probably clocked up around a hundred hours of use with this machine. I believe that the Predator 38 and 28 stump grinders are the narrowest machines in their class on the market, both narrow down to 26 inches (66 cm) which is fantastic, if you have used the traditional pedestrian stump grinders you will understand why it is so useful to get through narrow gateways and not have to struggle with a pedestrian machine.

I would also like to mention that I have been looked after extremely well by Ben Burgess, who are Predator dealers if you’re looking to buy or hire a stump grinder I would definitely recommend Ben Burgess. Or if you’re looking for a second-hand stump grinder it may be well worth checking out eBay.

 

 

You Can See My Video Review below

 

Predator 28 Radio Remote Stump Grinder

I purchased my Predator 28 radio remote machine in October 2016, I have to say I have had my fair share of problems which I will talk about more in this review post. In the three years of owning my Predator, I have probably called them 150 to 200 times in under three years. Over the past 30 months, I have had approximately 40 breakdowns that have stopped me working! It is good to point out that the Predator 38 has given me absolutely no problems at all and in my experience, it’s a good machine to purchase. The biggest plus point is that the Predator 38 has a fair amount of power for a machine of this size and can cope with any sized tree stump.

On the downside, it does use a lot of petrol, if you’re using the Predator 38 continually for a day it will use around £100 worth of fuel, on my Predator 28 diesel machine I will probably use about £30 worth of red diesel. However, probably on an average day, I will use around £35 worth of fuel with the petrol machine. You can see another post I wrote about the fuel consumption of the Predator 38 here.

I purchased my Predator 28 radio remote diesel stump grinder back in October 2016, prior to this I had been using a Carlton Lombardini diesel radio remote 4012 machine and also a petrol SP2000 pedestrian machine.

The biggest reason for me purchasing the Predator 28 was due to the compactness of the machine, which has proved to be a very useful feature time and time again.

I went for the radio remote machine with a Lombardini diesel engine, the machine that Predator demonstrated to me was a manual machine which I had no intention of buying, but it was the only one they had available for a demonstration. If you are buying a stump grinder and there is a radio remote option, I would definitely go for it, it is so much easier to use and saves a lot of time.

Exhaust Issues

I hadn’t carried out many hours work when probably at around 10 hours work the jubilee clip that assists holding the baffles on the exhaust broke, I did kind of expect this to happen as jubilee clips are certainly not strong enough for holding anything like an exhaust in place. Also, in my experience of Lombardini engines, it’s very rare to see them with the exhaust in the right place after they have been used on a stump grinder. I have experienced this with my Carlton machine and the Predator.

After the jubilee clips broke that was quickly followed by the baffle plate vibrating loose and literally tearing the metal on the exhaust. I understand that it is much better not to have anything attached to the exhaust whatsoever otherwise this only causes issues. I believe I am on my fourth exhaust and will be on my fifth exhaust in about a weeks time.

Have you experienced problems with your Lombardini exhaust lasting? I have certainly had issues over the years with keeping an exhaust in one-piece!

Multi-Tip Cutting Wheel

The Predator comes with Predators own multi-tip cutting wheel, the wheel consists of six teeth, two of which carry out the main grinding and the other four are clearance teeth. All the teeth are identical and changing the teeth is exceptionally simple, just one bolt to hold the teeth in place, the teeth can literally be changed in a few minutes.

In my experience, I’m really pleased with the performance and the ease of changing teeth. I’ve used the old-fashioned finger teeth which are very time consuming to change and break regularly in my experience and I have also tried green teeth, without much success.

 

Unfortunately, after about 30 hours of work, I started to break lots of bolts that hold the teeth in place, on average I was breaking three per day. I purchased a new multi-tip cutting wheel which again solved the problem, however, after 30 hours the problems started again. Predator did tell me that they had had a few issues with some soft metal wheels that had not been hardened properly. In fairness to Predator, they gave me a new cutting wheel free of charge. The only problem being that because I was breaking so many bolts, it wasn’t always possible to find the teeth and the blocks that hold the teeth in, which obviously incurs more cost in replacing them.

Apart from this issue, the multi-tip cutting system has been the best cutting system that I have used.

What is your experience with stump grinder cutting wheels and which system do you prefer?

Incidentally, I have just had the main cutter head bearing replaced after approximately 800+ hours which I reckon is pretty good as the cutter head takes a beating in the best possible way. I always give one or two pumps of grease before carrying out a days work. Apparently, on this machine, you can over grease and push the seals out if you’re not careful, hence the one or two pumps of grease.

Belts To The Cutter Head

The belts to the cutter head are something that in my experience need quite a bit of attention, I fully understand and appreciate that these belts are under considerable load most of the time. Obviously, new belts stretch, so after around six or seven hours it is important to tighten up the belts.

This is a reasonably straightforward process, originally I used to take the five bolts that hold the rubber guard off but now I have cut through the rubber guard, so I simply have to take the metal belt guard off to access the cutter head belts.

 

To tighten the belts release the four bolts that hold the cutter head on and then undo the nut that releases the cam to tighten the belts. The process can be a little bit awkward when you first carry it out, but it does get easier once you have done the process a few times. The adjuster is a square-headed bolt, I actually have a socket that fits this on a large lever that makes the job much easier.

I’ve actually had the three cutter head belts last up to 300 hours on the other end of the scale I have had the belts last three hours, I have no idea why, but this has happened, unfortunately. I also find that I am tightening these belts a bit more often than I would actually like to, I’m not sure if this is due to vibration from the diesel engine as when I had the petrol machine on hire I didn’t have to make any adjustments at all.

One of the issues that I’ve had with the cutter head adjustment is a spacer/bolt that seems to break regularly, it is a known problem.

 

As the video shows, I have actually had my bolts changed around as the threads were getting a bit worn, to my mind the new way is much better.

The Electric Clutch

Both the predator 28 stump grinder and 38 have an electric clutch to engage the cutter head, I always engage the cutter head on tick over as I don’t like to see the cutter head snatching in as I feel this shortens the life of the electric clutch. However, unfortunately on the petrol machine, you have to have a few revs to engage the clutch, otherwise, the machine will simply stall. I am told that with the new petrol model with the Kohler EFI engine you can engage the electric clutch on tick over which is great news.

I have had no issues with the electric clutch so far.

Predator 28 Stump Grinder Engine Drive Belts

In general, the engine Drive belts have lasted quite well, there are three belts from the engine then go onto a pulley system and then three more belts that go to the cutter head.

Unfortunately, my first Predator 28 stump grinder engine Drive belts broke at 19 hours, however, the next set of three belts lasted well over 500 hours and the present set of belts have done about 300 hours of work.

To adjust these belts is very straightforward, simply loosen four large bolts on the base of the machine and to the rear of the machine, there is a thread where you simply turn the bolt to tighten the belts, very straightforward indeed.

Lombardini Diesel Engine Issues

I’m afraid my experience with Lombardini diesel engines hasn’t been brilliant! On my Carlton stump grinder, which was powered by the same Lombardini engine, the crankcase casting cracked. It was only a hairline crack but it was replaced under warranty as apparently, Lombardini had a batch of castings that were faulty.

I also owned a Lombardini diesel engine on a BCS rotavator, believe it or not, this engine was fine, however, the machine was stolen so I never found out if the engine was long-lasting or not or even trouble-free!

First Lombardini Engine

Anyway back to my present Predator 28 stump grinder, after just 30 hours the engine failed to start, apparently, this was due to the engine sucking in some soundproofing material that was on the flywheel cover. I did notice when the machine was delivered that this material was loose, however, I didn’t take much notice as I knew it had all been pre-checked.

When the engine was checked by the local Lombardini agent, they discovered that the machine had sucked in the soundproofing and the engine had overheated, this engine was replaced under warranty.

Second Lombardini Engine

My second Lombardini engine managed about 650 hours on the Predator 28 stump grinder, obviously, I checked the oil regularly and I suddenly noticed that the engine had used more oil than normal. In general, the engine burns very little oil, I probably add a small amount about every six weeks in normal conditions. The recommended time for changing the oil is 200 hours but I tried to change the oil at 100 hours as I feel it’s better to change the oil regularly rather than wear metal!

When my local Lombardini dealer stripped the engine down they discovered that dirt had entered into the engine, I don’t quite understand this as I’m always extremely careful with maintenance. The engine has a oil bowl filter which I am told is the best for dusty conditions. There’s also a clear Dyson type prefilter which removes most of the dirt and dust, which then goes through to the oil bowl and then through to a mesh filter and finally a spongelike filter before the air finally reaches the engine. I would expect with all these cleaning processes for the air to be clean.

I will clean the prefilter two or three times a day, depending on conditions and I will also change the oil in the oil bath filter halfway through the day if the conditions are poor.

However, despite this maintenance, I had to replace the engine at cost to myself! I see many tree surgeons who rarely clean their air filters out and yet they don’t seem to have had the problems that I have had!

Third Lombardini Engine 

After being unbelievable careful with this new Lombardini engine after just 160 hours the exact problem had started again. I checked the oil and on one particular occasion, I noticed that the engine had used more oil than it should have done! So now we are back to square one and another new engine is coming!

Fourth Lombardini Engine Coming

The engineers removed the air filter in front of me and to me, the air manifold looked clean, however, they did say that small amount of dirt had got through the filter and into the engine!

To me, the air filter is not doing the job if dirt is getting through. I have genuinely been cleaning the filter daily and more as I mentioned previously.

Just the other day I was speaking to a tree surgeon about the issue and he mentioned that he had a problem with his Timberwolf chipper in the morning. Apparently, it was blowing out black smoke and not revving properly. He checked the air filter and he said is absolutely blocked solid and once he cleaned the air filter the engine ran perfectly. I asked him how often he checked the air filter and he said he only checks it when there is a problem!

It really doesn’t make sense why these engines are wearing out so rapidly, especially as I am an owner-operator and take care to keep the engine clean.

What has been your experience with Lombardini engines on your Predator or any other stump grinder come to that?

Hydraulic Cooling Fan On Predator 28 Stump Grinder

The Predator radio remote stump grinders have an electric cooling fan to cool the hydraulics, this is due to the oil getting warmer with the radio remote stump grinders.

I am now on my fourth fan and so far this latest fan has lasted me several hours, fortunately, Predator has replaced these cooling fans free of charge. I believe that the issue with the fan is probably more due to the vibration of the diesel engine.

What’s your experience with the hydraulic cooling fan on your Predator?

The Fuel Pipe Burst

After about 40 hours of use the rubber fuel pipe burst, spraying diesel everywhere. I had to call the local engineers out to replace the rubber fuel pipe. On inspection of the old fuel pipe, it didn’t look like it was up to standard, thankfully the issue hasn’t happened anymore!

 

Hydraulic Oil Leaks

Ever since I have had my Predator there has been a hydraulic oil leak from the main hydraulic oil tank. I appreciate on top of the oil tank there is a breather and the system has to discharge a small amount of oil, however, this is more like a river of oil!

There have been attempts to fix this issue, but so far with no success! Obviously with oil leaking and then running onto the tracks can be an issue with people’s driveways, so there is a constant mopping process going on!

Have you had hydraulic oil leaks on your Predator?

Five Batteries In Three Years

It seems that my Predator 28 seems to get through a terrific amount of batteries!

The first battery went after about 60 hours, I called Predator to see if they could help, they talked me through a few checks over the phone which seem to point to the battery being the problem.

 

The RAC Came Out

it appeared that Predator were unable to come out to my breakdown, in fact, they have never been able to come out to a breakdown, so I decided to call the RAC!

The RAC came out and were slightly surprised that they were going to look at a stump grinder rather than a motor vehicle! However, the engineer was extremely helpful and carried out all the necessary tests that proved that the battery had failed. He was able to fit me and you battery but he did mention that it would not last due to the fact that the Predator battery is of a special specification for this machine due to the vibration. He was right, the battery lasted 48 hours!

I then purchased a third battery, I guess this lasted about a year before finally exploding on the golf course where I was working, this had to be seen to be believed!

I have never seen a battery explode before, however, after stopping the machine for about five minutes and turning the key to start the machine, aside literally blew out the battery! Thankfully this battery was replaced under warranty by Bosch.

The second Bosch battery stopped working for no apparent reason, so I’m now on the fifth battery that I had to pay for.

How has your battery been on your Predator?

Spool Valve Leak

I recently had to have the whole spool valve assembly resealed as it was leaking quite badly, it had been weeping for some time and then became considerably worse. Thankfully this issue is all fixed now.

Have you had any hydraulic leaks on your Predator stump grinder?

Charging Issues

I have also had several charging issues which is down to the Lombardini engine, I literally used to put the battery on charge permanently when I wasn’t using it rather than risking a breakdown. I had the engine checked several times and although it did have a replacement alternator or charging system replaced, it would definitely let me down if I didn’t charge the battery daily.

Radio Remote

 

I would definitely recommend paying the extra for the radio remote controls, it is so much easier and so much quicker to use than the manual machine.

As I mentioned earlier I have used the predator 38 stump grinder for approximately 100 hours and the radio remote has not failed me once.

Unfortunately, with my Predator 28 sometimes the radio remote can work faultlessly and although I don’t understand much about radio signals, I can appreciate that occasionally some interference is acceptable. However, sometimes my machine can cut out 40 times per day, once the radio remote cuts out the machine will stop, then you have to go through the starting procedure again.

I normally find that when the remote signal goes it will happen several times in a row and then just write itself on its own.

Due to the fact that the radio remote is losing its signal so often, I have overridden the sensor on the rear door. So that if I lose the signal the engine still keeps running, this saves a lot of messing around. This stops the engine shutting off at full revs, which I don’t like happening.

Once again, the predator 38 stump grinder didn’t fail me once with the radio remote!

How has your experience been with your Predator radio remote?

Vibration Issues

I believe that many of the issues that I have had to deal with unfortunately come from having a diesel engine which brings vibration issues. After using the Predator 38 petrol machine I can see that the vibration is considerably less than the diesel machine.

 

As you can see in the photograph some of the guards have suffered from metal fatigue. Once again I am sure this is from excessive vibration from the diesel engine.

 

Find More Stump Grinders Here

 

To Conclude

I feel that I have been quite unfortunate with my Predator 28 machine. It seems like I may have had a Friday afternoon machine. I also believe that the diesel engine has created a lot of vibration issues.

If I was purchasing now I would definitely go for the petrol machine as it has extra power, much less vibration. The diesel model and is much quieter which is actually really nice if you’re doing a days work!

As I mentioned earlier, the predator 38 radio remote petrol machine is a great all-round machine. Especially for getting into those narrow gateways that we so often come up against in the UK. If you are looking for a stump grinder the petrol model could be a good option for you. I will definitely be looking at one.

It would be great to hear about your experience with your Predator machine. Or come to that, any other make of stump grinder that you are using. Maybe you could write a review of the Predator 28 and 38 radio remote stump grinder?

Thank you for reading and please feel free to comment below.

Roy Bretton