What to buy, Bulldog xl or clone extruder?

Hi guys,

I am sick and tired of the plastic extruders, so i want to buy a direct drive, it has to be 3mm however.
I was thinking of the bulldog extruder, but it is way overpriced imo.
So i was thinking of a clone, but i see many advertised as 1.75 mm and others as 1.75 and 3mm but with the same pictures provided.
Is the only difference between the lite and the xl the geared motor??

i find that a clone + the geared motor i have to buy comes to about half the price of the original bulldog xl.

I was thinking of this one [www.ebay.com]

What do you guys think?

I'm looking at the same one, but as I posted in another thread, I might try smaller version like the Micron, but when faced with shelling out £200 you need to make sure there isn't another way...the one you listed plus an adapter means I could use nema11 with planetary gears, which would come to £65 ish for almost identical setup. but I'm waiting to try another low cost option which looks lighter, if it's not good enough i'll try some mods, but the principle on the expensive ones is pretty much the same as the value options.
Though as much as a good direct might be the more accurate way to go, I'm thinking of adding another rail above X with a carriage just for the feeder, so it can move in line with the hotend, keeping filament length static. It's easy to implement on my setup, and I have a spare 12mm rail that wasn't upto scratch for use anywhere else.

Hi,

I think the gap between the driving gear and the extruder's body is too large. There's a risk of jam, especialy with ABS or Flexible filaments.
Try to find an extruder that drive the flilament thight enclosed from start to end.

++JM

Have any of you considered a bondtech extruder? It's in the similar price range, but a bit of a different design. I would love to hear some opinions on one or the other, or even a direct comparison between the two... I am pretty sure I will need to upgrade to something better than a homemade cold end when I am done with my build (if that will be the limiting factor for print speed/quality), so I better start researching early...

I have a BullDog XL extruder. I purchased it after considerable experience with a terrible design (QUBD) and careful and critical review of the available options. Over the last year I have used it for ABS, PLA, and TPU filaments and it has been perfect. It has never chewed a divot into the filament and lost grip. It runs only slightly warm at 600 mA. I consider it a bargain at $150 because it works exactly as it should. I did not have to do anything extra- no mods, no tweaking- it worked perfectly from day one.

I don't have any political beliefs about clone vs original designs one way or the other, just observations. If someone is selling a part for a high price, someone else will come along and sell a copy for a lower price. That practice is as old as business. If they can match the quality of the original, buy the copy. The original designers who complain about cheap copies putting them out of business but took no steps to protect their design (via patents, etc.) deserve to have their lunch eaten by their low cost competitors. There is nothing new about this. There are a lot of people who don't understand the value of quality and will buy any piece of junk if the price is right. Quality suppliers being put out of business by low quality copies that don't work is also as old as business.

Before you buy a clone, see if there are any user reviews, and if there are, do the reviewers know what they are talking about? Ignore reviews of the original part (including mine, above)- those do not apply to the clone. If there are no user reviews of the clone you're looking at, don't buy it. Let someone else with more money and free time than you buy it and review it first. Be as critical of reviews as you are of the part's design. Look out for reviews on sites like Amazon.com that seem to all be written by the same reviewer and have unusual/questionable grammar. I've seen items with 10 reviews that all seem to be written by the same person/shill. Ignore reviews by people who just received the item last week. It takes time and use to know if the part is actually a good performer. Look for long-term, heavy-use reviews.

When you buy an unreviewed clone, you're gambling that the person/company who copied the original did so accurately. It seems that that is rarely the case as evidenced by the numerous problems reported here by people using clones of different hot-end designs. The real price of a clone isn't just the money you pay for it. The real price includes the time it's going to cost you to get it working and keep it working, and prints that will have to be redone. If you put zero value on your time, then take a chance and buy the clone, otherwise, buy the original, well reviewed part(s).

Edited 2 time(s). Last edit at 02/05/2016 01:02PM by the_digital_dentist.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I bought a Bulldog XL clone from Robotdigg a few months ago. I haven't used it yet, but their parts are usually pretty good quality.

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Thanks for the info guys, especially you The digital dentist.

Gmh39, that bulldog xl looks really interesting, to bad you haven't tested it yet. [www.robotdigg.com].
I really can't find a review of that extruder, just one buyer who rated it 5 stars on a retailer site.

Robotdigg does seem a popular manufacturer, i am doubting to buy one of those for 75 dollars, or an original one from a retailer for 133 dollar . It seems to be the best clone i have came across

Edited 2 time(s). Last edit at 02/05/2016 12:14PM by Govahnator.

Though the Bulldog has what looks like a square gearbox same size as other components, so all looks neat, I've not seen that as a separate item.

Thats true, the robotdigg extruder has it as well, i am not sure to buy the robotdigg xl or the original bulldog xl

Edited 1 time(s). Last edit at 02/05/2016 12:50PM by Govahnator.

Quote
Govahnator
Thats true, the robotdigg extruder has it as well, i am not sure to buy the robotdigg xl or the original bulldog xl

The robotdigg one is a round Gearbox on the motor and the square bit is in fact an adaptor piece. I bought 2 a few months back one for me and one for a machine I was building for someone else and that one does work quite well.

The only issue was the gap between the push fitting and the robbed gear. This is relatively easy to fix for 1.75 mm filament and prob not much of an issue with 3mm stuff. What I did was to get 2 spare push fitting for it used on as a guide and drilled a 4mm hole thru it and into the one at the opposite end then swapped that far one for a new one and did the same.

I then ended up with a 4mm path all the way thru the thing which meant I could push the PTFE bowden tube almost to the Hob hence reducing any chance of the thinner filament bunching up in the extruder body.

Hope this is a clear as mud but if you need any more info please ask oh and the thread size in the body is M6.

HTH

Doug ps they are about $78 or was when I got mine.

One major part missing from the Robotdigg clone is the foot that has the slot to mount the hot-end. You'll have to come up with your own way to do that or pay another $30 to get the foot from another site.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Quote
the_digital_dentist
One major part missing from the Robotdigg clone is the foot that has the slot to mount the hot-end. You'll have to come up with your own way to do that or pay another $30 to get the foot from another site.

Yes that is very true I fabricated a strap from 3mm thick Aluminium strip to clamp to one of the vertical (The Z tower to be exact) I forgot to mention that bit Sorry

Doug

Thanks for the reply's guys,

I have the feeling i need to buy the original one to be safe.

i found one ( it should be original but i dont see the bulldog logo on the extruder ) at a german retailer for 119 euro +10 euro mail. Wich is cheaper and faster then to buy direclty from rrd. [fabber-parts.de].

The robotdigg clone doesnt have the foot indeed, but i read that the foot wich comes with the original doesn't fit e3d v6's, so i have to print it anyway ( wich makes it less full metal grrr )

Edited 1 time(s). Last edit at 02/06/2016 09:02AM by Govahnator.

The foot that comes with the BullDog XL can be made to fit the E3D v6 very easily. There are three minor problems fitting the two together:

1) the slot in the foot is just a little narrow for the E3D v6, corrected with a small, flat file in about 1 minute. I filed the hot-end.
2) the heatsink fins partially restrict access to the screws that hold the foot on the BullDog. I don't know if that's E3D's fault or the BullDog's fault but it is very easily fixed with a round file or Dremel tool in about 1 minute.
3) there is excess space between the top of the E3Dv6 and the bottom of the BullDog XL. That is easily fixed by adding a washer between them.

I have used the combination for over a year and it has been absolutely reliable, and well worth the minor inconvenience of making these extremely minor modifications to marry them.
As you can see in the picture, I tapped the holes in the foot so the whole assembly is held onto the extruder carriage with just two screws.



Edited 2 time(s). Last edit at 02/06/2016 09:38AM by the_digital_dentist.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I've left the extruder as one of the last parts to integrate into the design,
when maybe it should have been one of the first, with everything else designed around it.

The good thing about the bulldog is you can use it as a bowden(but so can some of the cheaper solutions), because I'm not sure how I would mount it direct, the feet on the bottom probably would not fit my setup, its a lot to shell out if it doesnt fit, and if you have to then start making custom parts to hold it, you might as well got the extra mile and make a custom extruder. The Micron has more chance of working with my setup, and I found the extruder on it's own under ebay listing as makergear, but just to be sure I modeled the Extruder & Motor & my carriage, just to see how things would look, but it convinces me I would want it off the axis. I had been using the standard hotend plate, but my hotend wasnt secure enough without a bit of wire, as the plate had a little 1mm extra groove, so I ordered one of the horseshoe type ones(smaller) without extra groove, but no sooner than I ordered I found a much better way of securing my hotend...a 16mm rail support also smaller than the plate....Now it's Tight, but obviously now non standard fitting, if I wanted a direct, but then are any of these extruders really following a standard(hole spacings), and if so are they all making same mistake, perhaps a new modular standard is needed.

Digital Dentist, would the setup be better straddling the X rail, set back an inch or 2, with L bracket rather than square?

The extruder/hot-end will not clear the X axis belt to contact the bed plate if the whole thing isn't shifted downward a bit. But shifting it downward for clearance means that the shelf can't engage both screws in the bearing block. So the rectangular aluminum standoff engages both screws in the bearing block and allows the extruder shelf to shift downward the required amount. It would have been more compact to eliminate the rectangular standoff, but it just would not have worked with the rest of the mechanical configuration.

I tried to design my printer around the parts I was using/intending to use, including planning for electronics and cabling, which are afterthoughts in most designs (as they were in my first generation printer, MegaMax). As I acquired new parts to use I made CAD models so I could model the whole machine and check fit and clearances before building. Of course, there were some changes along the way, but it's a lot easier to make changes in CAD than to modify hardware. The results completely justified the effort.

Edited 2 time(s). Last edit at 02/06/2016 12:00PM by the_digital_dentist.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Does the belt have to be underneath, from what I can tell in that pic it could be ontop?
even the rail I might have tried it rotated 90 degrees so it was like a monorail,

then you could straddle both sides, but I dont know the limits of the Rail.
It is what it is, and works well for you, I'm sure there's a good reason to settle on what you did.

As I've discovered there's always more than one way of doing things,
I've had the belt all sorts of ways, top, middle, side,
though the current side would be top if I had the rails above each other
trouble is I dont have enough parts to explore all designs at once
and its a shame to break things up if they are working.
before I started to build I modeled everything too, tried multiple configs,
but only when building did a few more present themselves,
and even more configs when I can print parts when ever I want.

Edited 1 time(s). Last edit at 02/08/2016 08:01PM by MechaBits.

If the belt were on top, the extruder would would be placed higher so the body of the extruder would clear it, unless I turned it around so the back of the extruder faced forward, but then I can't see the gear turning, etc., which is less than ideal.

I settled on this configuration only after carefully scrutinizing about 10 different configurations. Among the selection criteria were ease of assembly/disassembly, minimization of printed parts, moving mass and weight distribution, fit within the printer's frame, etc.

I think in an ideal printer design, you start with the extruder/hot-end, design the mechanism to move it, then all the other mechanisms around it, then finally the frame to hold it all together. I didn't do it quite that way, but close. There were a lot of tweaks and changes and trade-offs going on all the time, because I used a lot of scrap parts that weren't always ideal and had be be designed around. Buying more ideal parts would have been nice, but pretty expensive, since most would have had to have been new.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I have decided to go for the orginal bulldog xl extruder guys, i found it for 120 euro's = 132 usd.
Seems like a good price.

Thank you all for the advice