My extruder mount is rocking!

And not in a good way. It has a fair amount of play between the bearings and the x axis rods. Is this normal?

When I hold the extruder in my hand when facing the front of the printer I can rotate the extruder assembly right and left maybe 1 or 2 degrees. The play is coming from the bearings whose ID is larger than the x axis rods diameter. I realize there needs to be a slight difference, but I think it is too large.

Is this “normal” for the Taz 5?

I have the same thing on my Taz 5. I also get some movement of the extruder from flex in the printed toolhead mount.

Did they source the wrong size x-axis rods? I think this is something that needs to be fixed. It could be a small part of why my prints, while very good, are not perfect. I think removing play in the print head can only help in any case.

No, everything is 10mm. The IGUS bearings they chose though are meant for a compression fit sleeve. The printed bearing holders on the TAZ just can’t put the proper compression on them so they are oversized. In some cases this can be improved by putting a slight twist on the Y-axis bearings, and squeezing the top and bottom bearings on the x-axis closer together.

A few of us have given up on the IGUS bearings and upgraded to hardened linear rods with linear ball bearings and are very happy with the results. There are a few posts on it in the forums, has some misumi part #s in it.


So this is a known issue. Ok thanks. Irritating.

I am not sure if it would be classified as an issue. More as a design decision to keep costs in line with their target, lower maintenance (IGUS is self lubricating), sound level (bearings can be louder), etc. Good hardened linear rods for X & Y plus bearings can run $125. I believe all versions of the TAZ have been built using these IGUS bushings.

The nice part is the rest of the machine is so well engineered that it only takes an hour or two to swap it all out for those of us that want perfection in our prints.


Sorry to disagree but this is why the Taz can’t print well at high speeds. My R2 can print twice as fast and get better quality than the Taz. Part of it is the smaller build volume which allows for lighter and more rigid moving parts. But a big part is the play in the Taz system. They need to bump the price up and get rid of the slop. There are things you skimp on, and this is not one of them.

If I remember correctly the R2 uses bronze bushings that need to be lubricated over time and add mass to the toolhead. The R2 is a bowden setup so it can tolerate the extra mass. The TAZ being a direct drive needs to keep the mass as low as possible.

I agree that there is too much slop in the stock TAZ, but it seems like most people are able to tune that slop out. I was not able to, hence the upgrade to bearings. Saying that, my prints looked ok at 100mm/sec stock, but I wanted higher accelerations for sharper ABS corners. After the upgrade I can run 100mm/sec, 1700 mm/sec/sec acceleration at 0.14mm layer heights and get stellar prints.

I find each printer in this price range has its pros and cons. You have to choose the one that best fits your requirements and make it work for you.

So far I am impressed with the quality of the TAZ and how easy it has been to tighten it up in the few places it was not perfect for my needs. There are faster, more accurate, more turn key printers out there, but none of them have the open source hardware approach, build volume, ease of modifications, toolhead options, active community, and support team that backs up the TAZ.

All this is my opinion which is worth what you paid for it. :slight_smile:

Take care,

Sorry I didn’t mean to give the impression that I didn’t like the Taz. I do very much. Like the old phrase, if I didn’t care I wouldn’t say anything.

I did get some help from the help desk and I spread and tightened the bearing holders, that removed a lot of the slop, but there’s still about 1mm movement at the nozzle due to slop in the bearings. IMO you don’t want any. As in zero.

Anyway I am a perfectionist in some respects, and I can’t stand a mechanism that isn’t functioning the way it should. If we remove all the slop (or as much as possible) we should be able to approach the accelerations of the R2, and maintain quality. The only thing I don’t like about the Taz is the stock accelerations are slug-like, so for small details and models it is excruciating to watch.

I will be upgrading my printer with better bearings (tighter tolerance) and harder x axis shafts. But I wanted to bug Lulzbot techs about this because they SHOULD be doing this already. I spend over 2g’s for this printer. I expect good quality and speed. Not one or the other. Especially since it is clearly attainable with the design. Heck the frame is a brick S house. So we are 90% of the way there already. Spend another $200 and make this thing properly stock.

ps The r2’s extruder is very similar to the Taz. The only difference is the stepper is directly connected to the hob but in both cases the stepper is mounted on the moving mass. I’ve never lubricate the bushings on the R2. But the Taz’s print head weighs a ton, making it even more imperative to remove all slop. I will admit I have added a lot of upgrades to the R2 to get it where it is, so perhaps it is not a super fair comparison. But even the stock R2 has no issues with play at the nozzle.

Video I just shot of my 2 week old Taz 5

Gotcha, makes total sense. Thanks for the clarification on the R2’s extruder, thats a damn small direct drive!

Your video looks just like my TAZ did. Throw some better bearings on there and never look back! There is still some play in the tool head from the way the swappable head mounts, but that can be tightened up with 2 extra screws in the top corners.


Steven, I’ve read the other thread and I’m still not super sure about what to order. Could you list the specifics, such as the exact part number of the bearings. The link to McMaster Carr just takes you to the site. Also on the rod, not sure how long to order (I’m not in front of my printer right now, but would love to get everything on order).

Sure, I ordered everything from Misumi, they are the supply house that Lulzbot uses as well. I have included the Misumi part #, qty, etc below. This is the part list to replace X & Y. I left my Z alone as it was tight.

Linear rods are all 500mm long, 10mm in diameter.

These part #s are exact part numbers and define all the params of the parts like length, hardening, etc.

Part #, Description, Qty, Unit Price, Amount
PSFU10-500, Hardened LINEAR SHAFT - 500mm, 4, $18.69, $74.76
LMU10, Linear Bushings, 7, $5.99, $41.93

Misumi Links:
Linear Rods -[20-800%2F1]&PNSearch=PSFU10-500&CategorySpec=00000028943%3A%3A500

Bearings -

Outstanding, much appreciated. I went ahead and ordered the Y’s too, but right now they are rock solid.

Having read about sag due to the heavy heads, why not go to, say, 12mm dia. rods and bearings if going to the trouble and cost to change?

The 10mm bearings have the exact same dimensions as the stock IGUS bearings. That means it’s a simple part swap. If you went to 12mm you would need to redesign new bearing holders for X and Y carriage, print new Z guides, print new Y end brackets, and drill out all the aluminum plates. Lots more work, much greater chance of messing the machine up.


All that for 12mm…a lot. Thanks for answering.
Ordering a Taz 5 for early April delivery. This forum is a major selling point.

Thanks! Ordered the parts for x & Y axis’s.

Edit: Never mind! It’s so easy!

I got the parts today. Before I start disassembly, do I need any special printed parts for the install, or do I use all the stock Taz 5 parts? (Just remove the existing rods and bushings and replace them?)

Thanks again!

OK did the X-Axis install just now. Literally takes 5 or 10 minutes. There’s very little to do. Loosen the grub screws on the top x-axis rod and slide it out. Remove the two plastic bearings. The left one (when facing the back) comes right out. The right hand one you have to lift away from the printed holder and then slide it out. I use one of the old 10mm rods to pry it up while pushing it out to the right. Then you slide in the new bearings and slide the new rod through, and tighten the grub screws at each end. Next loosen the two grub screws for the bottom rod and slide it out. You’ll have to remove the bottom printed bearing holder. Remove it’s four screws. Then use an old 10mm rod and pry the plastic bearing out of that holder. Then press in the new bearing, and screw the holder back on lightly. Then slide the new x axis rod in for the bottom and tighten the grub screws. Finally tighten the holder while applying pressure skyward.


What a HUGE improvement. Zero slop in the X axis. Amazing difference. Lulzbot has to start providing this new hardware with their printers.