Weekend of updates...well...almost

LowRider CNC Your Builds
1

Finally had a weekend with time to work on some upgrades for my LR4.

I was planning on on finally cleaning up the wiring and adding router control from my jackpot. Got pretty close on that one but I’ll come back to it.

I also planned on reprinting my core. I suspect that my current core (printed out of PLA) may have deformed over the summer in my garage here in extreme southwest AZ. I was still able to successfully cut foam on the machine in Sept but noticed the core was loose on the rails despite tightening up the adjuster screws. I had actually noticed quite a bit loose on the machine even earlier - but most of it was just screws I suspect I may never have gone back and fully tightened after initial assembly.

So I decided to bite the bullet and redo my core (and possibly a few other bits) in PET-CF. I ordered some Siraya PET-CF and it’s been sitting here for a few weeks as I worked up the nerve and prepped my machine. My old homemade 3d printer I had upgraded to an all metal hot end and done quite a bit of printing in various Nylons - but since getting my Prusa Mk3 (later upgraded with MMU2 and to a Mk3s. I had also bought a Nozzle X hardened nozzle when they first came out but the Prusa just worked so much better than my old printer I never bothered to install the Nozzle X as I never got around to any material that would justify it. But honestly after 8 years of use I was suspecting my nozzle was ready to be replaced anyway. So I dusted off the X and finally installed it this week.

Confirmed things were printing well with PLA still and then started prepping for trying the PET-CF. Did a PID calibration a 295 - but hit MAXTEMP. Tried again at 285 and it went well, so then did a thermal model calibration. Seemed alright…Tried printing a little test piece for my wife’s son’s RC car and twice in a row got about 6mm off the build plate and hit MAXTEMP printing at 295. Ok…too close to the MK3’s 300c max. Dialed back to 290 and tried again…success! Part looks great, even better than the one I did a week ago in PETG with my old nozzle.

So..bit the bullet and tried the core at 290. I’m running really slow at 0.20mm layers and a 0.4mm nozzle with max volumetric flow throttled to just 6mm3/s to make sure my hot end and 0.4mm nozzle can keep up. 42 hour print. Ugh…but I’ve got nothing better to do so let’s go for it - will be worth it if it works.

And it almost did.

image
image1621×912 191 KB

Except 30 minutes before it finished it hit MAXTEMP and shut down again :frowning:

Ugh. It’s just a few final outer layers on one side, and the print look gorgeous at first glance…I started thinking about maybe just trying it…but then I noticed 2 bigger issues.

First the other side has a BUNCH of zits…and they are SHARP. Could probably clean them off ok though…I assume they’re because I ran very little retraction as I was warned PET-CF doesn’t do well with retraction. Not the end of the world…The other problem though:

image
image1621×912 254 KB

Well, shoot. I had a layer shift right at the start of the print that I never noticed. My printer is in an enclosure with fairly poor light and I’ve got a bunch of boxes in front of it so I kind of have to lean over to even get to it right now. So even though I had checked on the print regularly I totally missed it :frowning:

And the part weights 527g so I almost certainly don’t have enough left on this 1kg spool to do another try.

I’ll probably print the tool mounts and maybe some braces the next few days to get a better feel for the PET-CF while I wait for a new spool to try again on the core. Just so frustrating to have a print go great for 41 hours then fail in the last 30 minutes.

The other upgrade is going better…but hasn’t made it to the machine yet.

I already shared some of this in @jeyeager’s amazing sandbox post. Short version to catch everyone up…I was playing around with claude and the Fusion MCP and ideas to clean up some of my wiring and let the jackpot control power to my router. You can see the renderings in the linked post…but the meanwell DIN rail power supply I had been waiting on finally arrived and I was able to start wiring things up:

image
image1621×912 478 KB

(That’s also a roll over WS2812B’s and a little WLED controller - claude helped me update @jeyeager’s usermod to the new format and build it against the latest WLED…I haven’t actually tested the usermod itself yet. Will share a PR with the changes if it does work when I finally get around to testing it.)

I also printed the case Claude designed and it fits…but had to hit three local stores to find the right length 4m screws to mount the DIN rail:

image
image672×1194 216 KB

It IS fully wired now and fits in the box. I just apparently forgot to take a photo…and haven’t double checked everything or tried putting power to it just yet. I’ll still have to mount it to the plate on my LR4 and make the final wiring harness between it and the Jackpot.

Oh well, at least the weather is finally getting nice enough I can spend time out in the garage without running the garage AC so hopefully progress will go better.

2

A PLA core deforming in a hot garage is a useful warning for anyone in a hot climate. What material are you reprinting it in? And did you notice the looseness come on gradually through the summer, or all at once?

3

Try bumping your temperature down to 287.

I printed all the parts from my Lowrider 4 out of Siraya PET-CF at 290F on my MK3S+.

My setup’s a little different because I’m using a 0.6mm diamondback. I only had a problem with one part at 290F, I think it was part of an end stop… I printed it twice and hit the max temperature at exactly the same spot both times. The third time I lowered the temperature to 288F and it worked fine.

4

Keep your pet-cf in a dryer, i printed 2 full lowriders with that brand at 280 degrees, perfectly with an adventurer 5m, (used the Qidi printer profile with the reduced temps)

5

Pet-cf is the go to for hot climates. That parts are not going to melt/deform

6

Thanks, and I see now jhitesma already mentioned PET-CF in the first post, my bad. Good to hear it holds up in the heat. Did you have to change anything else for it, like a hardened nozzle or drying it before every print?

7

Thanks for the feedback/suggestions guys. Honestly I’m not even sure my original PLA print did deform - but there’s plenty of reasons I suspect it did right now. One thing I can do with this print is compare it to the current one to look for any deformation.

I’ve had a diamondback on my amazon wishlist for a long time…don’t think I’d use a 0.6mm often enough to justify the cost but I may consider picking up another hardened nozzle in 0.6mm for the next attempt.

The first two test pieces both seemed to fail at the exact same spot with their MAXTEMP errors so when they went through ok I figured it was worth the try on the big print…just didn’t expect it to go 40+ hours then do it at the last minute :smiley:

Figure I’ll try reprinting some of the other parts in PET-CF since I’ve got almost half a roll to use so it will let me experiment with some temps and the only real downside is I’ll have more parts in PET-CF to upgrade with :wink:

Didn’t know it would even print at 280 - I thought 285 was the recommended minimum. if it can print acceptably at 280 then I don’t feel as nervous about going down to 285 to give myself a little more headroom on the overshoot.

One nice thing about living in the hot dry desert is I’ve never had much of an issue with hydroscopic filaments actually showing signs of absorbing moisture. Did have one roll of taulman nylon I had to put in a 5 gallon bucket with an incadescent bulb to keep it from stringing - but other than that our natural low humidity has let me not worry too much. This roll I plan to just use before I need to store it.

I am impressed by the PET-CF overall though. Love the look and finish it gave and it really does seem impressively stiff and strong. The little test pieces from my stepson’s RC part surprised me at how much effort they took to break. I was expecting them to be a bit more like PET-G and flex more than snap but eventually they did snap. Took a lot more force than I expected though.

8

Used an original FF 0.6 nozzle

9

Thanks! Did the stock nozzle hold up through two full LowRider sets of PET-CF, or did you notice any wear?

10

Ff 0.6 nozzles are supposed to be hardened, that said they didn’t like the change to print petg later. My guess is that less than 35 usd for a nozzle should not make a big impact in your budget