Air-struder installed, now I'm getting bulging.

[d1rron]

So a week or so ago I ordered a Fly-N-Strude. Then I realize that there is a printable model that does effectively the same thing (Air-struder). So I printed it out and installed it. Now I get bulging in some of the first layers (but after the actual first layer) and then it seems fine. I shortened the bowden tube a tiny bit so that it's just under 4" now. Perhaps I need to shorten it more? I'm not sure if much weight is being transferred to the effector. It seems like the bungees are doing most of the suspension. But yea, Idk. Any ideas?

Here's what's happening (Hatchbox PLA. 195°hotend, 65°bed):
http://i.imgur.com/FB0A9Np.jpg

http://i.imgur.com/eGeVr9c.jpg

And here are just some pictures of the Airstruder setup. Perhaps I need make some sort of adjustment?

http://i.imgur.com/7qyXJae.jpg

http://i.imgur.com/WZ8Ttjb.jpg

http://i.imgur.com/ZpE2jte.jpg

[ZakRabbit]

Did you re-calibrate your extruder? Re-calibrate "Z?" I can see where Z might be slightly lower with the added weight on the effector. I can also see where there might be less friction on the bowden tube causing slightly more extrusion as well.

[d1rron]

I did recalibrate. I even had to recalibrate horizontal radius which I thought was weird, but I was also running a little cooler since I was printing PLA instead of ABS. Anyway, it's calibrated as well as it was before as far as I can tell. I got my Fly-N-Strude kit today so maybe I'll try that in place of the Air-Struder, but there doesn't seem to really be much difference. :/ The weight seems to be distributed to the bungees, and not on the bowden tube. It sits at the same height without a bowden installed.

Not sure what else information would be helpful.

[ZakRabbit]

I did recalibrate. I even had to recalibrate horizontal radius which I thought was weird, but I was also running a little cooler since I was printing PLA instead of ABS. Anyway, it's calibrated as well as it was before as far as I can tell. I got my Fly-N-Strude kit today so maybe I'll try that in place of the Air-Struder, but there doesn't seem to really be much difference. :/ The weight seems to be distributed to the bungees, and not on the bowden tube. It sits at the same height without a bowden installed.

Not sure what else information would be helpful.

I'm just trying to think of the things that may have changed (bad habit, ex auto mechanic and specialized in diagnosis). So, the obvious is a physical Z height change from having the weight of the extruder and stepper now partially (possibly) transferred to the effector. The other possibility I see is the shorter bowden tube allowing a higher efficiency due to less friction which is actually causing an over extrusion situation. You do say that it's only on the first couple layers so it sounds like a physical Z.
You can try mhackney's trick of printing just a single layer then measuring it against what was programmed and adjusting Z height.

[ccavanaugh]

Some of the bulging shown is characteristic of too much heat on the bed with PLA. 50-55C is normally plenty for PLA. If needed, preheat and let it heat soak for a few minutes for better heat distribution or use a heat spreader.

[d1rron]

I've been printing PLA with a bed heat of 65-70 since I got the printer in February without a single issue. This problem didn't arise until I installed the air-struder. I have made sure that my wiring is separate for the end stops and near the controller I wrapped them in anti-static packaging to help isolate them. I'll probably remove that and wrap them in kapton tape when I have some time. I'm going to double check z height and bed level again here soon. I thought it odd that my horizontal radius needed ajustment after installing the air-struder so now that I've made sure all of the weight is off the effector (it hangs at the same height without the bowden tube installed) I'm going to check that stuff again.

[stonewater]

any news on your bulging parts? (man that came out soo wrong) anyway, I was thinking of getting an air struder or a fly n strude, but I was waiting for a resolution to your " problem"

Tom C

[d1rron]

I don't think the Air-struder is at fault.

I've attempted to print a bed level print and failed miserably. It seems that I have that issue where outside of the triangle between the towers, the nozzle lifts because it's only level inside the triangle. Before realizing that I was able to get my Z height dialed in a little better and a lot of my issue went away. I had intended to further calibrate, but I'm stuck at this triangle leveling issue. I read something a while ago about it, but can't find that page now. So I'm sort of at a loss. I might just set everything back to default and start calibrating from square one again.

Pretty lame, I'd really like to get back to printing again.

I'd say don't hesitate based on my experience. A lot of people seem to have had great success. I ordered a Fly-n-Strude, but I'm kind of using a hybrid between that and this: http://repables.com/r/531/" onclick="window.open(this.href);return false;

The thinner bungees that came with my Fly-N-Strude seemed to have helped a bit over the rather thick ones I was using, and I installed the little bungee stops for the trucks.

[Jimustanguitar]

Is there any slop in your arms and u-joints? Can you wiggle the effector when the motors are engaged? If there's any wiggle room, perhaps the bungees are lifting the head at certain points and you need to figure out how to remove that slop.

[d1rron]

Installed Tricklaser CF arms recently and it seemed to have really helped, but I also started over completely with bed leveling and tightened everything up to be sure nothing was loose. So far it's looking good. It's an ongoing process of trying to improve accuracy little by little, even if it's printing pretty accurately. I figure there's always room for improvement. Lol