Mhackney's Rostock Max

[mhackney]

Ok, I have been able to slice and print a simple calibration cube with the new Photoshop 3D Printing support. It is VERY primitive and buggy. I don't recommend anyone actually trying it until things stabilize! It is very painful to create a profile and since everything is encapsulated in the profile, making changes is very difficult, not nearly as easy as it is in existing slicers. The USB communication is particularly difficult and there is virtually no feedback or control once connected. But, for those of you with high intestinal fortitude, here is the Rostock Max profile and installer. Simply unzip and read the readme.txt file.

SeeMeCNC Rostock Max Profile.zip

(8.6 KiB) Downloaded 230 times

Cheers,
Michael

[mhackney]

My E3D hot end came in today.

[img]http://mhackney.zenfolio.com/img/s5/v12 ... 7821-4.jpg[/img]

Time to do a little wiring and hook it up. I'm looking forward to it based on all the great things I've heard and seen.

cheers,
Michael

[Eaglezsoar]

My E3D hot end came in today.

Time to do a little wiring and hook it up. I'm looking forward to it based on all the great things I've heard and seen.

cheers,
Michael

Did you get the thread in thermistors also? They work really well.

[mhackney]

Not yet, they did not offer those when I bought this one. I will probably order a few from ebay. With a cartridge heater and a threaded thermister, set up is painless!

Where do you get yours?

cheers,
Michael

[dpmacri]

I got mine here: http://m.ebay.com/itm?itemId=221312429218 which I think is the standard place to get them.

[mhackney]

Yeah, I think its the ONLY place to get them! I just finished ordering a few.

thanks!
Michael

[mhackney]

Viki arrived:

[img]http://mhackney.zenfolio.com/img/s5/v13 ... 8019-3.jpg[/img]

That was quick. Nice little unit. Looking forward to hooking this all up.

[bubbasnow]

I got mine here: http://m.ebay.com/itm?itemId=221312429218 which I think is the standard place to get them.

is that link broken or sold out?

[mhackney]

Must be an old link he posted, here is the current link.

[dpmacri]

Weird -- the link works from my phone (which is what I was on when I posted it), but not from a computer .

[dbarrans]

Michael, how did you avoid breaking your tap? I broke my #25 carbide bit on Wednesday, most likely because the drill chuck on the turret wasn't quite lined up with the collet chuck on the headstock. Before the bit broke, it drilled a hole too large for an 8-32 tap.

I got another carbide bit, this time a #29. I got everything lined up this time and avoided breaking the new bit after a failed attempt with a cobalt bit which only dulled the bit without drilling anything. Then I put a homemade tap guide (no spring) in the turret chuck and immediately broke my 8-32 tap. I did use Tap Magic, but still broke it. Darn.

I've got $40 in broken carbide and I'm not really any closer to getting a ball mounting figured out. I think I may try to cobble together a sphere-making attachment for the lathe next, unless someone can suggest a source for some softer 1/2" steel balls.

- dan

[mhackney]

Dan, it sounds like you did everything correctly. I use tap magic too. I suspect your technique. On hard materials you might only be able to tun the tap wrench 1/4 turn and then back out, then repeat 1/8-1/4 turn at a time. You can feel how much force you are putting in and should not allow it to get too high before backing off to clear chips, etc. An 8-32 tap is not that fragile so you must be applying a lot of torque. Does this make sense, do you think you were not backing off frequently enough?

cheers,
Michael

[dbarrans]

I barely had it start to bite for cutting threads. I'm certain it was my technique, but I don't really know what I could have done differently. It wasn't cutting at all, so I put a bit more pressure towards the hole. Then it started cutting and caught and released a few times, then it broke. Before it broke, I did back off a half turn or so several times, each time it started cutting. I only got a couple turns in before it broke. It was a bottoming tap, so I didn't expect it would be easy to get started.

The tap is http://www.mcmaster.com/#catalog/120/2541/=qbs9jy" onclick="window.open(this.href);return false;, can't break too many before this project gets real expensive.

- dan

[dbarrans]

The balls are C60. The tap is for C30-C40. I'm pretty sure that's my problem.

- dan

[mhackney]

That's your problem - a bottoming tap. You need to start threading with a taper tap - you could use a plug tap too but taper is much better. The taper tap starts to cut the threads more gradually. The threads on a bottoming tap are full size and immediately start cutting full depth and requires a significant amount of force along with alignment difficulties. This is fine when you have 5+ threads already cut to support and align the tap but not to start threading. I use TiCN coated high speed steel taps like these to cut threads in the C60 bearings. Remember, the tap hole is bored over size so a lot less force is required to cut, which allows you to use HSS taps like these. You don't need a C40 tap if you are cutting into an oversize hole as I described.

regards,
Michael

[dbarrans]

I tried a #25 drill bit, but that made a hole too big. The #29 is the recommended size for 8-32 threads, and I calculated the #25 was to the #29 as your oversize #31 was to a #36 for 6-32 threads. Either I got that wromg. or maybe I had the #25 slightly off center, making a larger hole than it would have otherwise.

- dan

[dbarrans]

Interesting. I just got around to measuring, and it seems my #25 bit is .149" in diameter, but I drilled a hole .167" in diameter with it, which is larger than the 8-32 studs I have, which are .158".

I guess the only thing left is to order another tap set and another #25 carbide bit. AND be sure to line it up with the center of the ball this time.

- dan

[mhackney]

Dan, a #29 is recommend for 75% thread engagement for 8-32. For hard materials (like these C60 bearings) a 50% thread engagement is quite acceptable and MUCH easier to tap. That is a #27 drill for 8-32. I like this tap chart because it has all of this information on it (and it's free!). There is a standard drill chart at the bottom too.

You want to order a #27 drill and an 8-32 taper tap - that's all you need. You don't need to bottom tap these holes. A few threads to hold the stud are all that's needed. A drop of blue Loctite and you are good to go.

[geneb]

Can you post that chart some place for download? I'm not joining yet another site just to download or print a stupid chart.

g.

[mhackney]

Here it is, but I did not have to join any sites to download it. Perhaps I got the original from a different source, not sure now.

Tap Drill Chart.pdf

(196.17 KiB) Downloaded 175 times

[geneb]

Thanks!

g.

[mhackney]

No problemo.

Gene, every time I see that orange Max in your avatar I get jealous! That is a thing of beauty!

cheers,
Michael

[mhackney]

A lot of folks here would die to have this problem - my PLA is sticking TOO well to blue 3M painter's tape! I don't know what's up. I did just get a new roll of tape and it is identical to my last roll. But, for some reason, the PLA almost bonds to it. I can't remove the part without destroying the tape and then I have to spend a lot of time pealing the tape off the part. No fun. Has anyone run into this?

Cheers,
Michael

[bubbasnow]

A lot of folks here would die to have this problem - my PLA is sticking TOO well to blue 3M painter's tape! I don't know what's up. I did just get a new roll of tape and it is identical to my last roll. But, for some reason, the PLA almost bonds to it. I can't remove the part without destroying the tape and then I have to spend a lot of time pealing the tape off the part. No fun. Has anyone run into this?

Cheers,
Michael

has your nozzle clearance changed to make first layer smash into the tape???

[mhackney]

No, I should have mentioned that I've checked everything multiple times and attempted many prints. I use a SS feeler gauge to set my nozzle so I am confident it is dead on. Unfortunately I don't have any of the other roll of tape.