Author Topic: 3d printer - Leapfrog creatr conversion  (Read 5180 times)

Online BillTodd

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3d printer - Leapfrog creatr conversion
« on: October 25, 2021, 11:19:55 AM »
Finally remembered to take some pictures ...

I'm converting an old Leapfrog Creatr 3d printer to a Core XY design (core xy  is an arrangement of belts that allow the motors to be mounted on the frame)

The creatr is a stout design from a few years ago. The rod linear rails used are unfortunately rather wobbly and the leapfrog dual extruders are rather crude so replacing them with cheap hywin clones seemed the best option . 

I'm using a Bigtreetech Octopus board , with tmc2209 drivers, and their 3.5 inch touch screen.

The Saturn resin printer has found a good use printing various part. 

It's still a work in progress , and I have still to decide exactly what to do with the hot-end/extruder , other than I want it to be easily removable and swapable with other work heads (hence what you see in the pictures are just place holders for the yet-to-be-designed parts).
« Last Edit: August 08, 2022, 03:38:16 PM by BillTodd »
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Offline Brass_Machine

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Re: 3d printer - Leapfrog creatr conversion
« Reply #1 on: October 26, 2021, 11:00:13 AM »
Hey Bill

That's cool! I did not know Leapfrog even made a 3D printer. I like the core XY design... I hopefully I will be on my way to building one soon as well.

Eric
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Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #2 on: October 28, 2021, 04:13:48 PM »
Having fun with some extreme belt resonance ATM.

Not sure if I should add tension or let it off   - seems OK at slow speeds but much above G0 F15000 starts it honking like a mule  and then it quietens down at 20000 again (both way too fast to print but rapid moves are at this speed)

More tuning required
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #3 on: October 30, 2021, 02:16:02 PM »
I really did not think this would work as an MLSA part, so just  printed the one half of the aluminium parts as is.

So what we have here, is a geared extruder  (5:1) using a tiny 35mm stepper from a 8" disk-drive . I have replace one end cap with a 3d printed part (with the intension of replacing both end caps). It'll have a couple of bond-tech type grippers and a sprung lever to pinch the filament

The large gear (80T) is printed while the small gear , 16T, is a nylon(?) part from some random printer scrap . I have a 3d printed 16T gear with works but is a tight fit .

It required a little hand finishing to fit the stator exactly centred (the print was a little tight) and the bearing fits always require a slight clean-up.




Bill

Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #4 on: November 01, 2021, 11:18:08 AM »
Tadpole 2

Aligning two plastic stepper motor halves is somewhat more challenging , but with a little kinetic adjustment , it does work.

Now I have to finish the rest of the printer to try it out
Bill

Offline PekkaNF

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Re: 3d printer - Leapfrog creatr conversion
« Reply #5 on: November 02, 2021, 01:19:22 AM »

...but with a little kinetic adjustment , it does work.

Care to explain? Something like percussive maintenance comes into my mind, but probably not....

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Re: 3d printer - Leapfrog creatr conversion
« Reply #6 on: November 02, 2021, 07:26:13 AM »
Similar process , one fixes something that once worked but now doesn't  the other get something to work that never did.

tap, tap twist ... tap tap  twist , HAMMER HAMMER oops  that sort of things :-)
Bill

Offline PekkaNF

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Re: 3d printer - Leapfrog creatr conversion
« Reply #7 on: November 03, 2021, 06:28:19 AM »
Thank you. All clear now. I have done my share of tap-tap-tapiti-tap and tweak-tweak-blimey adjustments myself....sometimes even in system that mechanical stickiness, analog measurement (and sometimes even control loop) and digital/SW controls....sometimes it is hard to know even where to start.

Hope this gets sorted with relative ease.

Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #8 on: November 05, 2021, 12:10:38 PM »
Finally got around to wiring and  the extruder mount.

The connector is a 41612/3 but I didn't have one in stock (and Farnell wanted £18 quid for one or £250 for a 100) so had to make one from two bits of a full size 96way one .

There's wiring for dual extruders, 3 fans and a few spares for whatever comes up

Bill

Offline awemawson

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Re: 3d printer - Leapfrog creatr conversion
« Reply #9 on: November 05, 2021, 12:41:55 PM »
Neat  :thumbup:
Andrew Mawson
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Offline WeldingRod

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Re: 3d printer - Leapfrog creatr conversion
« Reply #10 on: November 06, 2021, 11:42:28 AM »
That is some proper ship-shape wire tendering!  It's going to pay off in reliability!

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Re: 3d printer - Leapfrog creatr conversion
« Reply #11 on: November 06, 2021, 04:44:33 PM »
Thanks :-)

I'm interested in how the resin printed parts will hold up over time.  It is surprising how the material changes : It comes out of the vat quite soft and sticky. After a half-hour or so exposed to a few watts of violet/blue light (405nm not really Ultraviolet) it hardens and dries. It can be filed , sanded, drilled, tapped easily.

After a few days , in normal light , it is noticeably harder and , in the case of white resin, changes colour from a ivory to a brilliant white (the hard resin is very fluorescent so I suspect the colour is the result of the final stages of polymerisation ). It also becomes noticeably more brittle, less flexible.



Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #12 on: November 06, 2021, 04:55:08 PM »
I've got the extruder mounted and wired. Heater block and fan are working , but the motor is not being driven (it's wired ok so must be a config issue).

I managed to squirt some filament by hand 

My Z axis home switch mount and cam prints failed  ( almost certainly) because of the low temperature as the resin gets very viscous below about 20'C. I'll have to revisit my cupboard heater tomorrow to get them printed.

 
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Re: 3d printer - Leapfrog creatr conversion
« Reply #13 on: November 07, 2021, 11:17:37 AM »
Fixed the extruder motor problem : it seems that by default the forth motor is used as a second Z axis , so a simple matter of shifting the driver and plugs along to the next slot .

The Tadpole extruder seems to work well  motor runs cool at 300mA .

Just got to sort the Z axis home switch
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #14 on: November 08, 2021, 05:08:39 PM »
well, we have a print ... of sorts

I'm beginning to think the Tadpole may have been an extruder too far...

It seems to work fine then randomly miss steps as if something was jamming inside.  I kept upping the motor current to compensate until it overheated and seized (plastic warping in the heat)

Print quality is OK though (without cooling fan ATM)

Not sure what to do now: make the tadpole out of aluminium as unoriginally intended or try to find the source of the random jams.
Bill

Offline MetalMagus

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Re: 3d printer - Leapfrog creatr conversion
« Reply #15 on: November 11, 2021, 07:08:39 AM »
Noticed you said you had used resin parts. On the Voron printer forum they advise against resin parts, especially if the print chamber is going to be heated. The reason given was that the resin parts are prone to "creep" over time so you begin to see fit and tolerance issues.

Just something to bear in mind if you start having any issues that are not easily identified.

Sean

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Re: 3d printer - Leapfrog creatr conversion
« Reply #16 on: November 11, 2021, 10:42:10 AM »
Yes thanks Sean,

The extruder is very much an experiment, it was intended to be made in aluminium.

I've had experience with resin parts and heat , they do odd things  like cracking apart at modest temperatures , while at the same time being almost immune to the soldering iron!

I might investigate some higher temperature resins.

In the meantime, I have rebuilt the extruder with a number of fixes which should hopefully  stop it jamming .

« Last Edit: November 11, 2021, 11:20:55 AM by BillTodd »
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Re: 3d printer - Leapfrog creatr conversion
« Reply #17 on: November 12, 2021, 05:29:36 PM »
Well I finally have a finish print

Lots of modifications to the tadpole prototype : Better spacing for the gears (it was a little too tight) ,Captive nut instead of threading into the plastic  and machining the bearing and stator fit to reduce the amount of 'fitting' required  etc. etc.

While I was at it I increased the side of the extruder gear bearing so I can get it out without disassembling the motor .

Still no part cooling.

Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #18 on: November 13, 2021, 03:33:18 PM »
This is what I like about resin printing...

This fan duct would be nearly impossible to make in one piece with any other method.

 
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #19 on: November 19, 2021, 04:43:43 PM »
Quick update.

Printer is working. This is its forth print in progress.

The extruder is working well when it works but is still being unreliable at times.


The resonance is fixed (for now) by switching off the tmc stelthchop mode, which is a pity because it's not as quiet now. I've tried to get Marlin's hybrid mode to work but it doesn't seem to want to disable stelthchop ever ???? (Expert advice welcome)

Speed is still being limited by acceleration, again marlin advice welcome!



Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #20 on: January 23, 2022, 07:50:08 AM »
I was not happy with the glass bed , I could not get things to stick to it and it took an age to heat to even 50'C, its 240w heat way too small for such a large piece of glass.

While watching the Prusa XL launch , I was taken by the idea of a segmented bed , so decided to build one for the FrogSpawn. While sourcing a suitable piece of cast tooling plate from the 'works' my friend overheard what I wanted it for and promptly donated ten 120x100 heater pads  - :-) perfect.

The mod involves bending the front of the existing Z plate , to remove a nice little 'finger-shear'  between the plate and the front of the frame. and mounting it below the ball-screw nuts to increase Z range. Four rectangular bars fixed to the underside of the Z-plate and a rear support , stiffen the Z-plate and provide mounting points for the Kastal 300 bed-plates

The heated bed-plates will mount on springs at each corner , with screws for adjustment.  Once properly adjusted the bed should stay trammed and level.

The nine 240vac 120w heaters will be controlled from a RaspberryPi Pico with a 9 way PID written in microPython  . 

The problem I have yet to solve is how to control the bed temperature from Marlin or, via g-code, from the BTT display controller.

Ideally, Marlin would be able to talk to the Pico via a spare serial port and report temperatures back to the display. However, I found no way to do this in Marlin :-(

My work around plan , is to intercept or monitor the serial data between the BTT LCD and the BTT Octopus board and intercept the appropriate M-codes .

Interception , means breaking the like between the two boards and inserting the Pico , but now the Pico would have to handle all the traffic and could be a potential bottleneck. 

Monitoring means just sniffing the data going to the Octopus board and picking up the bed control M-codes as they pass by. In order to let Marlin know the bed temperature , the centre plate's thermistor would have to be paralleled with both the Pico and the Octopus  . Any thoughts?
Bill

Offline WeldingRod

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Re: 3d printer - Leapfrog creatr conversion
« Reply #21 on: January 23, 2022, 08:49:45 PM »
3 point mounts are your friend on this stuff...  much easier to adjust.

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Re: 3d printer - Leapfrog creatr conversion
« Reply #22 on: January 24, 2022, 06:28:47 AM »
Yes, I did look at 3point mounts, but decided that corner mounts were simpler to implement . Hopefully, itll be just the one PITA adjustment session.
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #23 on: March 01, 2022, 08:42:57 AM »
Progress is slow here ATM  -I'm  lacking motivation and easily distracted

Such as converting a microwave oven to a UV curing device for the resin printer.

And now, the oven's transformer is pulling me towards making a small spot-welder .

And Stefan Gotteswinter's new grinder has me thinking about a surface grinder project

 :proj:
Anyway back to the segmented bed  - which I'm calling the Lillipad ( just to maintain the aquatic theme :-))

I've got the bed plates mounted and, as predicted above, levelling is a PITA but do-able.

I've bonded the nine heater pads to the plates and (since the photo) connected earth leads an thermistors to each.

All I have to do is complete the software to control it  - ( zero motivation )

Wire it  - (majorly conflicted as to where to put the controller   -i.e. put the SSRs on the Z plate to  reduce the number of wires  or drop a multicore cable down to a nice, and easily constructed, box on the base plate ?  - I'm almost certainly over thinking it.




Bill

Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #24 on: March 01, 2022, 08:56:17 AM »
Microwave oven curing station:

The cube in the centre is the yellow  PLA one printed above  - it fluoresces intensely in the 405nm blue light   
Bill

Offline Btje

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Re: 3d printer - Leapfrog creatr conversion
« Reply #25 on: May 02, 2022, 03:31:14 PM »
I have the creatr HS and am thinking of modding it to to have an improved printer of my CR10. I saw you post. Nice work. I have a question, why didn't you put the rails upside down?

Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #26 on: May 03, 2022, 05:35:03 PM »
 Hi Btje, welcome to the forum  :mmr:

Good question :-)

My immediate response is that the motors would then be poking up above the rail extrusions, if mounted on the rail itself (IYSWIM) . But really it was  just how it looked best to me in the cad model.  :D

It might have been a bit more difficult to mount the motors if the Y axis extrusion had been flush with the top . I don't think it would have caused any other difficulties.

If you do start a conversion , I'd love to see it, so do post a blog somewhere  :proj:





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Re: 3d printer - Leapfrog creatr conversion
« Reply #27 on: May 04, 2022, 07:58:00 AM »
Distraction 2:

microwave oven transformer based spot welder  -
works better than expected :-)   - happily welds 2x 2mm dexion angles, 15mm ball to steel and , most surprisingly , a steel ball to an aluminium plate
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #28 on: October 15, 2022, 03:54:43 PM »
Distraction 3:

One day I will get back to this project.....

Unknown 164  http://www.lathes.co.uk/unknown164/  a rusty shop made lathe with a intriguing vice , acquired and cleaned.
« Last Edit: October 16, 2022, 05:28:25 AM by BillTodd »
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Offline awemawson

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Re: 3d printer - Leapfrog creatr conversion
« Reply #29 on: October 15, 2022, 04:47:09 PM »
Thatís looking a whole lot more wholesome Bill  :thumbup:
Andrew Mawson
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Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #30 on: October 15, 2022, 05:47:21 PM »
Thanks.

It's a real enigma, it is well made but not well finished. Everything that needs to be good is good, but it's like they didn't have the time to add the finishing touches.

The tail stock lock clamp for instance: it is a neat design clamping rather than squeezing a casting, but i had the draw file and polish it to make it look nice.

The little vice's anvil is beautifully carved from the main body,  But they didn't remove the shaper marks before hardening.

If it weren't for the allen screws I would think this is 'war finish '  - the cross slide appears to be a hardinge cataract pre 1920 (or perhaps a copy).

I have a few bits to make for it like new clamp bolts for the topslide and a new cross-slide handle. 

And  I have been wondering about a mechanical variable speed drive as well
« Last Edit: October 16, 2022, 05:29:53 AM by BillTodd »
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Offline vtsteam

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Re: 3d printer - Leapfrog creatr conversion
« Reply #31 on: October 15, 2022, 07:29:49 PM »
Wow two nice projects! I hadn't seen the spot welder earlier. I have a Harbor Freight type that looks so similar, but obviously not built from scratch, and probably not as high quality for it.

The lathe is really intriguing. I really like the pleasing base shapes of the tailstock and headstock, which re-finishing has brought out. I wonder what the waisted section of the leadscrew is for? I guess it's a carriage release, but is there a reason for the thread continuation after the break?

The vise/anvil is totally unique and gives it great character, but I'd really hesitate to hammer or bend metal on a lathe ways. On the other hand, it's a wonderful unexpected gadget, and really sets this lathe apart so as a complete homemade object it's very cool.  :thumbup: :clap: :beer:
I love it when a Plan B comes together!
Steve
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Online BillTodd

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Re: 3d printer - Leapfrog creatr conversion
« Reply #32 on: October 16, 2022, 05:00:30 AM »
The waist on the leadscrew was for belt clearance, the previous owner had it mounted on an old sewing machine treadle base . 

Unfortunately I don't know much about the lathe's history. I know the previous owner got it from Davall's (who made flight data recorders ) when he left the firm . He had several patents in his name related to wire handling mechanisms , but I don't think he had anything to do with the lathe's initial construction.I thought it might be an apprentice project, but it seems to have had too much use to be a long term project (and again one would expect apprentices to finish parts).  So, perhaps best guess would be a special project for in-house work when availablity of small lathes was tight.



« Last Edit: October 16, 2022, 05:31:51 AM by BillTodd »
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Re: 3d printer - Leapfrog creatr conversion
« Reply #33 on: October 16, 2022, 06:21:51 AM »
I've just found this old pathe news clip fro 1951/2

https://www.britishpathe.com/video/making-coronation-clocks/query/coronations

The clocks are being made at Davall's  there is the briefest look at some of the machinery , but no lathe ,   only the hint that the handle shape of the machine could be similar to the lathe's

Bill

Offline vtsteam

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Re: 3d printer - Leapfrog creatr conversion
« Reply #34 on: October 16, 2022, 05:11:25 PM »
I wonder if in an old Model Engineer there is some reference to adding a vise to a lathe -- possibly by a correspondent via the Postbag. If there is, it could be the builder.

I bought two homemade small model marine high speed twin steam engines close to 20 years ago, at a model engineering show in nearby Windsor Vermont, supposedly built in Baltimore. Aluminum castings, sleeved. When reading through some old Model Engineers, lo and behold I came across a reference and photos of the original builder and his engines of the same type, and yes, in Baltimore.
I love it when a Plan B comes together!
Steve
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Re: 3d printer - Leapfrog creatr conversion
« Reply #35 on: October 17, 2022, 03:41:46 AM »
Worth a look, I suppose,  but if it was made for factory/development use , the story would be unlikely to make it to a magazine .

 
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #36 on: December 28, 2022, 11:32:01 AM »
Well, I have started, or is that restarted, the liliipad lillipad project, with the intention of getting it done before the anniversary.  I can't believe it was January when I started this thing, nor how much warmer the weather must have been last year.

Updates will follow...

Unless I get distracted...
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #37 on: December 29, 2022, 04:40:45 AM »
Oh , this bloody thing is doomed.  Minutes after posting the above, I started to cough, nose blocked and head started throbbing.

We have a bird flu alert in the area but I have seen no dead birds... Found a dead fly, so maybe it is flyflu....
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #38 on: December 29, 2022, 08:15:38 AM »
Yep - all our 'free range' chicken are incarcerated in a poly-tunnel due to bird flu - non locally but it's a UK wide order to poultry keepers.

Get well soon Bill, but I very much doubt that YOU have bird flu unless you have some hobbies you've not told us about 
Andrew Mawson
East Sussex

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Re: 3d printer - Leapfrog creatr conversion
« Reply #39 on: December 29, 2022, 10:11:57 AM »
Oh I don't know Andrew, I have an almost irresistible urge to perch on the tv aerial...
Bill

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Re: 3d printer - Leapfrog creatr conversion
« Reply #40 on: December 30, 2022, 01:32:47 PM »
I have mgfade some progress...
I've built the main control board with a  pi pico and relays to switch the main 24v and 240vac heater power, monitor the power button, mains fail and printer shutdown . A bank of supercaps will store enough energy to park the axes and write position to the SD card.

The pico will monitor the gcode data passing from the front panel lcd to the octopus printer board and extract gcodes for bed temperature setting .

More to follow when my brain recovers a bit.
Bill