3d printer - Leapfrog creatr conversion

[Btje]

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?

[BillTodd]

 Hi Btje, welcome to the forum 

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. 

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 

[BillTodd]

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

[BillTodd]

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.

[awemawson]

That’s looking a whole lot more wholesome Bill 

[BillTodd]

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

[vtsteam]

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. 

[BillTodd]

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.

[BillTodd]

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

[vtsteam]

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.

[BillTodd]

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 .

 

[BillTodd]

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...

[BillTodd]

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....

[awemawson]

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 

[BillTodd]

Oh I don't know Andrew, I have an almost irresistible urge to perch on the tv aerial...

[BillTodd]

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.

[BillTodd]

My aim is to get the printer running again in November.


I now have the bed debugged and the 9 way pid controller working

The solid state relays are mounted on the underside of the bed. Three max335 spi controlled switches multiplex the thermistors back to the Pico ADC and switch the SSRs.

[BillTodd]

Not a big update but at least posting here helps to keep me focused...

Pico is now telling Marlin the bed temperature by faking a thermistor (using a PWM pin ) and reading the target temperature from the status report. The LCD asks for an update every second or so,  Marlin responds with temperature and targets  . The pico sniffs  the rx and tx lines and parses the data to Extract the bed temperature.

Still work to do. The solid state relay that was supposed to power on the main 24v smpsu went pop immediately, too much surge current.  The fake thermistor needs better filtering .

Overnight thought... The fake thermistor is faking the wrong type of thermistor . I remembered that the leadfrog bed uses a different thermistor. On close inspection, the SSR didn't pop , I had wired the PSU to the heater out relay so what I thought was a pop was just the relay momentarily engaging as the power was cycled. Long story short, it's working fine.

[BillTodd]

Bed now controlled from Marlin on the printer

[BillTodd]

This is going well... (should I have said that?)

The bed control software is working well , I've a couple of incidental hardware issues to fix .

Today i decided to align the bed : first the rails were trammed using a inclinometer  (aka gunners quadrant) - these super accurate adjustable levels , it can easily detect a piece of paper (3 thou") inserted under one end of the bar shown , I'm confident I got the two rails planar to better than 50um.

Tramming the bed-frame was a fiddle , I could level the two front ball-screws using the toolhead mounted DTI , I had to use the Inclinometer for the rear one.

leveling the bed segments was (as mentioned above) a right PITA .  I had to trim the tabs of a couple of panels to get them to sit flat with the meeting panels before I could adjust it. Once all the panels were close to zero , so there was a little less interaction between the adjusters ,it was possible to get it flat to better than +/-50um .

If I were to do this again , I'd make the plate from a single sheet and just cut thermal relief slots between segments.

[BillTodd]

This is going well... (probably should not have said that)

I had to rewire the mains connector because the wires were an inch too short. Interestingly the  'as used in the school from where I bought it' , wiring  was arse-about-face !   

  I'd had a couple of minor buzzes from the thing while it was switched off and was a little puzzled as to why. The live and neutral was swapped on the IEC connector so that the switch was in the neutral side !

[BillTodd]

It's going ..

Well, I really should not have said that.

However, once dialed in the first layer was quite good, and until the extruder seized and the part cooler fan refused to start without a flick , it was looking like a printer again.

[BillTodd]

After a fight with Marlin's config and a string of adhesion issues , I have almost managed to print something 


A typical  Benchy 

The bottom third looks ok-ish Then , after adjusting the cooling , the hot-end faulted with a 'runaway' error (the original cooling fan broke so i was running a bodged up thing ) 
It resumed the print but reset the 100% flow until I noticed. Unfortunately, I tweaked the speed down to 95% instead of the flow and scratched my head until I noticed  . By then it was a complete mess so I wound the speed up to 200% ...   

and spat it off the bed . 

[BillTodd]

I have a benchy, it's crap  - no cooling - but it was started from cold without intervention and it completed  .

[BillTodd]

With cooling (I just glued in a new fan to the old duct) , the benchy is a lot more wholesome . Still some shrinkage at the bow and overhangs are poor (needs more cooling )  . There's a bit of stringing - temperature?. Maybe a bit of under extrusion too (might be cooling , it is worse at the back side of the extruder) .   Corners are a bit bulgy I may have to pick your brains about pressure advance etc.  If you squint, you can just about make out something, something, benchy on the stern . base shows a little bit of curling, but the painted surface is not great for adhesion.