[peteeng]

Hi All - All the small parts are now painted. Painting the edge of the two bases and I can start assembly... I( organised the bench's so I can start building the bases on them as well. Peter

[peteeng]

Hi All - Got one of the machine bases painted today. Its raining so the paint is not curing as fast as I'd like. I usually can get 2 double coats on quick sticks. So the other base will be after Christmas. All out there have a great and safe Christmas Ho Ho Ho Peter

[joeavaerage]

Hi,
raining in NSW in summer is a good thing, a great thing, Santa is treating you with every drop that falls!

Craig

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Hi,
raining in NSW in summer is a good thing, a great thing, Santa is treating you with every drop that falls!

Craig

[peteeng]

Hi all - I put this here so I can find it again - Peter

Heres a really good article on HSM - Peter Santas peeing on the roof again....

A Machinist’s Guide to Trochoidal and Peel Milling – Make It From Metal

What High Speed Machining Is And How You Can Do It – Make It From Metal

How to Machine Aluminum: All You Need to Know – Make It From Metal

Yippee - I can start assembling - Peter

[peteeng]

Boxing day Hello to All - I use formply for a lot of things. The surface is a brown phenolic coating designed as a non stick surface. So gluing this stuff has always been a concern. I have tested a few glues and I abrade the surface. I prefer single pack glues to epoxy, although epoxy is the best. I tested some Gorilla PVA glue on the formply. I abraded the surface with 120grit (random orbital sander) then wiped it down with a wet rag. I applied the glue to the cut edge and a smear across the phenolic. I also placed a dob on the surface so I could check its cure by seeing its gone fully clear. 2 days after gluing I clamped it and broke it and the gorilla glue tore off the top plies, so I'm happy to use it. Onward to assembly. Peter

[peteeng]

2024 is nearly here! - Today I built machine base no1. Came together nicely. Now to No2... Peter

[peteeng]

Hi all you lot - Nema34 upgrade - I have intended to use a Knighthawk controller with 80V drivers on this build. This was to achieve better speed, one aim with this design was for it to be very fast. I was also going to use N23 motors with 5:1 gearboxes to achieve better torque but then I'd lose speed. Another thread has covered this and this has made me review the N23 choice. So looks like I'm going up to a Nema34. This gives me the 8Nm at speed, no loss in the gearbox (90% efficient) and the 14mm shaft for the pinion. Now I'll have to look at the geometry consequences... The N23 is 2.3" square the N34 is 3.4" sq so have to check it fits.... I'll have to use the geared motors I have on another build.... Peter

[joeavaerage]

Hi peteeg,
I don't know whether you saw this motor in response to another thread. It a 34 size stepper 4.5Nm but only 2.5mH inductance. Even with only a 60VDC driver it retains 67%
of its torque at 700rpm. I could well imagine that it would do 50% (or better) or 2.25Nm at 1000rpm with 80VDC up its chuff.

https://www.omc-stepperonline.com/p-...s-34hp29-6004s

Okay, so it's less than your 8Nm, but with it low inductance its potential speed is very good indeed. It's the best overall performance curve that I've ever seen in a 34 size stepper.

Craig

[peteeng]

Hi Craig - Yes I saw that in the other thread and that's what made me review the design. I have used the N23 gearboxes on a router and they run really smooth. But you pay the speed penalty. Seems N34 is the go at 80V. Have to check space for the 3.4" base vs the 2.3" flange but since I have not committed to the final gantry design I think it will work. But I'll get to that later. I want to finish Lanky's bases and walls then finalise the rest... Peter

note: with a gantry machine most people buy the same motors for the X and Y. But the Y is two motors so you can save a little bit of $$$ by downsizing the motor as you have 2 of them. Plus this reduces the load on the PS. So I use as small a motor on the Y axis (x2) then try to match the X with the bigger motor... But sometimes the bigger motor costs the same so you get the bigger motor all round.... P

edit: look like I can squeeze it in

[peteeng]

Hi all - So looking at the N34 closer and remembering Lanky is a R&P machine with a 20T direct drive pinion means that at 500rpm its moving at 42m/min which is fast but it has about 4Nm torque. Its also only going to have 31kgf at 500rpm so the equation is biased to speed. At 500rpm the N23 with 5:1 gearbox is moving the system at 8.3m/min which is fast enough for this machine and its force is 33kgf at 500rpm (100rpm at the pinion)... So the forces are similar but the N34 will be operating at a low speed most of the time. Steppers don't like that... prefer to keep them spinning a bit... so maybe the N23 is the go.... I'll have to look at it closer.. The drivers are the same 80V 7A for both. DM860 - anyone used the DM860? any comments? HNY Peter

[joeavaerage]

Hi peteeng,
yes, I rather agree the N34's would be a bit wasted really, more speed than you 'can shake a stick at' but very modest thrust. If you could do a 2:1 or a 3:1 reduction then the N34's
would be fine, but that rather defats the point of going to direct drive. None the less those N34's (4.5Nm 2.5mH) are good enough to' put a horn on a jellyfish'.

My first mini-mill had low lash 10:1 planetary gearboxes mated to Vexta five phase steppers. Despite being small they were very good......albeit with slow rapids, 1200mm/min.
In a machine of 180mm x 180mm x 180mm travel it was not a deal breaker but would be a major drag with Lanky.

It was what inspired me to get servos for my next mill. No matter how good the Vexta five phase steppers were, Delta servos put them to shame!.

Craig

[peteeng]

Evening all & sundry - Finished the No1 base today. Now onto No2... Came out very flat. The cabinet maker I use to cut stuff always cuts accurate and flat. His CNC table saw must be a cracker. I'm happy I went with the water based adhesive, so easy to clean up the squishout... and you can't live without forceps. Thanks to Dr Oscar Allis and others. I like my mosquito especially. Now to add the feet and the M8 inserts.... HNY... 2023 is all over red rover---- Peter

Hi Craig maybe time to look at servos for Lanky...

[peteeng]

Evening all after a slight interlude - Base No1 is done and set on Bench No1 now onto Base No2 - I also have to install all of the hold down inserts....The base reminds me of the Batmobile. Peter

[joeavaerage]

Hi,
yes servos are great, but still not cheap, at least for dependable quality ones. Take a look at these 400W Deltas, this guy is selling a set of four for $700USD, which is good buying,
and these are barked units and would ordinarily be another $100 to $150 premium each over new price.

Craig

PS: Sorry mangaed to forget the link to the thread:

https://www.cnczone.com/forums/for-s...or-driver.html

[peteeng]

Hi All and Sundryites - Today I started installing the thread inserts in BaseNo1 and started looking at the Wall assembly. Peter

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Hi All and Sundryites - Today I started installing the thread inserts in BaseNo1 and started looking at the Wall assembly. Peter

[peteeng]

Rounded up the day with all inserts into BaseNo1..Got to get more screws to start No2 Peter

[peteeng]

Evening all you lot - Got into Base No2 today. batman would be pleased. https://www.youtube.com/watch?v=DKq4uoGdnFw The second one always goes faster then the first one. I'm keen to get into the walls. Peter

[peteeng]

Hi all - Finished Base No2 today Yippee,,, , onward to the walls. Peter

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Hi all - Finished Base No2 today Yippee,,, , onward to the walls. Peter

[peteeng]

Hi all- I have placed Base No2 onto its bench and now to drill the hold downs. Then onto the walls. Its going to be BIG! Peter

[peteeng]

Hi All - Lanky has stalled over the last month or so for various reasons. But I've preped the walls for painting, now can assemble. The formply is coated in a phenolic film so when used for concrete formwork it releases easily. This also means paint may not stick. So I did a quick test. One end of the board is sanded with 60 grit the other is plain. Well the plain end paint comes off really easy and the sanded surface sticks. So for you guys out there building concrete machines think about using formply!! for moulds. I start assembling walls today. Yeh Lanky's moving again Peter