Minnetonka, Minnesota Primo Build

Mostly Printed CNC - MPCNC Your Builds
101

More to troubleshoot… I have three FluidDial pendants. All are reliable.
I’d start double checking wiring on your pendant.
Be careful about connecting/disconnecting the pendant.
Never do that while the Jackpot is on, and be aware of ESD when you are connecting or disconnecting the pendant. Bart and Mitch have noted ESD damage to the ESP-32s on either side of the system. There is some rudimentary ESD protection in the Tindie kit which you won’t have with a hand-wired harness.

Yes it should be.

Think about your strategy for managing usb connect/disconnect cycles. You may want to get a USB hub for that. Since you intend to use the USB connection for gcode sending, you may want to consider a data-only cable. That way it’s impossible to forget and turn on the ESP-32 without first turning on the Jackpot.

You’ve buried your ESP-32 down inside your case, I wonder how much attenuation you are getting from the enclosure.

There are ESP-32s that have external antennas if this proves to be a big challenge for you.

Community support works great.

You’ve put a bunch of hard work into a great looking machine build.
I’m looking forward to seeing you get some projects coming out of that thing.

102

Jim

I ordered a USB power blocker dongle that should prevent power from going to the ESP from the USB cable.

https://www.amazon.com/dp/B094FYL9QT?ref=fed_asin_title&th=1

Also, I had the TX and RX wires switched from the get-go so I likely gave the m5 dial a gremlin that is popping up from time to time. The screen glitches at times too. So I’m going to order a new kit from Bart to get a fresh start.

103

ITS ALIVE!

Thanks everyone for all the help and encouragement.

I’ve had this moment in my brain for 4 years and today my eyes got to see it for real!

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It’s Alive Video

The first thing this robot had to make was a test lid for the control panel. That went great, so the expensive plexiglass was used, and it worked out just as planned.

I was conservative with feeds and speeds as well as a very shallow .2mm depth of cut. I wanted to have a happy first cut and not break a bit out of the gate.

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104

That won’t hurt anything.

This, on the other hand, points to something being wrong. Likely wiring related.

Woo hoo!
Congratulations on getting your machine up and running!

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105

Jim

I trust your opinion here: I’m using a Powerstat l116c 0-140v 10 amp variable Autotransformer (variac) to control the RPM of the Frued FT750 Router (old non-variable speed with brushes 120v 60hz 6.5amp 27,000 rpm. Using a tachometer I determined the router RPM at given volts and made a dial for the variac to see that rather than the volts.

My question is do you have an opinion on this?

In general, all variable speed routers use some sort of voltage control or regulator to vary the speed (rpm) and this variac has got to be more robust than anything inside a new router. THe variac weighs about 20 pounds and most of that is the copper coils inside the thing.

I know I’ll lose torque at lower volts (rpms) but If I hear the router struggling I can just turn the dial and instantly increase the rpm’s.

Anyway, I’m not sure I’ve seen this on an MPCNC before so I was curious about your thoughts.

For the first two (real) cuts I ran the bit at 20,000 +/- rpm (2 flute compression bit) for the hardboard and at 15,000 rpm (single flute Amana plexiglass bit) and it was super nice to have a big (speed) dial to adjust on the fly rather than the tiny dials on a router.

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106

My guess is that you used things you had on hand to build your machine which included the Frued router and the variac. If that’s working well for you, then that’s great and keep using it.

I’d never go out and buy that combo, I’d rather put the money into a really good trim router or a spindle/VFD. There’s plusses and minuses to either of those, but overall is a much cleaner setup and probably less expensive and easier to use once installed.

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107

You guessed it. I used stuff that was already on hand. As the saying goes, “Necessity is the mother of all inventions.”

I’ve been keeping an eye out online for a VFD/Spindle combo for sale. I am also looking at them on Aliexpress and other shipping from overseas sites. I need to be sure that they are for 110volts though.

Also curious about the weight difference between the trim router and the VFD I’m wondering if the z-stepper motor gets too stressed.

108

The LR series is very well designed for using the trim routers, and this works really well.

Spindles are a mixed bag- some love them, some struggle horribly with them.

If I were going to use a spindle, I get get an air cooled one, using a VFD that has an RS-485 interface.

Frankly, though, I have Bauer and Kobalt trim routers and find in my own setup that my dust collection (shopvac) is way more irritating than the trim router from a noise perspective, so for me at least there’s no real benefit to the spindle.

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109

Like Jim, router noise isn’t a big deal for me.

The only reason that I would consider a spindle over the Makita (and Kobalt) trim routers that I am using now is because the spindles can run at lower RPM. This is an advantage for using larger diameter tools, and cutting harder materials. Lower RPM makes for bigger chips and less friction heat. Even at a #1 setting both the Makita and Kobalt are relatively high RPM tools.

So a Makita RT0701C at a setting of “1” is about 8500-9000 RPM. Consider that some spindles have a MAXIMUM speed of 10,000 RPM, and that puts the lowest speed of the trim router within reach of tghe highest speed of many VFD spindles, and full speed (6) is close to 30,000 RPM, like 3 times the rate.

For cutting products like plywood, MDF, OSB, or particle board, the high rates are helpful in making for nice edges. Softwoods also get some benefit from the higher speeds. This makes things like edge bevels (That we would NORMALLY use a trim router for) quite functional and low effort on the part of the user, and even for hardwoods and harder material like countertop coverings or the like.

Me? I’ll stick with the lower cost and ease of a trim router.

As for the weight…

If we take an 84 oz.in motor, and put it on an 8mm lead TR8 leadscrew, assume we limit the motor current to 40% (800mA) thus limiting the torque similarly…

40% of 84 oz.in is 33.6 oz.in of torque. At a distance of 1" from the center it applies 33.6oz of force. A 1" radius circle is 6.28" of linear distance, but we’re only going 8mm with a 4 start TR8 screw, so we basically multiply that torque. 6.28" is 159.5mm, so we multiply by 159.5 and divide by 8, giving us a force of 669.9 oz, or just under 42 lbs.

Now, that’s what the motor can HOLD, and not necessarily LIFT, and includes the core, Z tubes, tool and mount. The amount of lifting force it can handle is that less the amount it’s actually holding, so your acceleration setting should take that into account. My core and Z tubes are under 4 lbs, so there’s plenty of lift left over at 800mA current.

Of course a LowRider has about twice that lifting power, though it has a heavier gantry to also support.

I think the tl;dr of all that is “Dont’ worry about the weight too much.”

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110

Thanks for the comments, everyone. I don’t think I’ll end up pulling the trigger on a spindle though.

Likely 1 of 3 things will happen:

  1. I get bored with this hobby and the machine sits idle collecting dust.

  2. I use the machine a fair bit and the Freud Router is showing signs of wear, then I will replace it with a new trim router ( I have another Freud I bought as a spare and a Dewalt dw611) so I have options in-house already.

  3. I love this hobby even more and use the heck out of the machine making tons of stuff & want to upgrade to a more pro-level machine Onefinity, Longmill, Avid, etc. If this machine can make enough money for me to buy an upgraded one then that’s a win-win in my books.

a 4th longshot option might be to upgrade this MPCNC to an LR4 but honestly at that point I think I’d rather save and get a pre-built machine.

111

Here’s a night time picture showing the Glow in the Dark PLA components.

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112

I hope that’s an outcome where you enjoy using your machine and it inspires you to do more.

Just to say it out lout- a properly built LR4 is in fact a pro level machine.
We have plenty of community members running businesses with it.

It isn’t a $100,000 or $1M commercial machine, but in terms of capability per dollar- I believe you’d find the LR4 near the top of the heap.

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113

Yes from what I see the LR4 is a competent machine.

In general, under the scenario where I want to take the next step up from the Mpcnc, I’m keeping all options open on the “imaginary” table.

I’ve been looking at many different “consumer” grade CNC machines.

I like what I see in Stepcraft series machines.

I like what I see in Onefinity Machines

I like what I see in Sienci Labs

I would consider the above to be in the ballpark of midlevel consumer machines in terms of cost

Above that would be the Avid ecosystem and many other more expensive systems.

My general feeling is that some of those systems require less (user assembly) than the LR4.

And rather than rely on the generosity of end users (V1-Engineering user Forum) purchasing a stock machine from a company should get me technical support directly from the company.

There will always be “user forums” no matter the platform, However, if I’ve moved past the MPCNC’s capability I’ll likely want to have dedicated direct to the manufacturer support.

I did not mean to imply that the LR4 was not capable, it’s more to do with assembly and end-user support from the manufacturer.

114

The starting Onefinity is 3,300
The starting stepcraft is 2000
You can buy an assembled LR4 for 1000

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115

Yes, but at the point where I pull the trigger on “THE NEXT” cnc it’s likely that it will be because the machine will be “making money” for me and in that case a 1k or 2k difference in “purchase” should just be factored into the per item sale price to recoup that difference. IE If you increase the price of Widget A by $1.00 per item and sell 1,000 widget a’s to recoup a $1,000 purchase price etc.

In general at that point it would be a business investment versus a hobby purchase.

Once we move into the realm of business investment then there are more factors to consider than initial purchase price.

116

It’s all moot at the moment though because my current MPCNC Primo has only been operational for a few days.

117

Regardless of your future replacement plan, that is a sweet machine build you have.

I just cannibalized my primo to make a lowrider 4 for a friend and have now a different LR 4 in its place. With the small space I had, the cable chains on the perimeter were more limiting on the mpcnc than the lowrider. I prefer the workpiece access on the lowrider as well.

The MPCNC is very capable. Keep an eye on the core mounting bearings as mine had a tendency to loosen with use.

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118

Indeed but in this hypothetical if you’re talking about production then your onefinity needs to produce widgets more than 3x faster than 3 low riders to make it worthwhile doesn’t it?

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119

Ohhhhh snap, so if the lowrider is a glowrider, what is the mpcnc??? That is sharp!

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120

I just tore my mpcnc apart and converted. You already have the jackpot, so cost would be minor!!! Just sayin :wink:

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