LARGE 5 X 10 STEEL ROUTER BUILD

[NIC 77]

Hey Ramsey,

Have you been following 1Jumper10's build log?

http://www.cnczone.com/forums/cnc-wo...are-forum.html

Looks like he's making some drive assemblies, similar to your project.

[ramsey321]

Hey Ramsey,

Have you been following 1Jumper10's build log?

http://www.cnczone.com/forums/cnc-wo...are-forum.html

Looks like he's making some drive assemblies, similar to your project.

No I will have to look at that. Thanks

[ramsey321]

No I will have to look at that. Thanks

My wireway came today. I should be able to use this for all three axis's.

[NIC 77]

My wireway came today. I should be able to use this for all three axis's.

Very nice. Where did you get it?

[ramsey321]

Very nice. Where did you get it?

I picked that up at HGR industrial. I got a great deal on it. Great place to find deals on used items.

[NIC 77]

I am planning to reuse the stuff I have from a previous build. I am hoping that I have enough room in it for this build. I think I will, but I won't know until I try to put all the stuff into it. I think I'll have to run some air lines in it as well for the spindle. That's something I'll need some help trying to figure out.

[ramsey321]

I am planning to reuse the stuff I have from a previous build. I am hoping that I have enough room in it for this build. I think I will, but I won't know until I try to put all the stuff into it. I think I'll have to run some air lines in it as well for the spindle. That's something I'll need some help trying to figure out.

Yeah I know what you mean. You need to break it down so it isn't to overwhelming. Once it is broken down you just have to piece it all together.

[ramsey321]

Ok guys I need some more direction. I am trying to figure out where to source my motors and gearbox. Once I have that nailed down I can machine the uprights and move forward. Does anyone suggest a good place to purchase these. I would need good support and instructions as well. Also what is the standard backlash for the gearbox setup for a rack and pinion system? Thanks

[louieatienza]

Ok guys I need some more direction. I am trying to figure out where to source my motors and gearbox. Once I have that nailed down I can machine the uprights and move forward. Does anyone suggest a good place to purchase these. I would need good support and instructions as well. Also what is the standard backlash for the gearbox setup for a rack and pinion system? Thanks

If you go with ClearPath, keep in mind the motor housing and shafts are NEMA sized, so they wont fit in the typical servo gearhead.

[ger21]

Ok guys I need some more direction. I am trying to figure out where to source my motors and gearbox

That depends on what kind of motors you want.
New gearboxes can be pretty expensive.
As for backlash, the lower the better, but the lower, the more expensive. I'd try to stay below 8-10 arc minutes max.

[ramsey321]

Any suggestions on company's that sell good servos and gearboxs that don't break the bank. Keep in mind that I want company's with good instructions and service.

[NIC 77]

Any suggestions on company's that sell good servos and gearboxs that don't break the bank. Keep in mind that I want company's with good instructions and service.

If you're talking about buying a servo with a gearbox attached as a unit, or even sold together as a kit, I don't know where you are going to find that at a reasonable price. Perhaps someone else knows of a place.........

But buying them separately, good instructions and service could benefit you for sure in the servo department. I'd be looking for reviews on the 1kW Ebay servos, if I was going to delve into the world of servos, as I haven't actually built a machine that used one. As Ger pointed out, the service and instructions would be lacking compared with other options.

So if that is a requirement, you have only one good option of which I am aware, and that is Ger's earlier suggestion:

DMM | AC Servo Motor | AC SERVO DRIVE | AC SERVO MOTOR | ROTARY ENCODER

11A-DST-A6HK1 is the 1kW model for use with their DYN4-HO1 driver.

It's rated speed is 1500 RPM with a max speed of 3000 RPM. That means the continuous output power drops off a bit past 1500RPM, but you could still run it continuously at 3000RPM. That's a bit confusing if you compare it to rated power output vs max power output, not the same things because you cant run on max power output continuously, but you can run at max speed continuously.

Power graph is in the manual on page 10:

http://www.dmm-tech.com/Files/ACSMTR-G1-0815A15B.pdf

So looking at the power graph, I'd be looking for my 1800 IPM at around 2400 RPM which would give a peak power available of around 10MW.

Now on to the gearing, to be purchased separately:

If you use the same size pinion radius as 1Jumper10 is using on his build, pitch circle diameter is 39.79mm, that gives you at 2400 RPM:

1181 IPM at 10:1
1687 IPM at 7:1
2362 IPM at 5:1

7:1 is the best choice for reduction using this pinion size.

Either at McMaster Carr for a regular pinion or at Atlanta Drives, for an ISO A-63 flange, the maximum pinion pitch circle diameter I can find for 20 degree pressure angle rack (is that what you're using?) is 2 inches, which gives:

1257 IPM at 12:1
1507 IPM at 10:1
2154 IPM at 7:1

You'd have to push to near 3000 RPM, which is not as good on the power curve to get your 1800 IPM with 10:1, but you'd gain a little with the extra reduction. Here, I think 7:1 is again your best option, but you could also use 10:1.

So you need to find a gear reducer with 19mm input and a 145mm bolt hole circle that either has 7:1 or 10:1 reduction to use with the DMM 1kW servo. Any good quality one will do, service and support isn't an issue unless you want a warranty, and then I'd think the price will double. A right angle reducer would be ideal.

I'd start by sending an email to DMM and asking them for a list of compatible gear reducers for this servo.

Then I'd look through the list of manufacturers that someone posted earlier. Go to their websites, find catalogs, find part numbers, that match the 145mm bolt circle and 19mm input, then search those on EBay. Also search Aliexpress.

Good luck.

[ramsey321]

If you're talking about buying a servo with a gearbox attached as a unit, or even sold together as a kit, I don't know where you are going to find that at a reasonable price. Perhaps someone else knows of a place.........

But buying them separately, good instructions and service could benefit you for sure in the servo department. I'd be looking for reviews on the 1kW Ebay servos, if I was going to delve into the world of servos, as I haven't actually built a machine that used one. As Ger pointed out, the service and instructions would be lacking compared with other options.

So if that is a requirement, you have only one good option of which I am aware, and that is Ger's earlier suggestion:

DMM | AC Servo Motor | AC SERVO DRIVE | AC SERVO MOTOR | ROTARY ENCODER

11A-DST-A6HK1 is the 1kW model for use with their DYN4-HO1 driver.

It's rated speed is 1500 RPM with a max speed of 3000 RPM. That means the continuous output power drops off a bit past 1500RPM, but you could still run it continuously at 3000RPM. That's a bit confusing if you compare it to rated power output vs max power output, not the same things because you cant run on max power output continuously, but you can run at max speed continuously.

Power graph is in the manual on page 10:

http://www.dmm-tech.com/Files/ACSMTR-G1-0815A15B.pdf

So looking at the power graph, I'd be looking for my 1800 IPM at around 2400 RPM which would give a peak power available of around 10MW.

Now on to the gearing, to be purchased separately:

If you use the same size pinion radius as 1Jumper10 is using on his build, pitch circle diameter is 39.79mm, that gives you at 2400 RPM:

1181 IPM at 10:1
1687 IPM at 7:1
2362 IPM at 5:1

7:1 is the best choice for reduction using this pinion size.

Either at McMaster Carr for a regular pinion or at Atlanta Drives, for an ISO A-63 flange, the maximum pinion pitch circle diameter I can find for 20 degree pressure angle rack (is that what you're using?) is 2 inches, which gives:

1257 IPM at 12:1
1507 IPM at 10:1
2154 IPM at 7:1

You'd have to push to near 3000 RPM, which is not as good on the power curve to get your 1800 IPM with 10:1, but you'd gain a little with the extra reduction. Here, I think 7:1 is again your best option, but you could also use 10:1.

So you need to find a gear reducer with 19mm input and a 145mm bolt hole circle that either has 7:1 or 10:1 reduction to use with the DMM 1kW servo. Any good quality one will do, service and support isn't an issue unless you want a warranty, and then I'd think the price will double. A right angle reducer would be ideal.

I'd start by sending an email to DMM and asking them for a list of compatible gear reducers for this servo.

Then I'd look through the list of manufacturers that someone posted earlier. Go to their websites, find catalogs, find part numbers, that match the 145mm bolt circle and 19mm input, then search those on EBay. Also search Aliexpress.

Good luck.

Thanks for the info. I did talk to DMM they recommended sure servo. I just wasn't sure about the quality. I know Atlantic sells some really nice stuff but it's super expensive. I am using a 20 degree rack.

[ger21]

Unfortunately, it looks like when you get into 1Kw servos, there's no such thing as an inexpensive gearbox.
I think it would be cheaper to go with a larger servo and use a 3:1 belt reduction, unless you want to spend upwards of $500-$700 each for gearboxes.

Or figure out exactly what you need, and wait patiently for some to appear on Ebay.

[louieatienza]

I don't think even 1kW is necessary. First, you're driving the gantry from both sides. Second, you're rapiding - a 750W servo will run peak about 2.4kW; at most it would take about 6 seconds total to traverse the entire long axis at 1000ipm. Lastly, you should consider the pinion itself as a gear increaser or multiplier (and thus a torque reducer); so if you run a 3:1 reduction and use a pinion with a 1" pitch diameter, you'll have less torque on the load than if you direct-drove a screw with a 1" pitch.

[NIC 77]

Or figure out exactly what you need, and wait patiently for some to appear on Ebay.

That's what I would do.

I'd start reading through the Alpha Wittenstein catalogs and become familiar with their products. There are always deals on alpha planetaries to be found on EBay. There are always people who want too much for them, but those don't sell.

When I bought the one I have, I wrote the person up (and actually it was an add from a company that does asset liquidation) and I said I liked the gear but your price is too high, and I made him an offer for half, and he said let me check on that. Called me on the phone to say OK.

Ramsey,

1:7 and 1:10 are popular Alpha ratios. 19mm input is popular. Also, if you got one with a larger hole than 19mm, you could have a friend with a lathe (or perhaps you have a lathe) make an adapter. Failing that, Alpha makes adapters.

They also make adapter plates. Which is why when you order from them directly, you can specify what motor you have.

Like this:

https://www.nriparts.com/power-trans...placement-part

and this:

https://www.terapeak.com/worth/new-a.../291240709367/

If you have a cnc machine running at the moment, those would be easy enough to make.

Here's a good tip. If you go to the Alpha website and choose one of their product lines, in this example speed plus, and click on CAD it should take you here:

Object reference not set to an instance of an object.

At the bottom it lets you choose your motor. Find a motor that's on their list that has 19mm output and a 145mm bolt hole circle and the same shaft length. That will take a bit of digging but I'm sure you can find one from the long list they have.

After you choose it, it will tell you the exact ordering code for any adapter plate or bushing you need, and you may find it online like the links I posted above.

2nd good tip. Some people don't know how to put stuff on EBay so others can find it. The words "alpha" or "gear" might not even be there. Learn about the products and search by the first part of the product code, for example "tp 025" is one of their codes. It's really simple once you get the hang of it.

Alpha Gear, EBay, do it! Happy hunting.

[ger21]

750w DMM's with these 10:1 gearboxes are reasonably priced.

Nema24 36 Servo Planetary Gearbox Ratio 80:1 50:1 40:1 35:1 25:1 20:1 10:1 5:1 | eBay

These servos can be run at 4500rpm, which should give you plenty of power, with the 10:1 ratio.

[ramsey321]

750w DMM's with these 10:1 gearboxes are reasonably priced.

Nema24 36 Servo Planetary Gearbox Ratio 80:1 50:1 40:1 35:1 25:1 20:1 10:1 5:1 | eBay

These servos can be run at 4500rpm, which should give you plenty of power, with the 10:1 ratio.

Here is what DMM said about sizing motors for my machine.
Hello Scott,

The 1.0kW motors would be a good size and you will need a belt reduction as well since the gantry is quite large. You will need to use the smallest diameter pinion, the 1.0kW motor has a 19mm diameter shaft, so assuming you pinion is 27mm diameter, with a 5:1 reduction, the load capacity is 1300kg. This includes the gantry mass, friction and cutting forces. Our calculations are very conservative so this will be a good size for the machine.

This set up puts you at ~1980IPM rapids @ 3000rpm from the motor so you have a little more headroom in speed as well. You can use any reduction ratio from 5:1 or higher. For example, 8:1 reduction puts you at 1200IPM, but the load capacity increases to 3,300lbs per motor. A smaller diameter pinion will give you more power and lowers the speed as well, but it's difficult to find anything smaller than 27mm diameter that can support these forces.

For the Z axis, we recommend using a smaller pitch ball screw as it will give you much more precision and smoothness. With a 20mm pitch ball screw, our 750W motor direct drive will give you 270lbs load capacity. This will be no problem for your 200lbs gantry. But the speed capability is quite high at 3900IPM @ 5000rpm from the motor and the Z usually does not need these high speeds so we recommend using a smaller pitch ball screw to get more headroom in power. For example, a 10mm pitch will give you 1100lbs capacity @ 1900IPM rapid, which should still be plenty fast, but will run much more rigid and smooth.

We size machines very often so can guarantee you will have no problems with these numbers in general. Let me know what you think.

[NIC 77]

But the speed capability is quite high at 3900IPM @ 5000rpm from the motor and the Z usually does not need these high speeds so we recommend using a smaller pitch ball screw to get more headroom in power. For example, a 10mm pitch will give you 1100lbs capacity @ 1900IPM rapid, which should still be plenty fast, but will run much more rigid and smooth.

1900 IPM raid on a Z axis?

[NIC 77]

So if you've been following 1Jumper10's build log, I now include inertial effects in my performance estimation. The "I" or inertia values of 0.0002 and 0.0004 kg*m^2 are properties of the reducer gear and we don't know what they will be yet. From what I've seen, for the power output required, the required gear will have a value in this range.

The estimation does not include:

Cutting forces, extra acceleration required for backlash compensation, etc, etc. not included. Any mistakes that I may have made may be unaccounted for also. I'm fairly confident but have not been fact checked by a second party. I came up with this yesterday and was fine tuning it today. I changed one small thing from yesterday to include the inertia from the reducer in the optimal gear ratio calculation, which is something I missed before.

I think the advice you were given by DMM is good, but rushed. I actually took the time to make the graphs. You're welcome.

Feel free to invite the person from DMM to come and look at this thread. I wouldn't mind that.

And I think 1900 ipm on a Z is more than excessive. Your Z would work with a Nema 34 and a 5mm pitch ballscrew up to a speed that any sane person would run it at. Or perhaps I'm wrong?

The clear winner for 1800 IPM is the 7:1 at at 2 inch pitch circle diameter. That is about 0.35G above what the advice you were given according to my graph. Next is 7:1 at 39.79mm pitch circle diameter.

My spreadsheet shows the optimum Gear Ratio based on inertia. Pinion size and gantry weight change this ratio the most.

For 5:1 - 27mm the optimum was between 5 and 6
For 7:1 - 39.79mm the optimum was between 7 and 8
For 10:1 - 50.8 the optimum was between 9 and 10
For 7:1 - 50.8 the optimum was between 9 and 10

I'm guessing that means that all of those options have good inertia matching and that you don't have to worry about over or under shoot or any strange effects like that.

750w DMM's with these 10:1 gearboxes are reasonably priced.

Nema24 36 Servo Planetary Gearbox Ratio 80:1 50:1 40:1 35:1 25:1 20:1 10:1 5:1 | eBay

These servos can be run at 4500rpm, which should give you plenty of power, with the 10:1 ratio.

I was thinking about this earlier today. A 750kW with a larger reduction ratio. I was thinking of 16 for some reason. They can go up to 5000 rpm. I had to get the manual out again to pull the numbers for these graphs .

The only concern I have is I can't see any data on those reducers as far as input speed or continuous / max load output. Perhaps I missed it?

I wouldn't buy one without that information.

If you look at this gear for example:

Gear Reducers | In-Line | PE-N34-010G | GAM

It's on a Nema34 frame and it has a max acceleration output torque of only 24 Nm. It wouldn't last too long. Not sure about the other ones. If you knew the weight of them, you'd could have an idea of the load capability........

I'm out for the next few days. Tired of graphs, much work to do. Talk to you guys later. Good luck Ramsey with whatever you choose. I'm sure it will be fine.