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Hello,

I have a lathe spindle from an Emco 220P but sadly the drawbar threads on the power chuck was damaged during shipping. (Picture of the spindle nose attached) I've since purchased an old...

Thanks, it's great to have some real numbers to work with and to know your thoughts on how they perform. (Or don't !)

I'm trying to pick up a complete Emco 220/320 bed assembly so I can use the...

Hi All,

I'm looking to build a lathe, basically a clone of an Emco 220p.

I already have the spindle / pneumatic chuck closer / chuck from a 220p on the way and I think I've found a turret for...

Apologies, I tried to be clever by linking to the size-specific .pdf but forgot that it doesn't include all of the load information. Here's the full document:...

So I'm looking to build a lathe and I'm basing everything on the Emco Compact 6 / 120 / 220 lathes. I can't just pick up a used lathe as they are too big and heavy for me to bring get into my garage,...

Thank you for confirming, I can get back onto them to resolve the issue now that I know how it should be.

The similar threads have pointed me to this which pretty much answers my question, it looks like the pneumatics have just been unbolted from the spindle:...

Hello all,

Specifically regarding the Compact 6P, although the answer's probably the same for the 120P / 220P - Can the pneumatics for the chuck / collet be easily removed so that a manual chuck...

Hi all,

I have purchased a BK10/BF10 ballscrew support kit from ebay (Just a cheap Chinese unit) and noticed that the bearing in the floating support (BF10) doesn't slide axially. I.e. It seems to...

Yes that's right, my name is Andrew Young - I have that username so that it's never taken, although it is quite hard to read out over the phone.

It looks like used THK KR linear guides are ruled...

Gerry:
Ah I see, I didn't factor in the life of the bearings etc under the additional load. Aluminium only it is then, which hopefully relaxes the rigidity requirements enough for my design to work....

Thank you both, it is helpful to be able to put some numbers down and calculate things. So even if we were to blindly trust that spindle graph (I'll verify it with the seller, there are enough people...

What are the general requirements for steel in terms of RPM and torque - I had always assumed that you could just take very light cuts (Within reason, the chip size still needs to be reasonable) but...

Hi all,

I'm planning a new build and I think I have come up with a general idea of how the gantry will be, but was hoping to get some input on the rigidity of it all.

So first of all, some...

Sorry I meant the G250, don't know why I said G540. They are indeed a single H-Bridge so I mount two to a single heatsink. (Just using a cheap used CPU heatsink as they are a perfect fit)

I've...

I have them mounted on the bottom of the PCB with the tab away from the PCB like you mention. They are held against the heatsink by the PCB alone, as they are in the Geckodrive G540s.

I can't...

I found that the TO-262 version of the IRF540 is better for mounting on the back as the tab is shorter and doesn't get in the way:
IRF540NLPBF Infineon Technologies | Discrete Semiconductor Products...

Success ! I just received the diode pack I needed to fix my FPGA board from Digi-Key (Really impressed with their international shipping) and made the repair. SOT−323 packages are hard to solder even...

Everything was correct in your original post, for some reason I just misunderstood. It didn't help that I couldn't find the app notes that you were referring to in order to confirm the change, but...

Thank you very much Mariss.

I must have misinterpreted the your response from a few years ago when I showed you my last revision and then added R4/5/6/7. I'll get that change made and replace the...

Quick update, I've tried the 10-microstep code from this thread and have tried disabling the standby functionality with no luck.

I just tried switching the two H-Bridges over and somehow blew them...

Well I'm really late to the party, but I thought I'd have a go at this.

I'm using a slightly different approach - I have a Spartan 6 FPGA dev board and have made separate generic H-Bridge boards...

Even with the higher Rds(on), I don't think that the heat generated would be an issue even with a simple / small heatsink - Looking at the G250 shows how little heatsinking is required thanks to...

From Farnell, the 540N is £0.95: IRF540NPBF - INTERNATIONAL RECTIFIER - MOSFET, N, 100V, 33A, TO-220 | Farnell United Kingdom

The 540Z is £1.53: AUIRF540Z - INTERNATIONAL RECTIFIER - MOSFET,N...

Helmut,

The reason for not picking the IRF540Z was cost. £30 is already quite high for a h-bridge.

I picked the 8pin DIP package for the driver so that everything (Apart from the current sense...

Thanks.

I've been looking at some of the components and noticed that some of the ones I've selected are US stock only which means an extra £16 on the order price - I'll change these when I change...

Thanks for the feedback.

I will change the capacitors as you mentioned shortly. I'll also switch to 1W resistors as there was a 0.5Ohm version in that size. I wanted physically larger resistors...

New version:
http://yngndrw.hostilezone.net/uploads/H-Bridge%202.png
http://yngndrw.hostilezone.net/uploads/H-Bridge%202%20-%20yngndrw.zip

Bill Of Materials: (Farnell didn't have 4.7uF 16V...

Hi Mariss,

This kind of feedback is exactly what I was looking for, although I have a few questions about some of the points. I was having some issues with sourcing some of the components hence...

VPH asked me to upload the design files for the H-Bridge:
http://yngndrw.hostilezone.net/uploads/H-Bridge%20-%20yngndrw.zip

Please note that it has not yet been tested.

The MOSFET section...