Gunhead CnC lathe.

[Brian37]

Hello.

I'm new here and I thought you guy's would be the people to ask about this lathe. I'm looking to buy a new mini-lathe and I've been looking at Gunhead's because of the price, ($1400) which doesn't seem like its too expensive. Has anyone bought one of these, and is it worth it for the price? Some people have said that Gunheads a good manufacturer but I cant seem to find alot of comments about them to really make up my mind. I plan on using it for pen turning and other projects, so if anyone here can help me decide if its a good lathe for the price let me know.

Thanks guy's.

fyi http://gunhead.com/GMW/index.html

[RotarySMP]

Funny marketing. "We invented this CNC lathe..." There is nothing there which hasn't been done by dozens of people.

On the one hand, that seems like a lot of money for a couple of rolled ballscrews with anti backlash nuts (about $300 worth) with $200 worth of steppers and drivers, and about $50 worth of break out board, and spindle interface. That means you are paying about $850 for a couple of aluminium motor mounts and mounting parts.

On the other hand, they look like they have things running about as well as you can expect from a 7x. They look like they have matched the motors drivers and leadscrews well to the machine.

You have to wonder how bolt on this is. The Sieg 7x are not exactly accurately machined. How do you locate the holes at the end of the bed?

I don't like the layout. They add a lot of length and especially width to a compact machine.

I did my 7x first conversion nearly completely on the lathe itself. Since then I have changed some bits with milled parts.

Bolting on motion control does not address some of the machine basic issues.

Replace the chinese bearings (I haven't done the tapered roller bearing mod, but it is supposed to reduce chatter).
Correct the variable bed thickness.
Increase cross slide travel.
Put on a more powerful motor etc

[RotarySMP]

Ask Gun heads to provide a video of it parting off three inch stainless bar stock.

Unless you have no space for a bigger machine (like me) I would recommend you get something 10x or bigger. They are much better lathes.

[Brian37]

I don't want to pay too much for a kit either. So, I did a little research.

I decided to add up all the various costs:
-As you said, $300 for leadscrew and anti-backlash nuts
-$320 for two 100 dollar gecko drivers and two 60 dollar motors (looked it up.)
-$50 for breakout board and related components
That's $680 for the base components.

For all the other things I need to make an equivalent Lathe to Gunhead's:
-I found a nema4 enclosure for $70 with backplate
-AC power receptacle $20
-Bearings $100, for what I need
-Need a power supply for the geckos/motors, that's about $60
-Cheap e-stop on ebay, about $20
-Limit switches and mounts for them, $50 (just guessing.)
-Shaft couplers $80, let's say 4, one for each motor and one for the
leadscrew on either side of the bearings.
-Parallel cables internal and external $15
-Wire, other misc electrical components, Gunhead like ethernet
connection (looks like it), terminal blocks, zipstrips, crimp
connectors, LEDs, instrument plates, and switches, I will have to put
at $100 extra.
That's $515

For a grand total of $1195. And Gunhead only wants $200 more to make
every part and assemble the control box? I'm sold on the Gunhead.

I can not see how I can make it for cheaper. I could save a little if
I scrimp and bargain shop for some of the parts, but only like a $100
or so I assume. Plus, I would have to make everything, assemble it
all. I actually just want an easy build. I have my designs to make, I
don't want to have to build a lathe too.

BTW, I have a Tools Now 7x14.

Brian

[blades]

I suppose this kit is as close to turn-key as you can get without buying a lathe already converted. But like Mark mentioned, I'm not a very big fan of how excessively they've grown the footprint of what's supposed to be a "compact" lathe. Looks like you will also lose the chip guard with this setup.
CNCfusion also has a kit available (or at least in the advanced stages of development). CNC Fusion posted on here several months ago showing their prototype, and it looked pretty decent. Still no pricing or availability info on their website though.

[RotarySMP]

Hi Brian,

I removed an error I made in my early posting. I said the Aluminium block on the cross slide cut down the swing over the corss slide, but that was my not seeing in right in the main picture. Actually the way they have that block doing double duty as ballnut carrier standoff, and tool post riser is kind of cool.

Since you already have the 7x14 the advice to get a 10x or bigger is irrelevant.

I wanted to learn the CNC stuff, so I started with an NCStep stepper driver I had to solder together myself, unipolar motors, 32V PSU and amce screw.

Over time I have upgraded to Keling bipolar steppers, ballscrew, 50V PSU and Phytron ZMX drivers. Doing things twice meant the total cost was probably no saving over what you will pay. I just approached it from a different angle. Since you want to make parts, rather than muck around making a conversion, don't let us discourage you.

As noted, Gunheads seen to have chosen and matched the motion hardware well, so you should be happy with it, within the limitations of the 7x machine.

Please post photos of your installation of this kit. It will be interested to see your experience.

What software are you going to use?

I use TurboCNC. I would like to change to EMC2, but the laptop I use gave rather disappointing pulse train performance when I tried it. I don't have space for a desktop PC on the balcony. Turbocnc is mostly great, but the tool offset control sucks, as it is mixed in with the machine offsets.

I use a Phase II AXA tool post with a mix of about 20 Phase II and shars tool holders. This works great.

[doorknob]

I haven't seen much discussion here of the Gunhead CNC turnkey lathe or the various CNC retrofit kits that they offer.

It does appear that their current pricing is much greater than what was described in this post. Maybe they have upgraded their lathe conversion design and parts, or maybe they have just upgraded their prices.

I may have overlooked it, but I haven't found an actual address or phone number for that vendor on their web site, which is a bit of a turn-off.

By now, there must be enough people who have experience with the Gunhead kit as well as the CNCFusion kit to get a comparison, but I haven't seen one yet (not on this site, anyway). I'll keep looking, though.

I have a 7x10 (which I have considered retrofitting to a 7x14), and am considering getting a CNC upgrade kit, or doing my own DIY CNC upgrade, or possibly just getting a larger lathe and CNC'ing that (maybe a G0602, or maybe something larger like a 12x36). It may turn out that just going through the experience of upgrading the 7x10 will be worthwhile before I jump in to the deep end with a larger, more capable (but more expensive) CNC lathe project.

So, if anyone has any more recent info about this, I'd be interested in hearing it (or, if this is the wrong place for such a discussion, I guess that I could start my own thread)...

[doorknob]

OK, I guess that I'm answering part of my own question, but based on the "questions and answers about this item" in the eBay listing at Gunhead 7x CNC Mini Lathe KIT 7x10 7x12 - eBay (item 220659066134 end time Apr-20-11 13:04:06 PDT), this is apparently their "New Version 2 kit" (although they say in that listing that the photos are the Version 1 kit, which does not look like the Version 2 kit).

Also it notes that their CNC lathe is based on the Axeminster SC2 7x12 lathe (which is apparently a Sieg C2 lathe, perhaps with some changes, sold by a UK company Buy Axminster SIEG SC2 300mm Mini Lathe from Axminster, fast delivery for the UK).

They go on to say that, "Version 2 makes improvements over the original design. Both the hardware and electronics have changed. And the electronics run on 110V/60Hz AC (USA Standard)."

They state that their kit works on "All Seig 7x variants. From the 7x10 to the 7x14."

But they don't appear to clearly state where they are located (although under Shipping and Handling it says that the item location is Glenwood, Illinois, United States, and that UPS ground shipping is $50 to anywhere in the USA) Their web site has a mysterious "paintball" link, and their eBay feedback shows a number of gaming and paintball related items sold, and so my tentative conclusion is that the kit is being manufactured and marketed by a company that got its start manufacturing paintball accessories, and that they used mini lathes for their own internal production, developed an in-house CNC conversion for the mini lathe, and then decided to manufacture and market lathe upgrades. Presumably that's related to the moniker "gunhead". Cool...

And then they also state, "You get everything, but the lathe itself. Hardware mounts, leadscrew, mechanical components, assembled electronics control box, spindle speed control (a new addition to the kit), and instructions on how to install and setup. You may want to consider a Turnkey lathe instead. Out new lathes have 22" beds, a 4" chuck, brushless DC motor for the spindle(higher wattage than older models), and comes to your fully assembled. Goto Gunhead - Choose a Division for free shipping on turnkey lathes, for a limited time. ALSO ALL KITS AND TURNKEY LATHES WILL BE BASED ON GUNHEAD'S NEW VERSION 2 CNC COMPONENTS, NOT WHAT IS PICTURED HERE. Plenty of improvements over the version 1, and new features added (spindle speed control).".

So I'm not sure whether now they're also supplying kits and turnkey lathes based on the Sieg C6 or on the G0602 or on something else.

Continuing to do searching...

[sansbury]

IMHO if all you're doing is pen turning and the like, just buy a Sherline or Taig CNC lathe setup and be done with it. Price will be similar, and you'll have a class-A setup from a real machine tool builder for what it is. They are going to be better than the 7x until you start swinging larger stock where the iron on the 7x starts to help, maybe 1.5" and up, and much above that, the 7x becomes pretty flaky too.

I have a 7x which I later cnc'd and it's OK for what it is, but no way I'd spend $1400 for one. I built mine using the stock screws and parts in my scrap pile, so only cost was a couple hundred for the steppers and drivers.

My suggestions would be:

1. If your work is mostly 2" or less, get a Taig/Sherline.

2. If you do much "larger" stuff, buy at least an 8x12 (ideally, a 10x22). Even the 8x is a vastly better machine than the 7x, and doesn't cost that much more.

3. Use it manually before thinking about CNC-ing it, a manual lathe with a quick-change gearbox is pretty flexible, and a lot of people find CNC to be a much bigger PITA than they want to admit.

4. If you do buy a 7x, don't bother with fancy conversions, start by doing a conversion using the stock screws. If it's good enough, you saved yourself a lot of cash; if it's not, all you spent was some time. All the spendy parts can be used with ballscrews too. Either way, save all the manual parts, because if you ever want to sell it, the best way to sell it will be to convert it back to manual.

5. If you still insist on buying a 7x (I did, because I couldn't fit anything bigger in my basement), the only 7x I'd buy is the Micro-Mark 7x16 hi-torque model. I bought a 7x10, but it was on sale at HF and I had a coupon, so I paid like $275 for it. If I knew then what I know now, I'd have saved my nickels and gotten a longer one. The longer bed makes setups MUCH easier, especially anything involving the tailstock. You can't have too much length.