No roasting the newbie...

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Harlech

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Well, not on his first post anyways. :p

I am having a hard time trying to find a place to start, so I am thinking my final vision and work backwards from there. I am looking to pick up hobby machining because... reasons. I have a lot of them. Gunsmithing. Bladesmithing. Stuffsmithing. You get the idea.

I am wanting (needing?) recommendations for a knee mill that I can put a CNC conversion on. My brother has approached me with an interesting business opportunity that I think would go very well with a CNC set up. However, I want to keep the flexibility of a standard walk-up mill. So.... that's why I am looking at this route as opposed to a dedicated CNC VMC. I could look at a good used piece of equipment, but I know a good machine poorly maintained is just as bad a a bad quality machine that is well maintained.

I would also like recommendations for any CNC conversion kits. I have done some research and they are literally all over the place. I am leaning toward a turnkey(ish) solution to complete the frankenmill. I know part of the 'fun' is getting it all together and working, but at my stage in life and with my physical limitations that is more challenge than I am willing to undertake.

Any way, that's all for the moment.

That Harlech Guy
 
Welcome to the site . :welcome:
 
There are quite a few options for used CNC knee mills. Several of the Asian manufacturers offer CNC knee mills (Jet for one) and there are plenty of Bridgeport EZ Trak mills on the used market. This could save you a lot of work.

Ted
 
Hartech, to help us, do you or your brother have any machining background? CAD, welding turning, milling, building engines/machines? Taking a tech course? The reason I ask is that learning CNC and basic machining is a big task. I used to "hang out" with a very experienced machinist that went from manual with DRO to CNC and he tore his hair out for about 6 months.
Next is what are you thinking about making in the business? That will add requirements onto your selection of machines. Speed being one of the biggest requirements. Machining a small groove in stainless is far different from Delron or aluminum. Pretty much any decent size machine can be converted to CNC. Lots of posts here about that and a link to one conversion above.
In general you get the biggest heaviest machine in GOOD condition that you can find. Old cast iron machines will dampen vibration and allow you to take heavier cuts faster, important if you are trying to make some money. Pay very close attention to the spindle and the table. Spindle bearings can be very expensive. The table needs to be very flat or you will spend a lot of time on setups. In most cases fixing X-Y travel is not to bad. Plenty of articles on this forum.
If you find something, examine closely and ask questions here. Everybody will try to help out. Charles
 
I can relate and am sticking with a manual mill. The reason is that nothing I do is for more than one part, so there isn't any need for making duplicates/production runs. It's also because I like the spontaneity of being able to walk up to the machine and getting on with things, rather than sitting at the PC for hours coming up with a design, then making real sure that the tool paths don't crash, and finally having the machine make one of something. Anyway, if you have some production parts in mind, then yes, CNC is a good idea (if it makes sense money-wise, that is). Lastly is what you mentioned about dual use. Most CNC conversions that I've seen remove the handles, making them "CNC or nothing." If and when I ever go CNC, I, too, would want to keep the knobs.
 
Welcome aboard!

I would start with a CNC mill. That way most of the hard work and the expensive part is done.

As far as having a CNC/manual machine, I would not have it any other way if that was the only CNC in my shop. You really need both. There were a number of high quality machines imported from Taiwan, built by Topwell, that were fitted with Anilam controls and sold under at least 3 different badges. Webb, Eagle, and I think SuperMax. Most of these were 4V class (square ways and about 3500 lbs) machines with a 10x50 table, and a standard BP 2J2, VS clone head. Many had Ericson QC #30 taper spindles. All retained the manual capability on the X & Y, and some were a 2 axis machine and thus had a manual Z (quill). The 3 axis models had no easy way to manually operate the Z. Most have a Servo brand power feed on the knee.

I see these machines on Ebay and Craigslist every now and then. Normally in the <$4000 range.

The other machines that are manual/CNC were the BP Eazy Trac machines, but these were not directly manual as far as I know. More of a fly-by-wire system with the handwheels operating encoders that drive the servos in manual mode, so no tactile feedback.

EDIT: It has been pointed out to me by @talvare that the BP Easy Trac does in fact have the handles connected to the ball screws, so my statement above is incorrect.

Here is a picture of my Eagle. Started life as a 2 axis machine, and is now a 4 axis after some upgrades and modifications. Switching between full CNC and full manual is as simple as a mouse click and flip a lever. Can also be operated as a 2 axis CNC with manual quill. Really the best of all worlds. I'm still using the original Baldor DC servos.
1578853629783.png
 
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Thanks for the response, guys.

First off, I grew up in a small engine repair / bicycle repair / locksmith / gunsmith business. (I have NO idea how my great grandfather got into all of those, or why my grandfather wanted to buy it from him lol). I have a fair amount of experience in mechanics, technical drawing, and welding. I have a metric butt-ton of experience in computers and knife-making. As far as direct experience running the machines, none. Want me to gin up something in Fusion360, or read or generate a technical drawing, I am groovey with that.

As far as what we would be making... my brother has asked me to come up with a line of outdoor knives for him to market and sell. I no longer have the desire to spend hours in front of a forge or a belt grinder. Then I ran up on this. This would be the perfect way to do what we want to do.

Video on CNC knife maker

We would be in a different market segment and price point from him or John Grimsmo, but the concept would be the same. The cutting would be relatively simple, as you can see. Speed would be pretty far down the list of requirements, as I would be the one actually finishing the knives and the machine can't go faster than the silly slow human. Well... and not end up looking like Lucille Ball in that candy factory episode.

Hope this makes things a little clearer.
 
I have a Tormach 1100 S3 and a Bridgeport with a 2-axis Anilam controller. Between the two, I'm probably 90/10 using the Tormach vs. the Bridgeport because of the controller differences (2020 technology vs. 1981). As Jim Dawson mentioned above, super great to have a CNC/manual mill. I can manually mill with the Tormach using the jog shuttle or keyboard, but there's no "feel" as to how hard the machine/cutter is working. Go to the Bridgeport for every manual operation and simple CNC stuff.

There's a member on the forum here who is known for helping out with conversions if you want to upgrade an older Bridgeport machine to more modern controls. He even offers his control software for free. But sounds like you want a turnkey machine which makes sense if you don't have a lathe or manual mill to fab up what you might need for a conversion/upgrade and/or the fixturing for your knife-making.

John Grimsmo is a pretty well known knife-maker who uses a Tormach machine (maybe has others). Here's a link to his website:

grimsmoknives.com

Grimsmo Knives - Premium Pocket Knives and Precision Pens

Makers of high quality customized pocket knives and precision pens. We manufacture these products in our CNC machine shop located in Ontario, Canada, where we use the best materials on the planet to manufacture each component. With many patterns, colors, and finishes, the combinations are endless.
grimsmoknives.com grimsmoknives.com

Or hit YouTube and search for "Grimsmo knives" for some of his videos.

Bruce
 
Welcome to the CNC sub-forum. Lots of incredibly experienced and knowledgeable people here. Looking forward to seeing how this works out for you.
 
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