New X2 Mini Mill Base

[Harlow]

New base for the X2. Uses the Mini Mill X2 column and Spindle. Made with Polymer Concretes and Epoxies for structure. Our own Polymer / Delrin glides on fully supported aluminum rails.

Specs:
Swing Over - 8 5/8" with our 2" extender (included)
Travel / Cut Area – X = 26.5”, Y = 8.625”, Z = 9” (to the top of column)
Table Size – 12” x 30”
T-Slot Area – 10” x 24”
Table Slots – 4 raised casting areas to attach T-Slot surface type of your choice
Weight – 115lbs
Acme Screws – 5/8” x 8tpi x 1 start with dual ½” x 40mm x 12mm bearings
Backlash Nuts – 2” Delrin with Buna-N O-Rings for compression


Performance: Components used – 30v Power Supply, Applied Controllers @ 2.6a, 270oz.in. Steppers
X = 90 ipm
Y = 90 ipm
Z = 50 ipm (without offset weights or springs)

We have 8 of these available for end of October delivery.

Prices:
Base without aluminum T-Slot plates - $399.00
Z-Axis - $40.00 w/base
Z-Axis - $59.99 w/o base


Contact harlow@bellsouth.net for orders or shipping quotes. We will have a web site up shortly for taking orders and hopefully real-time shipping calculations.

web Site - CNCBridges.com

Thanks, DeWayne Harlow

[ataxy]

wow nice addon for this small mill

[Harlow]

Thanks ataxy. Working on Web Site now for ordering and more info. Should be up soon.

Harlow

[pminmo]

Nice, I wondered for some time about concretes and epoxies for usable machine structure.

[Harlow]

pmninmo. Usable would be an understatement. Better in my opinion. Epoxy itself cost as much or more than aluminum per cubic inch(.29 for Al & .26 for Ep) but when combined with concrete, steel re-inforcment and the proper techniques you actually get better vibration and resonance absorption than iron. Concrete and Polymer/Concrete actually weigh about the same as Aluminum ( 1cf Al = 176lbs, 1cf Polymer Concrete = 120-180lbs depending on the mix.).

All of our future products are based around these materials. They're cost effective and fun too work with. We have a large Bridge Gantry coming out soon using the same materials.

"Machines constructed from polymer concrete typically have six to ten times the damping characteristics over machines constructed from cast iron. Polymer concrete also has excellent mechanical and thermal characteristics."

Harlow

[harrisson]

Very nice DeWayne,

Wish I could afford,
I did a spindle kit for that head, see
www.harrisson.biz/beltkit.htm

any comments, suggestions proposal are wellcome

Sonny Harrisson

[Harlow]

Nice design and anodized aluminum. I'm building my site now and will link to it.

Harlow

[daedalus]

Do you cast this material in moulds, or machine it? Can you set parts into the resin, such as threaded inserts?

Are you just going to be producing X2 addons, or will you do custom parts?

[Harlow]

daedalus. All components are cast in molds. After the mold is made it's faster. Large parts are cast over several stages to accommodate set up and curing. Some parts are cast in multiple sections and assembled. Casting is done on +- .001/ft surfaces.

We do set parts into the resin. Where the column mounts to the base we have 3/8” stainless steel washers and bolts embedded to receive the bolts holding the column on. We also embed receiver nuts in the table T-Slot risers.

This X2 base is just the start. This has been a three-year startup. We currently have about 36 products designed and waiting. An enclosed cabinet and fluid tray for this Mini Mill are next.

Custom Parts? Custom parts could be expensive. What I would like to do is see what people want and go from there. Example: One thing I think would be a good product is a T-Slot base in standard sizes to go on gantries or be used on top of existing gantry beds. If you look at the pics above you can see the aluminum T-Slots are attached from above to the PoCre table. The same thing can be done with standard, flat sizes. 12” x 24”, 16” x 32”, etc. We have this worked out already so they can be attached together to form a large, ridged T-Slot base. Clients install whatever they want to the top and then mills flat.

thanks, Harlow

[daedalus]

Well from an end user perspective, if i was buying a new mill this would definately be an attractive option. Is there a reason you decided to keep the stock column, instead of casting a replacement?

Have you got any data as to the finish quality you can achieve in ali and steel with your new set up?

Also if you dont mind me asking about the process of casting these parts, what are the moulds made out of?

The reason i asked about custom parts is that i have been collecting bits for my mill, and already have thk rails and ground ballscrews, so i would want to use them in my build.

[Harlow]

daedalus. I kept the stock column for a couple of reason. 1st, because thousands of users already have it. 2nd, because a new column would have raised the price out of the market I wanted.

Cut quality is good. We put most of the mass / weight in the table to help eliminate chatter. More mass and weight = more resistance to sudden movement. I know it reduces the ability too make abrupt changes in direction so it might slow a job down by a few nanoseconds. I'd rather have the mass / weight. Funny thing about any type of material, whether it's metal, wood, concrete or polymers. They always seem to know what they are being hit with, how they are being hit and who's hitting them. Put a 10 lb piece of aluminum on a 10 pound table and it can fight back better than when on a 60 lb table. Say you hit a spammer square in the nose. Now take that same spammer and put a 40lb sack of sand on his head. With the sand, his head will resist moving back to the blow so you can inflict more damage. During testing we purposely overloaded cuts to get chatter and felt the machine to see where the vibrations were. Just from touch I would say 90% were in the head and column. Often you can feel them in the head / column and not at all in the base.

Our molds are made from different materials depending on the application and part being made.

Originally we were going to use our new bearings on this but I wanted a lot of rigidity and resistance to the cutting force. It seems to me, if you use bearings and ballscrews then the only thing holding a material back from the cutting forces is the mechanical connection to the motor and the material / table weight. This unit is doing 90ipm with 30v, 2.6a and 276 oz.in. I am more than satisfied with that. With Geckos and 60v it should see 140ipm. Add 640s to the Geckos, change to 5tpi ACMEs and I can see it doing at least 200 or more. I am not taking the time for the math right now. Just guessing. If you want a base, table and column for your THKs, contact me through the web site with specs. If we come up with a standard that others can use then it’s doable at a good price. The site will be up shortly and posted here.

Thanks, Harlow

[ZipSnipe]

Nice job Harlow, I,ve used the mini mill head in my design and am in a ongoing process off eliminating chatter and vibration. May I suggest putting or designing a beefier side plates for the head and maybe for the column going up to the head. I did on mine and made a world of difference. I am currently redesigning the head assembly to eliminate even more chatter. I,ve seen the mini mill in person and while it is good for someone doing small plastic models and very light metal work it won,t give you the beef that many would probably wether have. So it,s nice to see you have come up with interesting add ons. Keep up the good work.