Hello all,
I am considering buying a machinist mill to do cuts in wood. I sell wooden marble runs on my website www.kingscubed.com and am considering doing them on a mill because I have a lot of waste due to being out of tolerances.
My question is, do you think that a machinist machine has enough torque to cut a groove with a 3/4 corebox (round nose) router bit on top of a soft maple cube in ONE pass, in a reasonable amount of time? (as compared to a router)
I have never done any work on a machinist mill and have no clue if this is reasonable or not. I know on a dill press, sliding work sideways under a bit is not only dumb, it won’t work.

The router bit I use is at http://www.amanatool.com/bits/45900.html
The machines I am considering, because they are in my price range are:

Grizzly http://www.grizzly.com/products/item.cfm?ItemNumber=G9959
And http://www.grizzly.com/products/item.cfm?itemnumber=G1006&

Shop Fox http://wttool.com/p/2007-0005


Thanks for any insight and sorry if this is a lame question.

Mike King
Kingscubed.com

cant say yes to the ? but i can say i have used one of the metal mills of theirs and done wood on it i have a metal lathe of theirs i do wood on also for the cost hold out a few and get one of the metal mills then you can work on either with the wood set up your kind of limited to what you can work with


p.s. i just looked at your site very cool stuff haven't seen those since i was a kid!!!!! i think you would have no probs doing that kinda stuff with their wood mill but like i said if ya hold out a few you could go the metal mill and work both wood and metal if needed

The spindle speed will probably be too slow. You want at least 10K rpm for routing wood.

My question is, do you think that a machinist machine has enough torque to cut a groove with a 3/4 corebox (round nose) router bit on top of a soft maple cube in ONE pass, in a reasonable amount of time? (as compared to a router)


Mike

I use my mill all the time to cut test pieces in wood before cutting
actual part into steel. (just a reg 9x42 bridgeport)
similar to the shop fox model you posted

I usaully use a 4 flute endmill/ballmill, crank up the RPMs

when you say 1 pass, how deep? 3/4", will cut like butter
will need sanding though


Dan

In answer to your question...yes you can cut wood on a 3 axis mill. Unfortunately you probably won't have the speed to make a full depth of cut in one pass and you'll need to do some sanding to get a good finish. Most mills were meant for shallow cuts. The bigget problem is the time it will take you...turning a hand crank all day on a mill can be very tiring. You can buy a drive motor for the table but that adds to the cost.
Having looked at your product I would look at a Multi-router made by JDS in SC. It's in the same price range and would certainly outlast the Grizzly mills in a production operation.
http://www.jdstools.com/index.asp?PageAction=Custom&ID=5
With a custom template and a fixture (or two) you could cut all you blocks without relocating the work piece. Using a depth stop you could adjust the final depth of cut and make a few light passes in just a few seconds. With some practice you could get a finish that required no sanding.
As usual, I have no interest in JDS just think it's a good product.
I like your product..pretty interesting.

seems to me that all you need are Jigs jigs jigs, and failing that, you could set up a cnc router and programs programs programs.

With the jigs, I would go for an overhead router, you would get your repeatability, and all you would have to do is pop the cubes in and out of the jigs and run them through the overhead router (run them through is an oversimplication, but it isn't a difficult process, just follow the path of the jug with the pin on the table).

Now, If you were to go the cnc route, and your cubes were well milled square and true, could you not arrange them to it the size of the table (whatever table size you chose) let the program run, it could cut down, across... and since the pieces are butted up against each other when you run out of the block you don't risk chipping out (the fibers are supported by the block next to it).

I second the opinion about the speed as well, i know the metal lathe i have used didn't reach the rpm's required to give me a proper clean cut, but that may be just the machine i was using. If you went the CNC rout you could in theory fiddle with the speed until you got a perfect cut almost every time, and probably much faster than you would with the mill.

Finally, and I may be shot down on this (or my other points for that matter) I don't think that the aquracy that a Mill will be made to (which accounts for the price of it) and able to attain, is more than is required for wood working. This is a material that will expand and contract significantly, throwing most tolerances to somewhere in the 1/32" range (and that is pretty damn good in my opinion, i have worked in cabinet shops where they claimed their tolerance was 1/8"-1/4") So for that price you should be able to buy a decent Little CNC machine that doesn't need to be the most accurate thing on the planet, but will do the job.

I hope i didn't get this completely wrong, but it looks to me as if you are trying to produce these things, and if so, you would want a machine that can dot hem fast, or do many of them at the same time.


please correct me anywhere i am wrong, (and i know there will be many corrections)


rock

Mathew

Thanks to all for the really great feedback! This forum rocks!

Tag1987:

Thanks for the tip on the Multi-router. I’m not sure how it works so I ordered a video on it. It looks very interesting.

Mcnotashark:

We currently do use jigs in our production. We keep things pretty close to tolerances but not close enough. The reason why accuracy is so important is because if you have cubes that are off, by the time you stack 6 of them high you create a lip. When the marble hits this lip it slows or even stops it completely. The tighter the tolerances, the smoother and faster the marble rolls. Woodworking equipment is just not made for that precision. True, the wood itself is a variable that does not lend well to accuracy either BUT.. With choosing very dense hardwood, controlling moisture content in the environment and lastly, “impregnating” the cube with a sealant has worked well to combat variances.
I would love to get a CNC router, but I can’t find one under 3k that would work.

One last question and I won’t bug you guys again 

I want to find out if the Multi-router will work first, but I’m leaning towards getting the grizzly G1007

http://www.grizzly.com/products/item.cfm?ItemNumber=G1007

It has a power feed so I can do what mcnotashark suggested by just lining up the cubes. Here is my question. If I make a custom pulley for this machine to gets speeds of around 10,000 RPM, would the bearings be able to take it? It’s a 2HP motor so it should have the torque.

Thanks again to all of the feedback I got.

I would invest in a thickness sander to machine the blocks to final size. Sand the board to thickness, then rip and crosscut and sand those to final size. You could make a "sled" that held 20 or 30 blocks at a time, wedged from the sides, and sand them all at the same time. Do you machine the holes and grooves on more than one block at a time? If you bought a CNC router, you could take the sled from the thickness sander with all the blocks held in place, and go to the router. Then you could machine all those blocks at the same time as well. That would also reduce the chipout as all the blocks would back each other up, and the frame around the blocks that held them in place would back up the outside blocks.

Rich

http://www.grizzly.com/products/item.cfm?ItemNumber=G9959&gid=2D199740-A4DB-45F4-8549-162ACA9C076F&site=grizzly

This is a wood mill that can work metal also and would seem like a good starting point with a 5000RPM spindle max. speed, about twice that of a standard metal lathe. I know little about CNC or wood but it would seem like what you are dealing with is cutter tooth speed and this is the quickest mill I know of.

Hu

Beware of what the saw-dust will do. I purchased a nice looking metal lathe a few years back. It was, at the time, a total steal. After carting it home and inspecting things closer I found that the whole machine needed to be disassembled, cleansed and reassembled. The first owner was turning a fiber type material for the oil industry. The saw-dust found its way in to every part of the machine. Several gears and bearing had to be replaced do to the damage. Oh well you live and learn. At least that's the way it is suppose to work.

Good luck
Brian

King,
I am not sure torque or rigidity would be your primary concern, but rather chipload and surface footage. I work on CNC routers and CNC metalworking machinery, in general CNC metal working machines are substantially more rigid than CNC routers. The drawback for you is acheiving sufficient RPM to get a quality finish in wood with the limited rpm window present on most metal working machines. The reason you take lighter depths of cuts in metal, is because, well, its metal.
I think this comes down to how economically you want to start out producing these,(( which are super neat, (I want a set for my kids!)) If you are unsure of your forecast, demand, etc...want to increase these at a substantial rate but are unsure if the application warrants purchasing a mid to lower end router, I would say you could purchase a CNC assist style mill (bridgeport, chevalier, etc) with a basic two axis CNC assist style control for a relatively economical price. Then the problem becomes rpm, this can be stepped up with aftermarket style "speeder" heads. I feel comfortable that with the quill fully retracted, and the speeder unit and bit in place, rigidity will never be an issue. The drawback is you will probably never achieve an rpm sufficient produce a surface finish that eliminates sanding. Whatever type of machine you choose, you will need jigs and or fixtures, I do not see where you would need that many of a different type, but rather many of the same type.
Do we get free toy sets for responding to this post? :)
I hopes this helps and congratulations on a very neat product!
MarkT

You could mount your router to the mill frame.