How to make best use of your milling machine. Tips and techniques

[gjdale]

Nice to see your adaptation on this one Jay. I would be a little concerned about using climb cutting for this though, because of the danger of the cutting bit "grabbing" the stock and pulling it through.

 

I agree with you on your thoughts for a hold-down featherboard (or two) of some description. I have the kernel of an idea wafting through my head at the moment. As soon as I get a bit of time, I'll have a crack at this one too.

[Mahuna]

Hi Jay:

 

The 6-32 socket head cap screws that hold the guide are screwed into 6-32 t-nuts that are inset under the table.  These t-nuts have small spikes which keep the nuts from turning and the narrow collar is threaded - in this case for 6-32 screws.  Here's what the t-nuts look like:

 

 

These t-nuts are inserted through the bottom of the table.  I first use a 5/32 bit to make the hole through which the narrow collar will sit.  Then I use a 5/16 spade bit to make the larger hole, and drill this deep enough to bring the narrow collar almost to the top of the table.  Here's a view of the bottom of the table with t-nuts installed for the guide and for holding the fence.

 

 

Hope this helps.

[Modeler12]

Yes, Frank, I am familiar with these nuts and have used them in the past (although the ones I have are 1/4-20).

 

Meanwhile I have added a couple ball bearings on the fence. Using the same piece of wood as before (1/8 x 5/32 basswood), I routed it and it was very easy to push through with no chatter or up and down variations.

There is a small nut on the back side of each bearing to hold it in the slot. I am limited to about 3/8 inch vertical but for any wood that thick, I don't think I have worry about using the hold down feature.

In the picture you can also see the slot in the table as well as in the metal guide. That way I can move the whole thing back and forth about 3/4 inch. It goes to show that there are different ways of doing things like that.

Edited September 12, 2015 by Modeler12

[mtaylor]

Nice to see your adaptation on this one Jay. I would be a little concerned about using climb cutting for this though, because of the danger of the cutting bit "grabbing" the stock and pulling it through.

 

I agree with you on your thoughts for a hold-down featherboard (or two) of some description. I have the kernel of an idea wafting through my head at the moment. As soon as I get a bit of time, I'll have a crack at this one too.

 

I did a very crude version done quick and dirty using scrap wood of this milling table for some trim strips... I'll be making a better one.  On the climb cutting, a featherboard or as Jay did with the bearings might be enough of a brake to keep that happening.  On my crude version, I just used a piece of scrap wood in my hand to act as the brake.  Didn't work great but it worked for wanted it for. 

[Modeler12]

I like this router table. A bit of experimenting with cutters yielded this one.

A 1/8 inch center drill has the tip diameter of 1/16 inch almost round.

I used it on a piece of 5/32 inch boxwood and cut two grooves right next to each other.
The calipers in the picture is set at .062 inches, the width of the grooves.

  

This could be used to make decorative fluted columns, for example. I would need to include two stops.

 

 

[Mahuna]

Hi Grant

 

A friend pointed me to your post on making a mortar for your bomb vessel - great job.  You're obviously getting very proficient with your mill and lathe.

[gjdale]

Thanks Frank. I still consider myself very much a novice at this, but one who is willing to have a go and learn along the way. Picking up tips from people such as yourself helps to understand the capabilities of the machines and how to use them. Then it's just a case of putting them into practice - that s the easy part!

[Modeler12]

I have always wondered about making my own milling bits to the shape I want. This is my first attempt to do that.

 

I took an old 1/4 inch router bit, mounted it in my rotary table and used the old 'Monkey-Ward's' (Dremmel like) motor with a grinding stone (cut-off wheel or shaped disk). Safety glasses!!

I then moved the mill to the area on the bit that I wanted to remove. Here I get confused all the time because of the 'image' problem.
Meaning that what you remove is not what the final routed shape looks like. How do I describe this?

I had to do this on both sides of the bit by turning the rotary table 180 degrees. I also had to be careful of the angle the grinding wheel makes with the leading edge of the bit (clearance for the cutting edge).

 

 

My first tries were very gentle and nothing too exciting, but I proved to myself that this works. It is safe as long as I take small bites for the grinding process. Note this is not like holding the dremmel tool with bit to do this by hand. I never liked that idea.

 

I have made scrapers out of saw blades, but even then mounted the old piece in the lathe toolpost and the grinder in the chuck.

 

I tried the minute grooved router bit on a piece of boxwood and the results are below. 

Now I am ready to try a much larger shape.

BTW Don't try this on a bit that has a carbide insert. All it does is grind the grinder!

[Mahuna]

Great idea Jay.  I'm not sure of the setup you used - "..used the old 'Monkey-Ward's' (Dremmel like) motor.."  Was this off the mill or somehow mounted on the mill?  I would have thought the bits could be used right on the mill using a drill chuck or a collet.

[Modeler12]

Frank, I should have explained that some time ago I added a clamping fixture to the side of my mill to hold the dremmel like tool. Perhaps the picture below makes that clear. The mill has two ways to move the z axis. There is a long screw in the back that raises the whole head up or down while the blue section can be moved with the quill and knob shown in front. I can also use the lever barely shown to the far right.

The quill has two worm gears. One attaches the 'drill press lever' to the quill to move it up and down by hand. The second one activates the calibrated knob in front. There is a button (barely visible on the black tapered part) that engages this worm gear for fine z tuning. 

 

The four jaw chuck you see is still mounted on the mill bed (via the tilting and rotary tables). So the router bit is mounted on the mill bed and the Monkeyward's tool does the grinding.

  

Edited September 16, 2015 by Modeler12

[mtaylor]

I thought I'd put this here, if you think it doesn't belong, Jay, I'll delete it.

 

I have a 3" rotary table... and finding a chuck was a bit of a challenge as far as size.. including height.  But I found this one:  http://www.amazon.com/gp/product/B005W11SQ2?psc=1&redirect=true&ref_=od_aui_detailpages00   Weird but the price varies by a few dollars whenever I go there... hmm...  They also list a 3-jaw and a 4-jaw self-centering chuck in the same size.

 

 

It's a bit stiff as there's some burring that needs a touch or two with a file.  The 4 jaws are independent and they provide an extra set of jaws (to hold closer to the table) and they are reversible.  Also included are 4 nuts and bolts for mounting to the rotary table.  Quality seems comparable with some of "better" stuff coming out of China.

 

Anyway, just wanted to share in case someone else had a small rotary and needed a small chuck.

[Modeler12]

About ten days ago I ordered a set of six bits from Ebay. The price was under $3 plus around a dollar for shipping. I used Paypall to pay.

Yesterday I received them in the mail from China. They were made in a small town about 150 miles southwest of Shanghai.

I tried a couple on my mill and the results are shown below. 

They all have a 1/8 inch diameter shaft. I ran them at about 5000 rpm but for the smaller sizes it might have been better to use a higher speed. Notice one is actually a dove tail.

At any rate, for less than $4 for six bits I cannot complain and I may order a few more of different shapes.

[wefalck]

…. Meanwhile I have added a couple ball bearings on the fence. Using the same piece of wood as before (1/8 x 5/32 basswood), I routed it and it was very easy to push through with no chatter or up and down variations.

There is a small nut on the back side of each bearing to hold it in the slot. I am limited to about 3/8 inch vertical but for any wood that thick, I don't think I have worry about using the hold down feature...

 

I like this idea of using small ball-bearings as hold-downs and may adapt it to one of my machines 

[donrobinson]

 I just realized I have posted this on the wrong topic, please move if necessary. This planking jig was made using my Sherline mill and lathe(my first attempt on a real project), it is a copy of someone else's here that was made of wood(I apologize for not knowing your name).

 I used 1/4" aluminum for all the sliding parts and some 1/2" round stock for the thumb screws.

 I avoided using a ball bearing on the end, as was on the original, as I was worried about thin stock sliding underneath it. The only flaw is that I am limited to approx. 13mm(1/2") in width, which should not be much of a problem. When in use the stock slides by with no binding and appears to be quite accurate in maintaining a consistent width throughout the entire length.

 It is a bit of a pain adjusting fence for every plank but for the sake of safety a little more time taken is well worth the effort.

 The original one was used on a Byrne's saw, I believe, and he used a spreading system to lock his in place, I have a Proxxon which has a "T" slot making for a little different locking system as you can see.

 There are no patents on this so feel free to copy(lol), if you want any measurements or more info feel free to ask.

 Again I apologize for posting in wrong forum.

 

[rtropp]

Don,

Very nice.

 

Which grade of aluminum did you use?  The grade I tried seems too tough to mill in my micromill.

 

Thanks,

Richard

[donrobinson]

Richard,

Thanks

 

 I am not sure of the grade, next time I am out in the shop I will check to see if there is any kind of grading on it. I bought it at a local hardware store, so I am sure it is nothing special. I had no problem milling it, although, I will say my end mill bit was brand new which I am sure helped also. Cutting it to length with a hacksaw was no problem either so I am thinking it is not that hard of a grade.

 I am new to this and do not know my metals that well, but I will check for you.

 

Have a Good Day

[Mahuna]

onlinemetals.com has a good description of each type of aluminum, brass, and ferrous metals.  These descriptions indicate the types that are best for machining.  When you buy aluminum from a local store it often will be stamped with the type, and you can tell from this whether it will machine easily.

[Modeler12]

As the web site Frank mentioned, the most common alloy is 6061 and I am willing to bet that is what you used.

All the others would have be bought from a special metals shop.

When employed, I worked a lot with other alloys in the aircraft industry. 2024 for example was used a lot on the F-14 (Navy fighter) because it is also corrosion resistant compared with the others. 5052 was used a lot on skin panels, honeycomb and other structural parts. But again they are not your common Home Depot variety.

[donrobinson]

Not sure if this helps as far as the grade goes it does, however, show that I was wrong when I said it was 1/4" thick.

[rtropp]

Thanks all,

the online site suggested by Frank was very helpful.

 

Given the sites descriptions, the difficulty I had with 6061 must have been my inexperience, the cutters or equipment, or perhaps my impatience with how slow it went.

 

I will keep trying.

 

Thanks

Richard

[Modeler12]

I mentioned that I had installed a rotary and tilting table on my mill. However, other than a trial run, I did not have any specific applications for their use until now.

Here is one that I just came across: Making and installing stairs.

 

In my cross section of the USS Constitution I encountered several stairs to go to the various decks. I am making all of them the same way, size and shape. (More about the 'making' later). However, the location will dictate their angle of installation.

And it is this angle that led me to a situation where the raised part of the orlop deck needed to be cut at the stair angle. I clamped the 'hold deck' part in the four jaw chuck and rotated the table to the 65 degrees I needed. The pictures below explain the rest.

Oh, in order to clamp this piece, I did remove two joists. but they were still loose and will be reinstalled later.

 

[Capt.Bob]

To all:

Just destroyed my budget and bought myself a MicroMark milling machine.  The mass destruction came from accessories.  A rotary table had me really confused about applications.  I held off to wait for fiscal recovery and to investigate worthwhile applications.  The bank will undoubtedly be sending me a Christmas card with the appreciation of their stockholders.  Also, any other accessories that people have found useful.

 

Bob

[mtaylor]

Bob,

Other than the rotary table, what accessories did you order?   Kind of hard to add to the list if we don't know.

 

I can relate to the Christmas card from the bank... I get one from the credit card company.

[peewee]

The micromark looks like the Seig that i have my eyes on from ArcEuro here in the UK, nice machine

[Q A's Revenge]

Nice high top speed (5000 rpm) on this one.

 

http://www.arceurotrade.co.uk/Catalogue/Machines-Accessories/Milling-Machines/SIEG-Super-X1LP-Mill/SIEG-Super-X1LP-Mill

[Capt.Bob]

Hi Mark,

Well, lets see:

1. (84634) 6 piece HSS end mill set 3/8 Inch Shank, Center cut, 4 flute

2. (82678) 3 piece Fly Cutter Set

3. (84700) ER 25 Collet Set

4. (83952) Power Feed Control Box

5. (82578) 42 Piece Clamping Set

6. (83383) Two-Way Milling Machine Vise

Total =$599.20

 

Bob

[Mahuna]

Bob:

 

If you haven't added the following yet, I'd recommend:

Parallel Bars

Edge and Center Finders

Dial Indicator

Calipers that will read to .001"

A set of machinist's squares

 

A good source for accessories is Little Machine Shop (LittleMachineShop.com).  Their prices are better than MicroMark, and they have a wider selection of products.  They also sell some good introductory videos.

[Q A's Revenge]

I also bought the three piece fly cutter set. Waste of money as I only ever use the largest one I've got!

 

I couldn't afford a clamping set when I first got my mill which is just as well because I made/bought individual clamping elements as I needed them. It's worked out far cheaper.

 

Safety specs - prescription ones are good if you need them.

 

1-2-3 blocks are very handy

 

11/2" square to get into tight spaces setting stuff up on the mill.

 

1" paint brush painted bright red so you don't loose it - great for cleaning chips off the mill vice/table.

 

Make a stop for your milling vice. Handy for repeat placement of parts.

 

Long neck LED light with magnetic base.

[captain.jerry]

I just wanted to add a few comments regarding milling aluminum.   Aluminum is a relatively soft metal and that is often the problem.  The harder grades actually are easier to mill.  If you order 6061 from any of the on line sources you should have no problem as long as your cutter is sharp.  The typical angles and flats that you get at the hardware may not meet that grade.  It is generally softer and "gummy" which is the problem.  The soft chips may stick to the cutting edge causing the cutter to become clogged.  That can be reduced by using some kind of lubricant to prevent the build up.  By fiddling with speed and feed rate you can produce better results. Sometimes, slower is better.  Most of the micro or mini mills have electronic variable speed.  A continuous stream of air can also help keep the swarf from clogging the cut.

 

Slots can be a particularly sticky problem.  If the edges of the slot are critical, as in a slide, I usually cut it in three passes using an end mill that is narrower that the finished slot dimension.  The first pass is down the middle of the slot, which leaves a small amount on either side.  This small amount means that the final cut is taking a much shallower depth of cut and gives a better finish.  If you must make a slot with a single pass, use a 2 flute end mill.  It has much deeper flutes that help clear the swarf.

 

Don't waste time or money trying to mill aluminum with an abrasive wheel or coated point.  You won't like the results.

[mtaylor]

The micromark looks like the Seig that i have my eyes on from ArcEuro here in the UK, nice machine

 

Indeed, it is.  Many of the mills that look like that along with many of the mini-lathes come come out of Central Machinery in China.  

 

BTW, here's a good link that has a lot of info:  http://www.littlemachineshop.com/default.php

 

Hi Mark,

Well, lets see:

1. (84634) 6 piece HSS end mill set 3/8 Inch Shank, Center cut, 4 flute

2. (82678) 3 piece Fly Cutter Set

3. (84700) ER 25 Collet Set

4. (83952) Power Feed Control Box

5. (82578) 42 Piece Clamping Set

6. (83383) Two-Way Milling Machine Vise

Total =$599.20

 

Bob

 

Bob,

What Frank suggested.   Having said that, I wouldn't buy things until you think you need them.  I have, for example, an edge finder that I've used once.  Then again, I'm newbie and may not be fully able to utilize it.