Member postings for Huub

I had the same problem on both my lathes.

On my small lathe is was only visible when moving the top slide. The cause was to much play in the gibs combined with a dry nut/feed screw. After cleaning and oiling the feed screw and nut and adjusting the gibs, the problem was gone.

On my bigger lathe, the problem was only visible when moving the carriage (power feed). It was caused by not enough / no play between the rack and pinion that moves the carriage. The problem was gone after removing the rack. Cleaning the rack, scraping some paint of the bed and removing some high spots (light sanding), under the rack, solved the problem.

I have a HBM BF290 300kg / 600 pound bench lathe. I disassembled the lathe completely and brought it upstairs part by part. The bed, without any parts (70 kg /140 pound) is the heaviest.

Disassembly took about a day. I bagged all bolts/washers/screws and taped the bag to the part. Making some pictures may help.
Assembly took about a week. Because it is a Chinese lathe, i used the opportunity to service the lathe.

I followed the same procedure for my mill.

If you have 0.1 mm misalignment over 300 mm, than using a 30 mm end mill would create 0.01 mm deep grooves.

My BF16 has a head that can be set in an angle. I have to loosen 2 bolts and tram the head (X-axis) by a set screw.

I to start using the angle grinder to roughly grind the shape in HSS. Then use the bench grinder (white HSS stone) for a better shape. Finally I use a small 80 mm diamond disk (€10,--) and jigs to grind and regrind the tools.

Drills, mills, slitting disks, roughing mills, rotary broaches and some form tools are ground on the CNC lathe.

I can regrind a HSS tool faster than replacing an insert. Nevertheless, most of the time I use carbide because they last longer than HSS tools. Sometimes HSS does a better job and small internal HSS threading tools cheap to make.

My HSS grinder (finish grinder) and some stackable holders.

If you are going to switch low voltages and want a long term reliable switch, than you should select a low voltage switch, not a 240V switch.

I think this is a better choice than building one without the proper tools and knowledge. When you have done the first one, you have the tools (milling machine) and more knowledge to build one from scratch.

For starting, as a learning project, any half decent milling (small) machine will do. The parts of industrial machines are very heavy and hard to handle.

On a hobby machine, you can't utilise carbide cutters to the max. For that you need more power, more speed and more rigidity but you can still benefit from carbide.

For me, HSS is not out of the picture. For coarse threading, when I reach the limits of my lathe, I use a HSS threading tool because HSS tools don't break/chip that fast. My form tools are made from HSS because HSS is easy to grind and HSS dust is not so harmful.

Edited By Huub on 09/02/2023 22:37:43

Jason,

I have got 2 types very decent AP?T inserts from a friend last year having a 0.8 mm nose radius. I was forgotten that I already bought a 12 mm holder for these inserts, found it in a drawer searching for the inserts. The next time I have to face some steel, I will test these 3 inserts under the same conditions. If it doesn't get any better, I will make some 12 mm boring bar holders for my DCMT070204, CCMT060204/8 and CCGT060204 inserts.

Buna Ziua,

Your setup is not rigid enough for milling steel. But if you use a smaller end mill the cutting forces will be less. This will give better results. Take your time because smaller end mills are brittal.

For a 3 mm HSS end mill in mild steel you can run 3400 RPM. Make sure you make (thin) chips. If you make "dust" you are feeding to slow and this will quickly dull your end mill. If you feed to fast, you make thicker chips but also risk breaking the end mill.

There is no need to start learning milling using expensive end mills. When you no longer break end mills, it is time to move up to a better and more expensive end mill.

I use a lathe internal boring bar (12 mm DCMT inserts) for milling steel and aluminium in my hobby mill. I also made a holder for worn lathe CCMT inserts (4 cutting edges) that uses the 2 in the lathe unused cutting edges. Both work great for facing and "milling".
My 10 mm milling tool for APMT inserts is terrible. I am not sure if it is the lack of mill rigidity, the quality of the cheap inserts or the large nose radius.

I have made a drilling spindle for the tool post using 6009ZZ plain bearings, an ER11 collet holder and a 170W BLDC motor.

I also made a milling spindle using AC7000 contact angle bearings, an ER11 collet holder and a 175 Watt Dremel.

For grinding, I prefer the Dremel milling spindle because it can run high RPM and the spindle is free of play. The spindle has a 3D printed adapter. I also made an adapter for a DC motor from an old cordless drill.

You can 3D print these gears, especially the large ones. You probably have to bore or ream the hole for the shaft.

It is the metal to metal contact that makes the noise. If you place a plastic gear between 2 metal gears, the gears run really quietly.

For this kind of work, I use sharp insert for turning aluminium (CCGT060204).

I make thick (2 mm +) shims by parting of a faced piece of stock. The back of the shim is than pressed against an adjustable stop and that side is faced. After that the front of the shim is faced to get the right thickness. Differences in thickness are less than 0.02 mm. If I face the adjustable stop, I can get differences in thickness less than 0.01 mm.

For thin shims, I glue the shim (superglue) on a faced arbour and face the back. The faced arbour is the reference point for the thickness of the shim. The shim is released (heated) and the shim and arbour are cleaned (acetone) Then the front is done the same way and faced to get the right thickness. Differences in thickness are less than 0.02 mm

An alternative would be using a magnetic holder (upside down) to clamp the shim and mill or grind the shim.

I have made a lot of tapers but never for the tail stock. Maybe this is a good way to get a better and more accurate tail stock. When I mess up, I can still use the old tail stock.

To assure parallelism and centre height and I would put the drill in the chuck to "roughly" step bore the taper using different drill sizes and feed by using the tail stock. If you don't have the right drills, you could use a boring head. Then use the reamer to finish the job.

Lathes are not direct driven because they have a spindle bore to turn long bars.

Some lathes have a Norton gearbox for easy gear (speed) change. They always run at max RPM and are loud and have a lot of torque in low gear. Others have a single pulley and a variable speed control. These are really "quit" but have very low torque at low RPM. Some lathes have a pulley and a 2 position gearbox. They ar not so quit and have a bit (2 times) more torque in low gear.

Some lathes have brushed motors and are loud but I also have a 1.5 kW brushed DC motor that makes less noise than my 600W brushless DC motor (BLDC). A timing belt pulley (teeth) makes more noise than a V-pulley. Metal gears make more noise than plastic gears. I made metal gears for my mini lathe but replaced them after a short period of use becasue the where to noisy.

Most of the time I have plenty of torque on both my lathes. Sometimes when turning 70 mm stainless steel or 180mm aluminium, i would like to have more torque. Also threading larger diameters 20+ mm requires a lot of torque. Then my lathes are not optimal but the job can be done. It just takes more time and hassle.

What you really needs depends on what you want to make. What ever lathe you have, it has its limits and some times you wish you had a smaller or larger lathe.

I don't expect your first lathe will be your last lathe. Once you have learned to use it, you probably will change your demands.

I agree, it is an unbalanced double action pneumatic actuator.

Stuart,
That looks like a pretty good PCB.
I want to build a PCB router because the build is also a tryout for the steel milling router that I am going to build. It also gives me the option to optimise the outside dimensions.

Peter,
Aligning a router starts by using the adjustment options (play) in the construction. After that, milling the table is a good option to get things right. If you use a (wooden) spoil board, you can also just mill the top of the spoil board.

Huub

Edited By Huub on 18/01/2023 12:02:13

Edited By Huub on 18/01/2023 12:02:37

I am going to use the method shown in this video. It uses Eagle and Flatcam.

PCB milling using Eagle and Flatcam

I use the Eagle (free version) for 10+ years and make my PCB's using the toner transfer method. I can't/want wait until a PCB arrives from China and I really like making my own stuff.

Extending the library in Eagle is "easy" if you know how to do it. I expect this applies to all schematic packages. For eagle there are also a lot of public libraries.

I have tried Kikad because it is open source but it couldn't get along with it, so I stick with Eagle. I am sure, that if I spend more time learning Kikad it will do the job.

I am going to build a dedicated router to make my PCB's. If PCB milling is your goal, you should select a package (probably a combination of packages) that can do this. Check youtube to find out how complicated it is before deciding what to use and take the time to learn it because, like all CAD/CAM software it takes some effort to learn.

I also use the method of Ivan Law to make bevel gears and these gears are OK. 3D printed bevel gears also do a nice job and are easy to make.