Member postings for Huub

I have a vice and rotary table from Soba. The best part is the wooden box to store the rotary table.

I must say, that after milling the vice square and adding a stepper to the rotary table, both are still in use for more than 10 years. Considering the price, I got the quality I paid for AND that quality is usable for low demanding hobby use.

My second vice, more expensive but not a brand, also needs some milling to get it square.
I made made my second rotary table (ER32 collet) my self and that is more accurate.

I use CCMT/CCGT inserts more than 10 years. I use the 2 unused cutting edges of the CCMT/CCGT on my mill for facing jobs.

The CCxT inserts are smaller than the TCxT inserts. That can be a benefit for small diameter internal turning. Due to the 5° cutting edge, on the CCxT inserts, swarf can build up easily and can get between the cutting edge and the part. This results in scratches on the just turned part and dimensions are off. In general, I prefer a TCxT or DCxT insert.
I make the insert holders my self so I can choose the cutting edge angle. I use the TCxT inserts at an angle of 15° for facing and turning.
For the DCxT inserts, you can buy Q type holders (SDQCR07).

In general,

• The head stock is misaligned
• The bed is twisted
• The bed is mounten on a surface that is not flat
• The bed is a bit worn

All these faults combined, results in deviations that are not on a straight line.

You can measure the misalignment at 200 mm from the chuck, but in practice, when you turn that length, the shaft will be supported at the end by a live centre. That will influence all results.

For me, the main question would be what error do I need (not want) to reduce.
I only measure misalignment over a length of 100 from the chuck.
You should also measure on top of the bar to see if there is also a vertical misalignment.

I have made a lot of collet chucks. The run out of the chuck (RC) is always far below 0.01 mm (0.0005". That is not a surprise because the collet taper is turned using the same lathe the chuck is used on. I measure this run out on the inside of the chuck!

The next to measure is the run out of a bar clamped in the chuck using a collet close to the chuck (RB). The RB run out is most of the time larger than RC but below 0.02 mm (0.001" because my collets are not that precise.

The last thing I measure is the run out at the end of the bar (RE). Generally, this is larger than the RB. It depends on the alignment of the head stock (HA) and the quality of the collet. On my lathe(s), the HA is about 0.015 mm/ 100 mm.

The thing to consider is how run out effects the result. If I can turn the part in one fixation, than it is of "no influence". If I have to reposition the part, and dimensions are critical, I use a 4 jaw chuck.

If I have to turn a long straight shaft, I use a live centre. I turn long shafts CNC and can easily correct for mis alignment of the head/tail stock.

If I need to turn a part between centres, I place a bar of mild steel in the chuck and turn a 60° tip on the end of the bar. Than the run out of the chuck does not matter. I correct any head/tail stock misalignment by turning the bar CNC.

Edited By Huub on 14/09/2023 21:59:41

The srew is Torx, T8, M2.5.

If you search for CCMT060204 dimensions, you find drawings of the insert. For the bolts you can search for Torx M2.5 insert screw

Look at the bottom of this page: CCxT0602xx dimensions

Edited By Huub on 01/09/2023 22:15:03

I find the PDF copy of the "Machinery's handbook" the best handbook I have because it is easy to find relevant stuff and it has a lot of information.

My German handbook "Tabellen Buch Metall" lists almost only metric stuff. Until now, it has never come with an answer and it is really difficult to find any information.

It seems that information differs, depending on the handbook I use. Also Internet information is not always consistent. So I check several sources to be sure.

The board is manufactured in China.

I have bought 2 boards from the MKS official seller. The delivery time to the Netherlands was within 10 days, both times. Select the version with the TMC2209 drivers without display.

The stepper and limit switches are connected using a 2.54 mm JST-XH connector but a 4 pin Dupont connector (breadboard pin) will also fit.

TinyBee store

TinyBee git hub page

Congratulations whith you new milling machine. I hope it will bring you a lot of fun.

I use grbl on my lathes (Arduino Uno and Arduino Mega board) and FluidNC (MKS TinyBee ESP32board) on my mill. It works flawlessly.

On the mill I use UGS to stream the Gcodes to the controller.

For CAD/CAM for the mill and 3D printer I use (freeware) FreeCad. It takes a lot of evenings to get familiar with but that is no difference than other CAD/CAM systems like Fusion360.

For the milling machine there is also EstleCam software. This is not freeware but relatively cheap (70$) and you don't need CAD/CAM.

I have 4 Dasqua outside micrometers from 0..25 to 75..100 (From HBM Netherlands). These are absolutely not the quality of Mitutoyo but more than accurate enough for hobby use. I would buy them again without hesitating.

I also bought 4 Dasqua inside micrometers from 5..30 to 75..100 (From HBM Netherlands). I have returned the set because it looked like they where (mis)used/tested/unboxed and 3 of 4 micrometers didn't turn smoothly.

I use the this PDF/handbook for o-ring & groove dimensions

Parker O-ring dimensions

Screw threads are normally not made at their nominal diameter but bolts a bit smaller and nuts a bit larger. The depth of thread is always the same. Doing this results in play between nut and bolt and that is needed for normal operation.
The play between nut and bolt depends on the thread tolerances. Normal hardware store metric nuts and bolts have a diameter about Nominal diameter minus 10% of nominal thread depth. Nominal thread depth equals the thread pitch.

I make my taps (command and roll taps) at the nominal thread diameter. I use the same thread depth as when threading a normal bolt using that tool/insert. That works fine for me when tapping aluminium (normal taps) or wood (roll taps).

My lathe tail stock has a little bit of play in the quill. I use this play to adjust the last 0.01 mm alignment by locking the quill a bit more or less.

The head stock isn't aligned perfectly. I can let the part stick out a bit more resulting a bit more bending during turning. That compensates for the misalignment when the tail stock is not used.

The chuck of the mini lathe has some run out. That is not a problem as long I don't have to remove the part.

The cross slide and carriage lead screws have some play. As long as I move them in one direction, it doesn't matter. For CNC turning I use backlash compensation and the movements are the same as I would do when manual turning.

A worn bed is not a real problem for short parts. When turning long shafts, emery paper can reduce the turned "tapers" to 0.

I have a HBM BF290 lathe that looks the same. I have made a QCTP that has a centre height of 12.54 mm and it can hold 21 mm tools.
I make most of my tools my self but have bought some (insert) tools that have a 16 mm centre height. I use the mill to make the centre height of the tools fit the tool post. I glue shims on tools that are to low.

This lathe is a bench top lathe and it is not that rigid. A 8 mm tool, with little stick out, is rigid enough to take a 0.5 mm depth cut in steel.
Any tool will do as long as it fits the tool post and you can get it on centre height.

I have tried a lot of stuff on my lathes.

On my mini lathe I use some old (new once are to stiff) jeans cloth bolted to the carriage and magnets on the head stock.

On my bigger lathe I have a piece of wood under the chuck mounted to the carriage using magnets. The cross slide is also covered by jeans bolted to the cross slide on one side and magnets on the other side.

Well done and a good anodising result.

Using a roll tap M3.5 x 1 for steel requires a drilled hole of 3 mm.

Making/turning a tap isn't that difficult but takes some time. This video shows how I make a tap from round steel Turning a tap. It is easier if you use hex steel.
For a roll tap, I use the same procedure but without milling the flutes. For wood, I use mild steel without hardening.

For wood, I use (and make) roll taps. That works better than my taps for steel.

Just make a M3.5 x 1 thread on a peace of hex steel and use that to tap the hole in wood.

Drill diameter should be the same as for a M3.5 x1 metal tap 2.53 mm (2.5)

Crest diameter for the tap should be 3.5 mm

Cutting depth for a sharp, self grind threading tool should be 0.704 mm

Cutting depth for an insert 60°, for 0.5 mm pitch should be 0.65

Edited By Huub on 13/07/2023 23:12:15

I to make my parallels out of mild flat steel. I marked the right side so they will be used in the same orientation as when made. This way I compensate for my not perfectly flat vice (0.04 mm/ 100 mm).

You can use these kind of "boring head / Fly cutter". I set the cutting diameter by using the drilled hole as reference, backing off the mill the amount requested, loosing the locknut, pushing the bit against the edge of the drilled hole and locking the fly cutter.

Fly cutter

0.04 mm is quit a lot.

If you want to measure the spindle play, you have to avoid measuring the flex/bending in the mill. You should place the (magnetic) base of the indicator on the housing of the spindle, not on the milling bed.

You want to measure the play in the spindle so lock the quill to avoid measuring the play in the quill.

Measure the play in all directions

Most mills (and lathes) have contact angle/tapered bearings and those bearings can be adjusted to reduce/remove the play.

Have a look at this thread Emco FB2 bearing replacement