Member postings for Michael Cox 1

Hi Leanne,

I think John has covered most of your points but with regard to the side to side play on the leadscrew you have two options.

1. Loosen the bearing blocks at either end of the leadscrew and see if you can push them closer together to remove the slack. You will have to re-align the bearnig blocks to ensure that the leadscrew can still rotate easily and that on closing the half nut the leadscrew does not move. If there is not sufficient movement in the bearing block to take up the play in the leadscrew then you could elongate the holes so that then can move horizontally to take up the play.

2. The other method of taking up the play is simply to make a washer the correct thickness to take up the play. This is the easiest solution if there is a lot of play.

I think there are instructions for aligning the leadscrew in the ArcEuro guide.

Mike

Hi Paul,

I had two windscreen wash pumps in my scrap box. One was marked SEIM and was made in France. It was a gear pump with plastic gears. The other one was marked Linwood and it had a rubber impeller. I was not sure of the compatability of rubber with oil based coolants so I opted for the SEIM pump.

The SEIM pump has been in contact with neat mineral oil for over 4 years and it still works well.

I avoid the use of aqueous coolants whereever possible because of the rust problem (and staining of metal surfaces that slide together). I generally use a 50/50 mixture of engine oil and white spirite as coolant.

Mike

The benefits of using a windscreen washer pump are twofold. Firstly with any sort of drip system then sooner or later the drip tray or catch container becomes full of coolant that has to be removed and cleaned up. This is not always easy and a pump enables the fluid to be recirculated. The second benefit is that the feedrate is readily adjusted by varying the motor voltage. This is not always easy using the sort of pinch vales used on plastic tubes.

Mike

You can use a windscreen washer pump to pump the cooolant/cutting fluid to the workpiece. The motor speed can be varied from drops to a jet by regulating the motor voltage. An article on this was published in MEW No 181 page 20.

Mike

Hi Francis,

I am not quite sure what you are suggesting with regards to the flycutter but as long as the angular relationships of the cutter are preserved (ie. the tool points down at an angle of about 12 degress and is at 12 degrees to the tangent of the cutting circle) then it shoulf work OK.

Mike

Hi Francis,

One problem with multi tool face cutters is getting all the tools at the same protrusion so that they all cut.

You might also consider a fly cutter with the tool mounted tangentially. My experience is that this arrangement gives better surface finish and faster removal rates than conventional flycutters. More information on my cutter can be found here:

**LINK**

Mike

Hi Baldric, I made myself a type two ball turner which I have used quite often and seems to give satisfactory results. It is based on the Steve Bedair design but I have modified the position of the cutting insert so that complete balls can be turned. More details are here:

**LINK**

Mike

Hi Chris, I did not go to Ally Pally so I have not seen this tool. Can you provide more info?

Mike

I have just entered 'cut knurling tool' into ebay. It produced three responses all of which were conventional knurling tools. I then entered simply 'knurling tool' and this produced around 100 items all of which were conventional knurling tools.

Mike

Hi John,

Beeline Engineering can source any Gates belt. Their website lists many non toothed belts.

Mike

Hi John,

The agent for Gates belts in the UK is Beeline Engineering (www.beelineengineering.com). I have dealt with them and they have been very helpful.

I did a belt drive conversion on my Seig X1 mill and used Gates belts, see:

http://mikesworkshop.weebly.com/mill-belt-drive-conversion.html

Mike

You can buy the non tilting column from Machine Mart as a spare part and add it to the Arc X1L if you want to. I have never tilted column on my X1L and it is bolted up tight and it has never moved since I first trammed the mill.

Mike

Hi Chris,

I have had an X1L from Arc for more than 5 years. I have used it to machine mostly mild steel and it has coped well. The mill has only a 150 watt motor so it is relatively easy to stall and this limits the depth of cut. This is not a real limitation since you can always make multiple passes with lighter cuts to achieve the same result. It just takes time.

The basic machine has some minor niggles. The locking screws for the y axis are right underneath the table and are difficult to get at. This can be easily improved. The gears are very noisy (on my machine it was mainly the selectory mechanism rattling). I eventually replace the gears with a belt drive. I also replaced the x and z axis feadscrew bearings and fitted a motor drive to the x axis. Details of these mods can be found here:

http://mikesworkshop.weebly.com/mill-modifications-and-tooling.html

It is a great machine.

Mike

Hi Wolfie,

Yes you can buy long series drills from good tool suppliers. Arc do metric ones. Try Tracy tools for imperial one.

Mike

Hi Wolfie,

I fitted stops to my small X1 mill. I think you could do someting similar on yours, see:

http://mikesworkshop.weebly.com/mill-table-stops-and-locks.html

I hope this helps

Mike

I have been using stainless steel containers as crucibles for a long time without any problems due to perforation. I always heat a new container in the furnace for several minutes to build up a oxide layer before using it to melt metal. I believe this oxide layer protects the metal from dissolving in the aluminium. I am careful not to scratch the sides of the vessel when stirring the molten aluminium.

At the end of each casting session I clean the crucible using hot caustic soda solution. This dissolves any aluminium stuck to the crucible. Once clean the crucible is inspected for any damage to the oxide layer. If there is damage to the oxide coating then I would discard the crucible.

Some of my stainless steel crucibles have been used for 30 melting sessions.

Clay/graphite crucibles also have a finite lifetime and if they fail in use this is most likely to be due to cracking. I think that this type of failure is potentially more dangerous than a small pinhole developing in a stainless steel crucible.

Mike

The appearance of some zinc alloys is very similar to aluminium alloys. All the hard drives I have had have been aluminium. There are two ways of distinguishing aluminium and zinc.

The first is based on the density. Zinc is much heavier than aluminium for the same sized piece (zinc has a density of 7.1 g/ml and aluminium 2.7g/ml) Density can be easily determined by weighing dry and then immersed in water.

The second test is based on the fact that zinc will dissolve in dilute acids such as vinegar liberating hydrogen whereas aluminium will not readily dissolve. So just sprinkle a little vinegar on the metal. If it reacts and froths it is probably zinc. Note this test also distinguishes aluminium and magnesium alloys (see the video link in Terryd's response).

In summary, if the metal is light and reacts with vinegar then it is probably magnesium based, if it is heavy and reacts with vinegar then it is probably zinc based, if it is unreactive to vinegar then it is probably aluminium based.

Mike

The term tangential arises because the long axis of the cutting tool is approximately tangential to the arc described by the tip of the rotating tool.

The alternative tangential fly cutter mentioned by Chris Stephens that is describedc in HMEM suffers from one problem in my experience. In most flycutting the tool is cutting intermittently and the hammering cause the cutting tool to slip in the holder unless the motion is restrained by a positive stop.

Mike

I find scrap aluminium everywhere. Possible sources are old carpet joining strips, old aluminium furniture, old shower rails, old car wheels, old hard drives etc.

The advantages of aluminium are that it is plentiful, it melts at a relatively low temperature (circa 650 degrees C) and it can be melted in easy to find stainless steel containers. Furnace construction is not critical because the temperatures are fairly low.

Once you move to melting brass then the melting temperatures are much higher (circa 1000 degrees C). The furnace construction is more critical, special clay graphite crucibles (expensive) need to be used and zinc fume (toxic) is troublesome. The potential dangers of the process are large.

I would advise try aluminium melting and casting first and then move to brass once you have some experience.

Mike

Hi Alan,

I have tried melting aluminium cans. The main problem is that being thin the cans have very high surface area to volume and when melted there is a great deal of dross and a corresponding low recovery of usable aluminium. Recovery is slightly better if you use Lo Salt as a flux.

Cans are also made from pure aluminium. This is very soft and gummy so it does not machine well. Adding a little copper (circa 2-4%) improves the machinability of the metal.

Speeder builder5. I think you would get a good recovery of brass from scrap taps and fittings.

Mike