Member postings for David Murray 1

Mick

You shouldn't be using the settings tab to change between Metric and imperial. The option in the settings tab is for what units the machine is built in and should never be changed once setup. If your motors are setup in step/mm by changing this option you are moving the setting to steps/inch so you will be a big factor out.

To change the units use G20/G21 in MDI, or if you want it permanently to start in a particular units, in the Setting general tab, there is an initiation string with some G-code in it. Add G20 into the line and every time Mach starts up it will switch to inches.

I am using Win 7 32 bit with a UC300 and has been working fine for over a year. I think the issue with Mach and win 7 is you need an external motion controller - you cannot use a parallel port .

What you're describing sounds more like a coding issue. When the machine shoots off where does it go? Does it stop? I cannot remember which screen it is at the moment but on one of them you can click on each coordinate system and see the coords. You mentioned you typed G54 before your previous G0 move. What happens if you do the same for this move? Does the axis come to a hard stop and stall - have you got soft limits set?

Cheers

Dave

Over type engines are like a traction engine meaning you need hornplates and then everything must be carefully aligned and setup while working on a round barrel/firebox. Much more tricky trying to work around a curve and get everything well aligned.

With the under type the engine is almost a standalone unit so you can build in isolation and then bolt to the frame so generally everything is working in the flat which is much less complicated.

Hi

I was wondering if someone could help me with some drawings. I have embarked on building a clayton wagon. While looking through the build articles I notice that the differential uses Allchin parts. The drawings show the diff centre, but I cannot find any drawings of the bevels, pinions etc.

Would anyone happen to have a set of Allchin differential drawings that they would be kind enough to scan and email to me?

Thanks

Dave

If you want to put something on the machine have you thought about a mirror demister pad?

I upgraded the VFD for the spindle on my old Denford Triac CNC Mill. While setting up the VFD I noticed it had the option to display the %age power used so I set this up to feed back the number into Mach 3.

I've found it really interesting how little power is often required. Motor is 0.5hp and I was flycutting some cast iron at the weekend 0.5mm deep cut 2.5" wide and it was only using 12% at 500rpm

The biggest surprise for me has been the difference between a 'cold' machine and one that is warmed up. The same cut as above with a cold machine needed 64% power.

Even more surprising was that in the real cold weather earlier in the year (workshop about 8C!) - just turning the spindle over 2000rpm, needed over 95% power when cold and dropped to 40% when warm.

I've now got into the habit of warming up the machines for 10 minutes before I use them.

Has anyone else done the same with their VFD's?

That's interesting. I am planning to make the rear axleboxes for a clayton lorry from some lumps of Steel I've got kicking around and then make split bronze sleeves to go inside them. Looking at cast iron prices it is cheaper for me to buy some CI bar and machine them than it is for just the cost of the bronze. Looks like time to order some CI bar.

I've mentioned them before, but IGUS bearings are great - something like the M250 would easily do what you need -

**LINK**

How about IGUS bearings - **LINK**

Fantastic things, we used to use them under railway carriages for brakegear with no lubrication. Have a range for all sorts of environments. I notice RS sell them - **LINK**

Their M250 Range goes down to 1mm shaft size - https://www.igus.co.uk/product/5 and is good for general dirty environments.

Edited By David Murray 1 on 07/06/2018 12:09:15

Thanks for the ideas everyone.

I am now having a dilemma! Leave the floor concrete or wood! I suppose I could put the machines in and then if find it is cold put a wooden floor in later between them.

As it happens I am demolishing a 6ft high double brick wall to make way for the shed so I suppose I could lay a couple of courses of brick on top of the foundation slab and then bring the wooden walls down on top of them.

Hi All

The shed will be timber construction - mainly due to cost. I used to use a detached garage with a concrete floor and that was painfully cold on the feet in winter - hence why I was planning a concrete slab with 3x2 floor joists with insulation under the floor, probably covered in 30mm OSB or similar I was also thinking of putting a gravel filled trench around the slab to help water drain away and down. Roof will be a pent roof as I am limited to a maximum of 2.5m high

Hi All

Having had to sell all my projects previously to buy and renovate my home, I've just got a small corner of the garage setup as a workshop and started building a 2" Clayton. The carrot to the new house is that there is enough room for me to build a 4m x 2.5m workshop in the garden. I've been busy putting a new fence up and now knocking down the brick wall where the workshop will go and my mind is starting to think about groundworks. My plan is to build a 4" thick concrete base to build the workshop on and then 3x2 floor joists at 18" spacing.

The question is how low do I go ....... Should I dig down 7" so the floor is level with the surrounding ground, but the timber will be below the surrounding ground. Or do I only dig 4" down and then have a 3" step up to get into the workshop - I am thinking about having to get the mill, lathe and any projects I manage to build in and out of the workshop.

All thoughts/ideas/experience greatly received.

Cheers

Dave

Out of interest has anyone tried this - looks like a very useful technique if it works - **LINK**

Unbrako have a good PDF on the subject **LINK**

About 10 years ago a mate sold his Centec mill. It was agreed with the elderly gent buying it that we would deliver it for a small fee (Cardiff to Brighton) so we duly set off to arrive at the most stunning 3 storey town house. It was only when we got out we realised that the gentleman lived in a 2nd floor flat in this town house. The flat was full of books, an ML7, tooling etc. He must have been in his 70's and not exactly a muscle man so we ended up dismantling as much as we could, gingerly lifting the bits up the beautiful oak stairs one step at a time and reassembling it for him. We drove off very quickly worried that it may soon end up in the ground floor with all the weight in that flat!

Thanks for the advice. Had a quick go with Autosol and it is much better already. Will carry on again tomorrow

That should of course read coarse!!!

I had the tube of Autosol out last night but thought it might be too course. Obviously not so I will have a go later. Thanks for the tips everyone

I have an old DTI that I want to use for a tool setting project. It is a lovely 0.0005" bit of kit but at some time somebody has cut the mounting lug off it. Anyway, the problem I have is the front see through plastic window is all cloudy. I have tried whipping it over with acetone and no improvement.

Any advice on how I could clean it up? I did wonder about a bit of T-cut?

Richard

What a stunning example of Minnie. Fantastic workmanship and a lot of details cannot have been easy in this small scale. I am just in the process of steaming my own Minnie and running her for the first few times. Plenty of teething troubles along the way but she makes steam like it is going out of fashion! The water pump is my biggest headache which will not deliver. I've rigged up a temporary handpump and you can keep her in steam fro as long as you like. I will be taking the pump off and doing some more investigation. Here's a little video of my latest steam test last week with the handpump just out of shot.

**LINK**