2AM: I wonder if the table saw will wake the kids...

[10bulls]

The temptation was too great, so I spent last night assembling the beastie thus far.

I was dreading this stage a bit as being the first time it's all gone together, major design flaws should show up. As it happens there were no nasty surprises. Whew!

I have roughly aligned the Y (gantry) rails and the carriage slides a bit stiffly, but without binding. Hopefully with a more thorough alignment I can free it up a bit. I want to get hold of some dry silicon lube to see if that helps too.
Can anyone suggest a UK supplier? I'll check out RS & Farnell first I guess.
All in all I'm quite pleased with the gantry. It certainly feels rigid.

The base frame, bearing blocks and X rails were hastily thrown together and another big sigh of relief. It all lines up..., well mostly!
It certainly looks a bit more imposing than the bunch of scrap metal with holes that has been littering my workbench, for the past few weeks.
This is also the first time I have seen the X bearing design in action. Although the rails are not fixed nor aligned it appears to work in concept. We'll soon see!

There's still a heap of work to do getting the thing lined up and moving smoothly...better stock up on some 'Midnight Oil' ( "how can we sleep while our beds are burning?"...)
First though, I think I'll finish off some of those 'fiddly' bits next, then give the garage a bit of a sort out...I gotta find a home for this hunk-a-junk!

[MrBean]

Looking good...
I got some "Dry PTFE" spray from screwfix. It's meant for blades and cutters. But works wonders on my Y axis rails.

Midnight oil would be ok if used between 23:30 & 00:30. Outside of these hours the "midnight" effect of the oil becomes very volatile. A mate of mine was using "midnight" oil at around 02:00. Next thing he knew, 2 days had passed. Seems that the oil had lubed up the space-time continuum, causing him to slide into the future. Yeah, can be slippery stuff. If you must use midnight oil, then tie yourself to somethimg solid. I.E. Not my router....

Regards Terry.....

[xairflyer]

They machine is coming on well,

Looks like you have the same lathe as me from chester machine tools, most useful thing I bought in years.

Keep up the good work.

[10bulls]

Originally Posted by MrBean Looking good... I got some "Dry PTFE" spray from screwfix. It's meant for blades and cutters. But works wonders on my Y axis rails.

Thanks for the tip! I've had a Screwfix catalogue sitting in front of me for a while. They're always so rubbish when I want to buy something as strange as 'screws' from them, I'd not looked further. I see their drill bits (blacksmiths and forstener bits) look quite reasonable.

Midnight oil would be ok if used between 23:30 & 00:30....

You're weird!

[10bulls]

Originally Posted by xairflyer They machine is coming on well, Looks like you have the same lathe as me from chester machine tools, most useful thing I bought in years.

Thanks!
Yeah, it's a Chester mini lathe. I wish I'd bought one years ago. I had some fun and games with missing parts but Chester were quite happy getting replacements sent out...even if they were the wrong ones.

Have you done any modifications to yours yet? There's certainly a few things that it could do with.

Congratulations with your recent successes!

[santiniuk]

Hey 10bulls,

hows it going ?

Have the 3am nights seen the end to your cnc bashin ?

[xairflyer]

Thanks 10bulls,

I hav'nt done any mods to the lathe yet except cut about 1" off the end of my tailstock chuck arbor, so I can use all the movement.

First mod i will do is a cam lever for the tailstock as it is difficult to get at the nut when close to the cross slide.
Great little machine for the money, another useful item is a cross slide vice (you can get them in machine mart) which converts your pilar/bench drill into a milling machine with a cutter in the chuck.

[10bulls]

Originally Posted by santiniuk Hey 10bulls, hows it going ? Have the 3am nights seen the end to your cnc bashin ?

Still alive! Flu, work and family have conspired against me and put tinkering on hold for a couple of weeks. Back on the case now. Mama Dragon has taken the dragonlets to the dragon-in-laws this week and has taken the digi camera with her, so a photo update will have to wait I'm afraid.

I've made some bearing blocks (2 skate bearings with spacer between) and mounted the lead screw on the gantry, then had a few moments jolly wooshing it back and forth with my cordless drill. I'm going to mount the servo motor to it tonight which should mean the mechanics of the Y axis will be pretty much complete.

I've bought a long timing belt (T2.5 16mm wide, 1300 pitch length) to connect the 2 X-axis lead screws together using some pulleys I had.
After a *lot* of phoning round and comparing prices, the place I ordered them from was:
Transmission Developments: http://fp.transdev.plus.com/index.htm.
I was very impressed by the price, prompt delivery and large stock. I am also most grateful to the guy at APG Developments Ltd (0)1634 722420 for advice. He CNC manufactures (among other items) toothed pulleys (very reasonable price) and was most helpful and quite sympathetic to homebrew CNCing.

T2.5 profile is not ideal and I can feel some backlash with it, but I already had some pulleys and I don't think the backlash is going to cause any problems once the belts are tensioned properly. As it turned out, it wouldn't have been much more expensive to go to HTD3 profile and buy new pulleys, as the belt would have been cheaper. The belt cost ~£22 and is the single most expensive purchase on the project thus far. So there's real money invested in this enterprise now...no turning back!

[10bulls]

Originally Posted by xairflyer ... I hav'nt done any mods to the lathe yet except cut about 1" off the end of my tailstock chuck arbor, so I can use all the movement. First mod i will do is a cam lever for the tailstock as it is difficult to get at the nut when close to the cross slide. Great little machine for the money, another useful item is a cross slide vice (you can get them in machine mart) which converts your pilar/bench drill into a milling machine with a cutter in the chuck.

I chopped down my chuck arbor a couple of nights ago with my trust angle grinder...much better!...gotta do my dead centre next.
I'm with you on the tailstock cam-lock, that bolt is a pain! I was going to make the one on www.mini-lathe.com.

I bought a cross slide vice a while back for that purpose, but it didn't work out. My el cheapo clarke drill press has serious play in the spindle when extended and the cross slide hits the pillar in most positions
I bought a vertical slide for the lathe for milling, but haven't got around to figuring how to attach it yet.

[xairflyer]

yeh the spindle needs to fairly good and true, when I bought my bench/pillar drill I tried different makes in the shops by pushing and pulling at the chucks and got them to connect them up so I could see them spin just to see how good they were, and eventually settled for a Sealy 16 speed version which cost me £150 but it a very good drill with 16mm chuck.

[10bulls]

I managed to squeeze in a bit of work on my machine over the past week in between work and digging my allotment ready for me 'taters (ooh!...oww!...my back!)

I made a motor mount for the gantry and mounted a likely looking servo to it. The coupling is a piece of clear PVC pipe (from the home-brew kit I think...if my nose doesn't deceive me). Ugly as sin but the screw turns around and I can send the carriage wooshing to and fro now via the servo and a car battery charger. It struggles in a few places...I still need to tweak the alignment and get some dry PFTE spray. The threaded rod is dead kinky (aren't they all!!) and results in jerky movements (as does eating too much jerky! ). One of the first upgrades is going to be trapezoidal leadscrew I fear.

I made another 2 bearing mounting blocks for the X axis, turned a pair of delrin drive nuts and mounted the leadscrews. I added a motor mounting plate from which the motor and belt tensioners sit atop of steel stand-offs. I went with my biggest, coolest servo for the X axis. (gotta get me an R2D2 model to sit between those X-wings!) Pulleys and belts attached it was time for another whoosh! Amazingly it all seems rather robust and the carriage moves it's full range. So that's the X and Y axis pretty much mechanically complete!!

Having got the servos mounted I'm changing tack a little and am going to go with steppers and PICSTEP. I doubt my old printer steppers will cope with my design, so I've managed to find a supplier of steppers that seems quite reasonable... ~£40 for 220Ncm and £30 for 180Ncm motors (They are both 2.5A phase, 8 wire, 1.8 step angle jobbies). Does this sound an OK UK price?
If all goes to plan, I can refit the servos when Alan kindly releases PICServo, then I'll have 3 nice steppers and drivers all ready for my lathe CNC conversion.

I've still got the Z axis to build. I've cut out all the aluminium plate sections, but there's some serious precision machining ahead which I'm dreading. To postpone this somewhat I'm going to get the electronics sorted first. I also intend to make another detour and finally mount my vertical slide on my lathe and have a go at using it for milling. More on that later.

[xairflyer]

That machine is a really brute, now that I have been playing with my machine I can see I will have to start work on a new one designed to cut alluminium like yours.