Thread: AL250G gearbox inspection for setting up.

Better safe than sorry, I'd check it first - it is Chinese. From memory, I think the plates have a through bolt, so the plates are meant to be bolted to the stand first otherwise you can't get to the bolt heads atop the plates to tighten them. Why don't you copy the recent stand example in mounting the channel, I think it was for the Schaublin. The tray can still be mounted on top and if adjustment screws are installed on each corner, it should give very fine adjustment for levelling.

Brian, check the dimensions as in my case, the book was wrong. I pushed some transfer punches up though the holes and measured point to point. You could turn up some rods and cut some tapered points as your first job to measure against. You don't need to be precise so you would be OK to do this without the lathe bolted down.

Everone talks about finding sand but myself and another user both report not finding sand in the 320g so I would not be too concerned about this. You have enough to do. I would clean up the rest of the lathe and see if you find any debris before you worry too much about opening it up. I may be wrong but I thought your lathe came from Taiwan which I plies better quality.

As far as the welding goes, I tacked everything up first before welding it out. This did not stop me stuffing a few up that I had to adjust with a grinder and redo. I spent a lot of time getting the cuts accurate when cutting the parts out. Check dimensions, spot weld, check diagonals are the same length on any square or rectangular assemblies.

As far as your base plate, sounds like mine was different. If it has to be assembled, I would try and do that while the lathe was suspended above your stand.

The 20 minute run in sounds about right. That is what was recommended when I rebuild the spindle on my last lathe. Check things are not too hot to the touch. I am sure they won't be. After a few hours work, my old lathe bedded in nicely and sounded so sweet!

Thank you th62 and rodweb,
It is always reassuring to me to get some practical feedback.
I'm looking forwards to catching up with you Rod, now my wife is back home from hospital. It's a bit difficult to visit your place late afternoon midweek, since the drive back to the Coast is hell on wheels at peak hour. I'm available most weekdays (not this Thursday--going fishing) until about 2pm and weekends any time, (except this Saturday) if there's any other times that might suit you??
Any wonder this stand is taking so long!!
regards Brian

Hi Brian,
Will the stand be bolted to the floor? With my stand i made it adjustable at the floor, it concerned me that with adjustment bolts at the machine bed the stand may twist rather than the lathe bed untwisting, or worse not twist to start with then move slowly over time. Adjusting of the concrete means that the plane you are adjusting off is fixed (well as good as in this case). Saying that I think there are many stands with adjustment at the bed so it should be fine. Probably just my mind over thinking things......

Cheers,
Ew

Hi Ew,
The stand will be bolted to 2 piece of 50x50x6 MS angle (front and back)which will bolt through the floor into 3-4 joists and directly under them are two 50 x 240 F25 KD hardwood bearers. The angle can be removed at the front to allow me to push the engine hoist forks in under the bench.
I can shim under the angle to get the stand level--then fine tune the lathe bed which will be bolted to the 150 x 75 x7 channel on top of the stand, with (4) allen screws with locknuts on them under the channel. There will be adequate space to slip my hand under the top of the stand and adjust the allen screws with an allen key, then lock them in place and if necessary locktite them.
I have to be a little more creative because I dont have the traditional concrete floor.
Thanks for putting some effort in 'overthinking'
regards Brian

Originally Posted by Ueee

Hi Brian,
Will the stand be bolted to the floor? With my stand i made it adjustable at the floor, it concerned me that with adjustment bolts at the machine bed the stand may twist rather than the lathe bed untwisting, or worse not twist to start with then move slowly over time. Adjusting of the concrete means that the plane you are adjusting off is fixed (well as good as in this case). Saying that I think there are many stands with adjustment at the bed so it should be fine. Probably just my mind over thinking things......

Cheers,
Ew

Originally Posted by Briangoldcoast

Thank you th62 and rodweb,
It is always reassuring to me to get some practical feedback.
I'm looking forwards to catching up with you Rod, now my wife is back home from hospital. It's a bit difficult to visit your place late afternoon midweek, since the drive back to the Coast is hell on wheels at peak hour. I'm available most weekdays (not this Thursday--going fishing) until about 2pm and weekends any time, (except this Saturday) if there's any other times that might suit you??
Any wonder this stand is taking so long!!
regards Brian

Brian, weekends are generally fine but give me a week or so as I am fitting a DRO to my Mill so everything is out of position and I can't move in my shed. I am about half way and hope to get it finished and some plumbing done to get coolant from the coolant pump on the lathe to the mill over this weekend.

If it makes you feel any better, I put about 7 days of effort into my lathe stand and it is still not finished.

Good Morning Brian,
I also have a 250G and lots of forum-ites have given me great advice.
Mine came with the blue stand shown in the dogalogue. I have set it on 1/4" rubber sheet on the concrete floor without anchors - but it is bolted to a 4x3 upright that brings the power down from the roof. I siliconed around the tray holes before lowering the machine onto the stand (with a BobCat!). It is slightly unlevelled for coolant to flow toward the back and the right. The coolant 'system' is a Toyota windscreen washer with a solids drain trap.
Problems
I have had to remove the both the lead screw and carriage apron gearboxes to clean them out and seal them up well as they filled up with coolant. Removal of the main gearbox cover will soon tell you if it's contaminated - you can see the bottom easily with a torch. Mine was in good condition, but I changed the oil to EP90 gear oil with nulon additive - that made it much quieter.
The recess in the spindle labyrinth seal they provide to remove the chuck attachment bolts is far to small for Aussie phat phingers. I had to remove the spindle (not easy) so that I could machine a larger recess in the seal collar. While it was removed, I fitted quality Japanese tapered rollers to the spindle. That also reduced the noise.

I have also fitted a QCTP with adaptors that also allows me to still use the Std tool post for other things. I have also indexed the face plate and made a drawbar to fit the ER32 collect chuck (from the mill) into the spindle. The drawbar is also made to allow removal of the chuck without using the dreaded brass hammer (I don't want to damage the new tapered spindle rollers).

I'm within striking distance of the Coast - happy for you to drop by if you want. Regards, Daryl.

HI Rod,
Your time frame works well for me, and I will stay in touch to follow your progress.
I know what you mean about a mess. I have a full sized vertical drawing machine I love, in the only practical place for the 250g.
I have to totally disassemble it and put it inside, much to my ever loving wife's dismay, tempered only by my promise to clear ouit half the furniture in my office to let it live there.
There's an ancient binks bullow airless spray painter and an electric pottery wheel, that need a 'decision' to be made on them, since otherwise there wont be enough room for the car--etc etc--I'm sure you know what I mean.

Hi Daryl,
Your adventures fascinate me and I feel sure my set up will be a lot more practical if you are willing to share some of the details.
You're right--we are not a world apart, and once I get on top of some of the pedestrian stuff that's getting in the way of my 'obsession' I will contact you, and look forwards to meeting you.
regards to you both
Brian

I think you need to go all out an build a stand which weights more than the the lathe

welder!!
Now THAT is a stand!!
Clean and simple and no way that will tip over or need bolting down. I'm impressed.