Scotch All Round

[PaulR]

The way that Kozo used banjo fittings on his train designs was to turn a groove on the inside of the ring, so the alignment of the cross holes did not matter. Or, if the ring is a loose fit on the post, with the washers making the seal, then no groove needed.

Hmm, definitely food for thought - thank you!

[PaulR]

Seems I'm going to have plenty of thinking time... my 2 month old lathe has just developed a fault, with the chuck spinning even when the speed control is set to zero which gave me a bit of a surprise when I turned the machine on. The speed is going up and down all over the place when the pot is turned, must be faulty or maybe something else on the circuit board. 

[crueby]

Ouch, thats not good! Something wrong in the electronicalization stuff...   
Hope its something simple like a loose connection.

[Kim]

Might be a dirty pot.  Those things can get dusty inside and it really messes up the sweeper arm.  Before you go too far you might just try blowing the dust/dirt/chips out of the pot and see if that helps.  The other thing we always used to do was spray some WD-40 in the pot to help clean the contacts.  Maybe not the official right thing to do, but it usually worked for my applications!

Hopefully, it is something simple and you'll be back up and running soon.

Kim

[PaulR]

Might be a dirty pot.  Those things can get dusty inside and it really messes up the sweeper arm.  Before you go too far you might just try blowing the dust/dirt/chips out of the pot and see if that helps.  The other thing we always used to do was spray some WD-40 in the pot to help clean the contacts.  Maybe not the official right thing to do, but it usually worked for my applications!

Hopefully, it is something simple and you'll be back up and running soon.

Kim

Yep, I hope it'll be something straightforward. I did try cleaning around the pot but it made no difference. I'm not going to take it apart or do anything that might invalidate the warranty as I only bought it in December so I'll wait for a reply to my email, hopefully on Monday.

[PaulR]

The way that Kozo used banjo fittings on his train designs was to turn a groove on the inside of the ring, so the alignment of the cross holes did not matter. Or, if the ring is a loose fit on the post, with the washers making the seal, then no groove needed.

Hmm, definitely food for thought - thank you!

I think this simplified version might work with just the end of the post widget being threaded to attach to the valve cylinder (being a nice sliding fit through the support and the frame). The 3D view of the part has the right proportions, the bottom sketch definitely doesn't!

[PaulR]

I managed to finish drilling the holes through the four brass cross-members before the lathe went kaput but now I'm at a loose end so I had a quick work out with Mr Hacksaw, a 2" bar of BMS and a 3/4" brass square. What fun.

Here are those bits with the others temporarily assembled. The flywheel will sit between the frames, the air will come up through where the heads of the two screws are just visible and the spool valves will allow it to cross alternately to the piston side and exhaust out the ends of the valve cylinders. The valves and pistons will be operated by scotch yokes so it'll run in either direction depending upon where it's started. That's the theory anyway The timing will be set via the crank disc on the piston side as there isn't enough thickness to fit a grub screw in the disk on the valve side (which I plan to solder on).

[Admiral_dk]

I've been sick so a little late to 'the Party' ....

First : Contact the Seller as the unit is under Warranty - that most likely is Void, the moment you open anything !!!!!     

Under NO Circumstance use WD40 to Clean Pots => they do NOT survive this 

Why ? - you remove the protective layer inside that is there to protect against Oxidation of the Resistive layer the Wiper contacts.

Even when you actually get the right stuf for cleaning Electronics - they ALL damage Pots .... (with two exceptions) ...!

So what to do if not under warranty any more ?
Use one of the two Products that contains a new protective layer in the spray-can or have two different spray Cans .... the first is a cleaner and the second is the Protective sealer. Very few companies carry the later product ...!!!
Here in Denmark that would be Contact 60 and Contact 61 (can be bought more or less in the rest of EU).

Best wishes

Per             

[Sanjay F]

Oh no, very sorry to hear that, it must be so frustrating

Where did you buy the lathe from, was it local or delivered? 2 months is no time and yes, definitley sounds like it should be a straight swap under the guarantee, its just a pain getting in sent back and getting another.

There seems to be several rebadged versions of the Sieg machines, with each supplier doing their own checks and mods I think; Warco do one and I had Axminster versions of both the Sieg lathe and mill, bought secondhand and funnily enough I replaced the pot on the mill several times - not something you want to be doing on a new lathe though.

I hope you get it sorted soon and are back machining!

[PaulR]

I've been sick so a little late to 'the Party' ....

First : Contact the Seller as the unit is under Warranty - that most likely is Void, the moment you open anything !!!!!     

Under NO Circumstance use WD40 to Clean Pots => they do NOT survive this 

Why ? - you remove the protective layer inside that is there to protect against Oxidation of the Resistive layer the Wiper contacts.

Even when you actually get the right stuf for cleaning Electronics - they ALL damage Pots .... (with two exceptions) ...!

So what to do if not under warranty any more ?
Use one of the two Products that contains a new protective layer in the spray-can or have two different spray Cans .... the first is a cleaner and the second is the Protective sealer. Very few companies carry the later product ...!!!
Here in Denmark that would be Contact 60 and Contact 61 (can be bought more or less in the rest of EU).

Best wishes

Per             

Thanks for this, I'll see what the supplier comes up with tomorrow. I only bought the machine in December so I'm not taking anything apart

[PaulR]

Oh no, very sorry to hear that, it must be so frustrating

Where did you buy the lathe from, was it local or delivered? 2 months is no time and yes, definitley sounds like it should be a straight swap under the guarantee, its just a pain getting in sent back and getting another.

There seems to be several rebadged versions of the Sieg machines, with each supplier doing their own checks and mods I think; Warco do one and I had Axminster versions of both the Sieg lathe and mill, bought secondhand and funnily enough I replaced the pot on the mill several times - not something you want to be doing on a new lathe though.

I hope you get it sorted soon and are back machining!

Cheers. I did a 90 mile round trip to pick it up and save the £75 delivery charge. The packing crate was nailed, stapled and screwed together and was a splintered heap by the time I got the machine out so obviously I didn't keep the packaging (have to admit it was well packaged though). We'll see what they say.

[PaulR]

After two calls with the supplier, the likelihood is a faulty component on the PCB and a new board has now been despatched. Excellent service again from Arc Eurotrade!

[Sanjay F]

Ah yes, Arc are excellent. As suspected, it had to have been the PCB. I think your version will be updated from the oldie I had, but it'll be a relatively simple job to wire in.

Mind you, this is coming from the man who installed a new motor on his mill to discover it was rotating the wrong way round! 

[PaulR]

New PCB fitted and... no change, must be the pot, new one on its way.

[PaulR]

New pot fitted and we're up and running again. Hope to get some progress tomorrow!