BAZMAK-DIARY of a NEW SIEG SC4 LATHE

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I sold my sc3 with the blown board and the restored Advance lathe,added another $600 to the proceeds and bought the new Sc4.Also bought a good quality 4" 4 jaw,negotiated the freight and was given free of charge
A 7" faceplt and clamping kit,a 16mm precision keyless chuck for the tailstock
and an 11 piece carbide set of tools.Lathe arrived from Aussie stores Melbourne in 3 working days,in a very big box.Unpacked and managed to lift in position
by myself with no lifting gear.A serious piece of kit twice the weight of the Sc 3
I had modded and repositioned the existing bench,new full width worktop
and a 3" deep drawer at the LH side. (waste no space Gus).Just fits, now need to clean down and check everything out.Will keep you posted IMG_1316.jpg

lathe 01.jpg
 
Such a nice clean layout. I'm envious.

Only one suggestion.... build a metal tray for the table top to catch chips and oil. It makes clean up so much easier.

I too have drawers and a cabinet under my lathe as it helps to stiffen up the table top and it provides quick and easy access to tooling.

Good plan.
 
Looking great Baz. Nice tidy workshop too. Might have to tidy up my messy workshop after seeing yours.
 
I spent a week remodding the end of the workshop ready for the new lathe
Hopefully this is the cleanest it will ever look.I had a drip tray with the sc3
and found it an inconvenience.Chips trapped underneath etc,so have decided to try this lathe without.I dont use coolant and its a full melamine coated
top and splashback.Time will tell.Still in the process of modding the other end of the shed for the mill.List of things to do starting this morning. oororoo
(thats goodbye for now in Ozzie speak)
 
Hey ! Your shop is looking pretty good to me !! Lathe looks good, also.
Time to make more parts. :)
 
Looks a nice little unit.
My old Unimat V10P in near the end of its useful life so I'm looking for a replacement.
I've been putting it off because of the horror stories you hear about some of the rubbish out in the marketplace, so I'll be following this thread with interest.
I watched a video on Youtube of an SC4 and it seemed really loud. Have you found this to be the case?

Regards,
Alan C.
 
I was a bit concerned about the noise but its not too bad.Mainly from the gear chain to the leadscrew.With no tumbler reverse you cant disengage the leadscrew.So far i am very pleased with everything else.Horror stories of
chinese is old hat and mainly a thing of the past.Sieg lathes are much improved
and i am on my second.I also enjoy any tweaking
 
I sold the 6" faceplt with the SC3. The T slotted faceplt i made became part of the Rotary Table. I do like using faceplts so negotiated a &" one FOC with the
SC4. I had in mind to use it as the backing plt and fab a new T slotted one.
When i unpacked everything i was pleasantly surprised.The 7" one was a good quality substantial casting,far too good to start bolting T slots section to it.
A closer inspection and i realised there was enough meat to machine some T slots direct,so i set up on the mill and cut 4 T slots.Now a really useful item
Next,making chips. oorroo for nowfaceplt 02.jpg

faceplt 01.jpg
 
I had kept the 3" er32 collet chuck i made for use with the RT and planned to buy one for the SC4
However they were out of stock so i decided to spend my $100 on other things and make an adaptor plate.First job for the SC4.I took a 20mm slice of 4" cast iron and proceeded as the photos. The SC4 is slightly larger, twice the weight and twice the price but it makes the SC3 look like a toy.Very ,very impressed.Drilling the 22mm hole was only just doable on the SC3,bogging down all time No problem with this beast.Twice the depth of cut and it never even thought about it.Cross feedvery good,but a little slow.Will have to look at the gearing
Facing large Dias and nudging the speed up as you travel to the centre works well
Very solid ,smooth and rigid with no hint of chatter.1.5mm cut no effort.Unit is very quiet
with the only noise from the gear train.No easy way to reverse the leadscrew so power feed is
inwards or towards the headstock,no real problem
Tried the 3 jaw in 3 posns and the jaws in 3 posns.Marked the best one about 1/2 thou runout
The gap is larger between the spindle and headstock but they have supplied hex hd sets
so its still tricky to bolt on a chuck.Reverted to the tried and tested method i used on the SC3
M8 Studs to the chuck and Wiznuts. Much better.
Again no carriage lock that i can see and i thought i will need one using the power cross feed
Apart from cleaning off the grease and bolting it down i will use it as is and make minor mods
when problems arise.Gibs seem firm and smooth so will have to wait and see
Simple locks on carriage,cross slide and compound may be needed and a carriage stop?
So far very happy.I was happy with the SC3 but this is in a different league
ooroo for now
collet 02.jpg

01 chuck fix.jpg

lock03.jpg
 
The 4 way tool post was the same as the sc3 with the same small handle
that when locked was towards the lathe.So i made a better handle and skimmed the nut so the handle faced towards the operator.The sc3 had a tool height of 8mm and the sc4 was 10mm.The set of RCT tools i made needed
packing so i made a new double ended one machined to dead centre height
The originals i will remake or fit permanent packing.I also quickly made a
simple tool rack to hold all the commonly used tools

The sc4 stood heigher than the sc3 so i made a 3" duckboard.The lathe was also out of position,so i removed the splashback and made a simple motor cover and moved the lathe back 3".I had mounted the lathe so that the tailstock could be removed and max clearance to the leadscrew changegears
I changed the gears from fine feed to coarse feed and although the banjo design is very good with access from the front with spanner,the shafts were fitted with t nuts to make it easy.I still found it difficult having to peer round the corner.So i moved the lathe 3" to the right.Much easier access to the changegears but no room to remove the tailstock.I can live with that because of the 20" long bed.Lathe is now much more comfortable to use.Will try some single point screwcutting
The lathe is supplied with a good range of change gears for both metric and
imperials threads.Starting to feel much more comfortable using it and so far very pleased.Well worth the money
 
No more than a minute to remove one chuck and a minute to fit another
I found it slightly faster to change on the Myford with a screwed nose
Any particular reason for the question Regards barry
 
No more than a minute to remove one chuck and a minute to fit another
I found it slightly faster to change on the Myford with a screwed nose
Any particular reason for the question Regards barry

The reason is that I am really tired of the drive system on my Boxford when doing interrupted cuts.The inner v disc is around 100 mm diameter and rides on the spindle.Torque is transmitted via a key and two short pins in backgear bull wheel.It sounds awfull when working.If I had a spindle like the SC4 I would turn a v channel along the rim Diameter (aprox 200 mm) and forget about the back gear.Modern inverters do the rest.

WP_20150508_001[1].jpg


WP_20150508_002[1].jpg
 
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If i had the Myford i would still make a common backplate to screw on
and made to fit the chinese chucks and accessories etc then you have the best of both worlds.Lots of accesssories and at good prices.Also its easier to make
items to fit the chinese spindle mount than to a threaded nose
 
As an afterthought,when i did the the thread on the Advance lathe
It had a 1" BSF threaded nose.Found it too difficult to make an internall threaded adaptor plate so i machined the existing one to acceppt all the Sieg fittings,all chucks and faceplts then fitted both lathe and the RT.worked well
 
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Hi Barry I am thinking of retiring my old lathe and purchasing a Sc4 sieg ...you have had yours for some time now and am interested in how it has performed...are you happy with it and have you had any problems. regards clem in tassie
 
Hi Clem,im as happy as pig in s... No problems would highly recommend the unit for size,power etc
Main drawback is lack of tumbler reverse,means you cant disengage the leadscrew.Noise is minimal
but all from the leadscrew gearchain.I bought a 5" 4jaw self centering chuckwhich is an ideal size,does everything the 3 jaw does but holds sq bar concentric instead of hex.Makes making the turners cube a breeze.Along with the 4" 3jaw s/c and 4" 4 jaw ind. now does everything.Now can turn about 71/2 dia
I also made a diamond toolholder as described in Model Eng Workshop mag this month and plan to make a 3 way toolpost as described in the same issue.Will keep posting as and when i do anything of interest.Regards barry
 
I have just made a 3 way toolpost for the lathe.Will post a separate thread
However i wanted to do some rough milling with the Sieg and describe the results.It was easy to mount the piece in the lathe and wanted to try out the power x feed.The lathe is very good and worked well.However i would again note the following points
Having the compound assembly on a plate with 4 bolts on T slots is really good
for ease of positioning of the work to get full Y travel.Very robust but noise gets annoying at high speeds.Will attache a video to show
I cannot understand the Chinese mentality on design.With such a great machine the add a drive disconnect knob to the chuck with the leadscrew permanently engaged solely for use if anyone buys tyhe milling head attachment
Stupid i wonder how many mill heads they have sold,anyone buying a lathe of this standard would surely buy a a stand alone milling machine ???
But more stupid is not fitting a tumbler reverse to disconnect the leadscrew for very quiet running and to reverse the feed both cross and longtitudinal.Very big drawback for this lathe.When cutting the slots in the 3 way,i power fed in and then had to handfeed out.With a 6mm dia endmill and about 1000rpm the noise was excessive.If a later version with tumbler reverse and thread dial indicator was fitted as standard and the chuck disconnect removed i would take a loss on this one and upgrade
 
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