Colchester CHIPMASTER -- making a TAPER ATTACHMENT for.

Here's a bit of background for the 1st 3 pics.
To start I used 1 x 3" CRS
squared up the ends to 4 inches and
milled the top to 15 degrees to mate with the underside of the
saddle and help to hold the part in good alignment when drilling
and tapping holes into the pad on the bed.

The parts were then put into the 4 jaw and leaned the same 15 degrees
and bored to accept 1.5" CRS-length was determined by full swivel of
the slide bar and enough room for cross slide movement/staging.

Next the blocks were drilled 5/16" and then mounted on the bed of the
Chipmaster, under the carriage with a 1/8" parallel as a spacer, to help keep both sides
even and clearance. The blocks fit under the carriage like a glove.
They were held in place with a large C clamp while drilling.
After all holes drilled the block holes were opened to 25/64"
and remounted on the lathe. The bed was now tapped with the blocks in
place as a guide, for 3/8 x 16 bolts.

Next I mitered the back ends of the 1.5" CRS bars
for more material insertion into the blocks and to get
an even length from lathe bed to the ends.
The bores were just a tad on the loose fit so I
did a bunch of center punches and then pressed them
into the blocks. Measuring them they were about .001"
difference between the 2.
Next they went for welding. I ring around the front
and an inch in the pocket at the rear.

With the blocks welded on I was able to line up the 15 degree pads
in the mill and milled the ends of the 1.5" rods to form a key, for
positive alignment with the slidebar assembly.

During this week at work I hope to mill the underside of the slidebar to fit the keys
and drill/tap the rods/slidebar for bolts.

Aren't the saddle castings for a Chipmaster identical to the much more common Bantam MK2?. If that's the case a Bantam taper attachment would fit the Chipmaster lathe.

Sag 180. While you are correct the Bantam/chipmaster
taper attachments should be the same. Up here in Canada/USA
they are basically non existent. They might be a bit more available
down in OZ, and I don't know what prices there would be.
But for us it would be from Ebay.uk or home workshop machinery in
the UK. I just looked and there are a couple listed-not even complete
for 360-450 GBP and one had the shipping listed @ 216 GBP.
I'm into my project for 220.00 CDN, including 100.00 for the
Sheldon slide bar assembly and slider block. I threw the carriage
mounting bracket in the scrap bin-too many parts missing.

So we're getting close to complete now.
Pic 1 is the underside of the slider bar-base milled to mate with the support brackets,
and holes drilled and tapped.The swiveling slide bar assembly is from a Sheldon lathe
from the 40's or 50's.
Pic 2 is the slide bar shimmed and bolted down. The assembly is extremely rigid.
The base bar is parallel to the lathe ways within .002 both horizontally and vertically.
Also the swivel/slide bar has been added. The swivel bar has had the curved slots
extended and a couple extra tapped holes added to each end of the base bar to
increase the taper range to 17-1/2 degrees either way.
Pic 3 is the cross slide adapter made from 1/2 x 10" 6061 and drlled to mate with
existing holes in the cross slide-the Chipmaster has lots of holes.
The 1 bolt sticking up a bit is on account of a slight miscalculation in hole
layout. So is filed out to allow the bolt to fit. Will add some epoxy and re-countersink
later.
Pic 4 is the underside of the slide block.
The tapered gib was missing, so made a new one in bronze.
Quite simple really. ~It's only tapered in 1 direction.
It slides beautifully.
The hole has been opened with a step bore to accept
the adapter stud. Thats the pc. sitting beside it, which
I'll fit tomorrow and then give it a test run.

The taper attachment is NOW FINISHED.
Pic 1 is if the completed and installed drive stud for the slider block
Pic 2 is of everything assembled and in place the slide block connects to
the cross slide bracket with a 1/2-13 button head bolt.

I did full mock up tests with hand feed and power feed
with slide bar set at tapers of 1 and 4 and 8 and 17 degrees.
Couldn't discern significant increase in drag towards the limits.

Pic 3 is a 20 thou cut with fairly high feed rate on 1-1/2 6061 aluminum.
The taper is at 16 or 17 degrees.

Nice work, how do you disconnect the cross feed screw?



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The taper attachment from the old Roundhead Student/Master fits the Bantam /Chippie......I have half of an attachment ,and a friend had the other half ...it was a Mexican standoff......Unfortunately ,at that point he died,and his kids got in a house clearer ,as the house sold the day after the funeral....Thems the breaks when youre old.

In the last post pic#2 shows a nut with ball oiler 11/16 socket and
shes out and just as fast going back. Made a 1" aluminum plug-fits
into the counterbore snug and keeps chips out.

John.k
What you have to decide is do you want a taper attachment for your lathe? An able able to use IT.
I think I've demonstrated here that YOU can do something about it.
I don't kn ow which half of one you have. But if you've got the slide bar assembly, then you're
on your way there. You just have to take some measurements and decide what aproach you want
to take to mount it. If nothing else the way I did it should give you some inspiration.
If you don't have the slidebar assembly, but mointing brackets, I'd say ditsc them or trade
them for something you could use and find yourself a slidebar assembly-base/swiveling slide bar and
slide block with enough length that will suit what you'd like to be doing with it.
If you'va a lathe and mill you're most of the way there. And a welder, edven better.
If not no worries, I didn't spend too much for the welding I had to get done.
So ... Do YOU want a taper attachment or not?