|LaymarCrafts Woodturning||Hints & Tips|
|Mini Gripper Chuck, Support|
I think the Craft Supplies Mini Gripper is a fantastic little Chuck (if that is in fact what it is) that is both simple and efficient, every Woodturner should own one.
Used correctly it is very safe and can support many sizes and shapes of Wood for all manor of Turned Items, I regularly support Blanks of Oak up to 250mm x 50mm. (10" x 2")
The one problem is that it would not safely fit my Lathe, two versions are available, Screwed ¾" x 16tpi for Fitting direct to the Spindle or with a Morse Taper (both #1 & #2 are available). This Thread Size is not the same as that on my Lathe, Oh! when are Manufacturers going to standardise on a Thread Size for Lathes????
The use of a Morse Taper fixing is not to be recommended when applying Cutting Forces from the many different angles that occur when Turning using this Chuck, for this reason the Gripper is available with a Long Bolt to enable you to clamp it in a Hollow Spindled Headstock, here lay my second problem, my Spindle is Solid at the back end and therefore not suitable for this method of fitting either.
Not being one to give up so easily, I new I had a spare Morse Taper (#2) carrier from my old Chuck System that I knew fitted into my APTC Chuck system and this became the basis of my solution.
The illustration above shows how the Gripper fits into the Morse Carrier and the protrusion of the Gripper's Morse Taper out the rear of the carrier. The end of the Gripper is drilled and Threaded so there was provision to clamp the assembly firmly in place, if used like this the Gripper could easily come out of the Holder or the Headstock Spindle during use..
I fitted a suitable sleeve (I used a Gas Pipe Barrel Connector) over the protrusion, then with a Set Bolt and Thick Washer clamp the assembly tightly together, you need to make sure that the sleeve is at least 5mm longer than the amount the Morse Taper protrudes through the Carrier so that you do not "Bottom Out" when fully clamped up.
As I was to make this a permanent item I added a few drops of Thread Lock to the Set Screw before assembly which is now ready for use and totally safe and adaptable for those Lathes that are not accommodated by the original design and you also have a Chuck System that will take a #1 or #2 Morse Carrier.
Perhaps the Guy's at CS will set there mind to adopting this solution to open up the number of potential users and maybe show there gratitude. I await your call CS.
In a recent discussion on the rec.crafts.woodturning Newsgroup on the Web, there was a question relating to the use of a Jacobs Chuck in the Lathe Headstock Spindle and the fact that it kept coming loose.
It is important to recognise that any Morse Taper Fixture is primarily designed for Compressive Forces i.e. a Force that works to "Push" the Male Morse Taper into the Female Morse Taper Holder.
It is both un-safe and therefore un-wise to use it in any other way, the system described above works in exactly the same way for any Morse Taper mounted item including a Jacobs Chuck allowing this to be used to Hold and Turn Small Items in Safety as the Morse Taper is no longer the Prime Retention method.
Holder for Drives, Revolving Centres & Jacobs Chuck
All of the above have one thing in common, they rely on a Morse Taper as their prime means of Fitting into either the Headstock Spindle or Tailstock Barrel of the Lathe.
It is imperative that the Morse Taper (both the Male and Female) are kept Clean, do not get Rusty and remain Un-Damaged, if not then at best the Item will not fit at Worst it will become Jammed into its mating half.
These items, and the many others we have, are often if not always left un-protected and not seen as a potential trouble area, yet the Woodturning News Groups on an almost regular basis have a Thread about yet another Jammed Morse Taper.
The question is always resolved with helpful advise, sympathy and often a suggestion of using Brute Force and Ignorance as the solution. But the question is never asked as to WHY it became stuck in the first place.
The problem is always worse if the offending item has become stuck in the Headstock end of the Lathe and you do not have an Hollow Spindle, and Oh! yes you forgot to replace the Thread Protector when you took the Face Plate or Chuck off.
So cleanliness is the order of the Day and for the Spindle and Barrel Morse Tapers (the Female part) I can recommend the Plastic Morse Cleaners that are now available from most Woodturning Suppliers, they may not be Cheap but they are worth every penny if you never have a Seize Up again.
That leaves the Male Morse Taper on the Centres, Drives and Chucks to maintain in Good Order, my solution was to make a Rack into which the Items in question could be Slotted and therefore protected from Dirt, Rust and Damage.
The Holder supports the various Items with the actual Morse Taper being fully Protected against Rust, Mechanical Damage and Dirt using the simplest of Materials.
The main body is from Aluminum, but Hardboard or Plywood would also be suitable, whilst the inner filling is Water Pipe Insulation (from your local Plumbing Suppliers).
I started with 6 off 75mm (this is suitable for 2MT Morse Tapers for a 1MT then a length of 65mm should be adequate) lengths, this being equal to the longest Morse Taper I had in my collection, of the 15mm Pipe Insulation Tube which is 40mm Ø overall and, providing that no two items are greater than this diameter, you can place them in a line and stick them together with a suitable Contact Adhesive.
This now determined the final dimensions for a 6 way Holder of course if you require more or less then the size will be determined accordingly. Although I had 6 in line you can arrange it how you like i.e. 2 x2, 4 in line, 2x3 etc.
This "Block" of Tubes were now stuck to the Base board which was 260mm long by 50mm wide, I then applied the two sides and the ends sticking them to the Insulation Tube with Contact Adhesive.
This now formed what was a very strong Aluminum Box fitted out with Insulation Tube but I needed to seal all of the joints and I therefore filled the gaps at each corner with Silicone Sealant and placed a fillet of Silicone all around the Bottom Joint sealing the Sides and Ends to the Base.
I now cut a Top Plate into which I drilled 6 off 20mm Ø Holes (for 2MT Morse Tapers for a 1MT Morse you will need a 13mm Ø Hole) at 40mm Pitch to line up with the Centre Holes in each of the Insulation Tubes and then Stuck this in place again using Contact Adhesive.
The Holder is now complete and after a coat of Paint it can be either Screwed, Stuck or Left Freestanding on a convenient Shelf.
Before placing the Items in the Holder I smeared the inside of each Tube with some Light Oil and repeated this three or four times over the next Month, the Oil is absorbed by the Foam Tubes and offers a light Lubrication each time an item is inserted this will ensure that the Morse Tapers remain Rust Free.
of finished Holder / Rack with various Revolving Centres and Drives plus
my Jacobs Type Chuck which I keep under the White Plastic Cover to keep
out the inevitable Wood Dust.
This Cover is a Plastic Bottle type Container with the Top Cut Off it once contained Wood Dye and was the ideal size for the Chuck.
When I remove any Item to use it I replace the vacant Hole with Small Plastic Plug made from a Blind Grommet to ensure no Debris gets in to the vacant place.
One of the most Painful Experiences I have ever had in the Workshop was when I Stabbed my Elbow on the Revolving Center in the Tailstock, this was so Painful I swore I would never have a situation where I could repeat the Experience.
Removing anything from the Tailstock immediately after use is the obvious solution but we are at best Lazy and at worst have a strong belief in our own immortality.
I use 4 different sizes of Live Center plus a Drill Chuck c/w Drill all of which are an Accident waiting to happen when fitted in the Tailstock and not being used, and therefore any solution needed to accommodate all of these variations.
I started with a Plastic Type Cap from a Deodorant Bottle for one size and a Plastic Bottle with the Top Cut off for the second size and this gave me two Protection Caps, these two sizes accommodated the various sizes of Revolving Centers I have.
Into the end of each Cap I fitted a Safety Disc made from 3/8" Plywood, the Plastic alone will not be sufficient to give the degree of protection needed, then using Foam Pipe Insulation glued into the Cap, with a Bore Diameter to suit the Revolving Center, to form a firm grip to hold the Protector onto the Center.
The Protector in place offering full protection against that Oh !*@~! Moment.
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Last update 19 July 2007
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