Thursday, August 20, 2009

HANDLES - SCHELLERT STANDARD HANDLE

THE SCHELLERT STANDARD TOOL HANDLE

While I’ve explained the building process of a simple handle before, personally I like to do my handles in a little bit different way. First I didn’t like to glue my tooltips into the handle, because then they are fixed for ever. If so, I wouldn’t be able to change the tool tip, to give a two sided tool another tool-tip-combination for example. Even the length of the tool tip can’t be adjusted anymore, if you took glue to fix it. So I found another way to do handles in which the tool tips are fixed with a little headless screw. You have to use a small hex-wrench to do this.
It looks like this.



The trick about making this handle is a special kind of adjusting ring that I found via internet (pic 10.). This nice little thing is an adjusting ring made of brass with a socket to fix it into a hole.




You can order this adjusting ring from this German reseller: http://www.schiffsmodellbau-onlineshop.de/ .

I’m not sure if it can be found somewhere else. At least I couldn’t find it elsewhere.

For those who can’t get these adjusting rings, I will explain later, how you can use ordinary adjusting rings and a brass tube as an alternative.

So I started my handle with a piece of wood from the 8mm wooden pole. Because one of these adjusting rings will be added to each side of the handle later, I cut the wood-piece not at 10 cm length, but a little shorter (10cm – 2 x (length of the adjusting ring)), say 9cm this time.

Then I have to drill in the hole into both sides of the handle. As the socket of the adjusting rings has an outer diameter of 4 mm, the hole has to be 4mm wide (pic. 11).



Now the little tool, I’ve talked about before, comes into play. I’ve combined an aluminium tube and a brass tube to form a drilling-aid. With this aid, you can place and keep the drill exactly in the centre point of the tool handle while drilling. So it’s a matter of seconds to make a perfectly placed hole. The pictures below (pic. 12a and 12b) explain how this drilling aid is made.










Obviously, the final hole has to be as deep (or a little deeper to stay flexible) as the tool tip will stuck into it.

But here you've go two options:

The first option is the more simple one. You can see it on the following pic. 12c):




a) take your wooden handle
b) drill in a centred 2.0 or 2.5 cm deep hole with a 4 mm drill.
c) just fix (glue) the adjusting into the hole and fix the tool tip in

Because the hole is now 4mm wide, but the sculpting tools are only 3mm wide, this method leave some "wasted space" (see pic. 12c).
But I don't think, that this is a problem, so personally I make my holes that way.



The second option is a bit more work. You can see it on pic. 12d):



a) take your wooden handle
b) drill in a centred hole, with a 4 mm drill, but only 5.0 - 6.0 mm deep (just as long as the socket of the adjusting ring)
c) fix (glue) the adjusting ring into the hole
d) take a 3 mm drill and drill through the hole of the a-ring into the handle
e) fix the tool tip into the handle

Doing the holes this way makes sure, that the hole inside the handle is only as wide (=3 mm) as needed for taking the tool tips.
It's up to you, which method you would prefer.

If you are in doubt, choose the first option. It's easier to do.


When you got your hole on each side of the handle, just give the handle a good surface with fine abrasive paper and varnish (two layers of varnish are better than one) it as I’ve explained before. Be sure, that the varnish is completely hardened before going on to work with the handle.

So just mount your varnished handle on a skewer or toothpick or something like that and place it somewhere to dry without catching dust (pic. 13).



Now it’s time to modify the adjusting rings a little bit. The inner diameter of the adjusting ring is 3mm. Of course sometimes it’s a little less, so try if you can fit a 3mm tool tip in. If not, just widen the hole carefully with a round needle file (pic. 14).



After that just fix the socket of the adjusting ring into the power drill and set it to rotation (not too fast). Then I took a fine belt sander to bevel or round the upper edge of the adjusting ring. Alternatively to the belt sander you could also use the rotary tool with an insert tool for grinding. I recommend a rougher grinding stone or even better an insert tool with a cylinder like shaped Grinding paper top. Be careful not to grind too much. The hole for the headless screw shouldn’t be damaged. After getting the right shape just smooth the grinded areas and remove all ugly scratches



Do the same thing with another adjustment ring, because you need one for each side of the handle.

All you have to do now is to glue the adjustment rings with their sockets into holes of the handle. Maybe you’ll need to tap slightly with a hammer, for getting the sockets into the holes. But be careful here not to hammer too hard. If it’s too hard to get the socket into the hole, this might indicate, that the socket of the adjusting ring is a little too large in diameter. If you would nevertheless go on beating with the hammer, the stress of the socket to the wooden handle could get too hard and the handle might form cracks or break completely. So take a fine file and file off a little bit from the socket, so it gets a little smaller diameter (don’t widen the hole instead, because a larger hole would weaken the handle). Then try again. Regarding the glue, you should take one that can fix metal to wood (obviously) (pic. 16).


When the glue has hardened, your tool handle is done. As it is now, it will hold 3mm tool tips because the inner diameter of the adjusting ring is 3mm. You just have to place it in and fix it with the headless screw that comes with the adjusting ring and the hex-wrench (pic. 17).



Reducing Pieces:
As the name indicates, my “standard handle” can be used for all tool tips, regardless the diameter of the steel, they are made of. Of course the handle, I’ve explained above is primarily made for 3mm-tool-tips. To fit in tool tips with smaller diameters, I just made “reducing pieces”. That’s nothing more, than little brass tubes with the right diameters and a hole where the headless screw of the adjusting ring can penetrate it.



For 2mm (and 1.5-1.6mm) tool tips, I took a brass tube with an outer diameter of 3mm and an inner diameter of 2mm (material strength: 0.5mm).

For 1mm tool tips, I took a brass tube with an outer diameter of 3mm and an inner diameter of 1mm (material strength: 1mm).

I choose the length of these reducing tubes so that they poke out from the handle a few mm, so you can easily grab them, if you want to change the tool tip size (pic. 19).




To drill in the hole into the sides of the tubes, just fit them into the handle (adjusting ring).

Remove the headless screw from the adjusting ring and mark the point where the hole has to be with a marker by putting it into the hole of the screw. If you pull out the brass tube again, you’ll see the point, where you have to place the drill. Don’t drill through the hole tube, but only to it’s half. The diameter should have the size of the diameter of the headless screw or better a little bit larger. In addition, you should bevel the edges of the drilled hole, so it would be easier for the headless screw to “find” the hole. Clean the drilled hole from all remaining metal particles, so it won’t get stuck into the handle (pic. 20).



Not much more to say about that. Just place the reducing tube with the right diameter into the handle, so that the hole for the handles screw is exactly placed over the hole of the reducing tube, place a tool tip inside the reducing tube and fix it with the headless screw. The screw will fix the tool tip inside the reducing tube while even fixing the reducing tube inside the handle at the same time (pic 21).




One last hint regarding the reducing piece with an inner diameter of 1 mm:

Maybe you’ll find out that the 1 mm tool tips can’t be fixed tight with this reducing piece.
Even you screw it tight it’s just not fixed inside the handle. If this should happen, it is because the point of headless screw is too flat for the small diameter of the brass tube.

So replace the old headless screw with one that has an extra pointed tip like you can see on the following picture. You can find these headless screws in hardware stores and building centres, or just on eBay.







Next time: other variants of the SCHELLERT standard handle

5 comments:

  1. Hi I love this blog thanks for writeing it, I did a little research for a uk site that sells the adjusting rings.
    http://www.cornwallmodelboats.co.uk/acatalog/couplings-modular.html#aC8007
    I hope this is the right bit.

    -Derek

    ReplyDelete
  2. Hi Derek,

    thanks for the information.
    But I'm not sure about the over-all-size of the adjusting ring you've found. I may be wrong, but it looks a little bit too large, no?

    For those who can't find the right adjusting rings, I've developed a method to do the handles without those special adjusting rings with sockets. I will post this tomorrow at about 10:00 AM (German time).

    RingerT

    ReplyDelete
  3. http://www.schiffsmodellbau-onlineshop.de/
    is broken, another links please. im searching but can't find. Thanks you for share

    ReplyDelete
  4. Hi, you can find these special adjusting rings here: http://www.schiffsmodellbau-onlineshop.de/Stellring-Messing-mit-42-mm-Steckmuffe-3-mm-Bohrung_RBM03230_4200#top

    ReplyDelete
  5. Adjusting rings with other sizes can be foud here: http://www.schiffsmodellbau-onlineshop.de/Warengruppe-Material-Werkzeuge-Material-Stellringe-Messing-Stellringe-mit-Steckmuffe_4202#top

    ReplyDelete