HANDLES - simple handle version 2

SIMPLE HANDLES WITH GLUED IN TOOL TIPS - Version 2

Some people prefer tool handles with smaller diameters, especially for very fine tool tips. For those here is a way to make such a handle with brass tubes:

It’s quite the same as the handle I’ve explained before, but instead of using an 8mm wooden pole, you’ll take a brass tube with a smaller diameter. So basically it’s just a brass tube with two smaller brass tubes inside at the ends to reduce the diameter of the tube to that of the sculpting tips diameter.

I guess, for a slim handle a diameter of 4mm would be a good choice (if you want 6mm aluminium might be a better choice than brass because of the weight). You can find brass tubes with different material strength. As I mentioned before, I don’t like if the tools are too heavy, so I recommend using brass tubes with a material strength of 0.5 mm and not the one with 1mm diameter for the handles. The material strength of the smaller “insert” tubes depends on the diameter of the tool tips, you want to place in. Here’s a chart of a useful combination of the tubes diameters:


* Because of the weight use an aluminium tube instead of brass for the outer handle tube

To build such a handle, take a 4mm brass tube with a length of about 10cm.
Then cut two short pieces of the 3mm brass tubes for the “insert”-tube. In most cases a length of 1cm -1.5cm will do (remember: don’t make it too long because of the weight).
After that, just glue the two insert-tubes with the non-bevelled side into each end of the handle-tube (pic. 6a ).

You can also make a handle with 6 mm diameter with a combination of aluminium and brass tubes that have to be glued together like you can see on pic. 6b).

Finally glue in a tooltip in the hole of each insert-tube.

If the surface of the tool tip is too even and you’re afraid, that the glue might not hold it in place, you can roughen the part that has to be glued carefully with a file of the cutting wheel in the rotary tool. Be careful not to damage the tool tip.

That’s it.

Next time: the one and only SCHELLERT standard handle

HANDLES - simple handle version 1

SIMPLE HANDLES WITH GLUED IN TOOL TIPS - Version 1

A very simple handle with glued in tool tips could be made like that:

Take a 10 cm long piece of a wood pole with 8mm diameter for the handle.

I recommend here not to glue the tool tip directly into the wood, but to first glue in a little brass-tube and then to glue the tool tip into the brass tube. By doing this, you’ll give the tool a better steadiness.

Drill in holes for the tool tips on both sides of the wood. The drill should have the diameter of the brass tube. So for example if you want a tool with 2mm sculpting tips, I recommend an brass-tube with an outer diameter of 3mm and an inner diameter of 2mm (material strength: 0,5cm).

You have to be sure, that your 2mm tool tip will fit inside this tube (sometimes they are a little smaller than 2mm). If it is too small, you can widen it carefully with a drill or a needle file.

If you want to have a handle for 1mm tool tips, just use a 3mm brass tube with an inner diameter of 1mm.




A surprisingly difficult part is to drill the hole into the wooden handle exactly centred and straight. Maybe you should drill in a guiding hole with a smaller drill first. I don’t want to talk too much about this point here, but later I will explain a little tool, I build for myself, that helps to drill in such centred holes quite easily.

After drilling the holes in, just bevel or round the two ends of the wooden handle. A quite easy way for doing that is to fix the handle into the power drill. Then while rotating it inside the power drill, grind off the wood with the rotary tool and a grinding tool that is suitable for wood. Keep an eye on the rotating directions of the power drill and the rotary tool to make sure that they didn’t “neutralise” each other (pic. 3).




If you got a nicely bevelled handle, you have to give it a good surface by using fine abrasive paper.

Then you have to glue in the two brass tubes into the holes on each side of the handle. I prefer to let the tubes poke out a few mm (pic. 3a)



Then you should varnish the handle. Be sure to take the right varnish for that. As you will hold the tool in your hand, the varnish should be quite hard. You should ask someone ad the hardware store / building centre, ore wherever you buy your varnish about a varnish, that can be used for that. If you want to do it well, give your handle at least two layers of varnish, first an undercoat / primer and then a second layer of varnish. You can also do the first layer with varnish that you’ve thinned a bit with the right paint thinner. After the first layer of varnish / primer has dried, make sure to abrade / grind it with very fine abrasive paper before doing the second layer. As an alternative to the abrasive paper, you can also use very fine steel wool.

When you work with the varnish, be sure not to clog the hole with it (pic. 4).

After the varnish has dried, all that’s left to do now is to glue in a tool tip on each side. For that you should get a good metal glue (ask at the building centre). A two–part epoxy glue might be adequate here (pic. 5).

The handles on the picture above are not varnished

Next time: a simple handle version 2

HANDLES - general aspects

TOOL TIP HANDLES

Until now, I’ve talked a lot about different kinds of sculpting tool tips and explained the Pencil-Tool and the Schellert-Tool as handles for those tool tips. While the Pencil-Tool and the Schellert-Tool have the advantage that the tooltips can be changed easily and fast, this might sometimes be a disadvantage. After working with your sculpting tools for a while, I am sure you will find your preferred tool tips and you will do 75 % of the sculpting work just with a few of them. In this case, you will surely want to have these preferred tools always at hand, without having to change tool tips permanently.

Therefore, I will explain in this tutorial how to do handles in which the tool tips can be fixed permanently.

Maybe you might think there is not much to talk about. Just take a piece of wood, drill in a hole, glue the tool tip inside the hole and that’s it. You are right. If you are happy with a simple handle, just save your time and just do it like that. I will also explain, how to do such a "simple" handle.

But maybe your have already spent quite a lot of time in forging very fine sculpting tips and you didn’t want to see all your work spoiled by mounting them on crappy handles.
If that’s what you think, I will show you in the following tutorial some ways to do a little bit more sophisticated handles.

GENERAL ASPECTS
Generally, I create nearly all of my handles as two-sided-handles. That’s not a must. You can also do handles with just one tip and this might be indicated with very sharp and / or pointed tool tips to reduce the risk of injury. But in general, I prefer less tools lying around on my work desk while sculpting to keep my workspace clear arranged. So having two-sided tools means half as much tools on your table.

Regarding profile and diameter of the tool handles, I found out, that a rod with a round profile and a diameter of 8mm works best for me. That’s the same diameter as the Schellert-Tool (and these hobby knives like x-acto or martor) has. Beside the fact that I can hold it quite well in my hand it has the advantage, that “8mm” seems to be a kind of standard-size, so it would be easier to find material with that diameter in hardware stores. Alternatively you could use 6mm (also a standard-size), but I recommend that only for small tool tips.

Regarding the length of the handle, I found out, that 10cm (without the tool tips) is a good length for me. If you’ve got the hands of an elf, maybe a shorter one will do better but if your hands are more troll-style even a little bit longer might be adequate.

As material for the handles, there are two good options (for me): wood of aluminium.
Plastic is something, I didn’t really like for my tool handles. Some sculptors also use brass, but a handle with 8mm diameter made of brass could sometimes be a little heavy. So I recommend using brass-tubes only for handles with smaller diameters, like the one, I will explain later.

Wood:
I tried beech-, walnut- and oak-wood for handles by now and all work well (pic. 1). Beech has the advantage that it can be found in poles of 1m length and 8mm diameter in nearly every hardware store or building centre (at least in Germany). Walnut has a beautiful dark brown colour and looks really nice if you give it a finish with clear varnish. Oak has a quite interesting surface structure if you give it a clear varnish and it is quite hard. Unfortunately, 8mm-poles of walnut- or oak-wood are hard to find. In Germany I found this shop: http://www.rundstab.de/ for that. If you are not from Germany, try Google to find the wood you need.

Aluminium:
Aluminium tubes with 8mm and 6mm diameters can be found in most hardware stores or building centres, as I told before (see: “The Schellert-Tool”).
As I already mentioned, there are two qualities available, the untreated “pure” aluminium and the aluminium with the anodized surface. Handles made of untreated aluminium tubes have to be polished finally. A not polished oxidised aluminium surface would leave dark grey marks on your hand. The surface of anodized aluminium on the other hand is just fine, so you can take it as it is without the need to polish or modify it.



Next time: a simple handle version 1

THE SCHELLERT TOOL – the easy way

THE SCHELLERT TOOL – the easy way

In the last tutorial I explained, how to build the original Schellert-Tool.

I can imagine, that some of you would like to have such a tool, but don’t want to do all those thread cutting things. After a search on the internet I found a solution for those of you.

You can make a version of the Schellert-Tool just by using a special kind of pin vice (or pin vise if you are from the US) with only minimal modifications. And that’s how to do it:

First you need the right pin vice and that’s where the magic is. Most pin vices around are not ideal for that job because of the way they are built. Nearly all pin vices work by screwing a nut-like part over a metal-clamp, so that it is pressed together and hold a drill or another tool this way.

This kind of construction results in a tool that is too thick for using it as a handle for sculpting tool tips and the nut-like part is often an obstacle in the hand.

On the following picture you can see such a typical kind of pin vice:

But I found some pin vices that work with a different technique. On these pin vices, there is a clamp with a thread that drags itself inside the handle while screwing it and closing the clamp-jaws this way. In fact, that’s the same technique as found on the hobby-knifes, the original Schellert-Tool is build with.

These pin vices are two-sided and each side can hold tool tips with different sizes.

on the following picture you can see the two different pin vice systems:

For my German speaking audience: The German word for these tools is "Stiftenklöbchen" or "Reibahlenhalter".

I found two different versions of this kind of pin vices, but I guess, there are more out there.
The first (type 1) I got from eBay (it comes from the US) and costs about 3 EUROS.
It could hold 1mm tool tips on one side and up to 2mm tool tips on the other.
This pin vice is a little shorter but with a slightly thicker handle then the other pin vice.

The other pin vice (type 2) I’ve got from a German shop for jeweller tools. This one holds 1mm tools on the one side and up to 3mm tool tips on the other. The pin vice is a little longer than the one from eBay, but the handle is thinner. This one cost about 4.20 EUROS.

type 1:

type 2:


So I recommend getting two of this pin vices (I mean two of the same type; don’t mix the types because the threads could be incompatible) and change one clamp of each pin vice, so you have two pin vices with the same sized clamp on each side. Of course if you want a tool with different clamp sizes on each end, you don’t have to change the clamps.

I found that the screw able part of the pin vice were the finger holds it is too thick for getting a good grip for sculpting, so I replaced it with a 2cm long brass tube with an outer diameter of 8mm and an inner diameter of about 7mm (material strength: 0,5mm). You can find those kinds of brass tubes in hobby- and model craft stores and also in hardware stores and building centres.

I recommend using a tube-cutting tool (see the former post about the Schellert-Tool) for cutting the brass tubes because with it you will always get a clean and straight cut.

Believe it or not, but that’s all. You now have two Schellert-Tools, one for 1mm tool tips and one for 2mm tool tips (or 3mm tooltips - depending on the kind of pin vice you've used).

Maybe the shorter of this pin vices is a bit too short to store the tool tips with 4 cm length, but it’s just a matter of mm. If so, just shorten your tool tips a few mm and they will fit in.

The clear advantage of this Schellert-Tool version is that it’s easy to build, you don’t need complicated tools to build it and it’s quite cheap.

The only downside of this kind of Schellert-Tool is that it is heavier than the original version, because it is made of plated brass (usually) and that the "grip-tubes" are not serrated (not such a good grip). But if you can live with that, that’s your tool.

So I think, I haven’t promised too much. This Schellert-Tool was really the easy way, no?

The basic idea behind the Schellert-Tool is that you can change the tool tips fast. But this is not always a need. In reverse it could be boring, if you have to change the tool tips all the times while sculpting. So maybe soon you want to have at least those tool tips that you permanently work with to be always available at hand without having to change anything.

Because of that I thought about a kind of two sided handles, where the tool tips will be fixed and don’t have to be changed. About this handles I will tell you next time.

THE SCHELLERT TOOL - the hard way, part 2

How to Build the Schellert Tool:

If you have all your material at hand, you can start building the Schellert-Tool.

First you have to cut off a piece with a length of 7cm from the 8mm aluminium tube.
Then cut a slightly shorter piece from the 6mm aluminium tube with a length of about 6.6 cm.

If you want to know, why the second piece have to be shorter than the first one have a closer look on the metal-clamps of the knifes. The clamp is made of two parts, the clamp itself and the serrated little tube around the clamp where the finger will hold the knife (and later your tool). On the bottom side of this tube you’ll discover a very little second tube, which is even smaller. This small tube fits into the 8mm tube, so it holds the clamp exactly in the middle of the aluminium handle. Therefore, the 6mm tube inside the 8mm tube has to be a little shorter to allow some space for this little part from the serrated clamp-tube. So the exact length of the 6mm aluminium tube piece depends on the length of this little part. I saw, that this part has a different length on knifes from the different manufacturers. So if this part on your knifes is shorter, your 6mm tube can be longer. If this part is longer, the 6mm tube has to be shorter. On pic. 7) you might see a little better, what I mean.

If you got your two tubes with the right length you have to clean the cut and remove all scratches from the cut edges on both tubes.

After that, you have to glue the smaller 6mm tube into the larger 8mm tube by using strong glue that is suitable for metal. Be aware to place the 6mm tube in a way that leaves enough space on each side of the 8mm tube to fit the little part from the serrated clamp-tube (see pic. 7b).

Now give the glue some time to get hard. Be sure, that the glue is completely hardened before going on. I recommend waiting for two days before going on.

If the glue is hardened, it’s time to cut the threads into the handle (the two glued tubes). If you never cut a thread before, don’t be afraid of it. I also cut my first threads while building this tool. Just don’t get frustrated, if the first thread might not come out perfectly. Try again.

If you use the clamps with the M5 thread, you have to widen the handle now. If you use the UNC-10-24-threads, just go on with the next step.

So first you have to fix the handle into the bench vice, like you can see in pic. 8). Then drill carefully with the electrical drilling machine and the 4,2mm drill into each side of the handle. You don’t need to widen the inside of the handle over the whole length but just a little longer as needed to take the clamp later. You can hold the clamp beside the handle to see how long the thread of the clamp is and how deep you have to drill.

Before you start drilling, dip the drill a bit into the oil because that will reduce the chance of the drill getting stuck into the handle. Don’t rotate the drill too fast but even not to slow. Be very careful with that and make sure, that the handle doesn’t rotate with the drill in the bench vice because that would result in very ugly scratches on your handle.

Now you can start cutting the threads. Just fix the handle in the bench vice so it points upwards like in pic. 9. Be sure to use some kind of protection bars (braces) on the bench vice to prevent scratching and damaging the handle. Be sure that it sits as tightly as possible without damaging the tubes. Then dip the thread cutter a little bit into the oil. Don’t "oil" too much. A thin skin of oil is enough. And make sure not to drop the oil onto the vice where it holds the handle or you won’t get a tight grip anymore and the handle could start to rotate.

If you use the 3-piece thread cutter set, you have to start with the thread cutter (threader) that is marked with one line.

Place the thread cutter into the hole of the handle and slowly start rotating it in clockwise direction. You need nearly no pressure here, just rotating. Be sure –and that is MOST IMPORTANT- that you hold the thread cutter 100% straight and not in an angle to the handles hole. If you don’t work precisely here, your thread cutter might stuck after a few mm and later the clamp will not sit straight into the handle and that would be a mess. So work slowly and precise and control the position and the direction of the thread cutter all the time.

Even you need some power to drill (rotate) the thread cutter in, be careful not to turn it with too much power. If the thread cutter seems to get stuck or if it gets suddenly harder to turn, it might indicate that you didn’t hold the thread cutter perfectly straight, so control its position. But it can also indicate, that the little metal parts, that you’ve cut off with the thread cutter are getting too much inside the tube and blocking the thread cutter now a little bit. In this case stop turning the thread cutter and rotate it back in counter clockwise direction for a half or a full turn. When you do so, you might first notice a little resistance when you try to turn the cutter in counter clockwise direction. That’s normal and nothing to worry about, so try to turn it a little bit harder, but always keep in mind to control the power you use. Brutality is not an option here.
You will see that if you get the right point, suddenly the thread cutter will move as you want and you will also feel in your fingers, that some kind of obstacle has passed.

So after you’ve rotated the thread cutter back (counter clockwise) for a half or a full turn, and there’s no obstacle anymore, just try again to go on with cutting the thread by now turning the thread cutter in clockwise direction again. In most cases now you can go on without getting stuck. If you’re getting stuck again, repeat the procedure.

But sometimes even the "half-turn-back-trick" didn’t work right and you still get stuck at the same position. If this happens, don’t try to go on rotating too hard or it could happen, that the handle starts to rotate into the vice and that would result in ugly scratches on the handle. When getting stuck, remove the thread cutter completely from the handle by turning it into counter clockwise direction (not only a half turn, but get it completely out of the handle this time). You will see then a lot of little aluminium pieces stick to the thread cutter because of the oil. "Clean" the thread cutter by removing all those little metal pieces. You can for example use an old toothbrush or a stiff-bristled brush for that. After removing all these aluminium parts dip the thread cutter once again into the oil and try again to go on with cutting the tread, where you’ve stopped before.

When you place the thread cutter into the handle again, be sure, that it finds exactly the thread that you’ve already cut. Otherwise you would start a second thread right from the start "beside" the already cut thread and that would make the whole thing useless. Just turn the thread cutter slowly into the hole of the handle with no pressure like it would be bolt and nut and the thread cutter will find its way. Now you should be able to go on with the cutting.

The problem with this "getting stuck" appears more often with the single-turn-thread-cutter. If you use this, I recommend not to try doing the whole thread in one turn, but to stop at say halftime and to clean the thread cutter like explained above. With the 3-part-thread-cutting-set you have to face this problem less often.

Go on with cutting the thread until the thread is long (deep) enough. How long it has to be depends on the thread of the knife clamp you use, so hold this part beside your handle to see how deep the thread has to be. To be sure, you should make it a few mm deeper than needed.

If you use the single-turn-thread-cutter, you’re done now with this side and you can go on cutting the thread into the other hole of the handle. If you use the 3-part-tread-cutting-set, you have to repeat the procedure with the second cutter, that’s the one marked with two lines and finally with the third cutter, that’s the one marked with no lines.

The procedure for the other hole of the handle is exactly the same as described above. Just be sure, to avoid getting oil on the safety bars (braces) of the bench vice or on the handle, because that would extremely reduce the bench vices ability to hold the handle tight.

If you got your threads done and if they hold the clamps perfectly straight (try it now), you’re nearly done. You should clean the handle and especially the inside of it to remove all the left aluminium particles and of course all the oil. This is important, because otherwise the remaining oil will get hard, starts to smell (when you use the sunflower oil) and might "glue" the clamps in your tool. To clean it use a lot of water in combination with liquid dishwashing soap (fluid) and those cotton sticks usually used to clean the ears.

If you have done all that, and if you have fixed your clamps to each side of the handle…
Ta dah… your very own Schellert tool is done.

Ah, sorry one thing left: If you used the pure aluminium tubes and not the anodized ones, you have to give your handle a good surface. Just remove all those scratches with abrasive paper and polish the handle after that. To polish the pure aluminium isn’t only to achieve a better look, but also to prevent those dark grey stains, that you would find on your hand, if you work with unpolished aluminium.

Now you have to fit your 1mm tool tips into the clamps of the Schellert tool.
Any of those clamps from hobby knifes I saw were able to hold 1mm tool tips without any modification. If this would not be the case for the knife clamps you’ve used and if the space between the "clamp jaws" might be too thin to fit a 1mm tool tip into its cross section, you can widen this cross section by carefully drill in with a 1mm drill. If you have to do this, remove the serrated clamp tube before drilling. Otherwise this little tube might press the "clamp jaws" together while drilling and that would result in a drilled hole, that’s much larger than the 1mm you want.

If you unscrew one of the clamps, you can place the 1mm tool tips inside the handle and store it there. There should be enough space to store 6-7 tool tips, maybe more.

And one more thing: Most of these knifes come with those safety caps, like you can see on pic. 11). Don’t throw these caps away, because they are ideal to protect your tool tips if you didn’t want to store them inside the handle.

THE SCHELLERT TOOL FOR 1,5MM AND 2,0MM TOOL TIPS

The "original" Schellert Tool was made for 1mm tool tips, but it is very easy to build a version for larger tool tips like those made from 1,5mm or 2,0mm Steel wire. All you have to do is to widen the cross section of the cuts in the clamps with the right drill.

For the knife clamp that I use, I found out that a clamp, that I widened with a 2mm drill will not only hold 2mm tips, but also 1.5mm or 1.6mm tips perfectly.
Remember to remove the small serrated clamp tube before drilling.

THE SCHELLERT TOOL FOR 3MM TOOL TIPS
To say it right from the start: I don’t recommend to just widening up the cross sections of the clamps to 3mm as I described above for 1,5mm and 2mm. The reason is that this would make the clamp itself too thin and it might break. So the usual clamps from those hobby knifes I always talk about in this tutorial are not ideal to make a 3mm tool tip holder from.
But there is a solution. If you search a little bit, you’ll find another version of that hobby-knifes. These special versions not only have a cross cut on the clamps to hold the blade, but a real cut-out hole, where you also can fit in tool tips with a round diameter. Have a look on pic. 13) to see what I mean.

I found this kind of hobby-knife from the German manufacturers MARTOR and ECOBRA, but if I’m not completely wrong, even X-ACTO produce such a knife. The knife made by MARTOR (it’s called "grafix" by the way) has a clamp, that could hold tools made from 3mm steel wire. I’m not sure about the other manufacturers, so you have to look for yourself. Unfortunately these knifes are more expensive than the usual hobby knifes.

With those special clamps you can build a Schellert-Tool for 3mm tool tips. There are just some differences in building it. Most important is that these knife clamps have a different thread size. The MARTOR Grafix-knife has a 6mm M6-thread. I don’t know the thread-sizes from the other manufacturers.

Because of this larger thread size, you’ll need a handle with an outer diameter of 8mm and an inner diameter of 5mm, as the base-hole for cutting an m6 thread is 5mm.

So here you can’t do the trick with the two aluminium tubes glued together, because the m6-thread is 6mm wide, so the smaller aluminium tube with the 6mm diameter would be too small to cut an m6-thread in.

So what you need here is a single aluminium tube with an outer diameter of 8mm and an inner diameter of 5mm (material strength: 1,5mm). Unfortunately it’s not easy to find aluminium tubes with that size. At least it took me quite a lot of time googleing around until I found someone here in Germany who sells it. Maybe it’s easier in the country where you live.

If you can’t find this size of aluminium tubes but you desperately want a Schellert-Tool for 3mm tool tips, there’s one other thing, you can do:

You can cut off the handle of that special knife at the backside, so the handle is about 6-7cm long. I mean the opposite part of the side that holds the clamp. What you have to do then is to drill a 5mm wide hole into the cut side of the handle. The problem is that this hole has to be placed exactly in the centre point. This isn’t quite easy to achieve.

So first you have to find exact position of the centre point first. There’s a trick you can: Place the handle into an electrical drilling machine (power drill) and let it rotate (not too fast). Then touch slightly the cut end of the handle with a pointed pencil. When the lead of the pencil leaves a circle, you are not in the middle, when it leaves just a point you are exactly in the middle (centre point). This point marks your centre point now and this is where you have to drill in.

Take a thin drill (like 1mm or 2mm) now and drill a "guiding hole" exactly in the centre point. After that you can try to drill in the 5mm hole and hope, that the "guiding-hole" keeps your 5mm drill exactly in the centre. I tried this several times and sometimes it went fine and sometimes it did not. Maybe you know a professional metal worker, who has machines to do this kind of work more precisely.

When you succeed in getting the hole in, you just have to cut the m6-thread.
The good thing is that you only have to cut one thread, because the other is already there. Of course the handle of this tool isn’t hollowed, so you can’t store the tool tips in.
But this isn’t a problem, because this tool-version is for 3mm tool tips and those are too big anyway to fit into that handle even if it would be hollowed (except for a straight needle maybe).
On the following picture you can see all three sizes of the Schellert tool

So that’s all about the Schellert-Tool. I hope you’ll like this tool.

Next time I tell you about an "easy way" to build a tool that is quite similar to the original Schellert-tool.

THE SCHELLERT TOOL - the hard way, part 1

THE SCHELLERT-TOOL –the hard way -part 1-

Welcome back. Today I want to show you how to build the "Schellert-Tool". The Schellert-Tool is basically nothing more than a small tube with a metal-clamp-system on each side, where you can fit sculpting tool tips in. The tooltips could be stored inside the hollow tube (pic. 1). This tool has some advantages over the pencil tool because it is a two-sided tool and the sculpting tips are fixed more tightly in it, so they won’t rotate. You can make versions of this tool for all steel wire diameters (more about that later). I called this tool "Schellert Tool" because I didn’t found another name. "The-two-sided-sculpting-tool-with-exchangeable-tool-tips" was a little bit long for my taste. So I gave it my last name, that’s all.

If you ask yourself why I wrote in the title of this post "the hard way", it’s because you have to do a little metal working like cutting threads for example. There is also an "easy way" to get a kind of a Schellert Tool which is nearly as good as the original one with a minimum of work. I’ll tell you in a later tutorial how to do this.

The basic idea behind the Schellert tool is to grab two of those hobby knifes (like x-acto, excel, proedge, martor or ecobra to name a few), get the clamps from these knifes where usually the blade is placed in and fix them on each side of a small aluminium tube by cutting threads into the tube. Of course you can just use the hobby knife as it is and fix a tool tip instead of a blade in it, but that’s only a one-sided tool, you can’t store the tips inside the handle and hey, it’s not so cool.

Material and tools needed:

Two hobby-knifes (pic. 2):
First you need two hobby knifes to get the clamps. Here’s where the "trouble" begins.
These knifes are produced in different countries and therefore the threads of the clamps of these knifes are different. The knifes from Germany like those from Martor and Ecobra are using a metrical thread-system. In fact they have an "M5"-thread. The knifes from Excel and I guess even the knifes from x-acto and proedge (I guess they are from the US) using another thread-system. They have a UNC 10-24 thread. You have to know which thread your knifes have because you need the right thread-cutter (threader) for cutting the thread. I recommend using 2 knifes from the same manufacturer.

Regarding these knifes it is worth to look a little bit around for the prices, as there are great differences even for knifes from the same manufacturer. So for the ECOBRA-knife for example I found the range from 2.10 EURO to 9.90 EURO and it was always the same kind of knife. So google until you find an acceptable price. As far as I can see (here from Germany), the prices for those knifes (especially EXCEL and PROEDGE) are a little bit lower in the US, so lucky you, if you live there.

Thread cutter and holder (pic. 3):
As I said before, you need a thread cutter (threader) with the right size. Depending on the knifes you use you’ll need either a thread cutter for M5-threads (German) or one for UNC 10-24-threads (US).

You have to take those thread-cutters for cutting threads by hand, not those for machine-thread-cutting.

There are two types of hand-thread cutters around. The first exist of only one drill-like tool, and you can cut the complete thread in just one turn with it.

Then there is also a set available that exists of three drills- like tools. One for pre-cut (marked with one line), one for the second cut (marked with two lines / cuts a little deeper) and the last one for the final cut (marked with no lines / complete thread).

If you have the choice, take the 3-piece-set. It’s a bit more work because you have to cut three times instead of only one time, but cutting is easier with the set because you’ll need less power. And because the forces that work on the tube while being cut aren’t as high, it’s not so likely, that the tube will rotate in the bench vice while cutting the thread.

And of course you’ll need a holder for your thread cutter like you can see in pic. 3.

Aluminium tubes (pic. 4):
You need two aluminium tubes like those you can found in hardware stores or building centres were you can buy them in 1m or 2m length. The 1m size is more than enough.

You’ll need

- one with an outer diameter of 8mm and an inner diameter of 6mm and
- one with an outer diameter of 6mm and an inner diameter of 4 mm.

The strength of the tube walls is 1mm on both tubes (just to make it clear).

There are two kinds of aluminium tubes that can be found, those with a pure aluminium surface and those with an anodized surface. In hardware stores or building centres (in Germany) most of the times the anodized ones can be found. You can use both versions. The anodized ones have the advantage, that the surface of the tubes has already a finish, so it’s less work later. The "pure" aluminium ones have to be grinded and polished to remove scratches, but this will result in a very beautiful shiny surface.

But one thing is very important about these tubes. The smaller 6mm one should fit easily into the larger 8mm one! That’s not always the case, because those tubes have never exactly the sizes, they claim to have. So before you buy the tubes find a pair that will work. I mean you need a quite large 8mm tube and quite small 6mm one. Try every 8mm tube with every 6mm tube until you find a 6mm one that fits into the 8mm one. If you don’t do that you’ll get into trouble because you have to widen the 8mm tube later, so the 6mm will fit in. And believe me, this is something, you didn’t really want to do if it can be avoided, because it’s really a mess (you shouldn’t make my mistakes).

Bench vice with protection bars (Braces) (pic. 5)
You’ll need a bench vice, where you can fix the aluminium tube in while cutting the threads.
To protect the surface of the aluminium tube, you need some kind of protection bars (braces).
The one you see on pic. 5 I made on my own from strong felt.

Fine metal saw or tube-cutter (pic. 6)
You have to cut off pieces from the aluminium tubes. To do so you will need a fine metal saw or even better a tube cutter or pipe cutter (see pic. 6). The tube-cutter is a very fine tool and not even is cutting much easier with it; you’ll always get a clean 90-degree cut from the tube. So when using the tube cutter you’ll have less work to do to clean up the cut.

Electrical drilling machine (power drill) and 4,2mm metal drill:
If you use the knife-clamps with the M5-thread, you will also need an electrical drilling machine and a drill with the size of 4,2mm. This must be a drill for metal (not for wood) of course. You’ll need this drill to widen the inner diameter of the small aluminium tube from 4.0mm to 4.2mm because for cutting a M5-thread you need a base hole of 4.2 mm.
If you use the other knife clamps with the UNC 10-24-Thread, you are lucky, because for this thread-size a base hole of 4,0mm is fine and that’s the diameter, the small aluminium tube already have. So no need for a special metal drill or the electrical drilling machine in this case.
　
Good glue for metal:
You’ll also need good glue for metal. It’s not important, that it is fast, but it is important, that it is really hard and strong in the end. I recommend those two-part epoxy glues.

Abrasive paper:
You’ll also need some fine coarse grinding paper to clean the cuts on the tubes.

Oil:
When you cut the threads into the aluminium tube, you need to dip the tube cutter in oil before. Otherwise cutting is much harder and the tool might get stuck into the tube, so ALWAYS use oil when cutting threads. When I did the first thread cuttings, I just used ordinary sunflower oil that is used in the kitchen. Later I bought an expensive special super metal drilling and cutting oil. But believe me or not, I found the sunflower oil works better, so I’m now back to that. Maybe some metal-working-professionals will get a heart attack now, but that’s what I found out for me. So there’s no need for you to buy special cutting oil. Just try what you’ll find in your kitchen (and don’t tell your wife).

POLISHING SCULPTING TOOL TIPS

As I promised before, today I will explain how to polish your sculpting tool tips. Because polishing isn’t such a complicated thing, I won’t make many words about it; just some hints.

Before polishing, make sure, that you’ve cleaned up the surface of the tool the best you can, by removing all scratches with fine abrasive paper. Fine scratches can be polished away, but deeper ones have to be removed with the abrasive paper. Even better than abrasive paper are abrasive pads.

For the polishing you need some kind of polishing tool (pic 1).

If you really want to do a lot of tool tips, maybe you should get a cheap polishing machine. That’s a machine similar to the grinding-machine that I’ve talked about before, but just with two felt-wheels instead of the grinding stones. If you already own such a grinding machine, it’s most likely, that you can buy separate felt-wheels to replace the grinding stones on your machine. That would be cheaper than buying a second machine.

But if you just want to make a few tool tips for yourself, you won’t need that.
If you got a rotary tool, you can find small polishing wheels to fit into it that makes the job quite well and they aren’t very expensive.

If you haven’t got a rotary tool (Dremel or Proxxon or something like that), you can also find such a polishing wheel made of felt to fit in an ordinary electrical drilling machine (power drill), that can be found in most houses.

I prefer the polishing machine or the rotary tool over the drilling machine because of the higher rotation speed (and the lesser noise they produce).

Second you need some kind of Polishing Agent. For the small rotary tools, it is usually available in small plastic boxes. For polishing with the larger polishing machine, they are also available in form of a bar, like you can see on pic.1. If there are different types of those polishing agents in the shop and you are unsure which one to take, ask someone from the store which is the best for polishing steel.

All the tools and the polishing agent can be found at hardware stores or building centres.

If you got your polishing tool, let it rotate.
Then first press the polishing agent slightly onto the rotating wheel, so the felt can take up some of it.

Now take your tool tip and slightly press it onto the polishing wheel (pic. 2). Be sure, the tool tip point into the same direction as the rotation of the wheel. If you have problems to hold the small sculpting tool tip in your hand without letting it fly around, you can fix it in some kind of pin vice to get a better handle.

Soon you will see that the polishing agent gets fluid and turns into a dark grey colour because of the steel particles that were polished off. That’s good because it means that it works.

Once again, wear safety glasses and NOT your best shirt while polishing, because this black fluid drops (and sometimes even the tool tip) tends to fly around.

Check your progress from time to time, by whipping off the black fluid from the tool tip with a tissue or some fabric to see the surface under it. If the surface is perfectly shiny and no scratches can be seen anymore, your tool tip is done and you can start polishing the next one.

That’s all about polishing from my side.