Tools for the job: Tag removal

[Kenton]

So I use the following tools working from the right depending on the size of the part, tag and scale I am working in.

 

 

scissor snips: only of use for where the part is well separated from the waste fret, has a tendency to twist the tag.

snip/zircon pliers: a clean cut but also limited by the gap between part and fret, not good for small parts and squashes big tags.

sharp scalpel with pointed blade: used with either a cutting mat or preferably a hardwood block. good for all but the smallest of parts but blade blunt very quickly.

piercing saw: main problem is access to a part within a fret and having to remove/replace blades.

 

Over to everyone else ... what do you use to cut parts from frets.

 

especially ones like these?

and this is what I would consider a well designed fret only one tag for such a small item. But I will not be using that blade to cut that tag.

[sjp23480]

An old slimline chisel (sharpened with my Dremel) and piece of steel (the more substantial part of an engineers square) to put the etch on whilst applying pressure with the chisel.

 

Seems to detach most things from the etch without any distortion.

 

steve

[Pugsley]

I use a sharp Stanley knife almost exclusively, but use scissors if the access is good enough. The Stanley blades blunt eventually, but they're cheap enough.

 

It doesn't seem to have adversely affected the scissors either.

[hollywoodfoundry]

You hinted at something I find a pain, too many tags holding parts into the fret. Many designers are prone to using too many tags, and if they are opposite each other, you end up distorting the part when removing them. If you use too few parts, the etching company will hate you because the parts twist in the bath and fall out of the fret.

 

The other thing is to place tags where they won't be seen on the finished model if possible and also to place then where it is easy to clean up the residual tage once the part is removed from the fret.

 

I use a combination of scissors and a large Stanley knife to do the job. I find the scissors work well when the parts are opposite each other, as the action shears the tag rather than compressing it and distorting the part.

[coachmann]

I'm a tag minimalist!............. Important when building ones own produced models to a timeline. Tag positions are always carefully thought out. I generally place one top & bottom diagonally opposed on small items so they wont distort the item when being clipped out of the fret. (buffer beams etc).

 

I remove etched parts with Xuron clippers, but a Swann-Morten knife also has its uses.

 

Larry G.

[hollywoodfoundry]

Me too, and I am always getting into trouble with my etching company because of it. They do not realise that it is OK for a modeller to spend some time cutting out lots of tags when they are making one model.

 

But I buy 10 or 15 sheets of components at a time and my wife helps by cutting the components out of the fret. To make it easier on her, I made less and thinner tags.

[coachmann]

Hi Hollywood,

 

I think one of the problems in etching is people looking at what exists and copying old ideas instead of looking at things afresh. Of course if they have no previous experience then bad ideas will end up being duplicated for evermore.

 

Few kits are 'commercial' (they take too long to put together) and one really needs to re-think everything when etching parts for ones self, as no doubt you have done.

 

Cheers,

Larry G.

 

 

[Kenton]

Specifically on the subject of tag size and position (rather than how to cut them), I can understand the compromise that has to be achieved between a part being held on the fret and it falling off into the etching bath. But what I don't understand is the apparent lack of thought that goes into the positioning of the tags and quite often the actual size of them.

 

Of about 6 different kits in front of me they range from what appears in the photo above, to those that have had no thought and some are not even half-etched, some where guessing where the part ends and the tag starts is impossible, through to those where the tags are both long and very fine - more like a thin wire.

 

In general the best kits are undoubtedly where they have been designed using CAD this seems to enable thinner lines and this is also reflected in parts that fit. Even so to the avid constructor it is still possible to spot some that may have looked good to stat with but when it comes to removing them it is obvious a different view should have been taken.

 

As to the number of tags - well I suppose from a constructors point of view one is too many though the use of 13 on one large but narrow part is far too many.

 

I think also there is perhaps a understandable tendency to rush out a new kit (we kit builders don't help by champing at the bit for every new release) this means something that is really a beta test etch sees production with what are only trivial faults. If the kit sells well, then as by using CAD it is so easy to correct such things one hopes that the kit designer takes on feedback and makes some of the minor changes. Sadly in many cases this is unlikely to happen as many of the kits seem to have vanished from production or simply do not sell in the numbers required to sustain multiple runs or changes to the masters.

[Wizard of the Moor]

what do you use to cut parts from frets.

 

A Stanley knife with a curved blade - straight ones break very easily - working on an offcut of laminate flooring. The curved blade allows a rocking motion during the cut which makes it easier to get close to those fine parts without distortion.

 

My pet hate is tabs located at the ends of long components that are contained in matching rebates in the fret. Brake levers and coupling rods seem to be very prone to this. It is often impossible to cut these tags with a knife or cutters. A piercing saw is the best option in such cases.

 

Cheers,

 

James

[hollywoodfoundry]

Hi Hollywood,

 

I think one of the problems in etching is people looking at what exists and copying old ideas instead of looking at things afresh. Of course if they have no previous experience then bad ideas will end up being duplicated for evermore.

 

Few kits are 'commercial' (they take too long to put together) and one really needs to re-think everything when etching parts for ones self, as no doubt you have done.

 

Cheers,

Larry G.

 

I agree that not enough thought goes into etches. And I think you are spot on that a lot of it is due to simply copying old ideas.

 

Specifically on the subject of tag size and position (rather than how to cut them, I can understand the compromise that has to be achieved between a prt being held on the fret and it falling off into the etching bath. But what I don't understand is the apparent lack of thought that goes into the positioning of the tags and quite often the actual size of them.

 

Of about 6 different kits in front of me they range from what appears to those that have had no thought and some are not even half-etched, some where guessing where the part ends and the tag starts is impossible, though to those where the tags are bothe long and very fine - more like a thin wire.

 

Again, very true. However sometimes the component is so tiny, the tags are just extensions of it. The photo shows a quite small etching in 0.125mm phosphor bronze. The components comprise mostly the lubricator piping for an Australian steam locomotive. This is a very small etch, it is barely one inch wide., and the smallest pipes are only 0.125mm wide.

 

You can also see the part numbering scheme I use. Each part is number, placed in a circle and has an arrow pointing to the part. Some items also show the quantity of items contained, for example part number 162 has 30 copies.

 

I have a set of rules for etching:

 

1. Place all parts of the same type in the one place on the fret, do not scatter them around the fret to save space.

2. Number all parts, indicate the quantity if more than one, and point to them with an arrow.

3. Add extra parts for the tiny ones that go 'ping' and vanish.

4. Use the thinnest tags you can get away with and the least number.

5. If possible, taper the tag towards the part.

6. Always half etch tags.

7. Place tags where they will not distort the part when cutting, and also where they can be cleaned off easily.

 

Geoff

[Kenton]

Useful rules. But I would reverse them in order of priority. In some cases just following the basics of quantity, position, and size would help kitbuilders. Extra duplicate parts are a great help - carpets are like brass magnets. But I don't mind scatter over the etch as long as the parts can be identified - it saves on brass and therefore cost. Oh, and use nickel silver for hard wearing parts such has crank shafts. Don't forget that laminating half-etched detail is easier for the kitbuilder than adding a small part in true alignment.

[coachmann]

I agree nickel silver has its properties such as when something hard-wearing is required, or the part would remain unpainted to represent steel. For example, if I were ever to produce Bullied or BR Mk. I coaches the sides would be in nickel silver both for strength and the fact that door handles & grabs are 'chrome'.

 

My earliest LMS solebars were etched in nickel silver but it was an expensive excercise when brass would have sufficed. On the 'up' side, I also had some very fine emergency-chord parts etched that the etcher phoned to tell me would simply dissapear in the acid bath. To everyones suprise they were perfect and looked for all the world like nickel silver wire! But we were back to the vexed holding-tabs, which still tend to bend the items when being removed from the fret.

 

LG

[hollywoodfoundry]

For really hard wearing parts, etching in stainless steel is an option. I used it to good effect when producing a third rail skate for an old style American 3 rail model in O gauge.

 

It works extremely well, and is also great for the large grilles on the sides and tops of diesel locomotives, as it is far more resistant to dings and such. One problem though is that you need to glue it in place, as it is extremely difficult to solder to other metals. Another are those damn tags again, this time they are really hard to cut in stainless. Good design of tags becomes essential in stainless.

[Kenton]

as it is extremely difficult to solder to other metals.

with the right flux (Carrs's green) I appear to have little problem soldering steel nuts to brass - especially accidentally - though not tried "stainless" which may be a totally different kettle

[Bruciethefish]

I tend to use ordinary scissors for most parts, flexing the fret between my fingers to improve access, & cutting away scrap areas where it's easier.. I also use a score & snap technique, - run a sharp scalpel blade across the tag, right next to the component to induce a weak point, then bend the component away from the fret;- the score will produce a stress point which will easily fracture, releasing the part. This can be useful where a lot of tags are present in a parrallel line.....

[craigwelsh]

Here's an example of a couple of tabs I cocked up on for a test etch. The top 4 were parallel and possibly a few too many while the bottom one made it to the production etch annoyingly as its next to a tab you want to keep. Bit of a cock-up that one but you live and learn.. In your OP example I would have put much smaller tabs on opposite sides diagonally although on my own etch the spring carriers are down to 0.35mm tabs on a 0.25mm sheet of nickel and you can push the piece out, a bit thin those! On the main chassis i'd probably put less tabs too now but sometimes the retained bits give the rest of the fret a bit of rigidity back as I do like to get my monies worth!

 

I use a small Swann Morton blade to remove all of the tabs on things im building pressing either on some conti board or on very thick card on top of the worktop. I don't use a cutting mat for this as I find them too soft and liable to deform the part. I tend to slice the tab a couple of times softly rather than apply a lot of pressure to avoid snapping off the very fine tip of the blade.

[Jol Wilkinson]

Quite a few years ago I was given a small selection of handmade tools by John Hayes, who is probably one of the best 4mm loco builders and whose work regularly appeared in MRJ.

 

These included a tab chisel, made from a hacksaw blade. I've included a photo, which I hope is satisfactory. The chisel is made by grinding a 2 -2 1/2" piece from the end of a good quality hacksaw blade to a tapered end about 2.5 - 3 mm wide. The end is then ground off at 30 degrees on one side, just like a wood chisel. These are the red and yellow tools, although the red one (which I made later) is a bit too short to hold comfortably.

 

By placing the point of the chisel on the tab, with the flat side against the edge of the part being removed, and then applying a gentle whack with a 2oz hammer, the tab is cut through cleanly, leaving a minimal amount to be filed off. Using a small chisel like this means you can cut tabs out on the inside of curves and other awkward places. I use a piece of Formica (not Melamine) face chipboard as a work surface, this supports the etch to avoid distortion but doesn't blunt the chisel point. It is important to have the rounded end of the hacksaw blade as the "striking " end as this is apparently less hardened and brittle than the rest of the blade.

 

I haven't used anything else for cutting through tabs for about 20 years and find it better than any other method, so I have included a drawing of the chisel in the instructions of the etched kits I have designed for London Road Models.

 

John also gave me a set of "solder" scrapers, made in a similar way. These are the blue tools in the photos. There are two types, left and right "handed" and are superb for removing excess solder from corners, etc.

 

Jol

[ArthurK]

The only weapon I use is a Swan Morton cutter with the blade ground to a chisel edge from both sides (about 30 degrees angle) . It is advisable to grind off the cutting edge at the same time, saves fingers!

If the tag is half etched push the blade up to the part from which you are removing the tag, press down bringing to tool to near vertical as you do. The tag was be removed completely without distorting the part, however fragile. If the tag is the same thickness as the part the align the edge as near as you can. The table surface must be hard so that it cannot distort. I use an aluminium sheet but steel is better.

 

The tool is easily resharpened either with a grinding wheel or fine wet&dry paper.

 

This method works very well in 4mm scale for brass upto about 15thou and Nickel Silver up to 20thou.

 

Sorry about the quality of the picture, it was scanned rather than photographed.

[craigwelsh]

Interesting chisel tools, I must admit I just use one of that type Swan Morton with the blade 'as is' in knife mode. Its worked alright on these bits which are a lot smaller than the knife http://www.rmweb.co.uk/community/index.php/blog/64/entry-1065-making-a-lever-guard/ !