7mm On Heather's Workbench - Prairie ago-go

Scale7JB

Western Thunderer
View attachment 117529

Baby steps. I set myself the task of permanently attaching the bearings and fitting the frame overlays. I remembered to trap the compensation beam before attaching the overlays! Some very slight binding with the coupling rods on, but I haven’t sorted out sideplay yet so that is to be expected.

Happy with that. I suppose making up the cylinders and seeing if the gearbox fits will be next.

Hi Heather, I hate to say it, I think lack of side play on a tight curve would cause a continual resistance rather than a bind. Can you try on a piece of straight track before moving forward with cylinders etc?

JB.
 

Heather Kay

Western Thunderer
Hi Heather, I hate to say it, I think lack of side play on a tight curve would cause a continual resistance rather than a bind. Can you try on a piece of straight track before moving forward with cylinders etc?

JB.

I used "binding" as a coverall term. You are more correct. What I meant was at this stage, without limiting the sideways movement of the wheels, all kinds of stickiness is apparent, but none of it a cause for concern. When I get the rest of the motion organised, I can decide on clearances and sticking washers in to stop things being too sloppy.

Meanwhile…

8B1B08E2-53EA-4E68-8DD4-8246C45B20E1.jpeg

Everything just dry fitted to check things will work, but I’m happy with the etched slidebars. I’ve even got some little cast oil pots to go in on the top ones eventually. I really didn’t fancy attempting to fabricate the crossheads from the etch: one might get away with such things in 4mm scale.

1424609F-E02B-4ADF-A24A-8900C978B4D9.jpeg

As with the previous Prairie, I couldn’t use the NS etch cylinder wrappers as they’re just too thick to form sensibly. It only took 15 minutes to knock up new wrappers from thinner NS sheet, and here they are cooling down after being annealed a bit.

Getting there. Once these tedious jobs are out of the way, it should start to get more interesting. :D
 

jonte

Western Thunderer
Hi Heather

I’ve always wondered how you remove individual pieces from a fret.

For instance, do you use a sharp Stanley blade on a hard surface so’s not to distort the part, or perhaps a piercing saw on a custom made ‘bench’ of some sort, or even tin-snips/Xuron type cutters?

Intrigued of Merseyside. :)
 

Heather Kay

Western Thunderer
Intrigued of Merseyside. :)

Dear Intrigued of Merseyside,

It depends on the part. Fine brass parts, densely packed on the fret and on thin material, can be parted using a sharp Swann Morton No10 rounded blade. Thicker material needs tougher methods. My usual method is to use a pair of Fiskars needlework scissors to snip the tags to free the part, and then to trim close to the part to eliminate as much filing as possible. I also have a pair of tin snips for when the Fiskars aren’t up to the job. Actually, it’s my fingers and thumbs in that case, as I can’t get the leverage.

I’ll do some photos later today to show how I do it.
 

simond

Western Thunderer
Jonte,

Speaking personally, all of the above, though not very often with the piercing saw. They’d have to be thick etchings, but a saw is sometimes the only way to get a casting off a sprue.

The ideal fret is designed so that you can use a “right handed” pair of shears (eg, Xuron) with one blade against the half etched edge above the tag, and the other can then cut flush, which cuts down the filing of tags to a minimum.

The least ideal fret has tags on concave edges of fragile parts. You can’t snip, and cleaning up distorts the part. :(

Others’ mileage might vary, of course.

Atb
Simon
 

simond

Western Thunderer
Yep scissors,

well-used Xuron, but I do use others more like those that Dave has linked.

image.jpg

And “ a good tag”.

image.jpg

The upper blade is against the etched edge, and the lower, which has an “overbite” is below the tag. Snipping here leaves an almost perfectly tag-free edge.

OTOH, these are a PITA to clean up, particularly the tags on the inside of the curve which you can only get at by filing across the thickness of the etch, or with a rotary tool

image.jpg

Atb
Simon
 

LarryG

Western Thunderer
Yup, Xuron track cutters here for distortion-free snips and less-filing afterwards. But there are always the thoughtless artists who never leave enough space for cutters so I keep old Kraft knife blades and break the blade ends off to five a guillotine cut using brute force & ignorance... :rolleyes:
 

jonte

Western Thunderer
Many thanks Heather, Simon, David and Larry for your help.

I feel a little more confident now about tackling my first etches.

And, Heather, some piccies would be great but in your own time, of course.

Fondest,

Jonte
 

mickoo

Western Thunderer
Yup, Xuron track cutters here for distortion-free snips and less-filing afterwards. But there are always the thoughtless artists who never leave enough space for cutters so I keep old Kraft knife blades and break the blade ends off to five a guillotine cut using brute force & ignorance... :rolleyes:
Not so thoughtless, you're paying for that extra space, everyone is paying for that extra space on etches.

People forget that etchers charge for the whole sheet, not just the parts on it, even fresh air.

Other peoples mileage may vary but I really do not like paying for something I'm not getting.

The W1 had over 600 parts, the standard gap was between 0.5 - 0.75 mm, if you double that then you can image how large the sheet will grow.

As Simon notes, well designed etches can have small gaps that allow you to get nippers or scissors in there, really really good etches (not guilty), have the parts you need first on the outside and then you work toward the middle.

Tags on the insides of curves is a hard one, it's a general rule that you don't do that, however, there are times when it's the only way.

Looking at Simons nameplates I'd struggle to find a better way personally, maybe just one tag in the middle.

You could risk it with just the two side tags but it does leave them awfully prone to damage between etchers and your model.

The correct way would be a carrier etch around each individual name plate, two tabs at each end and one tab at the top, but that would quadruple the real estate and free wasted space, and remember folks.....your paying for that space.

Back on topic, I use a large pair of Fiskars after Davids recommendation years ago, a Stanley knife, slitting disc in the mini drill, fret saw and tin snips, whatever does the job best really.
 
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mickoo

Western Thunderer
I used "binding" as a coverall term. You are more correct. What I meant was at this stage, without limiting the sideways movement of the wheels, all kinds of stickiness is apparent, but none of it a cause for concern. When I get the rest of the motion organised, I can decide on clearances and sticking washers in to stop things being too sloppy.

Meanwhile…

View attachment 117690

Everything just dry fitted to check things will work, but I’m happy with the etched slidebars. I’ve even got some little cast oil pots to go in on the top ones eventually. I really didn’t fancy attempting to fabricate the crossheads from the etch: one might get away with such things in 4mm scale.

View attachment 117691

As with the previous Prairie, I couldn’t use the NS etch cylinder wrappers as they’re just too thick to form sensibly. It only took 15 minutes to knock up new wrappers from thinner NS sheet, and here they are cooling down after being annealed a bit.

Getting there. Once these tedious jobs are out of the way, it should start to get more interesting. :D
Keep on swimming, swim , swim , swim :cool::thumbs:
 

adrian

Flying Squad
Don't you mean a wet herring.... :rolleyes: Kippers are the cold smoked product usually eaten for breakfast. ;)
I don't know - some will favour the oily option the sardines or the pilchard. Others the finest Cornish mackerel with its fine aerodynamic qualities. Some the distinctive mullet with its distinctive aroma although piranha are not recommended as they'll chew your arm off before you've even started.

 
Etch Extrication Tools and Techniques

Heather Kay

Western Thunderer
I love it when a thread wanders off course! :thumbs:

For what it’s worth, and basically reiterating what the others have said, I use different tools depending on the job. Here’s my current armoury:

D7A523B8-3F21-423E-8951-893BA1FA8D25.jpeg

I, perhaps heretically, will say that I find the Xuron snips singularly hopeless. Unless used with extreme care, more often than not the cut will fail, with the component flipping up and between the blades. I tend to avoid them when I can. The end cutters are used to snip back long tags on thicker etch material, once extricated from the fret, where other snips can’t get to it without bending or distorting the material.

DBBD1886-CAEB-4347-A4F1-291832A24365.jpeg

This is a pretty standard brass etch fret from our own David J Parkins. It comes from his Flightpath range of 1/72nd scale vehicle kits. This one will, one day, when I think my eyesight can stand it, be a Humber general service truck. With the parts economically and tightly packed on the fret, the safest option is a reasonably new No10 blade which can be rocked across the tag, close to the required component's edge, to break through the very thin material. If necessary, tags can be carefully trimmed back with the Fiskars scissors once the part is free.

3916DC1B-B729-4493-889B-D124EE58DAE5.jpeg

I'm not sure what they make their blades from, but this pair of Fiskars scissors has been through about five brass and nickel-silver kits and are still keen. In this case, I’m using them to free the component from the etch, snipping away from the part as there is a healthy gap to get the scissors into. Sometimes, it’s necessary to attack - as Mick said - from outside the fret and cut through the supporting material before you can free the part you want. On hefty etches, that’s where the Draper snips come in. If the tags are thin enough, the Stanley knife will do the job well enough.

I find the standard self-healing cutting mat good enough to use knives and scalpels against when cutting parts out. Your mileage may vary, of course.

F3365D0B-A1DF-47F7-A499-8E8964B0466D.jpeg

Here, I’m using the Fiskars again, this time aligning the blades with the edge of the part to trim back the remains of the tag. On this thick etch material, I’ll finish with a file, as there’s also a nice cusp to be dealt with. Small scissors like this can’t always deal with tags in awkward places, such as concave edges. In such case, if a knife can’t deal with it, I have to find a way to support the part and carefully file the tag away. The short length of the Fiskars blades also cause problems with leverage, where it isn’t always possible to snip off something using the extreme end. My generally weak and feeble fingers and thumbs don’t help there, either. :mad:

I hope that’s of interest. Like many of us, I’ve picked up tools and techniques as I’ve developed skills with kit building. Every modeller has techniques they like to use, and those above are just mine. I never profess to being an expert.
 
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