garygfletcher Posted May 6, 2016 Share Posted May 6, 2016 I've done an etch for the balcony at St Pancras, remember this is super small and actually my second etch of the same item. I cannot get the detail I want, mainly because the min etch line is 0.3mm. I just don't feel its close enough to be representative. I did think about doing the outline and using a jig to wind guitar wire and solder it into the shape. What are others opinions here? What would you do? Thanks g Link to post Share on other sites More sharing options...
garygfletcher Posted May 6, 2016 Author Share Posted May 6, 2016 Better pic of the balcony Link to post Share on other sites More sharing options...
garygfletcher Posted May 6, 2016 Author Share Posted May 6, 2016 As an ASIDE... here is an interesting comparison found in the national archives from last week... how Gilbert Scott originally designed them! Link to post Share on other sites More sharing options...
YesTor Posted May 6, 2016 Share Posted May 6, 2016 I just don't feel its close enough to be representative. What would you do? I think you've answered your own question, in that if it really doesn't feel right to you then it isn't right. I've anguished myself over similar seemingly small things and in the end you can either live with it, or if not it'll drive you mad the more you look at it. All that said, the basic shape looks right, but as you say, I guess that ideally it needs to look a bit finer. Link to post Share on other sites More sharing options...
garygfletcher Posted May 6, 2016 Author Share Posted May 6, 2016 I think you've answered your own question, in that if it really doesn't feel right to you then it isn't right. I've anguished myself over similar seemingly small things and in the end you can either live with it, or if not it'll drive you mad the more you look at it. All that said, the basic shape looks right, but as you say, I guess that ideally it needs to look a bit finer. The issue is at 0.3mm lines you just cannot do these shapes??? Link to post Share on other sites More sharing options...
RMweb Premium Neil Posted May 6, 2016 RMweb Premium Share Posted May 6, 2016 The delicacy of the real balcony railing is enhanced by its colouring, not dissimilar to the brickwork of the building. I'd suggest that the model may look better without the railing than with the comparatively chunky etched versions. Link to post Share on other sites More sharing options...
Yorkshire Square Posted May 6, 2016 Share Posted May 6, 2016 I don't know how much you have to do of this feature, but I'd suggest the following might work: Main posts: Fabricate from rods/tubes or 3D print. Some seems to be square, but with round finials. Top rail: Etch, full thickness for top, half etch for "droppers" and bottom of rail. Remaining rails/small uprights: wire. Small details: etched. You'd need to devise a jig to get everything square and evenly placed, but I think you'd get a better result than pure etching. Link to post Share on other sites More sharing options...
mike morley Posted May 6, 2016 Share Posted May 6, 2016 Version 1 might be a bit chunky, but I don't think you could describe version 2 that way. Seeing the actual etch, rather than just the artwork, would give a better idea. Link to post Share on other sites More sharing options...
billbedford Posted May 6, 2016 Share Posted May 6, 2016 Who is doing your etching? The simple way of doing this is to use thinner metal. The minimum etch line is a function of the metal thickness. PPD's thinest brass is 0.1 mm so the finest line you can produce is 0.12 mm, and if yo go to stainless steel the thinnest stock metal is 0.01 so the finest line becomes 0.015 mm. Link to post Share on other sites More sharing options...
RichardBenn Posted May 6, 2016 Share Posted May 6, 2016 I'd be more than happy with version 2 but perhaps my standards are not as high as yours. :-) If you etch in a thinner material you get a smaller minimum line thickness. 8 thou = 0.25. I believe you can go down to 5 thou but the resulting part is going to be very delicate! Using nickel silver will make the parts more robust than brass. Overscale etching in this scale is somewhat inevitable but it is surprising what you can get away with when it is in place on the layout, especially with sympathetic painting/weathering. In this scale especially it's the overall impression that counts and version 2 will satisfy that with ease. Link to post Share on other sites More sharing options...
Quarryscapes Posted May 6, 2016 Share Posted May 6, 2016 You can etch below 0.3mm too, but perhaps not over a long run like the railings. Features at full thickness surrounded by half etch can go as low as 0.1mm but it very much depends on the geometry and how well the etchant can replenish across the surface. Obviously the risk of the disappearing totally is there though if you do go below the minimum stated, however I do it all the time. Link to post Share on other sites More sharing options...
peter220950 Posted May 6, 2016 Share Posted May 6, 2016 Might it be worth having a word with the boys playing with lasers at the moment? They seem to be getting some fairly spectacular results http://www.rmweb.co.uk/community/index.php?/topic/108310-darkly-labs-emblaser-affordable-laser-cutter-review/page-3&do=findComment&comment=2227558 I'm sure oneof them would be happy to try a test piece if you have the CAD work? Peter Link to post Share on other sites More sharing options...
Adrian Posted May 6, 2016 Share Posted May 6, 2016 Agreed - from the same thread later on these two posts give an idea of what's possible. http://www.rmweb.co.uk/community/index.php?/topic/108310-darkly-labs-emblaser-affordable-laser-cutter-review/?p=2284530 http://www.rmweb.co.uk/community/index.php?/topic/108310-darkly-labs-emblaser-affordable-laser-cutter-review/?p=2284586 Link to post Share on other sites More sharing options...
RMweb Premium nick_bastable Posted May 6, 2016 RMweb Premium Share Posted May 6, 2016 Agreed - from the same thread later on these two posts give an idea of what's possible. http://www.rmweb.co.uk/community/index.php?/topic/108310-darkly-labs-emblaser-affordable-laser-cutter-review/?p=2284530 http://www.rmweb.co.uk/community/index.php?/topic/108310-darkly-labs-emblaser-affordable-laser-cutter-review/?p=2284586 you might get the details but in card not sure how strong it would be if you mail me a dxf I will give it a go for you Nick Link to post Share on other sites More sharing options...
garygfletcher Posted May 6, 2016 Author Share Posted May 6, 2016 Who is doing your etching? The simple way of doing this is to use thinner metal. The minimum etch line is a function of the metal thickness. PPD's thinest brass is 0.1 mm so the finest line you can produce is 0.12 mm, and if yo go to stainless steel the thinnest stock metal is 0.01 so the finest line becomes 0.015 mm. This is super useful and sounds like quite a viable solution. I should have mentioned that I am trying to fill an existing sheet of 0.25mm brass this is my second supplier. It has been quite a journey - I was sourcing suppliers while I was in China. Here you can see some comparatives and why I made the balcony lines thicker. It just so happens there was a mistake and rather than do a run of 56 - there is now a chance to make a new film hence my thinking here. The PPD 0.1 sounds like a good idea... I may try this. Img 1 = barlow roof Img 2 = first rubbish etch - 1st supplier Img 3 = second rubbish etch - 1st supplier Img 4 = having another go with another supplier - really good work, amazing price! Img 5 = the details at the end of the barlow roof which were etched really nicely - strangely by the first supplier! UK quote £250 per sheet x 56 thats £6,250 China quote... cheaper than I can buy a pice of A3 brass for in the UK etched! Link to post Share on other sites More sharing options...
garygfletcher Posted May 6, 2016 Author Share Posted May 6, 2016 you might get the details but in card not sure how strong it would be if you mail me a dxf I will give it a go for you Nick Hi Nick I have a laser cutter, but I would never get that out of it in a million years - this work is AMAZING! I would love to take you up on your offer, be great to see if this is a feasible option. I'll drop you a DXF/SVG over the weekend if that is okay? Best Gary Link to post Share on other sites More sharing options...
Caley Jim Posted May 6, 2016 Share Posted May 6, 2016 UK quote £250 per sheet x 56 thats £6,250 What!! Actually 56*£250 = £14,000!!! What size of sheet are you talking about? PEC's costs are £95 for photo tooling and then £20 per etched sheet. These for A3 size and 10thou n/s, both +VAT, which comes to £135 for your first sheet and then £24 for each sheet after that, so your 56 sheets would come out at £1423 + carriage. Even if your talking about a different tool for each sheet, it's still only £7560. The lattice, spectacle surrounds and ladder rungs on my signals are 0.13mm, half etched on 0.25mm n/s in the case of the lattice and rungs, full thickness for the spectacles. They came out OK with PEC, but with PPD the lattice was OK, the spectacle surrounds are there but very delicate and the rungs virtually disappeared! I'm sure something like 0.2mm would be OK. The good thing about PPD is that they will do sheets 300mm wide with a minimum 150mm long. Jim Link to post Share on other sites More sharing options...
garygfletcher Posted May 6, 2016 Author Share Posted May 6, 2016 What!! Actually 56*£250 = £14,000!!! What size of sheet are you talking about? PEC's costs are £95 for photo tooling and then £20 per etched sheet. These for A3 size and 10thou n/s, both +VAT, which comes to £135 for your first sheet and then £24 for each sheet after that, so your 56 sheets would come out at £1423 + carriage. Even if your talking about a different tool for each sheet, it's still only £7560. The lattice, spectacle surrounds and ladder rungs on my signals are 0.13mm, half etched on 0.25mm n/s in the case of the lattice and rungs, full thickness for the spectacles. They came out OK with PEC, but with PPD the lattice was OK, the spectacle surrounds are there but very delicate and the rungs virtually disappeared! I'm sure something like 0.2mm would be OK. The good thing about PPD is that they will do sheets 300mm wide with a minimum 150mm long. Jim What!! Actually 56*£250 = £14,000!!! What size of sheet are you talking about? PEC's costs are £95 for photo tooling and then £20 per etched sheet. These for A3 size and 10thou n/s, both +VAT, which comes to £135 for your first sheet and then £24 for each sheet after that, so your 56 sheets would come out at £1423 + carriage. Even if your talking about a different tool for each sheet, it's still only £7560. The lattice, spectacle surrounds and ladder rungs on my signals are 0.13mm, half etched on 0.25mm n/s in the case of the lattice and rungs, full thickness for the spectacles. They came out OK with PEC, but with PPD the lattice was OK, the spectacle surrounds are there but very delicate and the rungs virtually disappeared! I'm sure something like 0.2mm would be OK. The good thing about PPD is that they will do sheets 300mm wide with a minimum 150mm long. Jim Hi Jim, Yes your right my math was way off this morning - I do remember thinking I could build a real roof for the same! Well known model etcher.. they also couldn't do my size so suggested splitting the design. I think I may push my luck and go down to 0.1mm on this etch and see what it comes out like. Failing that it seems to take up PPD or PEC with a thinner metal. thanks, some great ideas in this thread! Link to post Share on other sites More sharing options...
billbedford Posted May 7, 2016 Share Posted May 7, 2016 If you are using Chempix, I wouldn't call them a model etcher. They got out of that market a few years ago by increasing their prices to match most of the other engineering etchers. There are three companies that still cater for the modelling/fancy work market, PPD, PEC and Grainge and Hodder. Link to post Share on other sites More sharing options...
Chris Higgs Posted May 30, 2016 Share Posted May 30, 2016 Hi Jim, Yes your right my math was way off this morning - I do remember thinking I could build a real roof for the same! Well known model etcher.. they also couldn't do my size so suggested splitting the design. I think I may push my luck and go down to 0.1mm on this etch and see what it comes out like. Failing that it seems to take up PPD or PEC with a thinner metal. thanks, some great ideas in this thread! Yeah as mentioned by Bill those prices are way higher than you will get quotes for from PEC or PPD (I have no experience with Grainge and Hodder). PPD is cheaper if you just want a sheet or two as their artwork cost is very low, but PEC will work out cheaper if it's for large volumes as they charge less per sheet. Getting back to the thin etches, you might be able to etch them very thin but will they survive in real use? If you want to use wire I would suggest using EZ-wire, which is thin rubber. It can be stretched down to a tiny size, and will just spring back into place if you happen to knock it. Alan Whitehouse uses this for overhead catenary. Chris Link to post Share on other sites More sharing options...
Quarryscapes Posted June 1, 2016 Share Posted June 1, 2016 Who are PEC? The invoice above is from 4D Modelshop. I've used them for a few things and they're OK, I wouldn't push the fine details with them though, In my experience they have a tendency to over etch. I really don't like the pre coated sheets of metal they use though, the finish on them is awful (same goes for PPD) and large areas of half etch tend to curl up. Here we go: The Taff Vale Railway lettering is 0.09mm stroke width. Etched in 10thou brass by 4D. Link to post Share on other sites More sharing options...
Nigelcliffe Posted June 1, 2016 Share Posted June 1, 2016 Who are PEC? Photo Etch Consultants, based in Walsall Link to post Share on other sites More sharing options...
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