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Post by greasemonkey on Dec 2, 2006 23:27:30 GMT
Hi All Here are some more parts that I have fabricated recently. These are the expansion link and motion brackets for a Les Warnett 5" guage 9F that I am building. This isnt my main project so I tend to mnake the odd part occasionally just to keep it ticking along. As I was getting some parts water jet cut for another project I drew these brackets up at the same time. They are cut from 2mm steel rather than the 3mm brass specified originally. The 2mm is nearer to scale and is more than strong enough, scale would have been 1.5mm and I think this would also have been suitable. They are fabricated in a jig with tabs to hold the individual parts in the correct relation to each other. I havent cleaned them up properly, just enough to give them a coat of protective primer whilst they await their trun along with the other 1000 or so parts all sititing in 5, 5 liter ice cream containers under the bench .       cheers Andy |
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Post by Shawki Shlemon on Dec 6, 2006 6:48:08 GMT
Is all this ice cream you eat makes you make such a nice job. Will be asking my wife to buy more ice cream from now on , may be I can do the same . A very good job , well done .
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Myford Matt
Statesman
There are two ways to run a railway, the Great Western way, and the wrong way.
Posts: 621
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Post by Myford Matt on Dec 6, 2006 19:57:12 GMT
Always interesting to see fabrications - nice pics too
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Post by standardsteam on Dec 13, 2006 11:14:35 GMT
Great work! It seems fabrication is much more appropriate to create some of the bracketry associated with the standard classes. As a newbie I have loads of questions in my mind about this which is probably obvious to the experienced hands like:
Did you draw and create the patterns for cutting?
How did you hold the parts during the fabrication stage?
Are they silver soldered?
What allowance do you make for the tabs/solder joint in the pattern?
Is the sprue on the parts for convenience or as an artefact of the cutting process?
If anyone could point me to a resource on fabrication appropriate to models I would appreciate it!
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Post by greasemonkey on Dec 13, 2006 13:55:48 GMT
Hi Standard Steam Fabrication is the sensible answer to a lot of parts especially given the cost of castings and on the BR Standards a lot of parts were fabricated anyway. The parts above were redrawn from the original Les Warnett design with additional reference to the full size Prototype. The drawings were created by me on a CAD package (I use Autosketch from the Autodesk stable). Initially I draw the outlines of the various parts and then add tabs and matching slots at the relevant places to help with alignment, but you do need to have some idea how it is all going to go together when you first start. You could just use tabs to hold all the bits together and I heard about someone doing just this at the weekend. Personally I used a jig to maintain the critical parts in the correct position to one another whilst silver soldering. The ideal way to solder them would be to vacuum braze them as will save having to clean up a very awkward shape. Fortunately one of my clubs has got a grit blasting cabinet. I didn't leave any allowance for the solder in the design preferring to add a little at the fitting stage before soldering. The sprue is necessary to help the cutting. It is possible to cut them without but hate parts being so Small can get lost and the sprue is a convenient method of keeping all the bits together. There is a good article on fabrication at the Malden Club website here www.malden-dsme.co.uk/newsite/fabrication.htmcheers Andy |
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Post by standardsteam on Dec 13, 2006 16:32:32 GMT
Many thanks for your informative reply, I'll have to have a go at this sometime in the future... vacuum brazing also sounds like something else I need to find out about!
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Post by Laurie_B on Dec 14, 2006 14:09:36 GMT
Whilst on the subject,here are a few photos of the fabricated drag box for a 5" gauge BR3 tender (as for the BR class 2 loco) I made recently. 1st pic,the parts held together with 'slot and tab'.All nice,shiny steel!  2nd photo-after silver soldering.A very colourful mess!The wood blocks were put under the drag box after it had cooled down.  3rd image,after cleaning up and after the drag beam and tender-engine buffers were fitted.  |
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Post by greasemonkey on Dec 14, 2006 14:29:05 GMT
HI Laurence
Nice work, did you use the Don Young drawings or research and build your own? I want to remake both drag boxes for the 9F in the same style as what you have done. How did you clean your fabrication up? I think the biggest mistake I made was not leaving the tabs long enough to clean up afterwards. Did you have any problems with distortion on such large plates and who did your water jet cutting? Finally how did you hold it together for soldering, I found the odd strategic centre punch helped!!
Andy
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Post by Laurie_B on Dec 14, 2006 16:42:36 GMT
Hi Andy.
The Don Young drawings for the Class 2 loco/BR3 tender are a bit short on detail to be honest.So I otained a few copies of works drawings from the NRM,one of which was SL/DE/20521 "Front Dragbox".The works drawing detail made me go a bit cross-eyed!So I simplified the design somewhat,mainly for ease of construction.
I cleaned up the fabrication with wire brush,emery and steel wool.I want to try using citric acid at some time for acid cleaning up the mess that silver soldering leaves.
There wasn't any noticable distortion,the subsequent machining went without any problems.
Apart from the 'slot and tab' locations,there are a number of 10 BA screws just holding the top and bottom plates in situ.Also there are 2 off 3/4" x 1/4" steel strips between the plates which probably prevented any noticable distortion too.
The fabrication was gently warmed through before starting the silver soldering,and was allowed to cool slowly when complete.
I had the plates cut out by Sciss Ltd of Staplehurst in Kent.After a touch of draw filing the edges,all the parts fitted together very well,as they were very accurately cut out.
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dscott
Elder Statesman
Posts: 2,438
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Post by dscott on Dec 17, 2006 21:26:52 GMT
Dear G.M.
What a lovely set of photos, it is almost a shame to hide some of these on a loco once it is finished, almost as if it would be nice to make another part, just for a conversation piece on the sideboard. Up to now I have done this the hard way and cut machined filed and soldered
the bracketry mostly on G.W.R. stuff.
David.
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Post by havoc on Dec 28, 2006 21:39:18 GMT
Stumbled on his while just browsing around. I'm pleased to see such parts made the way you do. It gives me confidence to try it as well. Thanks for that.
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Post by thefodenman on Jan 19, 2007 20:42:09 GMT
Hi Andy, Iam very inpressed with your reverser brackets any chance of a set?. Iam restoring a 9F which I brought from Maxitracs, a year or so ago, the brackets on the loco are quite poor, would you be willing to discuss a price for a assembled pair of brackets or perhaps be able to supply the laser cut parts?  please get in touch, regards, Another Andy |
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Post by greasemonkey on Jan 20, 2007 20:19:36 GMT
Hi Andy
Have sent you a PM but I am quite happy to supply laser profiles.
Andy
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John Lee
Part of the e-furniture
Posts: 375
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Post by John Lee on Jan 21, 2007 16:30:02 GMT
Hi Andy Have sent you a PM but I am quite happy to supply laser profiles. Andy Copy me in Andy if you will. I have always fancied starting a 9F in 5" as a long term project, like yourself. Regards, John |
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John Lee
Part of the e-furniture
Posts: 375
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Post by John Lee on Jan 22, 2007 18:37:48 GMT
Hi Andy Have sent you a PM but I am quite happy to supply laser profiles. Andy Copy me in Andy if you will. I have always fancied starting a 9F in 5" as a long term project, like yourself. Regards, John Bump! More info Andy?? |
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John Lee
Part of the e-furniture
Posts: 375
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Post by John Lee on Jan 24, 2007 18:07:36 GMT
Hi Andy Have sent you a PM but I am quite happy to supply laser profiles. Andy Bumping again..sorry..you can supply for a 9F?? |
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Post by greasemonkey on Jan 24, 2007 18:59:50 GMT
Hi John
PM on its way.
Andy
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please get in touch,