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Post by drjohn on Mar 28, 2011 9:14:20 GMT
Hi Norm, thanks for the welcome back.
Problem is I need to hold about 6 or 7 pieces together in the right relationship (frogs won't help) and do a one-off silver solder of the whole fabrication - hence the rivets just as locators to hold the bits in the right place - not rivetted, just pushed in as locators into blind holes on the edge of 3mm plate. If you get what I mean, then the heads filed off later.
DJ
Apologies Pete - not hijacking your extremely interesting thread.
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Post by Shawki Shlemon on Mar 28, 2011 9:19:04 GMT
Welcome back DJ , if rivets are not bashed , silver solder will flow because holes will be slightly larger .
If you can't get 1/16 drills there send me your address and I will send you a few , no problem .
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Post by Deleted on Mar 28, 2011 9:31:46 GMT
Hi DJ Good to see your still around as I hope all others are too. Regarding the spring hanger brackets yours certainly look more involved than mine( my fabrication for these is covered in this thread) I'm not familiar with the Black 5's tender so can't really compare it with mine. When you say "box stretchers" I'm assuming you mean the drag and draw boxes? ( well I did say this is all new to me:)...) If so Don's a little vague for the Doncaster as well, there he says to hold the parts together with 8BA screws for silver soldering which I never fully understood as at that stage there are no drilled holes in the steel for this and even if you transferred the holes into the end pieces first most are 6BA not 8 and screws don't come in over 6" lengths even if there was a free route to pass them ( or studding ) all the way to hold the box parts together for soldering. I'm probably totalling misunderstanding Don's words and his meaning will be obvious to the more knowledgable folks on this forum, but since I went the laser cut route as already mentioned all I had to do was clamp the parts together for silver soldering and then machine down to the 6" overall size, no screws of any sort involved. BTW I had a good look at your Black 5 build, very nice, I like the Black 5's, nice looking loco's Regards Edit: just read your reply above DJ regarding what the rivets ate for, makes sense now although not so clear on Doncasters words, still you live and learn...  Pete |
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Post by goldstar31 on Mar 28, 2011 9:47:05 GMT
DrJ and all, apologies for the Hi Jack but I feel it important.
Once silver solder has bonded to its intended part, it changes its melting point. Consequently, one can do part solderings in relative safety to apply further same grade silver solder for a second operation.
Off at another tangent, you can use silver solder paint to stick parts down instead of stick solder.
I'm more into leading and bashing car body panels but the principles are pretty similar.
N
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Post by Deleted on Mar 28, 2011 9:59:13 GMT
Hi Norm
Yes your right about silver solder having a higher melting point once used as I'm sure DJ will know too. Your post has pointed out to me though that perhaps I didn't explain myself well enough in soldering the boxes together. DJ I didn't solder all of the parts in one go which is how Don suggests in his words and music, that's certainly how it comes across for Doncaster. As Norm has pointed out you can do it in sections which is what I did first getting two parts together squarely and then working from there. I used various clamps for both holding the parts together but also strategically placed to act as heat sinks protecting previously soldered parts as I worked my way through the construction. I also forgot to mention that I used a propane/oxy torch to give me more heat once the parts had been warmed up first to help avoid distortion.
Pete
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Post by drjohn on Mar 28, 2011 10:06:31 GMT
Thanks for that Pete and Norm - I'll fiddle and see what transpires. I'll let you know in the fullness of time.
Cheers
DJ
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Post by Deleted on Mar 28, 2011 17:11:40 GMT
Just one picture today guys but it does represent a weeks work so I'll post it before I place these little devils on the frames. Pic214 The completed spring hangers, all 16 of the little buggers...lol these items are one of those things that you could keep working on but I've drawn the line here as I have plenty more to do elsewhere. Although a template was used there are in some cases slight differences but considering these are basically hand carved I'll live with them. Mind you once painted I doubt you'd notice anyway, one things for sure if I'm going to continue with live steam next time i do these I'll make a pattern and go the lost wax route.. BTW today I received the new spring material from Reeves ( not bad considering I only ordered it Friday) so I'll get on with the springs first and then make the buckles so that they are a nice fit around the assembled springs. Oh and for some reason this material is in an annealed state so I'll have to find that site I've seen before with guidelines on hardening spring steel. Regards Pete Attachments:
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Post by Deleted on Mar 31, 2011 19:40:58 GMT
Good evening guys and gals Tonight I'm going to describe the fabrication of the leaf springs and I'd like to start by saying thank you to Tel for his advice on tempering the steel. Pic215 In the picture is the various steel components cut to size ready for bending to shape. The piece of wood is a piece of 2x1 that I have cut to the profile needed for the 1/4 camber this will be used to shape the steel so all leafs are correct. Note: sorry guys I seem to have a problem with proboards not letting me load any more, I use proboards for uploading pictures, I'm getting an error stating I should contact admin. Give me a little time while I try to find another way to get the pictures uploaded. Back soon Attachments:
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Post by Deleted on Mar 31, 2011 21:41:13 GMT
ok think ive sorted out something, lets try
pic217
the picture shows me using the bottom profile piece , rubbing a suitable piece of alloy bar across each leaf to form it's shape. For the large leafs i used this method ( using both hands of course) , for the small ones i used a small hammer to rapidly tap the alloy while moving it along the length of steel.
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Post by Deleted on Mar 31, 2011 21:44:44 GMT
Picture that should have been in previous post, don't you love computers.. Attachments:
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Post by Deleted on Mar 31, 2011 21:46:04 GMT
Pic218 The steel leafs all shaped ready for hardening Attachments:
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Post by Deleted on Mar 31, 2011 21:52:30 GMT
Pic219 The leafs hardened ready for tempering, I was going to take a picture during the tempering stage but found I was a bit busy. I used Tel's suggestion using tallow in a tray to temper the leafs, I coated each leaf first with tallow and then put all of the leafs into a tin tray and with some more tallow and lit it. Sounds easy eh? Yeh right, it takes a fair bit of heat to ignite the tallow although Tel did make a reference to this in an old thread. Attachments:
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Post by Deleted on Mar 31, 2011 22:01:59 GMT
Pic220 Next job was to braze on the 1/8 rods to the top leaf that's held by the hanger grip. Don suggests using a potato with just enough sticking out for brazing the rods on. I tried this but found it difficult keeping the rods square as naturally the potato moves when heated. So I settled for laying the leaf on a magnetic bar with a piece of steel either side, the leaf was scribed 1/16 in from it's end and the scribed line was used to keep the leaf square by lining it up with the two pieces of steel. It was easy then to paste the rod and spring and then lay the rod in place, since the leaf was lying on a magnet everything was held together for brazing. All this metal acted as a heat sink so helped keep the rest cool, btw the leaf hasn't been cleaned yet which is why it's black in the middle. Attachments:
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Post by Deleted on Mar 31, 2011 22:07:44 GMT
Pic221 A finished set of leafs at last, the picture shows both the steel and tufnol leafs that make up the spring, the others are also completed except for polishing which I'll get done tomorrow. The hangers fit nicely and can not be pulled out, they have to be slipped in so I guess I built the gripper correctly... Next is the buckles, once all parts are made I'll be able to see what's needed to get the correct spring loading, if too strong I can always replace some steel for tufnol, trial and error will be the order of the day. More soon .. Attachments:
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Post by Deleted on Mar 31, 2011 22:10:55 GMT
Hi Mike Yes thanks for the suggestion, I did see it while uploading.. Not sure what happened, for some reason the proboards app began to play up and refused to upload pictures...lol Seems ok now though |
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Post by drjohn on Apr 1, 2011 11:40:41 GMT
Hi Pete Having seen the traumas you've gone through to make those springs, I'm seriously tempted to make a wooden pattern and cast them solid in aluminium alloy and put a hole in the middle for a coil spring!  DJ |
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Post by Deleted on Apr 1, 2011 12:03:05 GMT
That's certainly an option DJ, I have seen that method mentioned before and it certainly sounds good to me while sitting here spending hours polishing these leafs. My problem is I would never be satisfied with it, I have the same problem if building a kit, I always have to make it better, sometimes I envy those who can build things straight out of a box. I've never managed to do that which probably explains why I have so many unfinished models....  Must finish polishing, I need two pairs of hands or more...... Pete |
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Post by Jim on Apr 1, 2011 17:16:13 GMT
I think DJ has a point there Pete. Sometimes what works in 12":1' doesn't necessarily translate to the scales we work in, so that much as I love fine detail and fine scale work, a compromise cleverly disguised of course, has to be made. My springs on Boadicea are as DJ describes them with working and and adjustable coil spring inside each leaf spring. I might add I have started to realise that with greying hair one faces the prospect that ones modelling life might just be finite  Having said that please keep up the beautiful and inspirational workmanship Pete. Jim |
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Post by Deleted on Apr 1, 2011 17:57:58 GMT
Thanks Jim It must have been from you that I have heard DJ's suggestion before, I agree it would be a lot easier to both build and set up. Certainly right now the springs are a little stiff or they seem so to me but you can't really tell by just forcing the spring down. Once they've fitted to the chassis I'll have a better idea whether they need extra tufnol leafs or not after all they have to support the full sprung weight of the tender and that's no light weight for sure.... Pete |
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Post by Shawki Shlemon on Apr 2, 2011 8:37:20 GMT
We have a great hobby . What make it so is that thousands of people in this hobby have different ideas / options / standards / patience which make every model interesting . As long as the builder is satisfied with the product whether it is 50% , 60% , or 80% correct does not really matter .The main objective is having good time making and operating the model .On few of my engines I have used DJ option . If all the models were to pete standard then pete wouldn't be so popular on this board .Well done pete , you have to do what you have to do . ;D
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