Jon Nazareth's G3 workbench

geoff_nicholls

Western Thunderer
I note your comment about painting strapping. although all the open wagons I've built were all grey on the outside, the internal strapping and knees do need painting and it is very difficult, particularly the edges. Given the way you make your outer strapping in brass and use bolts etc, couldn't you blacken them, then add them after painting the basic body?
 

Jon Nazareth

Western Thunderer
Dear Geoff

I have thought of the problem with painting strapping and thought at some length on blackening the items before fitting. Some of the fittings, namely W irons, are held with real bolts and epoxy. With the straps and hinges, I use rivets as bolts and then slide the nuts on as dummies. The nuts are 16BA and at this size, they tend to stick together in the blackening solution making only half or no job at all and it is just so with the rivets. I also use a spot of glue to hold the nut on and this does tend to creep onto the strap. Generally, I can clean this off but it does leave a residue that gets covered over by the paint. If I were to try blacken first, I wouldn't have the chance to cover up any slight mishap and with all of those nuts, it could amount to quite a few. So, I've decided to spray everything and then just paint a few items below the sole bar.

Regards
Jon
 

Jon Nazareth

Western Thunderer
IMG_0218.JPG Dear Geoff

As a follow up to one of your previous messages, here is the little jig that I made to wind the links for the wagon safety chains. I made a similar but larger one for winding the links for three link couplings

Regards
Jon
 

Jon Nazareth

Western Thunderer
IMG_0212.JPG IMG_0214.JPG IMG_0216.JPG IMG_0214.JPG IMG_0216.JPG This is the next wagon on the list and I hope nobody out there is stifling a yawn. The other two pictures show how I line up and square the styrene sides to the ends during construction of the body using magnets and a machined and ground mild steel block. It works for me and is less fiddly than trying to use a corner clamp. The under frame for this wagon is in wood as I couldn't find any styrene/Evergreen strip deep enough for the solebars. When the body is finished, I shall most probably use an epoxy glue to fix it in place on the under frame. The curved tops to the ends, I am making from separate pieces as they over sail the sides. Yes, I'm sure that is how it was built originally and it took me ages to work this out from looking at the drawing.

Jon

IMG_0212.JPG
 

Jon Nazareth

Western Thunderer
Dear Jim

The wood that I used for the underframe was beech. If I'd had some sycamore or lime, I would have used that as they have a much tighter grain. I machined quite a lot of wood in different sizes some while ago thinking that I was going to make my wagons out of this material. Fortunately, I discovered styrene which is far easier for me to work with and so easy to join too.

regards
Jon
 

Jon Nazareth

Western Thunderer
Yes, styrene is so easy to use but not to file. I've been making the curved ends for the above wagon and it doesn't like to be filed or at least draw filed unless it's an old file that's being used. Still, I've done it now and there will be photos to follow once I've made the curved reinforcing strip. I've just glued up the mdf former and I'll give it a few more minutes while the glue sets.

I looked at the prices for the lime strips and thought them reasonable until I looked at the sheet! Think I'll stay with styrene.

Regards
Jon
 

Jon Nazareth

Western Thunderer
Bending styrene strip, 4 x 3mm, isn't as easy as I imagined. Tried immersing in boiling water and even used the hair dryer while it was in the former but no doing. So, it's back to the drawing board and as Scarlett once said, Tomorrow's always another day. I think the strip is a bit on the heavy side but that's the size it needs to be. I was going to saw it from a 3mm sheet but the thought of trying to clean up the cut edges put me off that idea.

Jon
 

JimG

Western Thunderer
Yes, styrene is so easy to use but not to file. I've been making the curved ends for the above wagon and it doesn't like to be filed or at least draw filed unless it's an old file that's being used.

I prefer to scrape the edge of styrene using my knife blade, rather than file it. Although these days I tend to mill it to shape in my CNC mill which makes life a lot easier for ageing hands and eyes. :)

I looked at the prices for the lime strips and thought them reasonable until I looked at the sheet! Think I'll stay with styrene.

The sheet price is actually slightly cheaper than strip by the square inch. :) But the prices of the thicker sheets certainly would put a dent in the wallet. And postal prices might make a difference as well. I've had strip from Cornwall before and the price for postage was quite reasonable. But that might have been for materials that would go in a 5cm diameter postal tube. 10cm wide sheet might be another matter altogether.

Jim.
 

JimG

Western Thunderer
Bending styrene strip, 4 x 3mm, isn't as easy as I imagined. Tried immersing in boiling water and even used the hair dryer while it was in the former but no doing. So, it's back to the drawing board and as Scarlett once said, Tomorrow's always another day. I think the strip is a bit on the heavy side but that's the size it needs to be. I was going to saw it from a 3mm sheet but the thought of trying to clean up the cut edges put me off that idea

Jon,

When forming the tumblehome on my styrene coach sides, I used a former and "cooked" it in my oven at 100C - noted here in this message in my thread on the coach construction

http://www.westernthunder.co.uk/ind...-stock-for-banavie-road.700/page-4#post-18777

In that message I mention that the parts were kept in the oven for ten minutes, but I think that subsequently I found I had to increase that time to nearer twenty minutes and pre-heat the alloy former as well. My test when the piece was removed from the oven was to release one of the clamps and see if the Plastikard sprung up. How long were you immersing the part in the boiling water? It could be that you might have to immerse it for much longer, and your former might be acting as a heatsink and holding the temperature of the styrene down and a longer immersion would get the former up to boiling point.

Another method I use for curved styrene shapes is to laminate the curve from several layers of thinner material stuck together with MekPak, the thinner material bending to the curve quite easily. When left to set hard, the curve is held very well. You will probably have to smooth off the sides, but that could be comparatively easy to do.

Jim.
 

Jon Nazareth

Western Thunderer
Dear Jim

I've looked at your work and it is truly impressive. It puts all of my efforts quite in the shade.
I've taken on board all of your comments and may try putting my MDF jig in the oven....it should be okay at 100 degrees...I think. I must admit, I didn't think of laminating although, wouldn't the edges show a little? Lots of things to try but I'm busy until Sunday so, will give some a go after I've cut the lawns :(.
LBSCR had a passenger brake not so dissimilar to yours and I would love to have a go at building it in G3 but with all of that panelling, I don't think I have the skills. I'm going to try and download a 7mm version that I have.

Thanks for the tips, Jim, I will certainly IMG_0243.JPG IMG_0244.JPG give them a go.

Regards
Jon
 

JimG

Western Thunderer
Jon,

The consideration with the laminating method is disguising the laminations on the sides although I have managed that in the past with careful sanding to smooth the edges as far as possible then painting and sanding if the edges are still apparent. Funnily enough, I'm just thinking about that at the moment as I consider making something where I will have to laminate to get the proper thickness for a part and hiding the laminating joint will be the main consideration since the laminated area will be in full view.

I have used aluminium alloy for my formers for the oven up till now but I've been thinking about using MDF since it's a lot cheaper. I should think that it will probably be fine at 100C. But I'll have to go and find some decent MDF since the stuff out of my local B&Q is more like hard cardboard. :)

Jim.
 

Jon Nazareth

Western Thunderer
IMG_0241.JPGThis is the first former that I made and the curve was wrong. I made another former with a third 'block' positioned at the top of the it. But, I thought to myself that I would make it a little smaller to allow for spring back, WRONG! There was no spring back and the styrene cam out perfectly if a little small. Instead of making another former, which I should have done, I worked the styrene by had until I got it right and then fixed it in place on the wagon. The former worked very well and the result would have been perfect if I had made it the correct size. My oven doesn't go down to 100 degrees so, I cooked it at 150 C for twenty minutes without harm to styrene or MDF former. If I'd only made the former the correct size.....:(
IMG_0241.JPG
 

JimG

Western Thunderer
Jon,

Success. :):) As you've found out, there should be no spring back if it has set properly in its new shape. As I said before, my test when taking the piece out of the oven was to release the clamps and see if the part sprung back by any amount. If it did, it was re-clamped and poked back in the oven for a bit more treatment. :)

Jim.
 

Jon Nazareth

Western Thunderer
Is there an easy way to cut styrene patterns for use on a pantograph? Someone has offered to cut a (some) spring hangers for my open carriage truck but I have to make the pattern :eek:

Regards
Jon
 
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