Author Topic: 2-knowledge...  (Read 4102 times)

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Offline 492

Re: 2-knowledge...
« Reply #15 on: Jul 19 2019 08:58 »
Have tried to add photos of the EMU bogies as attachments but they exceed the size limit. have you an email address that you would like me to send them to?

Robert. 492.

Offline John Candy

Re: 2-knowledge...
« Reply #16 on: Jul 19 2019 09:15 »
Robert,
Using "Add image to post" option (instead of attachment) will overcome the size limitation issue.
Regards,
John
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Branch

Re: 2-knowledge...
« Reply #17 on: Jul 19 2019 09:57 »
My newest project has a power bogie (2 motors) of 105mm wheelbase, and an unpowered one of 96mm.  Also, their profiles are totally different, this looks strange when all previous projects were symmetrical, but it definitely has its charms, and is a look to be embraced.

Offline 492

Re: 2-knowledge...
« Reply #18 on: Jul 19 2019 11:20 »
Thanks John, I will try that next time. I will email Bob as he has sent me a personal message re. the photos.

Robert. 492.

Offline cabbage

Re: 2-knowledge...
« Reply #19 on: Jul 20 2019 08:47 »
I have ordered the steel channel for the underframe of the emu. The laugh is that the postage is more than a third of the total cost... I have spent two day trying futilely to find the 11.5x8mm Aluminium channel. I have five sets of Chris Barron plans for coaches and they all use these "rocking horse droppings". B&Q stock the steel channel under the FFA/Concepts label. It is in convenient 1m lengths. I ordered the last
Aluminium channel from Poland -it came in 5m lengths and was stamped Alcan...

Because they are so common in his plans I have to assume that these must have been common in the UK at the time of drawing?

Again, some of the constructional timbers are not exactly common. Suppliers of very thin ply viz: 0.8mm are rare -but thin sheet wood isn't.

I will experiment with the laser cutter to see how easy it is going to be to cut window frames and the like.

Regards

Ralph

Offline John Branch

Re: 2-knowledge...
« Reply #20 on: Jul 20 2019 12:22 »
Ralph,
I've found 0.8 ply in commercial model shops like Antics and on line at Hobby's
John

Offline cabbage

Re: 2-knowledge...
« Reply #21 on: Jul 20 2019 20:33 »
John, I have tried an experiment in which I have written a script to print one of the window frames taken from the plans. The next part of the experiment is to use the laser cutter to produce a similar item in ply.

We will see what the winner is!

Regards

Ralph

Offline Peaky 556

Re: 2-knowledge...
« Reply #22 on: Jul 20 2019 21:34 »
Ralph, I can readily get you 0.95mm ply from my local model shop. Tim

Offline cabbage

Re: 2-knowledge...
« Reply #23 on: Jul 21 2019 13:24 »
After some experimentation -I have decided to print them. Some of the plan dimensions have had to be modified to produce a better print. The thicknesses are now; 1.0 and 1.5mm  only all the window radii are either; 1,2 and 3mm. The window glazing bars are all 2mm. That is 1mm wider than the plans but produces a far more robust window frame!

As with the "LMS Lego" series of Scad files these will be uploaded to the Wiki. Experiments with the laser cutter are "yes it works" but a production run of 32 windows would render the house uninhabitable!!!

Regards

Ralph

Offline cabbage

Re: 2-knowledge...
« Reply #24 on: Jul 21 2019 18:25 »
These are some of the windows off the RepRap. All of them were printed at a layer height of 0.06mm and a frame rate of 75%. The nozzle was at 210°C and the bed at 70°C. Each print takes around 30 minutes -which is far faster than I could do with a fret saw!!!





Regards

Ralph

Offline cabbage

Re: 2-knowledge...
« Reply #25 on: Jul 24 2019 07:55 »
I am now 18 windows down the required number... Todays the steel channel should arrive from B&Q plus the stuff ordered off eBay!





Regards

Ralph

Offline cabbage

Re: 2-knowledge...
« Reply #26 on: Jul 27 2019 11:33 »
Sorry for no recent update - but as you can see the hot weather and bad heart have slowed things down a lot. However regardless of how bad I feel the faithful reprap and laser etcher still function with little or no attention...  I have all the double window panels for both ends printed. This does not take very long but does mean that I have to keep getting up and down!

The next run are 60 window panes and 32 door panes... If I was the reprap - I would hold out for better working conditions!

The planned use for the etcher is for me to scan parts of the plans and then save them as .PNG format. Then it is a simple task to use the laserweb software and just click "cut this"...

I don't know if it is going to work yet but a few pieces of cornflakes packet may die horribly before I get it right(!)

Regards

Ralph

Offline cabbage

Re: 2-knowledge...
« Reply #27 on: Jul 29 2019 15:31 »
Only two cornflakes packets died in the quest. But as expected a scaling factor had to be applied to the Laserweb software. This normally expects .png files to be in a multiple of 300 dpi. I scanned a known sized part of the plan and then measured the cut size.

The "Monks co-efficeint was; (108/104)x600 or 577 dpi...

I have cut the template for the coach ends and will then cut out the framing foe them out of more cornflakes pkt and laminate to the correct thickness!





Regards

Ralph

Offline cabbage

Re: 2-knowledge...
« Reply #28 on: Jul 31 2019 13:05 »
This is the first test assembly of the chassis of the 2-nol.  The bogie centres are assymetric, the wheelbases are not the same and they look totally different! As anyone can tell - this is my type of loco!





Regards

Ralph

Offline cabbage

Re: 2-knowledge...
« Reply #29 on: Aug 05 2019 19:45 »
Tomorrow I dig out the band saw and start slicing the pieces of 1.5mm ply into campartment walls. I am going to cut the notches to 6mm rather than the 5mm in the plans as it will be stronger and I have 6mm pine stripwood in 2.4m lengths stacked up in the hallway! The front rooves of the loco are supposed to be carved from American Basswood - my response is "what planet are you from?" Anyone who knows me will tell you that I am inherently very lazy, thus is will be blocked out with ply and then P38 used to provide a smooth surface with...

This is actually proving to be the easiest loco that I have built. Without the reprap pouring window prints off its bed I could see myself getting very angry over having to make them. The reprap now has only four windows left to print and a couple of "frills" then it can go back into making normal things! Even with a power scroll saw a production run of 60 compartment windows would never have happened!!! But click the program file and wait a few minutes...

Regards

Ralph