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Post by 92220 on May 5, 2019 7:43:02 GMT
Nice one Roger! It looks as if that could work quite well.
Bob.
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Post by 92220 on May 5, 2019 8:03:57 GMT
I had a look for Aerogel insulation on the 'net. It is available in UK from a number of places, as rolls rather than the small pieces on Ebay, and it isn't too expensive if you look at the various sites. I have emailed Aerogel UK for a price list and will post prices for reference, when I get the details. It does look as if this is the answer to insulating boilers. It is available as blanket, in 3mm, 6mm and 10mm thicknesses. They take Paypal payment so I can't see their costs being too high either.
Bob.
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Post by Roger on May 5, 2019 8:09:51 GMT
I had a look for Aerogel insulation on the 'net. It is available in UK from a number of places, as rolls rather than the small pieces on Ebay, and it isn't too expensive if you look at the various sites. I have emailed Aerogel UK for a price list and will post prices for reference, when I get the details. It does look as if this is the answer to insulating boilers. It is available as blanket, in 3mm, 6mm and 10mm thicknesses. They take Paypal payment so I can't see their costs being too high either. Bob. Hi Bob, Thanks for researching that, it sounds very promising.
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Post by 92220 on May 5, 2019 8:20:25 GMT
Hi Roger.
I'll post the details when I get them. If smaller quantities (but bigger than Ebay) are not available. I'll perhaps look at getting a roll and selling pieces on here, cut to size, at cost plus postage if it works out not too expensive for the cut to size pieces.
Bob.
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Post by Roger on May 5, 2019 15:19:35 GMT
These are the parts printed overnight, taking about 5 hours in total. The flat plate could obviously been made from metal, but this is a quick test to check the dimensions before moving on to the detailed design. 20190505_094315 by Anne Froud, on Flickr And here's a wobbly video showing how freely the mechanism moves when you finally get the engagement of the gears right. This is attempt number three. I just printed out a new angle bracket each time. Lazy but easy to do. 20190505_161154 by Anne Froud, on Flickr I've currently got some scrap parts made from both PETG and PLA submerged in water that I'll leave for several weeks to see what changes, if any, occur. I know that all plastics are hygroscopic to some degree, so I need to find out what these particular ones are like. If they turn out to be unsuitable materials, I'll switch to metal parts and machine them. If it turns out that they change but very slowly over a matter of years, I'll probably just print out some spare parts and make sure the clearances don't cause an issue.
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JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,941
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Post by JonL on May 5, 2019 15:39:02 GMT
Very elegant design as usual Roger. Now get some moisturiser on those hands, you don't want industrial dermatitis!
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Post by Roger on May 5, 2019 16:15:26 GMT
Very elegant design as usual Roger. Now get some moisturiser on those hands, you don't want industrial dermatitis! I think you're probably looking at the prominent lines on my hands and drawing the wrong conclusion. I use a product called 'No more gloves' which is great for dry work and rinses off, taking the dirt with it. It dries to leave a white coating that tends to highlight all the crevices in your hands.
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JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,941
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Post by JonL on May 5, 2019 17:38:01 GMT
Ah yes, that sounds right, like a barrier cream. Fair enough!
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Post by Roger on May 5, 2019 18:24:44 GMT
Ah yes, that sounds right, like a barrier cream. Fair enough! Sort of, but it's only for dry work. It's ideal when you're filing or working on the car and the dirt gets driven into your pores to the point where you can't get it all out. I put it on for whatever I'm doing, it's better than nothing even if some of it does come off.
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Post by Roger on May 7, 2019 21:23:50 GMT
This is the second iteration of the water level gauge mechanism printed overnight. The tallest part was designed with printing in this orientation in mind, hence the gently sloping sides, inside and out which don't need supports. The small bevel gear is a different matter though. The boss is smaller than the gear teeth, so those need a supporting structure so there's something to print on when it gets up to that level. The Slicer program has been told to only create supports from the build platform to the underside of the parts. 20190507_085224 by Anne Froud, on Flickr This time it's printed out of PLA which is significantly more rigid than the PETG I used last time. The gears aren't especially good, but they're good enough after a bit of tidying up with a scalpel and needle file. This iteration has the support for the hinge moved to the other side of the quadrant arm. That's because there's very little room on the other side where the firebox protrudes the most. The base is 3mm thicker and it will be held by two bolts that will be soft soldered into the back plate. There will be two nuts holding this on. 20190507_114640 by Anne Froud, on Flickr The small plate prevents the quadrant from moving too far out of mesh. It's this part that would have been difficult to print if the bottom wasn't used at the print base. Vertical surfaces are easy to print. 20190507_114748 by Anne Froud, on Flickr I'm finalising the arrangement of the sealing arrangement for the back plate. Watch this space...
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Post by steamer5 on May 8, 2019 7:19:31 GMT
Hi Roger, Very nice! Wonder if I can slide a 3D printer past the financial controller!
On the sealing front, could you print the rectangular plate a bit thicker with an o-ring groove / recess on the side that bolts to the tank, assuming that’s the plan & you aren’t going to put this onto a brass plate?
Oh hang about you probably got some far more elegant plan!
Cheers Kerrin
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Post by Roger on May 8, 2019 7:26:20 GMT
Hi Roger, Very nice! Wonder if I can slide a 3D printer past the financial controller! On the sealing front, could you print the rectangular plate a bit thicker with an o-ring groove / recess on the side that bolts to the tank, assuming that’s the plan & you aren’t going to put this onto a brass plate? Oh hang about you probably got some far more elegant plan! Cheers Kerrin Hi Kerrin, It's definitely worth trying your luck to see if you can get one, they're not only useful but entertaining too! The problem with 3D printed items is that you can't guarantee that they will be watertight due to the way they are formed in layers. With a bit of experimentation and trial prints you would probably be able to get one that is watertight though. Although it's tempting to try this, I think the safest option is to create the seal with an 'O' ring between metal parts. At the moment I'm erring towards making the end plate of the tank from 6mm thick Brass, machining the 'O' ring groove in that and using the thickness to contain the blind fixing screws. It's not the cheapest option, but I'm very short of space in the side to side direction. So I wouldn't claim it's more elegant, but I think it might be satisfactory.
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Post by steamer5 on May 8, 2019 7:46:11 GMT
Hi Roger, Might have to work on the printer....... Somebody must of solved the inter layer water-ingress issue.
Just a thought & I have no idea if such an animal is made, how about a thin section grommet ?
Cheers Kerrin
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Post by Cro on May 8, 2019 7:54:47 GMT
Table Tennis balls work great as floats!
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Post by terrier060 on May 8, 2019 8:16:32 GMT
Sorry Roger - been out of touch with your thread as I have been away a lot recently. Are you using the 3D-printing to make castings from, or are you intending to use the plastic in the model?
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Post by Roger on May 8, 2019 9:04:30 GMT
Hi Roger, Might have to work on the printer....... Somebody must of solved the inter layer water-ingress issue. Just a thought & I have no idea if such an animal is made, how about a thin section grommet ? Cheers Kerrin Hi Kerrin, I don't think you will ever completely guarantee these parts as waterproof, it's just in the nature of the process. That's not to say that you can't achieve it on particular prints if you need it. This is one reason why these parts aren't considered to be 'food safe' either, there are too many potential voids and defects that can harbour bacteria. A resin printed part would fit the bill though.
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Post by Roger on May 8, 2019 9:05:26 GMT
Table Tennis balls work great as floats! Nice idea, but there isn't room, it's pretty narrow in the smallest section. I'll be able to use a piece of expanded Polystyrene as the float.
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Post by Roger on May 8, 2019 9:08:29 GMT
Sorry Roger - been out of touch with your thread as I have been away a lot recently. Are you using the 3D-printing to make castings from, or are you intending to use the plastic in the model? Hi Ed, The plastic parts will be used in the tank. The brackets, arm and gear will all be 3D printed but the attachment plate will be Brass. The printed parts will be bolted to the Brass plate. The intention is to use countersunk Brass screws threaded into the outer plate and to seal them with Soft Solder. The printed parts slide onto the screws which have become studs and nuts will be used to hold them on.
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Post by terrier060 on May 8, 2019 12:14:15 GMT
This process is even better than CNC!! Pity we could not afford the metal version!
Have you any thoughts on jointing compounds? ? I have just taken off the Princess cylinder covers and was able to remove the gaskets very easily after 30 odd years. The Blue Hylomar was still pliable and was used by Rolls Royce in their engines. Don't know whether the modern stuff is the same as the original. The cylinders never got hot, of course, but they do state that the adhesive does not set hard. Also I prefer metal-to-metal joints, but I suppose very thin gaskets would be OK if a suitable material was available.
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Post by Roger on May 8, 2019 15:21:21 GMT
This process is even better than CNC!! Pity we could not afford the metal version! Have you any thoughts on jointing compounds? ? I have just taken off the Princess cylinder covers and was able to remove the gaskets very easily after 30 odd years. The Blue Hylomar was still pliable and was used by Rolls Royce in their engines. Don't know whether the modern stuff is the same as the original. The cylinders never got hot, of course, but they do state that the adhesive does not set hard. Also I prefer metal-to-metal joints, but I suppose very thin gaskets would be OK if a suitable material was available. Fun isn't it! It uses so little material and requires no supervision, so you can print several iterations of an idea with very little cost or effort. I don't have any experience of jointing compounds other than stuff used years ago on old British motorbikes. How good any of it was is hard to judge because they always leaked like a sieve whatever you did. In the end i concluded that the castings were mostly porous, so the Hermatite might have been ok. If I was starting again, I'd make room for a 1.2'm wide slot on the cylinder ends and use a 1mm section 'O' ring. Gaskets are yesterday's technology in my opinion, and best avoided.
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