---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Tue 11/25/03: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:23 AM - Re: Faulty scales (Paul Sweeting) 2. 07:40 AM - Re: Faulty scales (Paul Sweeting) 3. 10:43 AM - Re: UK Weekday Fly-in (Dari Sagar) 4. 01:56 PM - Re: XS Fuel System Mods. (Jeremy Davey) 5. 02:14 PM - Re: Faulty scales (Jeremy Davey) 6. 02:17 PM - Re: Faulty scales (Jeremy Davey) 7. 10:30 PM - Re: UK Weekday Fly-in (William Mills) 8. 10:43 PM - Last Minute...? (Matt Dralle) ________________________________ Message 1 _____________________________________ Time: 07:23:18 AM PST US From: Paul Sweeting Subject: RE: Europa-List: Faulty scales --> Europa-List message posted by: Paul Sweeting Hi Jez, Very intresting - especially as I decided to purchase the My-weigh i500 with 500g capacity and .1g resoution, but its out of stock at right on scales http://www.rightonscales.co.uk/i500.htm, probably cos its 20 cheaper here at 55 than elsewhere . So therefore are you inferring that 0.1g is too low a resolution or specifically the mechanism of the scales is at fault, i.e some scales react this way whilst others do not?? Don't tell me to be assured of the correct accuracy, a balance with a lot higher resolution at a lot more cost is required... Cheers Paul.. -----Original Message----- From: Jeremy Davey [mailto:jeremycrdavey@btinternet.com] Subject: Europa-List: Faulty scales --> Europa-List message posted by: "Jeremy Davey" You may remember a thread some weeks ago started by Ron Parigoris about problems with digital scales that ignored any very small, very slow increments in weight? His test involved weighing a piece of Letter paper, then tearing it up and reweighing it, putting the pieces on very slowly. After a long search for a piece of Letter-sized paper to undertake the test (we use A4 over here) I tried it and, to my surprise, my scales failed! Now this was potentially a serious problem. I measure Ampreg 20 by weighing a pre-decided weight of resin, then adding hardener with a syringe, slowing to a drop at a time at the end. I'd often found that the last 0.5g or so (my scales have 1 decimal place) took a lot more drops of hardener than expected. Now I knew why! Fortunately for me I had discovered a few days previously that a friend in the village is a representative for a well-known laboratory scales company. I'd had problems reading my scales from some angles ever since I tried to wipe off some drops of resin/hardener with an acetone-soaked piece of paper towel (D'oh!!) and got a semi-opaque screen. He'd offered me a redundant sample from his large stock. With my new scales, the sort that have a spirit bubble and are accurate to 0.001g, I found that a drop of hardener weighs 0.03 to 0.05g. So what was the worst-case scenario? My best guess was that in the worst cases I'd added 10 extra drops, making the mix with 0.5g excess hardener at most. The smallest mixes I'd made were 40.0g resin + 10.0g hardener in order to keep the proportions within the accuracy (!!) of the scales. So these cases could be up to 5% excess hardener. I checked with a number of people for an opinion: my inspector, the Europa Factory, Dr. Bill Brooks of Scrapheap Challenge and Pegasus Aviation fame (a top bloke!). No-one knew for sure if I'd have a problem - and so far I'd done the tail, ailerons, flaps, XS wings and Cockpit module. I didn't want to ask SP Systems because I feared the litigation-aware response of 'if the ratio is wrong, you must redo everything'. Bill's suggestion was to call SP Systems, and he did have a point, so I rang Martin Armstrong in their product support (who I knew was excellent from previous experience with another question). To cut a long story short, Martin suggested the eminently practical idea of making up a deliberately worst-case-scenario batch of epoxy using my old scales and usual technique, cure it for three days, then send it to them for testing. The results were most interesting, and I'm in the clear - the sample was strong enough (PLEASE DO NOT TREAT THIS AS AN EXCUSE TO BE LESS METICULOUS IN YOUR EPOXY RATIOS!!). Strangely enough the sample gave indications of being cured at 50C - I hadn't done this (I heat the workshop to a consistent 22-24C) so I assume the striking postal workers must have left it over their brazier for a few days. I wanted to tell this story in order to encourage people to check their scales for the issue, and also to publicly thank SP Systems for the high quality of their product support. I was a very worried chap for a while. Once again I am glad I chose the kit I did, and that the various suppliers of parts are fully behind their products. Regards, Jeremy Jeremy Davey Europa Monowheel 537M G-EZZA Tail done Standard XS wings awaiting mods and closing CM ready for installation in fuse (with airbrakes fittings) 1100 build hours to date Intended fit: Rotax 914 turbo, Airmaster CS fully-feathering prop Lots of lights, buttons, switches, gizmos, and alarms The contents of this email and any attachments are sent for the personal attention of the addressee(s) only and may be confidential. If you are not the intended addressee, any use, disclosure or copying of this email and any attachments is unauthorised - please notify the sender by return and delete the message. Any representations or commitments expressed in this email are subject to contract. ntl Group Limited ________________________________ Message 2 _____________________________________ Time: 07:40:30 AM PST US From: Paul Sweeting Subject: RE: Europa-List: Faulty scales --> Europa-List message posted by: Paul Sweeting But do now recall in my chemistry days being taught to always take the item off and then place back on the balance after addition or subtraction.. So the correct method to overcome this would be to add a drop or two, then take cup off balance and place back on, before adding more?? Cheers Paul.. p.s surely you mean ISO A4 not A4..... i.e 297mm X 210mm not 11.?" x 8.?" - how do I know the difference, lots of very expensive pre-printed cheques that didnt quite line up........ -----Original Message----- From: Jeremy Davey [mailto:jeremycrdavey@btinternet.com] Subject: Europa-List: Faulty scales --> Europa-List message posted by: "Jeremy Davey" You may remember a thread some weeks ago started by Ron Parigoris about problems with digital scales that ignored any very small, very slow increments in weight? His test involved weighing a piece of Letter paper, then tearing it up and reweighing it, putting the pieces on very slowly. After a long search for a piece of Letter-sized paper to undertake the test (we use A4 over here) I tried it and, to my surprise, my scales failed! The contents of this email and any attachments are sent for the personal attention of the addressee(s) only and may be confidential. If you are not the intended addressee, any use, disclosure or copying of this email and any attachments is unauthorised - please notify the sender by return and delete the message. Any representations or commitments expressed in this email are subject to contract. ntl Group Limited ________________________________ Message 3 _____________________________________ Time: 10:43:53 AM PST US From: "Dari Sagar" Subject: Re: Europa-List: UK Weekday Fly-in --> Europa-List message posted by: "Dari Sagar" William, Count me in ....if the weather holds. Regards, Dari >From: "William Mills" >Reply-To: europa-list@matronics.com >To: >Subject: Re: Europa-List: UK Weekday Fly-in >Date: Tue, 25 Nov 2003 07:05:45 -0000 > >--> Europa-List message posted by: "William Mills" > > >Dear All, > >THURSDAY is still looking good for SLEAP. I will only change it if the >weather slot moves Please give me an idea who is going to attend for the >catering request. > >Regards, > >William > > Find a cheaper internet access deal - choose one to suit you. http://www.msn.co.uk/internetaccess ________________________________ Message 4 _____________________________________ Time: 01:56:56 PM PST US From: "Jeremy Davey" Subject: RE: Europa-List: XS Fuel System Mods. --> Europa-List message posted by: "Jeremy Davey" Mike, Your mod paperwork should be with you by now - let me know if any questions! Cheers, Jeremy Jeremy Davey Europa Monowheel 537M G-EZZA Tail done Standard XS wings awaiting mods and closing CM ready for installation in fuse (with airbrakes fittings), but holding off while I do a load of small jobs first 1100 build hours to date Intended fit: Rotax 914 turbo, Airmaster CS fully-feathering prop Lots of lights, buttons, switches, gizmos, and alarms -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of Mike Subject: Re: Europa-List: XS Fuel System Mods. --> Europa-List message posted by: "Mike" Jeremy, My sight guage will be fed from the same line as shown in the manual. The factory fuel drain mod has the guage T'd iinto the port drain line which gets its supply from a separate pipe within the tank so air cannot be sucked in. Incidentally, any chance of you letting me have a copy of your mod submission for the pip pin covers? Regards Mike ________________________________ Message 5 _____________________________________ Time: 02:14:33 PM PST US From: "Jeremy Davey" Subject: RE: Europa-List: Faulty scales --> Europa-List message posted by: "Jeremy Davey" No, no. You're fine at 0.1g resolution. The issue is that if the resin/hardener being weighed is added very slowly, it ignores the increase! Ron published a test where you weigh a piece of paper, then tear it up and add a small piece at a time, waiting time between adds. It takes some time to do right, but with my faulty scales I managed to add every piece with the scales still reading 0.0g. Removing all the pieces in one go then showed minus 4.6g. If they were added quickly, no problem. But the more care you take and the slower you go, the more the bug in the scales' logic gets you. I must get around to getting my money back for the faulty scales... Regards, Jeremy Jeremy Davey Europa Monowheel 537M G-EZZA Tail done Standard XS wings awaiting mods and closing CM ready for installation in fuse (with airbrakes fittings), but holding off while I do a load of small jobs first 1100 build hours to date Intended fit: Rotax 914 turbo, Airmaster CS fully-feathering prop Lots of lights, buttons, switches, gizmos, and alarms -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of Paul Sweeting Subject: RE: Europa-List: Faulty scales --> Europa-List message posted by: Paul Sweeting Hi Jez, Very intresting - especially as I decided to purchase the My-weigh i500 with 500g capacity and .1g resoution, but its out of stock at right on scales http://www.rightonscales.co.uk/i500.htm, probably cos its 20 cheaper here at 55 than elsewhere . So therefore are you inferring that 0.1g is too low a resolution or specifically the mechanism of the scales is at fault, i.e some scales react this way whilst others do not?? Don't tell me to be assured of the correct accuracy, a balance with a lot higher resolution at a lot more cost is required... Cheers Paul.. -----Original Message----- From: Jeremy Davey [mailto:jeremycrdavey@btinternet.com] Subject: Europa-List: Faulty scales --> Europa-List message posted by: "Jeremy Davey" You may remember a thread some weeks ago started by Ron Parigoris about problems with digital scales that ignored any very small, very slow increments in weight? His test involved weighing a piece of Letter paper, then tearing it up and reweighing it, putting the pieces on very slowly. After a long search for a piece of Letter-sized paper to undertake the test (we use A4 over here) I tried it and, to my surprise, my scales failed! Now this was potentially a serious problem. I measure Ampreg 20 by weighing a pre-decided weight of resin, then adding hardener with a syringe, slowing to a drop at a time at the end. I'd often found that the last 0.5g or so (my scales have 1 decimal place) took a lot more drops of hardener than expected. Now I knew why! Fortunately for me I had discovered a few days previously that a friend in the village is a representative for a well-known laboratory scales company. I'd had problems reading my scales from some angles ever since I tried to wipe off some drops of resin/hardener with an acetone-soaked piece of paper towel (D'oh!!) and got a semi-opaque screen. He'd offered me a redundant sample from his large stock. With my new scales, the sort that have a spirit bubble and are accurate to 0.001g, I found that a drop of hardener weighs 0.03 to 0.05g. So what was the worst-case scenario? My best guess was that in the worst cases I'd added 10 extra drops, making the mix with 0.5g excess hardener at most. The smallest mixes I'd made were 40.0g resin + 10.0g hardener in order to keep the proportions within the accuracy (!!) of the scales. So these cases could be up to 5% excess hardener. I checked with a number of people for an opinion: my inspector, the Europa Factory, Dr. Bill Brooks of Scrapheap Challenge and Pegasus Aviation fame (a top bloke!). No-one knew for sure if I'd have a problem - and so far I'd done the tail, ailerons, flaps, XS wings and Cockpit module. I didn't want to ask SP Systems because I feared the litigation-aware response of 'if the ratio is wrong, you must redo everything'. Bill's suggestion was to call SP Systems, and he did have a point, so I rang Martin Armstrong in their product support (who I knew was excellent from previous experience with another question). To cut a long story short, Martin suggested the eminently practical idea of making up a deliberately worst-case-scenario batch of epoxy using my old scales and usual technique, cure it for three days, then send it to them for testing. The results were most interesting, and I'm in the clear - the sample was strong enough (PLEASE DO NOT TREAT THIS AS AN EXCUSE TO BE LESS METICULOUS IN YOUR EPOXY RATIOS!!). Strangely enough the sample gave indications of being cured at 50C - I hadn't done this (I heat the workshop to a consistent 22-24C) so I assume the striking postal workers must have left it over their brazier for a few days. I wanted to tell this story in order to encourage people to check their scales for the issue, and also to publicly thank SP Systems for the high quality of their product support. I was a very worried chap for a while. Once again I am glad I chose the kit I did, and that the various suppliers of parts are fully behind their products. Regards, Jeremy Jeremy Davey Europa Monowheel 537M G-EZZA Tail done Standard XS wings awaiting mods and closing CM ready for installation in fuse (with airbrakes fittings) 1100 build hours to date Intended fit: Rotax 914 turbo, Airmaster CS fully-feathering prop Lots of lights, buttons, switches, gizmos, and alarms The contents of this email and any attachments are sent for the personal attention of the addressee(s) only and may be confidential. If you are not the intended addressee, any use, disclosure or copying of this email and any attachments is unauthorised - please notify the sender by return and delete the message. Any representations or commitments expressed in this email are subject to contract. ntl Group Limited ________________________________ Message 6 _____________________________________ Time: 02:17:19 PM PST US From: "Jeremy Davey" Subject: RE: Europa-List: Faulty scales --> Europa-List message posted by: "Jeremy Davey" No - to do this right you should remove item, add or subtract, then replace. That should circumvent the problem, if you have it, but it will take more time. I was just lucky getting a free set of 0.001g accuracy scales as a replacement. No need identified there to take the long-winded process of removal and replacement. Regards, Jeremy Jeremy Davey Europa Monowheel 537M G-EZZA Tail done Standard XS wings awaiting mods and closing CM ready for installation in fuse (with airbrakes fittings), but holding off while I do a load of small jobs first 1100 build hours to date Intended fit: Rotax 914 turbo, Airmaster CS fully-feathering prop Lots of lights, buttons, switches, gizmos, and alarms -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of Paul Sweeting Subject: RE: Europa-List: Faulty scales --> Europa-List message posted by: Paul Sweeting But do now recall in my chemistry days being taught to always take the item off and then place back on the balance after addition or subtraction.. So the correct method to overcome this would be to add a drop or two, then take cup off balance and place back on, before adding more?? Cheers Paul.. p.s surely you mean ISO A4 not A4..... i.e 297mm X 210mm not 11.?" x 8.?" - how do I know the difference, lots of very expensive pre-printed cheques that didnt quite line up........ -----Original Message----- From: Jeremy Davey [mailto:jeremycrdavey@btinternet.com] Subject: Europa-List: Faulty scales --> Europa-List message posted by: "Jeremy Davey" You may remember a thread some weeks ago started by Ron Parigoris about problems with digital scales that ignored any very small, very slow increments in weight? His test involved weighing a piece of Letter paper, then tearing it up and reweighing it, putting the pieces on very slowly. After a long search for a piece of Letter-sized paper to undertake the test (we use A4 over here) I tried it and, to my surprise, my scales failed! The contents of this email and any attachments are sent for the personal attention of the addressee(s) only and may be confidential. If you are not the intended addressee, any use, disclosure or copying of this email and any attachments is unauthorised - please notify the sender by return and delete the message. Any representations or commitments expressed in this email are subject to contract. ntl Group Limited ________________________________ Message 7 _____________________________________ Time: 10:30:39 PM PST US From: "William Mills" Subject: Re: Europa-List: UK Weekday Fly-in --> Europa-List message posted by: "William Mills" Hello All, Weather is still looking OK for Thursday and Friday is looking OK for a fall-back if necessary. Four Europas comming so far (not including those based at Sleap). Any advance on four? Best wishes, William ________________________________ Message 8 _____________________________________ Time: 10:43:11 PM PST US From: Matt Dralle Subject: Europa-List: Last Minute...? --> Europa-List message posted by: Matt Dralle Dear Listers, First, I would like to thank everyone that has so graciously already made a Contribution to support the Email Lists this year!! Thank you! That being said, I'm hoping that everyone else is just waiting until the last minute to make their Contribution... The percentage of List members making a Contribution is well below last year at this time. Was it something I said...? :-) There's only a few more days left in this year's Fund Raiser; please help support the continued operation and upgrade of these Lists by making a Contribution today. You might look at it this way; surly the Lists are as entertaining as a typical magazine subscription - maybe more so because you can actually make your personal opinion known as well as ask questions of the "experts"! A year's subscription to Kitplanes, for example, is $30 -- and you only get it once a month! You can get nuggets of goodness from the List almost every day as well as on-line search 14 year's of Archives! Your Lists subscription is certainly worth a similar amount, isn't it?! :-) Won't you please make your Contribution today! http://www.matronics.com/contribution Thank you for all your support! Matt Dralle Email List Administrator Matt G Dralle | Matronics | PO Box 347 | Livermore | CA | 94551 925-606-1001 V | 925-606-6281 F | dralle@matronics.com Email http://www.matronics.com/ WWW | Featuring Products For Aircraft do not archive