Here is a list of all the postings Gerhard Novak has made in our forums. Click on a thread name to jump to the thread.
|Thread: What to do when you lose something|
I can play in that song, just bought ball link pliers and was sure my son took mine for his model helis, so when the new one arrived I put it where it should be - and found the old one... Probably I need spec-savers...
|Thread: Shipping to the EU - beware!|
I am pretty sure some of the 'import charges' are going direct into the pockets of the forwarding companies, using every excuse to make money. I also can see now 'handling charges' which in some cases are 3 times the price of the product I purchased. I wonder if there is a real background for all of them or if Brexit is used as an excuse to milk some customers...
|Thread: Small saw. Proxxon or something else|
Yes, this is the machine. For me it is mainly to cut of materials from bars, of course if you want cut from flat material or sheet material it is not the one.
Have you ever considered cutting by an oxygen cutter? (plasma cutter)
I think a thin cutting disc should be the easiest think to do.
I own a Proxxon FKS (the older sister of the FET) and I think it is one of the most useful tools in the workshop. It is true you cannot cut steel on this machine, but if it comes to brass or aluminium it is performing well. especially with the finer TCT blade (36 teeth) As said on the label you shouldn't push too hard as 200W is not too much power. Because of its precision and its very clean cuts I used this saw for all kinds of purposes, not only for making models. For example I did cut all my wood flooring on this saw.
What do I use for steel? An ordinary chop saw with a standard "cut it all" blade. The machine is an Evolution R210SMS (Screwfix). Blade diameter is 210mm, power is 1500W. Blade cost is approximately 20£ on the internet. I found some cheaper replacement blades from Erbauer for 12£, they were as good if not better, but they disappeared from the market. Probably Kingfisher was not happy and wants to sell their expensive blades (30£ at Screwfix).
40mm mild steel is not a problem at all. And you can cut wood after that and the blade will still perform. For me this was the decision not to buy an expensive metal only saw. If I can use the chop saw, even with a blade change from time to time, I can cut for a long time and be still much cheaper.
Safety advice: Clamp the work piece safely. There will be very hot metal chips flying around which can not only burn your skin but may also be a fire risk. Use proper goggles.
|Thread: ME Boiler|
" There is one slightly annoying issue, in that once the safety valve has opened, it never seems to quite close completely again unless the pressure has dropped by quite a bit, sometimes as low as 40psi. Although just a gentle press on the stem seems to fix it until the next time it opens. "
See if you can do a "pop" valve. They have a kind of piston above the valve which helps to open safely and when it closes the pressure was that for the larger piston, so the smaller valve will pressed firmly into its seat. I tried one, probably my precision wasn't good enough. I worked most of the times but not always. (Well it opened but jamed when it should close...)
|Thread: A monoblock twin study|
I have actually seen this design also for other model boat engines. By the way - I have a swimming bath tub in my office - my late fathers masterpiece. The Reliant. If you ever have been in the Maritime museum in Greenwich you may have seen one of the engines (full scale) and a model. My dad built this years ago, and after he passed away I drove to Vienna to get it over. Didn't want to post it, you never know what arrives.
It would be a project and a half to put the two twins into this boat. Probably it is too small for that, but it could take one horizontal twin like for instance the Stuart Score. Length of the model boat is 40" - same as the model in the museum. Of course I have also a replica of the Greenwich clock on the wall...
|Thread: Looking to learn CAD|
I would like join the "free CAD hymne". I am using QCAD, for the simple reason that a guy who is doing custom laser cutting wanted this format. QCAD is mainly a 2D program, but 3D is possible. I think you need to have a good understanding of 2D before going into a 3rd dimension. The free version has of course some limits, one is for instance printing. It doesn't do a print over multiple pages. But you can print a part of your drawing. A feature which is also not working is the single line detection. If you draw exact (what you shoud do with a CAD software) you will not notice if you went twice over a part as long as you are using the same line width. This is not a problem if you just draw something, but it is a problem for laser cutting. As I said the software was free, but I purchased a book (QCAD - an introduction to computer- aided design by Andrew Mustun). The book is a must to get familiar with the software. It allows using the cursor interactiv but also relative or absolute coordinates and if you are really good you could work from the comand line only... See two examples: The railway station of Brackley - rear view. (You may say there is no railway in Brackley - right, but there was - the Great Central Main Line. The station is still there, just in front of the old Racing Point F1 team building. I built this station in 7mm scale and had all window frames laser cut.)
A second example is the machine I am currently working on (well, if I do not work for money or upgrade the garden to my wifes likings...).This will be very small, as I used a function to print all on one A4 page. But as said before, you can print whatever section you want in any scale you want. Have fun in learning CAD!
Edited By Gerhard Novak on 15/04/2021 14:39:12
Edited By Gerhard Novak on 15/04/2021 14:43:18
Edited By Gerhard Novak on 15/04/2021 14:47:26
|Thread: A monoblock twin study|
As Jim said this setup allows self starting from any position. As you have double acting pistons (minimum on my model) you divide the power into 4 equal parts, with a peak every 90 degrees. This gives you the smoothest running possible. Of course, the power is not completely equal between the piston going up or down, as during the "up" cicle you lose the area of the piston rod and you may have some loss due to the gland packing of the rod.
But let's leave this aside, I am happy if the machine runs!
Jim, lovely machine! You went for a reversing valve - am I right?
I am not sure what to do - I would like to have a Stephenson valve gear, but there is not too much space available. Anyway, I can make that later, I just need to leave enough vertical space for it.
After some break a sign of life. A crankshaft has arrived. The first one I made I killed during milling, as it flexed and the milling cutter caught deep into it. All bent, cutter broken.
I improved the clamping by making exact matching packing pieces to grab the shaft in a normal machine vice, I had it in a turning table during my first attempt.
I also invested into a cheap DRO for the other 2 axis of my Sieg SX2, all 3 axis together under 100£
Here the second attempt, still not perfect but it shoud do it.
Unbelievable how much fine metal pieces and/or dust are on the part. You hardly see it with the naked eye, but the photo is cruel. Everything comes to the surface....
Edited By Gerhard Novak on 13/04/2021 18:36:29
|Thread: Parting Tool Holder|
Nice work, but I think you will miss the height adjustment. may be you could have a shim below if needed.
I like the touch with the producers name and year. Is it punched or engraved?
|Thread: Which lathe to purchase|
I totally agree to what you wrote, and also I own a Chinese lathe (DB8) and it is for sure much more accurate than a 60 years old model,and on top of being worn out it is also imperial....
I have just recently purchased a Chester DB8vs and I am impressed with the precision. The chucks runs pretty true, much better than the one on my Emco compact 5 I had before (for 38 years). The jib strips were all set up, no adjusting necessary. Little backlash in the handwheels. So it was just cleaning. Reading several comments of people who had to rip half the machine apart to set it up properly - not at all necessary here. I start liking this machine. The bed is pretty stiff, parting steel no problem. There is plenty of power, but the motor is noisy. It is not a brushless synchrone motor.
By the way, after my positive critisism (except the noise, but I am even getting used to it) of the DB8vs I have to say I am not born in China but in Austria - the land of Emco.
Price: you will need a few extras, even the accessories coming with the machine are plenty (fixed and travelling steady, independent 4 jaw chuck, self centering 3 jaw chuck, centers for spindle and tail stock and even some carbide tipped tools.
You will need a live center for the tailstock, a drill chuck for the tailstock, and if you want to attack smaller stuff also a collet holder and collets (lucky me, I have a mill and I found a collet holder which uses the same size - this saves some money). I also purchased a quick change toolpost and some holders as I am spoiled from my old machine, which had also one. So whatever you pay, consider a couple of hundrets for accessories.
And: look for a stable workbench. I use a good quality kitchen cabinett which is strong enough. Think also about transport of the lathe to its final position. It ways 110kg net, in the box with the accessories it is 130kg.
Edited By Gerhard Novak on 24/03/2021 20:39:08
|Thread: Lathe annoying 50Hz hum|
I should have read this thread before purchasing my lathe. I can confirm the noise it makes is disturbing. Exactly as discribed in this thread... I have an SX2 mill standing next to the lathe, absolutely silent runner!
|Thread: Moving warco gh universal into workshop|
Well 320 kg is a challenge. I recived yesterday my DB8VS, I have the advantage of a stepless garden path to my shed and could convince the driver to move the box on his pallet trolley down the garden. So step one was easily done. Step 2 was a bit harder. I removed everything heavy like chuck and tailstock and then it was muscle power. My son and I grabbed the machine and lifted it up to the workbench. After my weight removal action it had probably 100kg. Felt heavy enough for me even I was on the light side (tailstock side).
and finally reasonable cleaned and screwed on in its final position.
|Thread: Two or three axis DRO|
correct, I need to raise the depth stop otherwise I cannot use it. But as said above, the display is just fixed by 2 permanent magnets, so no problem there. The printed column scale is gone, as a) it was in the way and b) I used some of the fixing holes to fix the new, electronic scale.
Ron, thanks for the hint, but I think this can be fixed with some transparent plastic sleeve
|Thread: What Did You Do Today 2021|
Installed a DRO for drilling depth measurement to my SX2. Was straight forward and I am happy I did it. The crankshaft I had started to look at has to wait, as I have sold my lathe. Went in less than half a day. Of course I am asking myself if I didn't ask enough for it, on the other hand the new owner should enjoy it. I am now "latheless" until the 25th of March. No fear, my wife can easily fill the spare time with DIY projects...
Edited By Gerhard Novak on 15/03/2021 21:20:39
|Thread: Two or three axis DRO|
Back to my single axis z-axis problem on the SX2. This is what you see when you in front of the machine
The depth indicator is well hidden behind the motor control. Lets have a closer look.
I have to say I am not acrobatic enough to read that while lowering the drill (not such a problem when milling, as you normally use the fine feed)
Solution: A cheap, battery powered single axis DRO. Now already in position. Using the screws which held the millimeter scale I need only one extra hole to fix the sensor in position. The brass strip making the connection between sensor and milling head is using the hole where the old, mechanical indicator was fixed.
This made my day, a quick fix for £30.
Edited By Gerhard Novak on 15/03/2021 20:38:16
Edited By Gerhard Novak on 15/03/2021 20:41:26
I am considering a very cheap single axis DRO for my SX2. When I use it for drilling it is practically impossible to read the drill depth as the depth indicator is on the rear left side of the machine. If you drill in a normal position you cannot see it. Of course I could use the fine feed, but if you want a hole 10mm deep you get crazy doing it with the fine feed. So M-SURE MS-278-200 is on order.
|Thread: What Did You Do Today 2021|
What did I do today? First of all I was working, as some money needs to flow into the account. Then - Well I put my lathe into the 'classifieds', but so far no piep.
At lunchtime I looked into Chester Hobbbystore and saw a DB7VS (ex showroom) including stand for £855. While I compared the technical data with the machine I am actual aiming for the offer was gone - somebody grabbed it. This didn't really make my day...
Will go in my workshop later and keep on with my old machine. Current job: make a crankshaft for my little twin study. I will build it up from 7 parts.
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