Here is a list of all the postings Matt Stevens 1 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Polishing Castings|
Ok....maybe you are right and I need to start with a more coarse grit. ..... I just wondered if there was another technique that was perhaps more effective (hence the comment about a polishing wheel on a dremel or bench grinder)
Now that I have started to make bigger parts - i.e. a 7" flywheel, I am finding that using various grit papers to polish becomes a magnitude harder! I would like to get the flywheel to a mirror finish but I am finding using 600-grit is really just polishing the edges and not particularly removing the machine marks.
Does anyone have any hints and tips? For example - what about using a buffing wheel and polish sticks using a grinder?
|Thread: To overbore or not to overbore...that is the question!|
Thanks for the responses....I think I had every possible answer/option there! I guess what it tells me is that it shouldn't really matter if one cylinder is different to the other. Given that, I will likely make the second cylinder according to drawing at 1"....continue the model and if needbe, I can always sleeve the first cylinder later.
In a former post, i showed a problem with a cylinder for a Stuart Victoria that i bored out of true. I was able to correct this by over boring but the bore is now 1.1" instead of 1" and the remaining 'meat' on the cylinder walls is also about 100 thou which i think should be ok.
Now - i happened to purchase another Victoria single and will therefore make the two singles into a twin engine.
Question is - should i bore the second cylinder to drawing at 1" or should i deliberately overbore this also to 1.1" to match the other side? Does it matter if there is a difference from one side to the other on this size of engine?
Another option is i could try sleeving the first cylinder and then re-boring to the correct size. If i did this, what material should i use as a sleeve as i don't want different expansion rates cracking the cylinder.
|Thread: Correcting an off bored cylinder|
Thankyou everyone for your comments.
Buying a new casting is an option, but i am in Canada and by the time i have paid for the part/shipment/broker fees/tax etc it will be equivalent to 50 quid. And, i have nothing to loose by trying to correct it....if i mess it up further, there is nothing lost
I see there are a number of ways to do this and correct the problem.....actually part of my problem is equipment i have available. For example - i do not have a faceplate nor true 90 degree angle bracket....perhaps i should invest!
One approach i have read and like the idea of is using a faceplate and a Keats angle plate. This looks a very easy way to correct the problem with easy adjustability whilst ensuring a true parallel setup......the other approach i thought of was to use a tube drilled and tapped with 3 screws at each end. The part could than be clamped and adjusted in the tube. The tube can then be fitted into the chuck and easily checked with a DTI.
Anyway - thanks for all the ideas, i will let you know how i get on!
I have a Stuart Victoria cylinder that i bored off center and the end flanges are faced to match....i want to correct it and i think there just about enough meat to bore out bigger and increase the piston size.
Question is - how best to set it up in the 4-jaw squarely in order to make the correction....i effectively have no reference face.
|Thread: Stuart D10 reversing gear timing - eccentrics|
So just as feedback....i set the other side at 180 degrees out after playing around with the timing, and i believe that 180 degrees is correct which in my head makes sense anyway.....i'd like to understand where this 120 degree theory come from!
I just hope i can see the first side again using heat other wise i will have to make new Eccentrics
So I am in the process of finishing a Stephenson's reversing gear set (from Stuart) for my D10.
Generally speaking I thinking my machining is pretty accurate and I have the eccentrics pinned at 120 degrees apart per the instruction. I did this by marking the first eccentric out using trigonometry, drilling, then placing this against the second eccentric (flipped over)to drill that one.
Anyway - when it comes to setting up the timing, I have adjusted the eccentric strap to expansion link rods such that I get equal travel in both the forward and reverse settings.....next I have set the eccentrics such that the valve timing is correct when say in the forward direction - that is - just before TDC, the top port starts to open to cushion the piston travel and likewise at BDC it is also correct (ish/valve may need filing slightly to get it totally accurate).....anyway, now when I switch to reverse and turn the crank over in the opposite direction, the timing looks to be way off....like about 60-70 degrees off! Why?
I can only conclude that the eccentrics are not set correctly. I can understand a couple of degrees in accuracy, but so much?!?! I have seen the principle of sliding eccentrics such that you can fine tune, but is this practical on a D10 given the size? Am I going to have to make new eccentrics as my existing ones are nicely pinned together with red Loctite. Maybe heat can separate them?
Any other advice?
|Thread: Stuart Model delivery|
Good plan...I will ask. And its the Victoria...
...yeah....but 6 months?!
Is anyone else finding that castings delivered from Stuart models are significantly delayed? I have been trying to order a set of castings now for 6 months and they are just not available yet?
Do they have foundry problems?
|Thread: Cheap 3 phase inverters.|
So I would have to recommend the Siemens G110 inverter as a cheap VFD, or if you want vector control then go for a Siemens MM440.
Both these inverters are made at Siemens Congleton in the UK where I worked int he R&D department for a good ~13 years. Hi quality and tick all the boxes mentioned by Dave above.
They will not be as cheap as some of the Chinese stuff....but then you get what you pay for. Same scenario with Lathes and anything else....
|Thread: South Bend Lathe - Chuck and collets|
Thanks for all the comments guys....
For the record, I am based in Ontario Canada.
I have googled the spaced idea - as usual, so simple once someone has pointed it out to you! I will check the runout of my chuck and see how much is to be gained by grinding. I would have to make a fixture for a start to hold my dremel!.
For the collets - again the Drawbar seems the sensible way to go. As Mark Smith pointed out he has a 9a model, that will be the same as my 9c....so I am confident to say I will likely need 3C collets I guess.
The ER collet solution looks interesting, but I guess this route is also more expensive?!
Perhaps I will keep an eye open for a 3C collet set on ebay!
So I have a 1939 Model C South Bend. My 3-jaw chuck is not exactly the most accurate and I wonder the best way to improve this.....I have bored it out slightly, but the jaws were not clamped in anyway - mainly because the jaws are hardened and therefore near impossible to drill to fit a clamp to.
Buying a new chuck is very expensive....so maybe I can just change the jaws? Is there anything special I need to be aware of when searching for new jaws?
Collets - My mill has R8 style collets and so I guess it would be great if I could re-use those on my lathe somehow. I have a feeling the lathe might be M3 (would need to check). Has anyone made any converter? Any hints/tips?
I guess I would also need something to screw onto the headstock to pull in the collet?
|Thread: Stopping castings rusting|
my only thought about using any type of oil is the smell..... I am hoping to have my Stuart D10 proudly displayed somewhere around the house and want to avoid the wife telling me it has to go away because it smells oily!!!
But thanks for the feedback....
So another beginner question you might say....
When you have finished a model, protection from rusting is normally in the form of oiling for the inside and the graphite yarn on pistons will assist with this. For the outside, paint is normally the order of the day....that is, unless its a surface that is polished and by design is to be free from paint and/or oil. E.G. a Flywheel.
So....how do you prevent those shiny non coated parts like flywheels, valve chests and covers from rusting?
Interested to hear your views.
|Thread: Drilling brass|
....but of course it really means you need a set of drills for brass independent to drills for other materials. Unless someone likes sharpening drills every 5 minutes!
So I was making some brass bearings at the weekend, drilling and reaming for the crankshaft....
My debate was - do I drill/ream dry or with some cutting fluid?
Using cutting fluid I found that the drill will clog easily and then it will scream away. So my thoughts was dry was better.
Comments? (I know...I am still learning)
|Thread: Loctite for drilling|
...so just for feedback, I used some scotch double sided tape....very thin, not overly tacky but sufficient to hold the parts together for drilling. The holes where only 2.3mm anyway so not much turning force - but worked out well.!
Of course this strategy would not work on a rough casting, only on machined finishes.
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