Here is a list of all the postings David Kenyon 2 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Any uses for an old tired lathe bed|
That's an idea , I might have a go at scraping it.
The problem with a re grind is the cost , I managed to pick up an excellent second hand bed much cheaper than a re grind
I replaced the bed on my Myford S7 a while back and the old bed has been sat under my bench ever since. Before I have my next tidy up and take it to the tip is there anything it might be useful for.
|Thread: Crucible for annealing cast iron piston rings|
Thanks John, would be useful but I can probably work it out for myself if I need too so don't spend too much time looking.
Also does the crucible have to be made out of cast iron or can I use steel
I made some piston rings for my Gypsy engine and I want to heat treat them using a crucible [Trimble method I believe].
Reading on the internet I see reference to a formula which gives the dimensions of the crucible for a given ring size, does anyone one know were I can find this formula?
|Thread: Is it bad practice to lock my Myford lathe using the slow speed lever|
Seems I might have to change my ways then , I will try and get in the habit of using
the locking pin.
Drilling a hole in the back plate to aid unscrewing sounds like a good idea, thanks.
When I remove a chuck or tighten a collet on my Myford Super 7 I lock the spindle by engaging the back gear , effectively engaging two gears to lock the spindle. I realise there is a locking pin at the back of the spindle but its just easier the way I do it.
Is this bad practice or is it normal for other Myford users.
|Thread: Brown tarnish on brass plate|
Hi , I made a Congreve clock about 4 years ago , the brass has a bright polish and coated with Renaissance wax. Its kept in a glass case.
On the brass plates I keep getting a brown mark , almost like a light rust, just in a couple of small areas. I can polish it out but it always seems to come back .
Is this caused by a bit of contamination in the brass plate itself?
|Thread: Cast iron dust , is it really that bad for lathe beds.|
Well finally finished my barrels , I was going to machine a spare but got fed up with the black mess.
May regret that decision later down the line .
Have spent the last two days cleaning my mill/lathe , to be fair the most of the dust was external and
the slideways were still clean but at least I feel better now and the machines are all readjusted .
I will give it a wipe over before I start barrel no2 then probably do a strip down when I get to no4.
I like to keep my machines clean anyway so I suppose a strip down will not do any harm.
Judging by how easy It is to machine I am guessing I have soft meehanite bar.
I have been machining a 2'' round piece of cast iron into a finned barrel for an engine I am making.
Going between lathe and mill I have managed to produce a large amount of swarf and everything is covered in black dust, including me.
Not enjoying it and I have another three to do.
Will all this dust be a problem, do I need to strip down my equipment and wash everything off when I finish barrel no4.
|Thread: Need help making a camshaft|
That's great Jason thanks , I presumed the flank had a slight radius, just curious but how do know
the flanks are flat.
Looking at the timing it shows the crank moves 240 degrees for the inlet and 260 for exhaust so that would be
120 and 130 for the camshaft . On the dials for the jig it states 130 / 140 which confuses me .
Its for a four cylinder Gypsy engine, the plans show that the cam is built up from separate parts ie. the lobes and bearings are machined then Loctite onto the shaft.
Now I understand what a camshaft does and how it operates but I have little knowledge of making one. After some research I feel making the lobes on my mill using small flat cuts with the aid of a rotary table would be the best option for me.
So I need to come up with some figures for the machining process.
The plans show just one lobe as below
|Thread: Making split bronze bearings [ silver soldering ]|
Well I tinned each half with soft solder then clamped them together and re heated.
Worked well, I managed to machine 5 bearings with little trouble although the bar did split on my third bearing
when I drilled out the centre, the drill pulled into the bronze.
I re soldered but this time put a jubilee clip around the outside until I had finished the bore .
Well thanks for the replies, certainly given me something to think about.
I was worried that the solder on the mating surfaces would compromise the final bearing size
but I see this is not the case.
I will get some solder paste and give that ago first , will let you know how it goes.
I need to saw a piece of phosphor bronze round bar in half and then solder it back together before machining to size for the split bearings.
My question is, do I put flux on the mating surfaces before clamping together or leave them clean , clamp together and then just run flux along the join.
When the piece is soldered I will need to turn the diameter down so I presume the solder will need to penetrate the join so it stays in one piece.
|Thread: What is a good quality lathe paint|
I used HMG Paints C71 enamel **LINK**
Use a good primer , I used HMG again , still looks good today.
|Thread: Line boring question|
Hi , my lathe has not got reverse so is there a way of sharpening a cutter to run in both
directions, I was thinking a single point with a rounded tip. This is so I can use a shorter
bar and reverse it to do each half as suggested in the Benz thread
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