Here is a list of all the postings MalcB has made in our forums. Click on a thread name to jump to the thread.
|Thread: Piston Clearance ( Economy Engine )|
Thanks people all the info needed, stay safe.
My kit with the bit of progress so far below. Gotta face liner to length, finish bore and hone. Will bring up bore to suit ring gapping when aiming for dead size and if it works out then machine piston to suit.
Jason - I do have in mind to do additions on piston to supplement oil transfer and thanks.
Henry - Not starting cylinder head yet and will order valve material then, but may well be 316 but will research a bit.
Henry, if you havnt already done so, do a search on here for Economy Engine and you should come to Nicks build on one. I would bookmark it on your device.
Very informative and quality workmanship, it has set the benchmark for me. Also good input from Jason on it as well.
Jason - Many thanks for your advice I was hoping you would come along having such a wealth of information.
For info I will try and get a pic on today of progress so far, waiting for an Asda delivery so fingers crossed.
Edited By MalcB on 26/03/2020 10:12:35
Edited By MalcB on 26/03/2020 10:13:05
Its a half scale open crank hit and miss engine. There are a couple of builds listed on here but not the info i seek. I am following the one that Nick built on here ( yellow painted ) as a reference.. mine is the std alloy casting version with cast iron liner and cyl head,
Have done the twin flywheels, machined all the main body casting, manufactured the crankshaft, con rod, main bearings and con rod bearings, machined the main hopper/cylinder casting ready for the cylinder liner. Have finish machined OD on cylinder liner, rough bored thru’ 1.5mm undersize and ready to finish bore and hone.
When the piston assembly is complete my next stage is the gear train assembly.
|Thread: Has something happened between SKY and Yahoo mail?|
Yes it happened to me about 3 weeks ago.
Could log in to portal but not on Outlook, iphone or Ipad.
It was a pain getting them all going again, from memory I had to get a code, you need to google this.
|Thread: Piston Clearance ( Economy Engine )|
I am at the stage of boring the CI liner. The nominal design size is 42mm diameter.I have the rings supplied in the kit. I am intending aiming as close as possible to dead size after boring and honing.
Piston body is aluminium so what clearance twixt piston body and liner should i be looking at please?
Also when boring/honing the liner and trying rings in what sort of gap should i be looking at in the rings, I would guess at say 0.06mm min to 0.16mm max or is this too tight?
|Thread: What to do,what to do.|
I have an RDG SC 4 jaw for my Harrison M300.
As others have said its a luxury unless you have an abundance of chucks and frequent need for square bar stock.
I have 3 x 3 jaws, 3 x ind 4 jaws and 2 x collet set ups ( 1 x ER40 and 1 x Pratt ) all gained at various times etc.
They do make a good backup for round stock to the 3 jaw and the RDG one i have is excellent on running true.
My advice ( again as others mention ) is to save further for a good collet setup first.
|Thread: Large scale hit and miss engine castings|
Great build by Nick_G of the Economy Hit and Miss by Engineers Emporium.
|Thread: Collet Chuck or not ?|
If you cant run to an immediate collet setup then use a 4 jaw and set true.
Unfortunately shelling out on a new half decent collet setup goes against the grain when the cost could be on the way to financing a used milling machine package.
As others have said, once true in a chuck you have the lesser rigidity in a lathe to deal with. Make sure all slideway jib strips have any unwanted play taken up. If you can, lock any slideways up that are not being used. If your compound slide is still fitted, minimise any overhang.
Small cutters also demand much higher speeds than many lathes can achieve, so watch your max chuck rpm and take it easy.
|Thread: Lathe info|
I had one very similar and a good lathe indeed.
Pretty sure Its a very early ( 1940/50,s Colchester Master ).
You may find details on Lathes.co.uk or google early images.
Edited By MalcB on 18/03/2019 13:12:30
|Thread: Toolroom lathe?|
Andy, what Dave has just said is spot on.
I served my time and spent early years on toolroom lathes such as Harginge, Monarch, DSG, Lorch to name but a few. In those days very few lathes had DRO fitted so good accurate dials etc were a bonus and in the main expectation
When in good condition they ooze with quality and are a joy to use. They do achieve very high precision. As they wear then not so much. They however have their limitations in that not many have gap beds, tailstocks on lathes such as Hardinge and very heavy, the swing over bed is not usually great.
I thought about getting my own Hardinge as I loved them along with the Monarcs, but in the end settled for a good used example of the Harrisom M300. I am so glad i did as with or without the DRO I fitted it has great capacity, facilitated with the removable gap bed, has a great speed range supplented with the inverter if required ( but not act necessary ). It is as accurate as ever i would want.
Edited By MalcB on 18/03/2019 11:43:20
Edited By MalcB on 18/03/2019 11:57:51
|Thread: Manchester Model Engineer Exhibition 2019|
Being very local to me and enjoying the 2017 show i Watch with interest their web site.
At the moment they still list the show as Planned for 23rd/24th Feb 2019.
When I check the Queen Elizebeth Hall web site the event is not yet listed.
Does anybody have any further information on the status of this show pls?
|Thread: Does 4 jaw chuck quality matter|
You will also see a lot of independant 4 jaw chucks with significant cracks in the screws around the chuck key locations because of these " tube users ".
|Thread: First Milling Machine|
I personally would prefer a turret mill like the Chester or Warco 626 sized VMC's over a bench mill because of the added versatility they can offer.
Mines an early Chester 626 picked up 2nd hand with 3 x axis DRO and single axis power feed.
Warco have upped their game on their VMC by offering a variable speed jobby version which may be of interest.
If you can financially run to it go for DRO/ power feed options to kick off with, however if not and you are handy you can upgrade later yourself with better systems.
|Thread: Fitting Inverter Drive to Harrison M300 Lathe|
Thanks Jon, but mines already sorted. I have included for additional switching in my circuitry to engage or disengage the chuck guard switch as needed. I was asking how Ken had dealt with it on his similar machine as dont think it was shown in MEW article.
Yes, i understand exactly about the 8" heavy Pratt 4 jaw as I got one with my lathe. I did however manage to get a slim bodied 8" Pratt 4 jaw ( almost unused ) at a very good price which also has much narrower jaws. Had to D1-4 backplate mount it but its much lighter and feels a lot more sensitive. In fact its a joy to use against the industrial one which I now only use occasionally. These are well worth looking out for to use on the M300.
How did you get round the chuck guard limit switch when you have to remove the guard?
Gareth PM sent
Hi Gareth, you do not mention which type of M300 you have purchased or are purchasing.
I have the same later (2003) white model that Ken Wilson covered in the MEW no.154 -2009. These models have more extended electrical controls than the cream coloured earlier versions. There are more contactors and overload protectors to deal with.
I found Kens version really good but overly complex on the logic controls. I hence did my own circuit diagram on the CAD with a lot of help from a friend who is an electrical wizzard and got him to check it all as i progressed. All the contactors and overload protects are done and supplemented as in Kens circuit but my logic controls differ but still retain all the use of all original controls and safety features.
I do have the coolant pump in the circuit which worked when i tested it but i never use it. I use a none soluble cutting oil from a Wurth oil spray application bottle. I find this far more userfriendly to the machines slideways etc.
I use the Teco inverter which to date has been perfect. I do have an issue with the foot bar brake. It works as normal if not used too heavily but under total emergency hammer down braking it decelerates the inverter too quickly and throws an error that needs a total repower to clear. It does do the dramatic stop that may be needed. This is because it also uses break blocks on the pully alongside the inverters electrical breaking. At the moment i live with this but may be future work in progress as i dont normally use the foot brake as the saddle lever controls work very well on their own. I know the foot brakes is there if i need it in an emergency.
You do need to Joint the yahoo harrison lathe user group as there is masses of info on there on VFD,s and their application and highlighted potential problems that have been overcome. There is a user on there called Rupert Powell who has provided invaluable info and drawings, some of which I have incorporated into the logic part of my controls.
|Thread: lignum vitie bearings|
You can in fact machine oilite bearings, there are articles on the recommendations for doing this if you google.
Yes you can run the risk of burnishishing the pores but if you stick to guide lines this means fine point boring to size ( not reaming ) with a very sharp small boring tool running at a surface speed ( from memory ) of around 150-200 metres/min.
Reamers will burnish the pores
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