Here is a list of all the postings Clive Brown 1 has made in our forums. Click on a thread name to jump to the thread.
|Thread: 1" Minnie oil pump problem?|
Hi Terry; "cut-off " applies to the valve movement as adjusted by the reversing lever. Full movement gives steam admission for 100% of the piston stroke, (100% cut-off). Progressively less as the lever is moved towards mid-position. My point is that since the engine won't function at small cut-offs, say 25- 30% minimum, it doesn't need lubrication for that situation.
Dunno about the Minnie, but my Allchin water pump drive is off the crankshaft. The lubricator drive is off the valve spindle so the ratchet stroke is altered by the position of the reversing lever. If the stroke were to be too small, the drive wouldn't pick up a new tooth. I can't see that being an issue as the engine won't run with the valve gear in that position anyway. As long as the pump works with the cut-off at a working position., that's OK.
|Thread: Super 7 - Best way to use ER25 Collets|
The obvious difference between the two types is that the MT holder will not allow long lengths of bar to be held through the mandrel.
I wouldn't think that either one was inherently more accurate than the other.
|Thread: What are these change gears for?|
Similar to my Boxford ME10.
|Thread: Loco hand pump casting from Reeves|
The 3/4" dimension refers to the cylinder OD. Seemingly an extraordinary design. What's wrong wth increasing the bore to 5/8", which would have given plenty of capacity IMO?
|Thread: HSS or CS taps and dies|
IMHO both hss and cs tapsof good quality are suitable for the type of ME work that I do. I have both sorts, acquired as needed but mainly cs. I believe that hss taps are usually produced by thread grinding, whereas cs taps are cut threads. Grinding does, I understand, produce a thread-form to a tighter tolerance and possibly with better relief angles to the cutting edge, so is better for high class work.
I doubt whether the red hardness of hss is often called into play, certainly not in my workshop!
That's my tuppenceworth,
Edited By Clive Brown 1 on 20/05/2019 14:26:03
|Thread: Drilling cast iron - where did I go wrong?|
|Thread: fobco drill|
My Fobco Star is as others say. The Table is clamped by a through bolt and short ball handle. The slot is closed off at the bottom. I too use a piece of tubing to get more leverage. I put this need down to 50+ years of wear causing a slight increase in clearance on the column. In use I try to minimise the number of times I move the table with an array of wood packing kept by the machine.
The head is clamped by a two-piece clamp, also shown above. It's more effective than the split clamp but there is not enough metal in the table casting to modify it to that type.
Edited By Clive Brown 1 on 16/05/2019 08:39:22
Edited By Clive Brown 1 on 16/05/2019 08:40:31
|Thread: DIY Bed Gap|
The Saab discs that I skimmed did have a minimum specified thickness for such work.
I'm not a car enthusiast but I thought that the reduced life of brake discs since the "olden days" stemmed at least in part fom the change from asbestos based maerials for the pads. This forced a change in the material spec. for the discs to a softer value.
I once wanted to skim the brake discs from a Saab 99. These wouldn't quite fit on my Boxford ME10 so I put spacers under the headstock, which turned it into a ME10.5. Job went quite well as I remember with a carbide tiped tool.
Being a Saab, these discs were quirky in that they included a drum for the separate hand-brake shoes. The working surface of these drums corroded very badly, as they didn't ever do any real work,. I could skim them with the same set-up.
|Thread: M&W Straight-Edge Set|
Thanks for all the comments. Another minor mystery solved. My piece of glass isn't marked "test-piece" as the catalogue illustration seems to suggest.
I have an ancient boxed set of Moore & Wright Toolmakers Straight-edges. M&W part no. 315. Four steel straight-edges from about 2" to 5" in length and also a length of what looks like a piece of black glass about 5" x 1" x 0.25".
Does anyone know the purpose of this "glass"?
|Thread: How much can a chuck effect finish?|
Is it a 3-jaw or a 4-jaw sc chuck? the OP hasn't said which. I ask because an inaccurate 4-jaw won't hold round stock firmly, whereas a 3-jaw will.
A separate point is that work overhang is greater with a chuck than a collet, giving more of a test for the spindle bearings
|Thread: Pendent control box for a VFD|
I bought the switches, potentiometer etc for my pendant from Inverter Drive Supermarket. They stock a complete range of components, apart from a housing, and at very modest cost.
|Thread: Mill Query, help needed|
If it's any help, I bought an imperial 3MT Warco 16B fairly recently and I'm very pleased with it so far. Not a machine for heavy milling but it seems good value. It's accurate and the general fit and finish are impressive. I don't miss a tapping function but I do have a GHT tapping tool which has much use and serves very well for accurate tap alignment. Most of my threading is BA sizes and I feel that small taps are less likely to be broken when "hand-driven"
A feature of the 16B is the relatively short quill travel, 50mm, which might be a niggle if you don't have a bench drill.
|Thread: Collet Chuck or not ?|
My experience of using a 4" 3-jaw chuck for end-mills was that it's OK if basically cutting with the end-teeth. However, if heavish cuts are taken using the side teeth, then the helical tooth shape can pull the cutter outward from the chuck. Trying to avoid this by over-tightening can be unkind to the chuck.
ER collets don't seem to suffer this and auto-lock chucks are immune of course.
|Thread: 1947 M type myford, imperial or metric ?|
Whitworth/BSF hexagon sizesare denoted by the thread diameter. Their AF dimensions generally do not match the hexagon AF sizes for either unified or metric fasteners, so using these will result in a poor fit. The appropriate spanners really need to be obtained.
Many spanners have 2 marked sizes, BSF being 1 size larger. eg 5/16" BSF is the same hexagon as 1/4Whit.
Edited By Clive Brown 1 on 24/03/2019 17:40:16
|Thread: How Are Letter / Hallmark Punches Made?|
Not helping the original question, but I seem to remember that Arnold Throp,( who put the Dore in Dore Westbury)*, was a senior figure, possibly the Boss, in Pryor Punches.
* For non-Sheffielders, Dore is where AT lived.
|Thread: Boxford Screwcutting box / Leadscrew binding|
Just to add a little to above; with the gear-train disengaged from the spindle, and the saddle and cross feeds disengaged, the input shaft of the gear-box should turn easily by hand. With the lead-screw rotating check that it isn't slightly bent. Temporarily slacking off the 2 bolts holding the R-H lead-screw support allows a bit of float if the lead-screw is binding. It's a fairly close fit through the saddle gear, which supports it.
Does the saddle easily traverse the full length of the bed by hand?
Don't try to remove the gear-box yet, but it should be possible without removing the headstock, ball-ended allen keys are a help for the 3 screws into the top of the 'box.
Edited By Clive Brown 1 on 13/03/2019 08:51:05
|Thread: Brook Cub 1/2 hp Motor - Capacitor or not?|
Some single phase motors are split phase start without a capacitor. As said, try it and see. They are at the cheaper end of the market and suffer from rather low starting torque and should not be started too frequently to avoid overheating the starting winding. Probably OK for a drill though.
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