Here is a list of all the postings Pete Rimmer has made in our forums. Click on a thread name to jump to the thread.
|Thread: Gear Hobbing computations assistance requested|
Joe if you get a 35dp hob it will come very close indeed to your 90 thou pitch (It's one thou per pitch different). Then you can turn a proper acme screw to drive it.
What are you doing about removing backlash?
|Thread: Mounting a Mitutoyo dial gauge|
Put the mag mount on the sliding strip with the gauge down low next to the base. Angle the tip down if you like - it will over-read somewhat but it will yell you where the problem lies.
Another thing you could do is make a plain back and swap it out temporarily, Usually, they are just disc of plain metal.
|Thread: Eagle Surface grinder - who here uses one?|
On my machine the outer races are held tight in the housing by the front cover. The inner races are clamped against the shoulder on the spindle by the spindle nut and wheel hub. Pre-load is whatever is inherent to the bearing set. It's not perfect, but it's 'okay'.
If I get a chance I'll pull it out and take some pics for you.
|Thread: Collet runout. Is this normal|
That taper is running out from the body. The OD, thread, face and taper should have been machined on one operation. That one certainly has not, you can see it in the face chamfer. Most likely it was turned and threaded them moved to another machine for the taper to be turned or ground.
First thing I would do is blue up the rear mounting face to make sure it's flat and has no raised burrs around the bolt holes. Then I'd mount the chuck on the backplate and if it's hardened take a PCD insert and turn the taper. If it's un-hardened I'd use carbide.
To set up for turning, use your DTI on the inside face at the point where the cutting tip will be. Watch the dial as you turn the spindle and mark the point on the taper where the dial is mid-swing. This will be the closest you can get to the true collet angle. Now swing your compound round to the taper angle and run the DTI in the taper. Adjust the compound until you can run the DTI up and down the taper with no swing. Make sure your gibs are well adjusted and check it again. Now just paint the taper with a marker pen and turn it true until the pen is all removed. Remove the minimum required and remember that when cutting a taper this way the centre height of the tool is critical.
You might have to face and chamfer the front edge when you're done to make sure the nut doesn''t bottom out.
|Thread: What inner spacer?|
You don't, hence why you leave one bearing floating. Just like the rear spindle bearing on many lathes.
If the roller is a plastic like nylon it'll have 2-4x the expansion rate of aluminium so it's just not practical.
Any metal tube would be fine for the spacer the main consideration is that the ends be as parallel as you can possibly make them. One bearing pocket should be a press fit , depth is the width of the bearing and fit this bearing first. The other pocket should be a light press or sliding fit and deep enough so that the inner race seats agains the spacer before the outer race bottoms out in the pocket, thus avoiding unwanted pre-load through the race. Press the second bearing on via the inner race and if you can, put an axle through the whole assembly for pressing to avoid the spacer tube being cocked whilst pressing.
Edited By Pete Rimmer on 29/01/2021 17:41:45
|Thread: Machine corrosion protection|
Paul it all depends on the conditions in your workshop, and outside. I have a good amount of bare cast iron in my workshop and I don't use any surface protection at all becuse the temperature remains fairly stable. If I had an uninsulated roof I expect that I would be in a constant battle with rust.
|Thread: Swinden Vice Problem|
Sounds like they have stretched the thread but I've no idea how as they clamp so well it should not be necessary. Probably using it as a press.
They are pretty easy to dismantle. Strip it down and inspect the thread.
|Thread: What machine tools are these?|
The orange device looks like a compound rapid indexer. Pull the lever and you can turn the table one notch to index again. There may be several slotted or drilled plates nearby where it was stored, to swap out for different indexing options.
|Thread: ML7 left to run for 72hrs accidentally - what to check?|
I would not worry overly much. If any of the bearings had suffered lubrication failure you would have come back to a seized spindle or smouldering mess.
All I'd expect is a little bit extra normal wear. Not so much of that either since plain bearings are happier once warmed up a bit.
|Thread: Cracked motor mounting plate|
I would span that crack with a piece of mild stel plate and some screws or bolts. If I was absolutely hell-bent on welding it rather than plating it with a doubler I would either silver solder or tig braze it.
|Thread: Lathe Chuck backplate|
I have never worried about the register being any thicker than is required to register. Come to think of it, I rarely bother to make the register a snug fit. Perhaps on a 4-jaw but not on a 3-jaw. I like the facility to adjust the part a few thou if required.
My 8" TOS everyday chuck has no register at all.
|Thread: Motorcycle General Discussion|
Yep, I've both wedled the starter nose bolt lug and repaired the ring gear on one of mine. The ring gear teeth were missing about 1/3 of the tops in a couple of places so I carefully mig-welded the tops of the teeth, turned the OD then dressed a grinding wheel to the tooth form and ground them back into shape.
Edited By Pete Rimmer on 21/01/2021 00:20:19
Is that because 130mph was about all any bike fitted with telelever could ever manage?
I'll agree about the handling though I'm on my third tele-lever bike.
No it ain't
This item is out of stock
|Thread: Chuck fitment to dividing head|
You could remove the spindle from the dividing head and single-point the thread, so long as it's not hardened.
Offer the dividing head spindle thread up to the South bend spindle thread. If the pitch is the same then the threadform must be different. Get a 1.5" - 8 TPI UNS die and run it down the thread on the dividing head, then your chucks will fit, and so will any Whitworth ones.
|Thread: Myford ML7 4 way tool holder|
Beware if you skim too much off the base the tool support can bend down when you clamp the tools. I once had a toolpost where this had occurred.
|Thread: Spur gear help.|
Those are 10DP gears, but you don't have to use 10DP, you could use 20DP (myford) gears and double the tooth count, or any other DP that will achieve the 2.40" centre distance.
|Thread: Hardinge HLV-H|
The top slide locking cam breaks because the top slide base is prone to becoming bowed which causes unwanted rotation of the slide under load so it requires more and more clamping until the cam bolt shears. Ask your operator if this has been the case? This will require scraping of the top slide, and a new cam bolt made, as I have done on mine.
Feed not working I take it is the electrical feed to the carriage from the tailstock control? That would need diagnosing as would the feed selection knob (i.e. is it just the knob or the selector behind). Neither should pose too much of a problem to a competent person.
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