Here is a list of all the postings HOWARDT has made in our forums. Click on a thread name to jump to the thread.
|Thread: Help and advice on a drill bit for hardened steel|
You say a hardened stud, how hard. I would think the stud would be tough not hard, as in En8 or 16. Hardening would make the thread brittle and likely to break. Usually studs can be drilled out and removed with normal HSS drills. I have never come across a hard stud since forces are in tension with no abrasive action requiring hardness.
|Thread: Metrication of models|
Bruce. Metricating does not change copyright. I believe a design has to be substantially changed to create a new copyright. Consider people like Dyson etc and their copyright infringement cases.
I am three years into making a 3 1/2 “ Evening Star, slowly. While following the book and plans with regard most dimensions, drills are metric as are reamers, taps and some material thicknesses. When I started I was going to create metric drawings and model in Fusion360 but quickly decided to mark up copies of the drawings as I went along. I’ve only bought the expansion link brackets and cross heads as gunmetal castings but needn’t have bothered as the castings are more trouble than making from scratch due to material thicknesses and out of position elements make machine to drawing near impossible. So far the rolling chassis is nearing completion.
|Thread: Leadscrew material ?|
Also square thread has no compensation for wear.
|Thread: Thread Size Help|
Never owned a Leica, thread from reason new to me. Camera threads
|Thread: How to repair old King Dick socket extension?|
It is probably a pressed in insert with a ball and spring, or was. I would press out the piece/socket you can see, get a ball that just slides into the bore of the socket. Then put a spring into the socket power fulll enough so that when you sit the ball on top you can press the ball into the socket. Now with the ball depressed punch the top with a centre punch to close up the bore to retain the ball and spring and press back in.
You can buy detents from various mechanical engineering sources such as WDS, but may not find you size.
|Thread: Havenít done this for a looooong time!|
Bearing locknut is M12x1, if that helps.
I went from imperial in mechanical engineering at college in my third year to another college for my fourth year which was metric. Somehow I still managed to be one of six out of twenty that passed at then end of year and was offered a place at university, but had to turn it down. Throughout my working life I had no problem working in either units.
|Thread: Why are washers such a poor fit?|
+1 for Martin.
if you intend to use the washer as a seating for a nut then by all means make the hole smaller and possible make the washer thicker. As an alternative locate the washer in a shallow counterbore to retain its position.
|Thread: Work holding?|
Where concentricity is important.
Place slightly longer piece in 3 jaw chuck.
Face end, centre drill, drill and ream.
Place a mandrel in a collet chuck to hold the part to face the unfinished end and skim the outside. My mandrel are usually a bit of bar turned while held in the collet with a screw or nut to clamp the part in place. I realise you have to use material to make a mandrel but mine get reused for different parts, or you could buy a mandrel. In day gone by you could use a standard mandrel which has a slight taper to hold the part and centres in each end to hold between two centres.
i am sure you will get many suggestions, but that is the way I work on my mini lathe.
|Thread: Working leaf springs|
I bought some from Reeves about 12mm wide 1.2mm thick, it is intended for 3 1/2 loco tender springs. The job is on the todo list soon, the hangers are roughly made awaiting the finishing of the slots.
|Thread: Calculating DRO For Mill Z Axis|
What if you connect the scale to the knee and the reader to the quill. Then you read the distance between the two.
|Thread: Hints and tips for cutting small(ish) male threads with a die|
I use size to minus for material and cut with hand turning n the lathe using the tail stock to keep square. Use cutting oil and back off frequently with the die set to maximum open. Turning the material through the die too quickly and not backing off will cause the swarf to strip the thread to a degree. I cut metric down to M2 with no problems in steel and brass.
|Thread: Any 5" Gauge Ground Level Turntable Articles or Advice?|
Use a lazy daisy, ie table centre rotary stand
|Thread: Repair required for Milling Knee|
+1 stitch repair. Forgot about this have seen it used in the past for both full break and crack repair. Google it, a few companies about who specialise in this.
Machine both pieces and add a piece in between, use a tenon and slot to give some sort of positional key, and screw together. Obviously the assembly will need licking up to get is all true again. Alternatively can you machine it and add a new plate and nut bracket, obviously this would move the other slide dovetail further out, but may give you more material to bolt into and taper pin to retain position.
|Thread: Anyone know where I can get hold of 'Gauge Rods'|
How accurate are you hoping to get. It seems that you are comparing rather than measuring, so why not use slips under a microscope or some other optical comparator. I am sure there is someone here who worked in an inspection department that could make a recommendation.
|Thread: 4 jaw Self centering chuck recommendations please|
I use a 125mm four jaw from ARC, it was one of the narrow ones a little lighter than the full chuck. It works great on my SC3 when I need to hold bigger diameters than the standard 80mm three jaw.
|Thread: Stripped the drive belt on my Chinese Mini lathe|
I would stick wth toothed belt rather than polyvee, as I would expect the belt tension to be higher on polyvee. The reason I say this is the life of the motor bearing with higher tension. My motor stops with an error if the cutting torque is too high for it and this has happened quite frequently over the three years or so I have had the machine with no electrical problems ( may be one day I will get a bigger machine!!).
I shredded my belt after three years of use. As I couldn't get a replacement I bought a 5M set of belt and pulleys. Fortunately I had a mill so was able to bore out both pulleys. Still working six months later. I prefer the 5M setup as the teeth are a more positive drive form, a little more noise but not obtrusive. Also the belt is readily available.
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