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: 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.
|Thread: Tool post project|
The four pins won’t all press onto the tool unless the rod deforms substantially. Also I think a key and key way would locate the holder, the key can be a flatted pin.
Rather than use two pins why not make the top with two angled faces one acting on the holder and the other on the main body. This will pull the tool holder into the body.
|Thread: Non ABS pipe glue recommendation please|
Could be CPVC, good for 90 C. See here **LINK**
Industrial bed wipers are rubber as their function is to wipe off coolant and swarf as the saddle travels, lubrication is fed through the saddle, so two separate systems. Felt can be oil filled but can also retain small swarf particles, leather can be soaked in oil to a degree and is probably less prone to swarf retention. Either will do the job, but I think neither is ideal.
|Thread: Size of groove for O rings|
There is not a straight forward answer. I have worked with o rings over the years in all types of design, for both static and moving designs. On some problem designs I have worked with the manufacturer who comes up with groove dimensions for the specific operation. While the easiest solution is to work to the standard groove dimension these can be modified, particularly stretching an o ring to fit in a size larger piston groove. The main dimension to work with is the extrusion gap between id and od of bore and piston according to the exerted pressure. The manufacturer catalogues contain all the basic information so start from there, o rings are most forgiving of errors except for surface finish if longevity is a requirement.
|Thread: Most difficult part first|
I try to make parts in order that they can be fitted together. That way I can size parts for fit and they don’t get lost over time after assembly. But it all depends on what you are making, something like a clock requires most pieces to be assembled in one go.
|Thread: Tolerance for needle bearings?|
Check on a needle bearing manufacturers sight. Make sure you know exactly the description of the bearing. Limits and fits vary slightly according to the type of bearing and the housing material. With thinner wall bearings the fit has greater influence on the fit.
|Thread: Armchair Engineering?|
I replaced the material on mine which I bought in 1991 for sitting in front of the computer for six years doing an OU degree. I think the original material lasted about ten years and replaced it with some upholstery fabric which still shows no sign of wear.
The base and back plastic covers are actually clipped in place, a b it of brute force and ignorance is required to separate them. I think that they are like most things and not meant to be recycled. I did break some of the clips in taking it apart but it has held together and is used daily for some hours.
Not much help but unless someone has took some photos of one that is all I can offer.
|Thread: CARBIDE BURRS|
I am using these. Dremel Uk
|Thread: Making from castings or scratch build.|
Currently building 3 1/2” Evening Star from scratch. Retired so time to me is free and if I don’t complete it then perhaps some one else can. Casting prices increased by nearly 60% in less than a year for the main wheels and had already made the cylinders from scratch. But if time is important then castings or just save and buy a finish machined kit. You pays your money and takes you choice.
|Thread: Phillips vs Pozidrive and portable drills|
I also still have a Yankee in my tool bag the bits are still good after 45 years of use. But the thing I found with drill driver bits was to test them for fit in the screw being used, some just don’t fit very well.
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