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: Taper pins|
Taper pin drills, drills with a taper, are available for those who wish to drill a tapered hole before taper reaming.
|Thread: help with gear calculations|
Just reach for gear suppliers. The main are people like HPC, KHK, Davall and others most are quite happy with small one off orders as even industrial users often only need one.
I suspect it might be 12DP gear. Although working on 1 9/32" and 17 (T+2) it comes out at 13.333DP. Can you measure the rack teeth length over say 10 or so teeth, this will give you the pitch length, then the DP can be calculated from that.
Have a look here for tooth dimensions, if it is a help.
|Thread: How does this collet work?|
A link to Google books for those who need to read further.
With those sort of dimensions a four post lift would be possible with ball screws in each corner connected by chain or possibly toothed belt. For simplicity you could hand turn them. The problem is the supporting frame for each panel to prevent them bending. I think you need to sketch it out to see what you actual loading is on the floor, you may be adding more weight than you think. Could you slide the panels under the rest of the track and slide and lift one into place at a time, possibly with a simple cam action lever, this would lessen the weight being moved.
You have weight?? A car jack uses a screw about 16 mm dia to lift a quarter of a car!
As Mike says, dangerous in this situation. I would use a simple trapezoidal or acme thread, perfect for occasional movements. Ballscrews are used for applications where in continual movement. While the load is perfectly acceptable you would need some sort of safety device to arrest. There are many types of ball nut for different mounting ways and accuracy, a simple reversed flange nut would do what you want. Also need to consider the dirt that is around, fine particles would soon wear the ballscrew even with wipers. Best to look up a UK manufacturer and give them a ring for advice. I used ballscrews in machine tool designs for years, and although some were rebuilt at service rebuild time most outlasted the component the machine was producing.
|Thread: Taper pins|
Taper pin holes are reamed through so that the small end, nominated diameter of the pin, goes through an extends slightly beyond. Then the excess length is removed to give a clean finish. I would think these days taper pins are used for shear pins mostly as Seloc type or roll pins are an easier fit.
|Thread: Restoring a Myford ML1|
Give it up now. If you had access to a reasonable size mill and lathe for free, access to metal for free, and know someone with machine tool experience then I would say have a go. But as a complete beginner, don’t bother unless you have deep pockets and endless time. Minor faults on a running machine can be sorted as and when required but a complete rebuild is another matter. I have worked with machine rebuilders in my past life, the money and time thrown at a working machine is ridiculous about 50 to 75% of a new machine when and if they were available, but the customer ended up with machine of greater accuracy and longer potential life with the upgrades. But here I am talking of production machine probably no more the five to ten years old. A clapped out wreck is useful to put in the corner as a project for the future, that way you can spend your hard earned cash on something that you will no doubt upgrade in three years time, the balance weight will still be there for your retirement project. Plenty of useable machines out there both new and second hand and plenty of people can tell you why there’s is the best to buy. Just by something that you can learn on and look to the present and the future will come.
|Thread: Beginners question (sorry) - why I am breaking my small centre drills?|
Check that the tailstock spindle doesn’t move around, any free play will try to bend the centre drill off centre. Slightly clamp the spindle to stiffen things up. Use a collet chuck rather than a drill chuck to try to get better true position.
|Thread: Childhood diseases|
Like others I was sent to the latest infected child in the 50's. Had about everything going by the time I was 10, except for chickenpox, caught that of my kids while on holiday in Florida in the 80's. They had it the week before while I was in Sweden on buisness.
|Thread: How does this collet work?|
It is a Morse taper split sleeve drill driver. The drill to suit the driver is parallel shank with a small pair of flats on the end. Used in production setups for small drills, cheaper to use with replaceable straight shank drill rather than morse taper. Used to use these quite a lot on multi spindle drill heads with smaller, sub 10mm drills.
|Thread: Fake Websites|
Was going to suggest to check that a padlock appears against the web address, making it a secure web site, but having checked a number of links I have most are not secure. Perhaps people with older web sites should check that they have the current required security levels to protect both their site and its visitors.
|Thread: Parting off query|
If you snapped the blade then it may be plain HSS. I had this happen to mine and changed it to a M42 HSS-Co8, had a few snags but the blade has remained as one.
|Thread: Drilling cast iron - where did I go wrong?|
As Mark said, drill from solid or a spotted hole. Using too large a pre drill will cause chatter as the drill or bends as it rotates grabbing at various points during rotation. The alternative is to use a core drill in a predrilled hole. Core drills are three or four flute drills which are meant to be used for opening holes out, they have no point only chamfer on the leading edge so stay centred on a pre drilled hole. Also they are run slower at greater feed.
|Thread: Backlash on SX2p mill|
As Jason said adjust the leedscrew nuts. If you wind the axis out to its maximum the adjusting screws can be seen. Adjustment stretches the split nut to apply some tightening on pitch. You have to do it at the end of travel then see what happens at the mid position, which is were most slack probably is. Mine is only three years old and reasonably worked but still adjusts ok.
|Thread: Z Axis-Support|
It looks as you have the cylinder mounted with the rod up. Manufacturers recommend rod down so that the rod seal remains lubrcated.
|Thread: Keyway steel|
According to Macreadys orange book, EN6A - 080M30, is key steel. It is as supplied finished to British Standard, both imperial and metric key tolerances. Key steel can be bought in 12 inch lengths as a minimum, I think we always bought 36 inch, from most bearing suppliers. But do as most people do and use what is to hand.
|Thread: Chinese dovetail cutter|
I bought a HSS dovetail cutter from Tracy Tools at a show about 12 months ago, £15, has performed well in steel. Probably cut about 1000mm so far with occasional use of aerosol lubricant. Make sure the cutter diameter is big enough for the depth you need to cut, and small enough to get between the inner corners of the ways.
|Thread: Dishwasher detergents|
+1 for everything Aldi. Have been a regular shopper there for 20+ years. Detergents are all very good.
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