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: 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.
|Thread: Gear Measuring|
These may be able to help, KHK
What measure the gear?. You have two that you could use to make a single point cutter from. Then turn a blank to the same diameter out of say, 817M40 (EN24). Setup using one of the gears to set depth of cut. Cut gear blank, probably cut a sample from ally if you like. The flame harden the teeth, or take to a hardening shop with induction coils.
I’ve always called it scraping, whatever it’s end purpose was, after all you wouldn’t want to make the surface worse than it was prior to further working. Even f you are breaking the surface to create an oil receptive one you would still need to check the dimensional/geometrical accuracy of the finished mating parts.
|Thread: Tapping Holes Material Thickness|
Not sure what you are asking, is it the distance from the hole to an edge, or the distance from the bottom of the hole to the other side of the metal. For AF of pipe fittings have a look at standard parts, at your pressure air fittings are more than adequate. For the alternative question, assuming pressure from the inside on solid metal towards the hole, it will depend on hole size and I am sure some one here can give a guide or the correct formula.
There are plenty of articles and videos available to give the information and the how. But for simplicity, when two ground faces interact they create a stick and slip situation, and the surfaces can be completely devoid of lubricant. Scraping one surface leaves small pockets in which oil can reside. Bluing and scraping the surfaces allows you to match the two surfaces, removing high points. Typically the longest length, the bedway, is ground along with the matching part surface, but the this being shorter is blued and scraped. Scraping can also be used to correct small geometric errors on other non contact surfaces.
Some people take classes to learn the art of scraping and it is not a quick process unless you just want to remove the worst of the error.
|Thread: Solid carbide end mills|
I decided to make my own loco wheels from solid rather than using cast so have milled eighteen spoked wheels. Used 3 mm carbide initially for finishing but found the speed on the SX2P limiting and bought HSS in packs of ten from Amazon, worked well enough to convince me that HSS was my better option. I did break a number but at the price I wasn’t bothered and most broke due to the rough cut out causing too big a cut and poor swarf clearing in the setup.
|Thread: Problem with slitting saw arrangement...|
Always use a slitting saw under 3mm (1/8" without a key, faction between on the blade between the spacers should be enough to hold, if not too much force is being applied to the cutter. In my apprentice days on horizontal mill always removed the arbor key, it was quicker than making a new one after fessing up to the foreman.
|Thread: Horizontal Bandsaw - Final Thoughts|
I have a Clarke 6X4 1/2, bought a couple of years ago. This goes along nicely with a mini mill and mini lathe. In that time I replaced the supplied blade with M42 blades in 14/12 and 6tpi for a much better cut. I accept the down sides of a saw like this and have replaced the motor after jamming a blade when I wasn't present. But am still quite happy with what it can do with a little care. The alternative is to get a proper industrial saw, heavily built, overpowered and ability oi be accurately set up at a much higher cost and floor area. the question I ask is how much is it going to be used, mine can sit for a week while I mill/turn the pieces I have cut in ten minutes. If you are a fabricator then you will cut more unless it is sheet steel and unless you have a bigger lathe how much bigger do you need. Even if you had a ten inch swing lathe and full size mill the material size to cut will depend on what you are making.
So I am happy with an import which will do what I want while I stand and watch it for a few minutes a week.
|Thread: Strange clamps|
Looks like a production shaft cross drilling jig. The bushes are Grip drill bushes for guiding the drills. Used to use Grip in the 70's, they used to make the whole range of fixture components in those days in competition with WDS. Not sure when Grip expired, bushes now made by B&T in Nottingham and others.
|Thread: Midlands Garden Rail Show|
Show is on in March. Link here **LINK**
|Thread: Is CAD for Me?|
I went from manual draughting in the 60’s to 2D CAD in the 80’s and finally 3D CAD in the 90’s. I found the best way to produce a 3D model was to start with a block and take shapes away, as you would machine a piece. In the real world I found that modelling from nothing, adding shapes together often created difficult or impossible machining.
|Thread: Which Qctp for mini lathe?|
I have used a 000 on my SC3 since I got it three years ago, made further tool holders in various styles to suit tools and dti. All good and still clamps ok.
|Thread: help with gear calculations|
Phil could probably shim the rack to mesh properly with the gear, to take out any error on gear size so long as Dp is correct. The rack tooth form looks like a straight full Dp tooth form, not one with differing addendum and dedendum. Easy way to make would be to heat shrink gear onto shaft as gear is going to be the most trouble for a beginner with limited kit.
|Thread: Pivoting bolt|
See if something here will do.
|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!
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