Here is a list of all the postings bernard towers has made in our forums. Click on a thread name to jump to the thread.
|Thread: Small drill bits, <<1mm|
The only problem with a .3 centre drill is that the .3 tip is very short and fragile why have the problem when there is a solution that’s cheap to make and almost impossible to break,
Unfortunately the spade tip of even a small center drill is larger than the intended drill which can allow the drill to wander. If you have a piece of 1/8 carbide or hss grind 3 or 4 facets giving a approx angle of 60deg and a sharp point, make a small divot which will be the lead in for the drill. The idea came from a cnc website and they were charging over £40 for just one of these!!
|Thread: internal grooves for o rings|
Not sure what use you are putting your o rings to but I personally have not ever seen an o ring groove with a rounded profile, all the ones I have seen are square bottomed to allow it to deform when fitted and usually they are wider than the ring dia. Not sure if this will help but food for thought
|Thread: DRO error|
I fell into the trap in the early days of my dro but have now got into the habit of adding an extra hole and using an end angle of 360 as Jason suggests which suits most of the work and only requires a little extra thought if starting at a different angle.
|Thread: ER collet adapter|
Just goes to show you get what you pay for even in fasteners. I machine a lot of stainless socket heads for HD’s as in the supplied state the heads can be up to 20 thou eccentric!! It would never have occurred if they had supplied Unbrako’s.
|Thread: Set up tool???|
Thanks a lot it’s obvious once explained, just couldn’t figure out how to use the pointed rod which was enclosed in the center. Amazing the information out there!
|Thread: Turning oil filled bushes!|
I use oilite blanks and machine them with hss tools that are honed sharp without trouble and ream them successfully. I machine them dry and when finished fill them with lube and pressurise with your fingers on either end and you’re ready to go.
|Thread: Set up tool???|
Edited By bernard towers on 19/05/2020 17:04:13
If the parts to be primed are steel why are you using etch primer. Etch primer has been specifically designed for hard to bond materials and steel is not one of them. Much better to use a zinc chromate.
|Thread: What are these for|
Valve guides for ford v8 side valve circa 1940s, they bring back memories!
|Thread: Double ended milling cutters|
I have used double-ended cutters for a few years now in er 11/16/25 collets with no problems. I would think that clarkson type collet chucks would not be of any use as they do not have a through hole which is necessary to get the cutter far enough through the collet to reach the plain shank.
|Thread: 7/8" x 5 tpi acme threaded rod|
Try **LINK** . I have used them in the recent past and were very helpful
|Thread: edm machines|
Thanks for all the info I will get the book from Camden and see what that looks like but after looking at the pics it looks a little bit daunting to a mechanical man with only simple electronic knowledge. Again thanks for all the info.
would like to build a EDM machine but finding information hard to come by. any assistance would be appreciated .
|Thread: Hex Blind Hole in Polyester Resin|
Is it necessary for the hex to be full depth or could the lower half or so be a hole of a diameter that is large enough to clear the points of the hex. I have cut 1/4 hex in aluminium to a depth 5/8 inch, with a home made rotary broaching chuck. I can't imagine that you material is particularly hard so you could concave the front of the broach to give a more aggressive cut. Best of luck
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.