Here is a list of all the postings colin vercoe has made in our forums. Click on a thread name to jump to the thread.
|Thread: Taper identification|
Hi the measurement given in your chart might refer to the Gauge Line measurement, this is a little further back the taper and not at the end where you are measuring from, the picture you have posted shows a line further back on your taper where it fits your taper this is the Gauge LIne measure here and see what you get.
|Thread: Dressing a diamond wheel|
I ment to mention that diamond wheels are for carbide and Borazon are for HSS, the same rules above apply to both.
To dress a diamond wheel you use a dressing stick which has the appearance of a long half inch square slip stone this usually came with the diamond wheel this was a Norton wheel, switch on the grinder then switch off, then stop the wheel with the dressing stick, repeat until the wheel has been cleaned, this process clears out the ground carbide from the wheel face leaving the diamond exposed ready to use. This process only clears out the carbide and does not reduce the wheel size.
To true the wheel you use a truing tool about 8mm diameter sintered metal containing diamond particals, this is held in a vice or chuck etc and touched onto the wheel then passed across the face of the wheel this then trues the wheel by removing the diamond high spots, after doing this its best to keep wheel mounted on its arbour and remove it by removing the wheel and arbour complete, this requires arbours for each wheel if you can do this.
look at the Norton website if they are still going that is
|Thread: Bolts or studs|
When making studs two thread gauges are used, the end that is fixed is made slightly larger than the nut end so that it fits better into the component and locks, this allows removal of the nut without the stud coming out.
|Thread: Hydraulic ram machining|
Best to groove the rod with grinding disc where the machining is to finish so that the chrome is not lifted from parent metal, also for cross drilling remove the chrome on both sides of rod for the same reason, the company where I worked used pre ground stainless steel bar available in various sizes which is used for hydraulic rams and we made our own.
Hydraulic ram specials are not that expensive at about £150.00 - 200.00 quid each, try a company called Applied Fluid Power from St Austell Cornwall you might be pleasantly surprised.
|Thread: HSS replacement tool tips.|
Try Plansee Tizit lots of info here
The tips you require are available from Plansee SM 80 grade sintered HSS various sizes and geometrys brilliant tips and can be re lapped. use speeds and feeds as for HSS these were available 20 years ago plansee way ahead of most of the tip manufactures at the time
|Thread: Drilling X2 chilled casting|
sharp masonry drill should do it must be sharp, or try reducing the helix angle of hss drill [brass type cutting end] this works as well, beware if drilling a through hole as when close to other side the higher cutting pressure can cause damage as the drill breaks through.
|Thread: Milling Insert Clarification|
TPUN is a turning insert geometry but can be used for milling but not as robust, go for TPUN 160308 the 08 being the radius on the tip cutting edge.
TPKN is a milling insert same triangular shape and thickness but the KN denotes ground facets on the cutting edge instead of the 08 radius more robust and a better finish, also more expensive
|Thread: where to buy a good open morse taper 4->3 sleeve|
I had a new Dormer sleeve for similar purpose and cut the end off with a disc grinder, worked fine
|Thread: Hose thread queery|
|Thread: Leadscrew suppliers|
Halifax Rack and Screw company, if they are still in operation.
|Thread: Elliott M10 Tapered Ram and slideways|
Dont despair, many older machines before induction hardened beds etc picked up on the slideways especially shapers and planers with fast slideway operating speeds, to overcome the damage caused the the offending areas were ground away below the mating surfaces, all loose particals and dirt removed and put back into service.
The area can be hand scrapped or removed with a die grinder / dremmel or even a chisel, once completed the pitted area becomes another oil reservoir and will give years more service without any trouble, it really isnt as bad as it seems give it a try you will be pleasantly surprised with the results and you will get a useable shaper as well!
|Thread: Hard Surface on Black Mild Steel?|
Hard spots in steel can be caused by old carbide tips thrown into the swarf tray of machines the the scrap is reused into new steel the offending tip does not melt and mix with the new steel and you hit it when machining the new billet.
|Thread: Drilling very long holes|
You could use a Gun drill bit, not really a depth limit with these bits, at the firm I used to work we drilled 10mm dia 700mm deep in stainless steel plate with cutting oil fed down through the bit this was in one cut without retracting the bit as the chips are ejected along the flute of the drill bit by the coolant . You can also use compressed air with misted coolant as a cutting medium again the compressed air ejects the chips along the flute of the drill bit and also cools and lubricates the cutting area, again very good results try Sterling Gun Drills, or Mollart Gun Drills, if they are still going
|Thread: Parting off|
The tipped parting tools cut much better and are more reliable they are usually made from one piece of material and tend to be more rigid and dont tend to jam as much, the tip geometry is designed to curl the chip and make it leave the groove easier, HSS parting tools are normally in a holder sticking out a long way from and overhanging from the tool post reducing rigidity with minimal side clearance they tend to jam all the time
|Thread: Tufnol - cylinder block?|
Worth remembering that prior to year 2000ish Tufnol might have contained Asbestos so be careful of the dust.
|Thread: Centre finding|
spotting drills also pre chamfer the hole ready for tapping etc, they work very well in a milling machine as chamfer milling cutter.
|Thread: Burnerd Multisize collets vs Crawford Multibore collets|
With the Crawford type there are lots of size and shapes of these out there in industry so always a good supply to chose from, dont know much about the Burnerd though
used to use crawford collets collets on a Emimec Sprint auto lathe, would run all day 7 days a week never a problem
you can get some with grippers in the bore to stop bar push back, but they all rust if you let them.
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