Search found 191 matches

by choprboy
Fri Jun 22, 2018 9:13 pm
Forum: General Discussion
Topic: not how they teach you to do it in school
Replies: 10
Views: 529

Re: not how they teach you to do it in school

Better than a spiral point (gun tap), is a spiral flute tap. I do 12mm power taps in the drill chuck of my mill all the time. Takes a bit of experience, but get everything lined up and make sure you have enough quill length for the hole, turn on the motor and let the tap gently drop into the workpie...
by choprboy
Thu May 24, 2018 11:11 pm
Forum: General Discussion
Topic: 4130 chromoly
Replies: 5
Views: 656

Re: 4130 chromoly

I have turned a bunch of 4140, 1-4" pins/collars/threaded rods, no idea what temper, whatever IMS sells. A bit of brushed on cutting oil, HSS drills and threading/boring tooling, or high speed and carbide inserts. Chips come of hot and can take a bit of fiddling with speeds and feeds to make a clean...
by choprboy
Tue May 22, 2018 2:25 pm
Forum: General Discussion
Topic: OT Using DryGas in alcohol blended gasolene
Replies: 9
Views: 635

Re: OT Using DryGas in alcohol blended gasolene

The alcohol from the gas pump is ethanol. Dry gas is methanol or isopropyl alcohol. All of those are hygroscopic and readily absorb water into the mix (though some people say ethanol more readily breaks down and releases that water?). Personally... I would side-step and say leaving ethanol-gas in th...
by choprboy
Tue May 22, 2018 2:03 pm
Forum: Lathes
Topic: C0630
Replies: 4
Views: 537

Re: C0630

I don't understand your question... lathes have threading dials to ensure you re-engage the threading lock on the same position of the lead screw relative to the rotation of the spindle, which varies based on the lead screw/gearing of a particular lathe setup. When cutting a thread that is a fractio...
by choprboy
Tue May 22, 2018 1:31 am
Forum: Lathes
Topic: C0630
Replies: 4
Views: 537

Re: C0630

No direct information, but have a look at this previous thread and use a web translator on some of the linked Chinese pages: http://www.chaski.org/homemachinist/viewtopic.php?t=102256 In particular I notice that one of the pictures shows what appears to possibly be a small 30-ish tooth gear on the s...
by choprboy
Sun May 20, 2018 2:57 am
Forum: Casting & Foundry Work
Topic: Things they dont tell ya when you start casting. :)
Replies: 20
Views: 1177

Re: Things they dont tell ya when you start casting. :)

2) Is a steel crucible a good option for aluminum? No... Lots of people use it, but unless you need to do something special/oversize/etc., I wouldn't use one repeatedly. Iron actively dissolves in aluminum, meaning you contaminate the charge and erode away the crucible. Additionally, the steel exte...
by choprboy
Thu Apr 19, 2018 11:44 pm
Forum: Buy, Sell, Trade, Wanted, Free!
Topic: WTB: 5C collets and blocks or divider ndexing plates
Replies: 3
Views: 480

Re: WTB: 5C collets and blocks or divider ndexing plates

Yeah, the first couple things are relatively straight forward. I already have a 5C spin indexer, but only a handful of random collets. Several of the things I need to do are a fair bit large though... 24 splines in a ~2" bore of a ~5" flange and 6 notches for a ~3" castellated nut. Easy to divide in...
by choprboy
Thu Apr 19, 2018 2:33 pm
Forum: Buy, Sell, Trade, Wanted, Free!
Topic: WTB: 5C collets and blocks or divider ndexing plates
Replies: 3
Views: 480

WTB: 5C collets and blocks or divider ndexing plates

Looking for a standard set of 5C collets and hex block (dodecagon would be great), no preference on brand. Or some indexing plates I could use to make a custom index fixture. I want to cut some splined shafts and collars, but not exactly sure how I'm going to do it yet. Probably single-point broach ...
by choprboy
Thu Apr 12, 2018 2:48 pm
Forum: Favorite Places to Shop In Your Area
Topic: HGR industrial surplus. Euclid Ohio
Replies: 18
Views: 8353

Re: HGR industrial surplus. Euclid Ohio

I recently tried to buy from HGR after oggling for a few weeks... but I had to cancel the order. They wanted $250 to ship a 100lb chuck across the country. Is this normal? I get a standard crap UPS shipping rates and it only cost about $150 to ship 140lbs in the other direction. You just have to be ...
by choprboy
Wed Apr 11, 2018 11:59 pm
Forum: General Discussion
Topic: Threading inserts
Replies: 2
Views: 523

Re: Threading inserts

I suppose the laydown type are "state-of-the-art" as they profile both the bottom and top of the thread simultaneously. But, unfortunately, that also means they are many part numbers, each specific to certain thread pitches. A single V type (HSS, triangular, triangle-on-its-side) can do a larger ran...
by choprboy
Thu Apr 05, 2018 12:13 am
Forum: Milling Machines
Topic: Need help with a rockwell 21-100
Replies: 4
Views: 728

Re: Need help with a rockwell 21-100

Easy. Disconnect the motor wires from the power switch if necessary (varies between units, most have been pre or post wired to various reversible drum switches mounted to the column). Loosen the over-arm clamp bolts. Slide the head and over-arm out of the column. Be sure to get the shaft key/secure ...
by choprboy
Tue Apr 03, 2018 3:40 pm
Forum: General Discussion
Topic: How do I use a shaper?
Replies: 14
Views: 1412

Re: How do I use a shaper?

I would think no... and not for the most immediately thought reason. First, with a 7" shaper you would have to take at least 3 passes across a 16" surface (assuming you can not machine it in a shorter dimension). That's not too bad as you can adjust both the length and position of the stroke, along ...