Search found 60 matches

by David Malicky
Wed Mar 28, 2012 4:01 am
Forum: Tools and Jigs
Topic: Replace a 3 phase motor with single phase; equivalent power?
Replies: 43
Views: 34986

Re: Replace a 3 phase motor with single phase; equivalent power?

Congrats -- that's a very nice lathe! Hardened ways, camlock chuck, big spindle bore... I wouldn't pass that one up, either! Yes, Halgier is correct on the power factor correction for 3-phase. The rated power is probably around 1.7 HP, which is very reasonable for 11" swing, but you could probably g...
by David Malicky
Wed Mar 28, 2012 1:08 am
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Routing the edges of the top/back
Replies: 11
Views: 6346

Re: Routing the edges of the top/back

Great advice above. If you want some insurance, a down-cut spiral bit keeps the fibers planted as they are cut. I use a Whiteside RFTD2100, which seems immune to chipout, going in any direction. Or a down-shear bit (e.g., Whiteside 2602) has some of the same effect, at lower cost as it's not solid c...
by David Malicky
Thu Mar 22, 2012 7:24 pm
Forum: Tools and Jigs
Topic: Tools and Rust
Replies: 22
Views: 14318

Re: Tools and Rust

A few options I've tried - Boeshield T-9 is a spray-on wax/lube (developed by Boeing, thus the name). It leaves a paraffin film. It works well, though seems to wear off surfaces faster than I was hoping. - Turtle wax lasts quite a long time, although once I learned it has silicone, I stopped using i...
by David Malicky
Sun Mar 18, 2012 2:23 pm
Forum: Wood and Materials Q&A
Topic: wood for solid linings (non-kerfed)
Replies: 15
Views: 15998

Re: wood for solid linings (non-kerfed)

Heavy (and stiff) linings give more impedance for top to push against, helping reflect vibrations and increasing the 'main top' active area. Trevor Gore's book has details. I use oak -- 1/8" bends easily.
by David Malicky
Thu Mar 15, 2012 2:13 pm
Forum: Tools and Jigs
Topic: SawStop Table Saw for Lutherie
Replies: 12
Views: 8743

Re: SawStop Table Saw for Lutherie

No way to use 7 1/4" blades, but 8" blades would work with the dado cartridge. Freud LU83R and LU88R 8" blades are .083" kerf. Diablo 8" blades are .087"-.094".
Thurston Mfg will custom grind a blade for fret slotting.
by David Malicky
Sat Mar 10, 2012 4:02 pm
Forum: Tools and Jigs
Topic: bending machines vs bending iron?
Replies: 23
Views: 18808

Re: bending machines vs bending iron?

A few factories use an iron, handled by some very skilled people:
Martin for some guitars, 4:30 in -- http://www.youtube.com/watch?v=SFNYxjlU_-0
Eastman, 0:38 in -- http://www.youtube.com/watch?v=mtBlGRmnmJE
by David Malicky
Wed Mar 07, 2012 10:10 pm
Forum: Tools and Jigs
Topic: Dragon rasp?
Replies: 19
Views: 12625

Re: Dragon rasp?

I have the 4151 Large "Coarse" - it's awesome! But I would call it a medium rasp, in comparison to most "coarse" rasps.
by David Malicky
Mon Mar 05, 2012 8:50 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Semi-Hemispherical fret work
Replies: 35
Views: 14745

Re: Semi-Hemispherical fret work

Here's our process for student-project guitars, starting around 3:20 in: http://www.youtube.com/watch?v=PpZSwsHQ9eU The sanding jig shown is great if you have many necks to make. For just a few necks: cut them long, square and dress one end of each fret, lay in the slot with the dressed end ~1/32" i...
by David Malicky
Sun Mar 04, 2012 3:55 pm
Forum: Tools and Jigs
Topic: bending machines vs bending iron?
Replies: 23
Views: 18808

Re: bending machines vs bending iron?

Some builders do bend 2 sides at a time (e.g., Trevor Gore). My current bender does 1-per but I'll go to 2 for my next one. More than 2 has some issues: the heating watts are more than a wall outlet can put out, and if you have 1 troublesome side, the other 3 would have to go along. Here's a semi-au...
by David Malicky
Fri Feb 24, 2012 4:20 pm
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

On the resistance tests, the motor would need to be hot and showing the problem for a multimeter to have a chance of finding an insulation fault. Even then, as mentioned, only a megger meter (applies 250 volts to simulate in-use insulation breakdown) can definitively test for faults. Motors running ...
by David Malicky
Wed Feb 22, 2012 9:20 pm
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

Good work figuring out the multimeter. Unfortunately if the meter has a max ohm range of x1k, it probably won't be able to detect insulation faults (insulation should be in the Mega-ohms... bad insulation might be 0.2 Mohm, 200,000 ohms). Most digital meters will do Mohms, though multimeters don't a...
by David Malicky
Wed Feb 22, 2012 3:49 pm
Forum: Wood and Materials Q&A
Topic: Wide vs tight grain
Replies: 4
Views: 4133

Re: Wide vs tight grain

Yes, for an individual piece of wood, the way to tell is to test it. For trends, the best study I know of says uniformly tight grain wood does tend to have higher longitudinal modulus and velocity of sound, but also tends to be heavier, like Rodger said. See Figs 7.3 and 7.4 here: http://books.googl...
by David Malicky
Wed Feb 22, 2012 3:23 am
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

Hi Gerry, Good info. It does sound like the rpms were pretty low, and thus likely the switch was engaging then and not the cause of the problem. Yes, the contacts are in series and that makes it even less likely the switch is the problem -- if either became stuck closed, the other would break the ci...
by David Malicky
Tue Feb 21, 2012 3:40 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Spectral Analysis of Guitars (Acoustic Adicts)
Replies: 2
Views: 2418

Re: Spectral Analysis of Guitars (Acoustic Adicts)

Thanks. Yes, the 'science' discussions were painful, but the video was still interesting, and some good recording comparisons.
by David Malicky
Tue Feb 21, 2012 3:05 pm
Forum: Tools and Jigs
Topic: Makita 12" Planer vs. a small Drum Sander
Replies: 19
Views: 17911

Re: Makita 12" Planer vs. a small Drum Sander

Brad, Interesting info -- I'm shopping for a planer, and wondered what was preferred about the Makita planer over the large spiral planer?
by David Malicky
Tue Feb 21, 2012 4:15 am
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

Hi Gerry, Good work taking it apart and inspecting things! And the pics are very helpful. Now it's a process of elimination. So, if the spurts are indeed the start winding kicking in, as DT suggested, then the switch would be working normally. When you say you thought the motor was off entirely befo...
by David Malicky
Mon Feb 20, 2012 3:29 pm
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

DT has an interesting point on the spurt of energy. That would depend on what rpm the spurt occurs at. On slowdown, the mechanism switches over at a pretty low rpm. Do the spurts occur at a similar rpm that you hear the 'click', or higher? Bad bearings seem unlikely to me for a few reasons... motor ...
by David Malicky
Sun Feb 19, 2012 6:26 pm
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

Hi Gerry, glad to help. Good tips from Celeste and Clay. If the switch's contacts are closing normally when the motor is at rest, don't be surprised if you see no spark when shorting the capacitor. With the contacts closed, the capacitor should discharge itself through the windings (see schematic ab...
by David Malicky
Sat Feb 18, 2012 4:44 pm
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

Good googling, Gerry. The key info is "capacitor start, induction run" -- that's the type of motor (often just called "capacitor start"), and a good choice for a thickness sander. It has 1 capacitor and a centrifugal switch. Here's how it works... - Schematic: http://lh4.ggpht.com/_X6JnoL0U4BY/S1cH_...
by David Malicky
Sat Feb 18, 2012 4:17 am
Forum: Tools and Jigs
Topic: Why Is Thickness Sander Motor Stalling
Replies: 48
Views: 30045

Re: Why Is Thickness Sander Motor Stalling

It may help to figure out what type of motor it is. A few questions for that... - Does it have a centrifugal switch? (Makes a 'click' sound when the motor spins down after turning off. Also visible when taking off the end-cap.) - Does it have 0, 1, or 2 capacitors? (Usually on the side of the motor ...