1 x 8 tap

Re: 1 x 8 tap

Greg W. in NC

>DW,

I think I used a 7/8" forstner on several pieces of hard maple. I used a vice grip or crescent to drive the tap. Of course you can always practice on a scrap piece, if you don't feel that comfortable at first.

Re: 1 x 8 tap

Steve Roxberg

>The tap I bought told me on the box what size hole to drill. Check your box.

Re: 1 x 8 tap

John Lucas

>Most taps I have the drill size is written on the tap.

Re: 1 x 8 tap *LINK*

Fred in NC

>There are charts all over. The charts are for metal, of course. For wood the hole can be a little smaller.


Tap and drill chart

Use 1/8" smaller drill for all 8tpi sizes.

Al Crandall

>Eight threads per inch need about 1/16 depth per side regardless of the size shank they are used on. 1-8, 1 1/4-8, and 1 1/2-8 threads would all use a tap drill 1/8" smaller than the thread size.

While I'm at it, a small peeve of mine is the use of "x" in designating thread sizes. "x" is pronounced "by" and is usually a distance measurement as in "a 2x10" or a "2x4" when referring to lumber sizes. If you ask me for a 1/4x20 bolt, I'm going to try to find you a bolt which is 1/4 diameter and 20" long.

Therads are described with "-" to designate the number of threads per inch. The "-" is not pronounced when spoken. Your tap in question is an 1-8 tap, and is pronounced as "inch eight" tap. If it were a fine thread tap it would be an "inch twelve" tap. I had a clerk in a hardware store try to sell me a package of "ten thirty seconds by 1" screws. I explained to her that ten thirty seconds is the equivalent of five sixteenths and is much larger than I wanted. I needed ten thirty two by one screws, or 10-32 x 1. The tap for the screws is just a ten thirty two tap.

Al

I have no threads with a by in them.

Re: Use 1/8" smaller drill for all 8tpi sizes.

DWFII

>It's always good to get such things off your chest. [smile]

I apologize...and confess to ignorance and an unreasonably blind tendency to follow convention when I don't know any better. Since my Jet owner's manual specifically describes the spindle as 1 x 8 and since I've been looking at woodworking catalogs for over a year now that use the same terminology, I just thought it was proper (and wise) to go with the "flow," so to speak.

At any rate, thanks to all for your help. My tap doesn't have anything stamped on it (remember, it's a Grizzly) and the box it came in was a generic box probably not intended for taps. After mic'ing the tapered end of the tap and checking the diameter of the shaft at the bottom of "teeth," I thoght 3/4" might even be loose. But from what I've read, I'm gonna go with the 7/8" forstner.

Thanks again.

Re: 1 x 8 tap

Don Henthorn Smithville, Texas

>DWF, i use a 7/8" spade bit and had no problems.

As for holding the tap here is a picture of a walnut holder I copied from one shown by Bob Smalser. He recommended making it longer but I already had it made by the time he said that. I would follow his recommendation. Another way to hold the tap is with a mechanic's speed wrench a reducer and a 5/8" or 11/16" socket. I can't remember what size fit the end of the tap.

Sorry for the pic but I just ran out to the shop and snapped a pic for this post.

Re: 1 x 8 tap

DWFII

>Thanks Don. I was hoping you'd chime in here since it was your post that got me started down this path. Thanks for taking the time to shoot the photo and thanks for taking the time to make the intial set of posts, in the first place. BTW, I think you said you paid roughly $10.00 for the tap from Grizzly. When I went to order it was $29.00+ and $34 something with shipping. No problem...just for those looking to buy one from Grizzly. I bet it's a great price even at $34.00

Again, thanks

Re: 1 x 8 tap

Lan Brady

>Thanks for the picture of a handle. I have been using vice grips that make me off balance starting the tap. I too use a 7/8" hole. I do put CA glue in the treads of the wood after it is tapped. May not be necessary, but I take no chances. I have not had a single face plate to fail.

Also, I bought my tap on e-bay for $6 + 6 for shipping. Still a good buy, it has tapped more than 40 holes.

Lan

Re: 1 x 8 tap

Don Henthorn Smithville, Texas

>You are welcome. I think I posted that the taps were on clearence when I bought. Don't know how many they had but I think my post on this and another forum may have helped them sell out. No connection with Grizzly.

Re: 1 x 8 tap *LINK*

Karl

>Here is another great source for lots of metalworking products: http://www.jlindustrial.com/catalog/product.jsp?origin=SEARCH%3ACATEGORY&id=TAP-14143E#

This listing is for a standard 4 flute 1-8 tap for $20.33.


http://www.jlindustrial.com/catalog/product.jsp?or