Second effort with the BP bits

[sethile]

Hello folks,

Finished the second pipe with the Brad's bits. Man, I'm sold on this method, and these bits are fantastic! Thanks, Brad!

I had a couple of issues on this pipe that will keep it in my own rotation. All is not lost however--I've been wanting something like this, and I learned a great deal. I'm starting to get the feel for this method, and really loving it! Here are some shots:






My main problem this time was after drilling the mortise I missed aligned the drill when I started the air hole. It's way too high in the mortise. I'm having a heck of a time lining that up. I can't really see, and had thought I could do it by feel while aligning the block between the tail stock and drill. WRONG! What I thought was the center of the mortise (marked with the point from the brad point drill used to drill it) was actually the top corner of it! Any tips on how to align the drill for the air hole in the center of the mortise while also keeping it against the center in the tail stock?

I also managed to sand into the delrin on the half saddle . I'm going back to hand cutting tenons, at least for saddle bits. The delrin is just too limiting on this type of stem.

I'm not happy with the way I'm drawing the lines on the shaped stummel in preparation for drilling. I'd be very interested in any methods you all are using for keeping the lines straight and the angles correct. I've been using a combination of doing it by hand, and using something flexible like stiff card stock to act as a straight edge that will conform to the shape while still acting as a guide to produce a more or less straight line. How are you folks doing that?

This time I drilled the chamber in three steps using a 5/16" brad point drill first and stopping an 1/8" or so short of the bottom. Then I used the 11/16" bit from Brad (his original shape), then followed that up with the 3/4" bit that I've modified the shape of slightly. Perfect! Felt much better this time.

OK folks, lots of you have these bits now. Let's see what your making with them!

[LexKY_Pipe]

Scott, that is some awesome grain and a beautiful pipe. How are you squaring the shank using this procedure?

[sethile]

Scott, that is some awesome grain and a beautiful pipe. How are you squaring the shank using this procedure?

Thanks, Craig!

Disclaimer: I suspect this is dangerous, and I do not recommend it! If you try it, be forewarned and VERY CAREFUL! This stummel was different, I'll get to that in a second, but the idea is to put something rod like into the mortise and chuck that into the lathe to spin it. Apparently the non-business end of the drill you use to cut the mortise will sometimes work (in my case that's not seemed to be tight enough). Perhaps a section of drill stock, or stainless tubing, or anything stiff and strong you have around that will fit snug into the mortise should do the trick. I actually used Delrin, but that's not stiff enough, and caused the face of the shank to dome a little because of too much flex, which I had to clean up latter.

So, that drill rod or whatever is then chucked into the head stock chuck with the stummel on the end sticking out far enough to get a cutting tool into the end of the shank to face it off. You then spin up the stummel (yes, it's scary). I've been using about 500RPMs or so, but it might go a little faster without spinning off, depending on how deep your mortise is cut, and how tight your drill rod fits it. I've also seen it suggested that you can place a live center against the end of the stummel to support it. That would be at the same location as you had used as a guide for drilling the mortise in the first place (that would be a good idea, but I did not try it). You then use a sharp, thin, and stiff cut off tool, positioned such that it can fit between the headstock chuck and the shank and still clear the spinning stummel.

I'm doing this is in a 9x20 metal lathe and using a special cut off tool holder for this. I use that to cut the finest amount of material I can off the face of the shank, right down to the drill bit (or whatever you have holding it into the chuck). You can rough sand it close so you don't have much material to remove. You sure don't want to take off much there as it is somewhat precarious at best.

This stummel is such that I didn't have enough swing over the tool carriage to pull that technique off. It would spin over the bed however, so I spun up the stummel and used a pencil to mark around the shank to get the exact angle I needed on the face relative to the mortise, and then took the stummel off the lathe and sanded that as flat as I could on the disk sander. Then finished it off using the sandpaper captured between the shank and stem trick. Took a little longer, but worked great. It was also a little less scary!

These methods worked, and I think I'll grow more comfortable with them over time, but I'd be real interested in what other folks are doing for this.

Again, I am not recommending the above techniques. They are no doubt dangerous to you and the stummel!

[kbadkar]

Scott,

The technique you describe for squaring the shank isn't that wild. I read about Rad doing this on the forum and I got some pin gauges for that reason, instead of using drill bits or delrin. You can buy 3 or 4 that hover around 5/16" (say .3120, .3125, .3130, .3135) and you should find one that has a snug fit for your mortise bit. Check out McMasterCarr, they sell them individually. Get some for 5/32" too. Only I don't have a metal lathe, so I use a skew chisel and err on the side of concave.

When shaping first and "free drilling" you can use the forstner (carefully of course) to square the shank BEFORE drilling the mortise. It's damned near impossible to do it after the mortise... don't even try.

[KurtHuhn]

You can also use some dollps of quick-cure epoxy on the intersection of your center lines at the front and bottom of the bowl to enable you to help support it with a rotating center in the tailstock - that way you don't get sharp little divots in the wood that need to be sanded out. Amd you can secure the stummel on the pin gauge and tailstock, and not worry about it hurling off into the dark recesses of the shop - or your forehead.

[staffwalker]

quote <When shaping first and "free drilling" you can use the forstner (carefully of course) to square the shank BEFORE drilling the mortise. It's damned near impossible to do it after the mortise... don't even try.>

I solved the problem of drilling using the forstner (at least it works for me) on those rare times when I forget to do so before drilling the mortise. If one uses delrin it is a simple matter to insert the same size delrin into the mortise which acts as a point for the center part of the forstner to bite into. If the delrin is tight the forstner will shave it away as it shaves the wood. If you don't use delrin then turn some ebonite or wood in the sizes you usually use for mortises. After squaring you can remove the insert by drilling with your normal draft hole bit through the insert to the draft hole. I made a hook out of stiff wire and push it through the delrin to pull it out.

bob gilbert

[James Sunderland]

very slick pipe, tight greain and nice lines, for my taste I like a slightly more bent stem near the botton but I know thats just me, I would still be very proud if I made that.

[sethile]

Thanks for all the tips on facing the shank. The pin gauges sound like a perfect solution. I'll get some of those for sure. May give the forstner bit a try on the next one too.

James, I agree, the stem on this is terrible. I hate it. More bend near button, and perhaps more closer into the shank would help too, but I had something else in mind all together--namely, a much more pronounced saddle, and then I sanded into the delrin and had to punt on that. I may try another stem, but this pipe has other issues, so I decided to just move on to the next (now I'm trying another volcano). If I make another stem for this one, it will have an integral tenon so I have plenty of room to get what I was originally after.

[kbadkar]

Now why didn't I think of that, Bob? Man, I could have squared that pre-mortised pipe up, no problemo. This forum rocks... 200 pipe tinkering heads are better than one block head.