To Those Using A Pressure Cooker As A Steam Generator

[SHINE]

I've got my hose (HD brake line, got my needle (veterinarian, for horses etc.), clamps, and got my pressure cooker. Are the people using this setup just clamping the hose directly to the main release valve and cranking the heat? Bringing it to a boil & dropping to a simmer?

I hooked everything up, heated it up, and wasn't getting anything from the needle. I cooled it down, depressurized, and tried blowing through the needle to check for any obstruction. It takes what seems like quite a bit of force—more than the little weighted safety cap would allow (I assume). But maybe that's required to force steam out of the rig and through the needle? I'm just a little anxious about building pressure beyond what the gasket can handle... Was thinking of installing a second release valve and using one for the hose/needle, and one for the regulator, but thinking a little harder about it, the steam would release through the path of least resistance first. Maybe an adjustable valve w/ gauge so I can have some idea of the pressure I've built up and regulate the flow?

Ideas? Tips? Thanks.

[SHINE]

It's funny, when I was worrying about scalding or blowing myself up using the pressure cooker for the first time, I thought, "Why can't I just drill my holes, fill them with water, and jamb my soldering iron in there to boil it and produce steam? All I'll have to do is just rig up a nail or something to mount in the iron as a tip." Then I considered doing the same, only inserting a torch-heated nail, repeating the process as necessary. Interesting to see that it works. Eerie timing.

[SHINE]

Just checked the S. Mac site to buy one. Yeah, I'm definitely going to rig something up for myself and give it a try.

[Mark A. Kane]

I'll let you know how it works. Being a sucker for new tools, I purchased the rod and the Solomon soldering station. I've been needing a new soldering rig for at least a decade so this new tool put me over the top. I do a lot of neck sets and handle the steam mostly without issue. But I've often pondered the idea of dry heat in the course of extracting necks. Seems like a sound concept. I wonder if it has the HP to handle hide glue. Time will tell.

[Mark A. Kane]

Received the copper rod and soldering rig today. In anticipation of its arrival, I prepped an HD28 for neck extraction (separated the FB extension and drilled an access hole) and mounted my Stew Mac neck extractor on the guitar. The tools arrived and I set them up according to the instructions (took about 5 minutes) and heated the rod. I gave it about ten minutes to reach operating temperature and inserted it into the access hole. After 4 minutes I squirted a pipette's worth of water down the hole and reinserted the tool. The water started hissing so I put a little pressure on the extraction screw and manipulated the body side-to-side (the neck was clamped as shown in the video, except unlike in the video my vise is bolted securely to a heavy maple workbench that doesn't move a jot. Makes all the difference). 3 minutes later the neck was out. No drama. From insertion to extraction was 8 minutes tops. The neck came out cleanly and the pocket was equally clean, with the normal amount of glue residue present. I'm impressed. A couple of observations: the tool diameter is .122". The supplied access hole drill bit is .144". Next time I'll drill a smaller. hole. As for scorching, the tool left a scorch mark on the dovetail. I was able to scrape most of it away. I may experiment with a lower temperature next time, but since any scorching is hidden I don't see it as an issue. Overall, this setup has real advantages over my steam setup. The main advantage is, of course, the absence of all the moisture in the neck joint. The pipette's worth was 80% gone when the neck came out. Some of it came out of the access hole as steam. Another advantage is that the process is dead quiet! You can hear the water hiss but that's about it. Lastly, there's no cleanup to speak of. So I'm pretty satisfied. I'm anxious to give a hide glue neck joint a try. If it proves difficult I'll update my post with that info. 

[SHINE]

Thanks for sharing. Sounds like it works as stated. I'm going to play around and try to rig something up that works the same. If that doesn't work out, I'll likely give this tool a try.

[Mark A. Kane]

Okay, after a 10-day hiatus to enjoy a bout with the flu, I extracted another neck today with the heat rod. This time it was a Martin DM with the bolted mortise and tenon. I followed the same procedure as before except I never got a chance to use the pipette of water. The neck came out cleanly in 3 minutes, 20 seconds! No drama, as before. I used a .128" bit instead of the .144" supplied and it worked fine. With the neck securely clamped and the body suspended above the bench to provide working clearance, I started with moderate pressure on the heel via the extraction jig handscrew and after 2 minutes began rocking the body side-to-side very gently. Seconds later the joint gave way easily. No water or steam, no noisy compressor and steam pot. The wood is clean and ready to work right away. Overall, this method is a solid concept I'm quite happy to employ going forward.

[Mark A. Kane]

Extracted another neck but lowered the temperature by 25% to 400 C (one of the nice things about the Solomon unit is the ability to set a specific temperature and hold it. There is an LED within the display that illuminates when power is going to the tool. It cycles on and off to hold the temperature steady).  I applied pressure to the heel via the extraction jig, inserted the tool, then occupied myself with other tasks expecting the process would take more time but stayed close-by to monitor the process. As the joint heated up, I could hear things popping and ticking. The lower temp added about ten minutes to the total time, so around 15 minutes to extract the neck. The joint simply worked itself apart in the last 3 minutes with only about a minutes-worth of manipulating the body side-to-side. Best of all, the rod didn't scorch the wood. Further fun experimentation is in order with respect to time and temperatures. I have to say, this methodology is one of the most satisfying improvements in our trade that has occurred in my time. 

[Mark A. Kane]

Extraction #4. This time it was the Martin "Simple Dovetail w/bolt" but w/o the bolt. This is a 3" straight rather than tapered dovetail. So it's not going to simply pop out when it's loose. It must be worked the entire length of the joint before the neck comes free of the body. This is also referred to as the "pocketed" neck joint, as the heel and fingerboard extension are recessed into milled cutouts in the body. The pocket depth for the extension is about .020". Getting a wide palette blade under the extension without crushing the adjacent, very crushable spruce on either side (and the end, for that matter) is an exercise in patience. In fact, I don't insert the tool under the sides of the extension as it wouldn't take much pressure to crush the top in that area. After careful heating with my heat lamp, I insert the blade under the end only and work it carefully until it's reached all the way as far as it will go. I'll lift the tool occasionally and bend the extension upwards to get an idea of how much extension is still glued down. This approach has been drama free.

The heel pocket is considerably deeper, around .060" which, on the plus side means that the edge of the heel (where it would typically meet the sides) is now hidden and doesn't have to look absolutely perfect the way it does with a traditional dovetail. The downside to this pocket is that you can't pull sandpaper under the heel to effect the change in neck angle. There's just not enough room to maneuver the paper. It must be done via chisel and whatever other method is effective. I've found that judicious and considered use of the Dremel is helpful, along with super-careful planning and forethought with respect to the amount of material to be removed. The advantage of having the ability to use a bolt for test-fitting this joint is incalculable.

As to the heat stick, this joint took about 10 minutes of heat to loosen, but another 5 minutes of upward pressure on the heel via the neck extraction jig to slip the neck from its moorings. Once it was free, the rest was by the book, which is to say like the previous three necks extracted with the stick, there was very little cleanup to do and I could go to work on fitting the neck right away. No moisture to deal with, no swelling etc. This thing is a winner.

Still waiting on the first hide glue joint...

[Paul Breen]

Mark, thanks for your updates, I ordered one for my WES51. The price and StewMac shipping fee is a bit annoying but it's only expensive once and from your descriptions, this will be a useful tool.

[Walter W Wright]

i got one coming, and an old harmony waiting for it, so that'll be (as i understand it) our test of a hot hide glue joint with the heatstick!

i expect that i'll need to pipette in a little water during the process since hide needs both to soften.

[Mark A. Kane]

...and voilà, it presented itself in the form of an early 50's D28 in need of the usual ministrations (neck reset, frets etc). Hide glue everywhere and not a sign of any previous work. By a professional, that is. There was a significant (bordering on the almost obscene) amount of filing to the tops of the first five or so frets executed by the original owner to address, presumably, fret problems. Well and truly executed, as in no life left in them whatsoever. But I digress. I extracted the neck using the Stew Mac stick in the manner described in my previous posts. It took longer to loosen the joint. About three minutes longer. Total time 12 minutes. The hide glue let go as cleanly as anything I've ever seen. It also cleaned up in about half the time required for modern glue. 

Aliphatic resin, check. Hide glue, check. Epoxy? Let's not get crazy. ;)

[Walter W Wright]

man, i'm glad i brought up this heat stick thing around these parts!

i finally dived in with my first reset, also one of those martin "few or no trees were harmed in the making of this guitar" DMs with the bolt in the neck. the guitar was well beat-up and the owner gave me "nothing to lose" permission to give it a shot. i used the pressure cooker/steam method, and it worked, but involved some painful initial steps up the ol' learning curve :(

the pressure cooker/hose/needle setup itself worked fine, but i think i got caught out by the bolt hole in the neck block. it took way too long to get the neck off, i think because the steam was mostly escaping out the hole in the neck block instead of filling up the joint. it separated down at the end of the heel but not up under the fretboard, at least not until after the steam had soaked the whole area and separated a little of the spruce top and the HPL back from the neck block :o

i was able (after a couple weeks of drying) to reassemble everything and eventually get the neck back on, angle corrected and even playing well, but that was a real hassle.

now that i've seen what's under there, a straight mortise and tenon held mostly by the bolt at the bottom and a glued fretboard extension at the top, i can surmise that the right answer would have been to plug that bolt-hole with something to keep the steam inside the joint (tapered wood plug maybe?) and to pull the hose needle up a bit so that the steam was emitted in the middle of the joint instead of near the bottom.

compare that to your 3 minutes with no water experience with the heatstick and this starts to look like a no-brainer, it might be my first and last steam-removal of a neck!