Jam's DC

[ADFinlayson]

On 9/8/2022 at 1:43 PM, komodo said:

Only semi-related but while we're at it... a couple days ago I tried to twist the spray nozzle on my pressure washer while I was using it to orient the spray pattern. Of course I know  how much pressure is there, but still don't really equate it with a table saw blade or anything. Sort of like how a weed eater/string trimmer can bounce off your shoe so you don't have that fear of death, but still wonder if it could cut your arm off.

Turns out that a pressure washer can quite efficiently (and quickly) leave a large jagged wound, like a drunken squirrel may have done.

I imagine that must feel like a cut and a burn at the same time, ouchy

[Nicco]

On 9/8/2022 at 8:43 PM, komodo said:

Only semi-related but while we're at it... a couple days ago I tried to twist the spray nozzle on my pressure washer while I was using it to orient the spray pattern. Of course I know  how much pressure is there, but still don't really equate it with a table saw blade or anything. Sort of like how a weed eater/string trimmer can bounce off your shoe so you don't have that fear of death, but still wonder if it could cut your arm off.

Turns out that a pressure washer can quite efficiently (and quickly) leave a large jagged wound, like a drunken squirrel may have done.

Ooft! Ouch! I remember doing similar when I was about 14 or 15 years old. I snuck up on it by putting my finger in front of the jet like you would trying to pressure up a garden hose. 

Didn't get my finger far enough in to go full angry squirrel, but it was one hell of a blister!!

[Akula]

The great binding experience draws to an end!

 

I put a 9mm bearing on a 12mm drill bit, freshly greased and tightened. The router base got modified with a block attached to the underside of one pillar, at the same thickness of the guitar body, to provide a square cut.

 

This setup doesn't account for the depth of cut changing, so I went shallow and re-adjusted the depth a few times around the body. My gramil used on the edge provided an accurate depth line, vaguely seen in this photo because it's right on the join between top and wings. 

 

Sharpened up my chisels and set to the job in hand. Except, as mentioned, the chisel did in fact end up inside my hand at one point. Whoops.

 

The headstock was a little harder to do, as the router is a bit heavy to get stable on a small surface. I went in with a sharp knife and cut through the veneer, then used the gramil for the depth, and finished the cut with the chisels. 

 

Glued 'er in with CA. I used masking tape and rubber bands to hold it down while the glue set - the masking tape gunk got stuck to the sides with superglue and was a total pain to scrape off. 

 

Had a small issue with the binding protruding from the headstock - guess my channels were a touch smaller there, probably due to some subconscious process. That was taken down to flush with sandpaper. 

 

I guess my chisel skills aren't as good as I'd like, because after cleaning it all up I found some gaps. You'd find it hard to get a fingernail in them, but I did manage to stuff some wood glue and dust in there. Not the best solution, but it came out alright.

 

Right onto sanding for the finish. Here's a shot of the thing up to about 180-grit, wetted with metho to show scratches. The back had a few decent dings that needed steaming/sanding - I need to get a patch of carpet to velcro onto the workbench as soon as the body is rough shaped. 

 

I explored a few different options for finishing. My first idea was 2K poly, but I don't have a spray booth or setup. Rattle cans are an option, but they're expensive and I don't have a sufficiently dust-free environment to shoot in. 

Second option was shellac, French-polished to a high sheen. I've never done a French polish before, but after extensive reading I figured it might not be as protective as I'd like the finish to be. This guitar will probably end up going on the road with me, it won't be a home instrument, and I need to know it won't look like crap within a year. 

The last handful of my builds were finished with Danish Oil, and I'm fairly competent with this style of finish. It's still not a particularly hard-wearing finish, though, and it lacks the glossy look I'm aiming for.

 

Therefore, the current plan is this - Danish oil, applied with sandpaper to achieve a nice grain filled smooth surface, then I'll add more and more poly to the mix on subsequent coats. I toyed with this idea on a V-shaped guitar last year, and although that particular project had many issues with the Danish oil interacting with the black stain, the oil-poly mix was a success. I could buff it to a mid sheen, it was hard enough to withstand pick marks, and it still had that oil-feel instead of plastic poly.

Mostly that was a brain-dump to sort out the ideas in my head into an organised manner. But, it also serves the purpose of allowing all you guys to point out any potential issues with my finishing plan. I hate the finishing process - the guitar's 90% done and I just want to put strings on it already! Patience, Jam, patience...

 

 - Jam

 

Edited September 22, 2022 by Akula

[RVA]

That looks amazing!

Edited September 22, 2022 by RVA

[Bizman62]

9 hours ago, Akula said:

Danish oil, applied with sandpaper to achieve a nice grain filled smooth surface, then I'll add more and more poly to the mix on subsequent coats.

That's something I've been wanting to do for quite some time! My main issue with the recipe is that I don't know exactly what "poly" means - the vocabulary seems to change meanings even within the English language spoken in various parts of the World and even more when derived and translated to other languages. Here every clearcoat is "lacquer" - urethane lacquer, alkyd lacquer, oil lacquer, nitrocellulose lacquer... You name it! Which one will best mix with boiled linseed oil and turpentine?

[Akula]

31 minutes ago, Bizman62 said:

That's something I've been wanting to do for quite some time! My main issue with the recipe is that I don't know exactly what "poly" means - the vocabulary seems to change meanings even within the English language spoken in various parts of the World and even more when derived and translated to other languages. Here every clearcoat is "lacquer" - urethane lacquer, alkyd lacquer, oil lacquer, nitrocellulose lacquer... You name it! Which one will best mix with boiled linseed oil and turpentine?

Totally! In this case, I mean "poly" as polyurethane lacquer. Specifically, this stuff. It's meant as a brushed-on or rubbed finish, which is why many people to refer to it as "varnish", adding to the confusion.

 

The Danish Oil I'm using is of the Organoil brand. I suspect it already has about a 1/4 of it's mass as polyurethane, the other 3/4 being boiled linseed oil and mineral spirits, with possibly other elements to add hardness. It's a good product, I've used it in purity on other builds to good effect. For example, I'm currently playing an old build in my kitchen late at night, I'll grab a quick photo:

 

Nice shine, but not shiny enough. And I do notice pick scratches on this guitar more than my others.

 

Therefore, adding more polyurethane to the mix of Danish Oil after the grain filling stages should add a bit more of a protective film on top, and will give me a much more solid material to buff up to a sheen. I'm not expecting a factory-grade mirror finish, hell no, but a guitar like this deserves to be a bit more than dull.

 

  

4 hours ago, RVA said:

That looks amazing!

Thanks man!

 

 

 - Jam

Edited September 22, 2022 by Akula

[Bizman62]

1 minute ago, Akula said:

adding more polyurethane to the mix of Danish Oil after the grain filling stages should add a bit more of a protective film on to

That sounds just like the articles I've read in the Internet about the recipes woodworkers used to know before marketing overran tradition. For what I've learned TruOil is basically Danish Oil, both of which are based on antique recipes containing linseed oil, turpentine and "poly" or "lacquer". The basic recipe is one third each but depending on the purpose the proportions can be changed at will.

I've finished at least one guitar with Crimson's guitar finishing oils which are counter-engineered from TruOil or something similar. It comes in two versions, penetrative and "high build" and I guess we both know what is the difference between those two! Anyhow, the Ovangkol top became quite level and shiny with them. Much more level than your guitar.

Anyhow, now that you've confirmed that oil based polyurethane works with the Danish Oil I feel more confident to mix my own TruestOil!

 

[Akula]

2 minutes ago, Bizman62 said:

That sounds just like the articles I've read in the Internet about the recipes woodworkers used to know before marketing overran tradition. For what I've learned TruOil is basically Danish Oil, both of which are based on antique recipes containing linseed oil, turpentine and "poly" or "lacquer". The basic recipe is one third each but depending on the purpose the proportions can be changed at will.

I've finished at least one guitar with Crimson's guitar finishing oils which are counter-engineered from TruOil or something similar. It comes in two versions, penetrative and "high build" and I guess we both know what is the difference between those two! Anyhow, the Ovangkol top became quite level and shiny with them. Much more level than your guitar.

Anyhow, now that you've confirmed that oil based polyurethane works with the Danish Oil I feel more confident to mix my own TruestOil!

 

Yep, I was having a chat with a lighting technician at work last night about this - he's a cabinet maker by trade - and he kind of chuckled and said that "Whatever Oil" is something people having been cooking up in their workshops for decades. I believed him, the man's long in the tooth by every meaning of the phrase.

Dude, that Ovangkol top came out looking amazing! 

And yeah give it a go with mixing your own. It sounds like that's what Ben from Crimson did, marketed it well, and made good business from it, and there's nothing wrong with that either. I bought a dozen little glass jars from the dollar-store a while ago, they're great for making different mixes of finishes and easy to label. I even add my own stains and tints to them, easy to do since everything's oil based.

 

 - Jam

[Bizman62]

Now that you mentioned your cabinet maker friend, Neil Paskin who's one of your fellow Australians and pretty popular in YouTube used to use something similar as his go-to finish until he found something commercial (probably from a sponsor)

[Akula]

On 9/23/2022 at 4:00 AM, Bizman62 said:

Now that you mentioned your cabinet maker friend, Neil Paskin who's one of your fellow Australians and pretty popular in YouTube used to use something similar as his go-to finish until he found something commercial (probably from a sponsor)

I looked him up - great craftsman. I've followed him on my social medias, because its good to front-load the mindless scrolling with some actually useful and interesting content! Thanks.

 

No pictures today, as all I did was sand up to 360 for the front, back, and neck, 400 for the sides with grain-raising steps in between, and 1000-grit for the binding. I could have scraped the binding, but this binding material was an eBay purchase and seems to invite "skating" with the scraper. I'm halting at these grits for the timber as I'll be grain filling with Danish oil for the finishing phase. Both Tasmanian Blackwood and Walnut are just waiting to soak up that finish... Every time I wet the thing down with metho to search for scratches, I just can't wait to apply the first few coats and watch the figure and grain come to life.

 

Honestly, I'd like to take a moment to outline the things I could have done better with this build. Unusual for a builder to show off their flaws, but the sanding phase always brings out those moments where I wish I'd done a particular task better, and what better way to remember something than to write it down? 

 

• The neck-body-top join has irked me on several builds. I fixed a gap in this join with veneer, and it turned out great, but it's something to work on. More box-making, I believe. Moreover, the hard to reach areas of the neck heel are important to get right on a neck through build, because they are difficult to get later with low grit sandpaper. The "I'll fix it later" approach doesn't work. This build just has some areas right in the cutaways that will definitely show some pockmarks from the router through the finish, and they're nigh impossible to get at.
• Speaking of router-rash, I'll be buying some good decent quality bits and bearings to use on future builds, or at the very least do a new purchase of mid-quality bits before each build. The amount of time I spent trying to sand out burn marks was incredible, and not an efficient use of my limited time in the shop.
• Binding channels. Next time, I'm using a proper routing jig or not at all. The top side looks amazing, but the sides and back definitely had gaps from my chisel work, and needed filling with glue and dust, which will of course be visible. It's not a major concern for me, but others would notice.
• Timber storage and acclimatization was mentioned earlier in this thread, as my top cupped and was recovered with plastic deformation similar to how acoustic sides are bent. This wouldn't have happened if I'd realised the city was in the midst of a biblical flood, and had stored my timber appropriately.
• Fret ends. I tried a new technique on this build by shaping one side of each fret before installation, but shied away from doing both because I was afraid of how accurately I could install them without them shifting side to side and looking out of plumb. Now I realise that if I can accurately measure fret slot spacing, I can accurately shape each individual fret down to size before installing, and tap them sideways if installation goes awry. This will make my fretwork much faster in the future.
• "If you don't look after your guitar, it'll end up covered in dents." Well, I'm not much of a writer of proverbs, but stencil this one onto my headstone. My workbench is a hard-weathered MDF top, and after rough shaping I continued to wrestle the workpiece through all other processes, resulting in an absolute nightmare when it came to finish-sanding. I'll be replacing the benchtop at the earliest convenience, and I'll have a stretch of carpet at the ready to velcro down as soon as any future build is past the stage of shaping. Again, if I am to continue building instruments in any reasonable timeframe (especially with my occupation), I need to cut my efficiency down to size, and this is a way to cut at least five hours off my current build time. Be more bloody careful!

 

These are just my own observations. If you guys have anything to add, I'd love to hear it! I started building guitars in 2009, gave up in 2012, and re-started my habit in 2020, so I have many a tip or trick to absorb.

 

 - Jam

[Akula]

I'll set my Danish Oil in a warm water bath for a few minutes before applying the first coat. The logic behind that is that it raises the viscosity of the fluid and allows for a deep initial penetration into the timber.

 

Applied with a good lint-free rag. The first coat gets a lot of oil, left to soak for twenty minutes, then wiped off. It's easy to see the spots that absorb more oil, because they're left looking dull, which begets them another good slap of finishing product.

 

I hang the guitar from an S-hook rigged from the ceiling of my workshop, allowing me to do the entire guitar at once. Naturally, the maple takes much less oil than the walnut, and the parts with exposed end grain, such as sides, cutaways, and contours all drink a ton of oil, so I stay in the shop for three hours during this crucial step to ensure that: a) every bit of timber gets enough oil saturated into it, and b) no excess oil is left of the surface for long enough to go sticky and tacky. Obviously, this is quite the balancing act. I have five different species of wood involved, and every individual piece of wood is different.

 

Case in point - there's a lovely dark feature on the top, above the bridge pickup, about where the forearm would rest. This little knuckle seems to soak up a bunch of oil upon application, yet then spits it back out for about an hour afterwards. The solution is to take care and have patience. Let it take all it can drink, then clean up afterwards. My impression of Tasmanian Blackwood is one of a very oily timber.

 

What a piece of wood, though!

 

The first stage was to get the wood surface totally inundated with oil. That was a success. The next step will be to grain-fill the walnut and blackwood with the oil-slurry technique. 

 

 - Jam

[ScottR]

On 9/29/2022 at 8:07 AM, Akula said:

What a piece of wood, though!

Amen brother!

The way I've gotten a high shine with Danish oil is to actually make the wood shine first. Sand/polish up to an insanely fine grit like micromesh 12000, and then wipe on the Danish. Let it soak in and then wipe off the excess. Repeat until no areas will soak in any more and then up up that excess and let it dry for a couple of days. No abrasion resistance but man does it look great!

SR

[Akula]

11 hours ago, ScottR said:

The way I've gotten a high shine with Danish oil is to actually make the wood shine first. Sand/polish up to an insanely fine grit like micromesh 12000, and then wipe on the Danish. Let it soak in and then wipe off the excess. Repeat until no areas will soak in any more and then up up that excess and let it dry for a couple of days. No abrasion resistance but man does it look great!

That does make perfect sense - a shiny surface to begin with is the way to go. I'm interested to know what kinds of wood you've done this with? My Tassie Blackwood is very open-pored with a wavy grain, so I had assumed I wouldn't be able to go much higher than about 400 grit, but I'm now kicking myself for not giving it a go anyways.

I'm going up to 600 or 800 with the slurry coats, or even higher until I'm happy with it. After I start adding more polyurethane to the mix I'll go to finer grits again.

 

 - Jam

[Akula]

Onto the slurry coats. The theory behind this, for those unaware, is that while applying the oil with sandpaper with moderate pressure you sand off the exposed fibres of timber into dust which mixes with the oil and then sinks into the grain, creating a flatter surface. I did this three times with 400-grit on the back, top, sides and headstock, leaving the maple alone. There's always a risk of tainting the maple with walnut dust, but a quick hand with a clean rag prevents this.

 

Action shot. I sand in little circles for the first slurry coat, knocking the heads off any fibres silly enough to poke their heads up. The second and third coats at 400-grit get sanded along the grain. 

 

Since this takes longer than simply applying with a cloth, by the time I've sanded dust and oil into the top, sides, back and headstock, it's usually about time to start rubbing off excess oil - or adding more with sandpaper, if the area calls for it. 

 

I leave each coat for at least 24hrs to dry before the next. After three coats of 400, I stepped it up to 600-grit tonight. As seen here, the wavy grain of the top is starting to look nicely sealed and filled, but could do with more flatness. I'll probably go up to 800 before going to the polyurethane coats. This is application number 5 of Danish Oil now, so I think the timber has slake it's thirst by now.

 

 - Jam

 

[ADFinlayson]

Looking great. I use Danish oil on my necks all the time and sand in the slurry coat like that, but I've never thought to warm the oil up first, I'll give that a try. Thanks for the tip.

[Akula]

16 hours ago, ADFinlayson said:

Looking great. I use Danish oil on my necks all the time and sand in the slurry coat like that, but I've never thought to warm the oil up first, I'll give that a try. Thanks for the tip.

Thanks mate. Warming up the oil to lower viscosity is based on thought experiment, I have not actually tested it scientifically... But I figure it's worth the effort, and the fan heater makes the shop a bit more comfortable to work in as well!

 

 - Jam

[ScottR]

On 10/1/2022 at 3:49 AM, Akula said:

That does make perfect sense - a shiny surface to begin with is the way to go. I'm interested to know what kinds of wood you've done this with? My Tassie Blackwood is very open-pored with a wavy grain, so I had assumed I wouldn't be able to go much higher than about 400 grit, but I'm now kicking myself for not giving it a go anyways.

I'm going up to 600 or 800 with the slurry coats, or even higher until I'm happy with it. After I start adding more polyurethane to the mix I'll go to finer grits again.

 

 - Jam

That ol' bear in my avatar pic is pecan with a lot of spalting done exactly the way I described. I've done maple, myrtle, mesquite, mahogany, walnut, ziricote, bocote, ebony and many others the same way. Open grain stuff will polish up nicely too, but it still has the open grain.

SR

[Akula]

I'm up to my poly/oil mix coats now. I've had to two major issues to date, the first being Sydney's ever-biblical weather. We've been raining for days, again, and as a result the humidity has reached 90% and has stayed there. There's supposed to be a period of 70% tomorrow, which will at least allow me to apply another coat with less risk of clouding up, but it's still taking days for each coat to properly dry.

The second issue being that this Blackwood was far more oily than I had anticipated. I really did throw on quite a lot of Danish oil, and coupled with the weather that means I'm not convinced the oil has dried off yet, making me reluctant to seal in that gooiness with a layer of plastic. I've done a coat of oil/poly at 2:1 and another at 3:2, which has the effect of thinning the poly acceptably, but yeah unless this weather starts acting like it's season, I'm going to hold off with application for the time being.

 

To kill some time, I worked on the electronics side of it. I'm using an EMG system, the 81/60 pair, which comes with a volume and tone pot and a nice easy connection hub for their Quick Connect cabling. Unfortunately, I managed to lose my pickup cables along the way, and most places around here charge upwards of ten bucks for a single EMG cable. So I did some research and discovered that these are just Dupont jumper cables, of which I purchased a 40-pack for five dollars on eBay. 

 

This is my first shot at using copper tape for shielding, as opposed to insulated cables or conductive paint, so I made sure to plan it out. I made a paper net of the 3d space of the cavity, and used that to prepare some pre-cut lengths of copper with tabs cut along their edge.

 

That went okay. Also seen here: magnets. Magnets, man.

 

Cocooned the rest of the cavity with tape, and added a run of super glue around the edge to prevent any dog-earing in the future. This will contact the steel cover plate and provide a fairly decent cage against interference. I'm using active pickups, but I drilled a ground wire hole to the bridge to future-proof pickup changing options.

 

 

Let's hope the weather here dries out sometime this century!

 

 - Jam

[Akula]

It's been nearly two weeks since the last lick of oil/poly garnished this guitar, and humidity actually dropped a bit in the last few days! Oil coats are finally dry and cured. I wiped on a bit of straight polyurethane today, and regretted it...

 

Should've thinned out the poly first. I reckon that'll dry up with a bunch of ridges and runs. 

Plan is to thin out the poly with metho and wipe on another coat or two - this poly overcoat will be thin, for sure, but I just need enough thickness to be able to level it with wet sanding. I'll go high with the grit numbers before I start buffing.

 

Ordered a set of Gotoh locking tuners today, and a set of pickup mounting rings. The original idea was to direct mount the pickups, but I had a job on my bench last week which turned me way off to the idea of direct mount. I'm considering building some rings myself out of ebony and binding them with this abalone stuff, but that might be a touch too flashy.

 

 - Jam

[Bizman62]

5 hours ago, Akula said:

I wiped on a bit of straight polyurethane today, and regretted it...

Thanks for telling. I suppose for wiping a bit of oil will help to level the poly. On my Ovangkol build I started with several layers of the thinner mix, about twice a day. The Crimson stuff doesn't seem to smell too badly, I let the guitar hang in the doorway between our living room and my man cave. I then applied the thicker stuff using a stamp size piece of ~1200 sanding felt, wiping the excess off between every layer. I didn't count the layers, I finished when it looked like it. But the amount of oil used was actually surprisingly little! There's still half a bottle of each left and they've been used on some necks as well.

[Akula]

I did a thinned coat of poly about a week ago. This is right after application:

 

I won't drag on about the weather again, I feel like I've spent this whole thread flogging that dead horse. But a week later and it's finally dry... Considering the moment, I think I'll let that be the final coat. I'm going to start wet sanding up to a high grit as soon as I have the time, starting from a fairly high number. That first coat of poly was rather thick so I don't think I'll be in much danger of sanding through it if I'm careful. I'd love to hear from other builders in these humid parts of the world about how to manage finishing in such a climate!

 

My pickup rings arrived in the post, and of course they're a fraction too small for EMG's to fit through, and the mounting holes aren't the right spacing. I pray in the future somebody will buy out all major pickup manufacturing companies and standardise this kind of stuff. The Gotoh tuners aren't black, either, like the rest of the hardware, they're what Gotoh call "Cosmo Black". Ah well, good enough. They are pretty.

 

Hopefully I'm only a few weeks away from final assembly and setup. This is the last guitar I'll be gifting to myself for quite a while, and as excited as I am to bring it into life, I'm also keen to start ordering for the next run of clients. My father taught me not to start another project while the last one is still on the bench, and although that isn't always possible in the world of small business, it's a good ideal to uphold.

 

 - Jam

[henrim]

On 10/26/2022 at 3:51 PM, Akula said:

I'd love to hear from other builders in these humid parts of the world about how to manage finishing in such a climate!

No experience as such as our climate in the Northern Europe is quite the opposite. Although here beside the sea it can be quite humid at times. Anyway, I would probably try to tackle the problem by taking the climate out of the equation by building a simple curing “oven”. Not oven in a sense that you would bake the guitar but some sort of insulated box with a moderate heat source and ventilation to get rid of moisture. I don’t know about your mix but maybe it needs light to cure so the heat source could be an uv lamp. Just thinking, it may not be easy to accomplish an optimal solution. And you don’t want to heat the dimensioned wood much, obviously.

[mistermikev]

looks pretty sharp.  that faux paua binding against that top(dark flamed maple? walnut?).  nice job.

[Crusader]

I noticed your pickup wells are very square and I wondered how you did it. So I scrolled back and found where you said you chisel them out, don't think I've ever seen that before, is there a reason for it, do the pickups you use have square edges?

[Akula]

On 11/2/2022 at 3:38 AM, mistermikev said:

looks pretty sharp.  that faux paua binding against that top(dark flamed maple? walnut?).  nice job.

Thanks mate. It's Tasmanian Blackwood with a flamed figure, lucky find from the local timber yard.

 

21 hours ago, Crusader said:

I noticed your pickup wells are very square and I wondered how you did it. So I scrolled back and found where you said you chisel them out, don't think I've ever seen that before, is there a reason for it, do the pickups you use have square edges?

I'm using EMGs which are fairly squared anyways, and the smallest bearing I have for my router bits is 12mm. Instead of buying a bunch of smaller bits and bearings, I just knocked the corners off dead square with a chisel. The pickups will be mounted on steel rings anyway, so nobody will ever know haha.

 

 - Jam