Tuesday, October 28, 2008

Carvin Kit Contest

Back in June when I was waiting for the lacquer to dry and wiring the pick guard, I noticed a posting in the Carvin Builder's Forum about a contest for kit builders. The deadline for entry was on September 30th and I got my submission in a week or so ahead of time. For the next three weeks there wasn't much news regarding what was happening with it -- I checked the forum daily, and finally after three weeks they announced the finalists. In a poll thread on the Carvin Guitars forum were two pictures each of the six finalists. My guitar made it!

There's still a few days left to go and I'm in third place. I don't expect to win, but am very happy to have made it this far.

Sunday, August 3, 2008

Setup Part II and PICS

Its been several weeks now since the guitar was first assembled. In my last post I gave the impression that I was done with setup, but nothing could be further from the truth. I tinkered with the setup for a couple of weeks and just now have it the way I like it. Here's what kept me busy... at first the bridge was too high, so I added a shim to the outside edge of the neck pocket in order to raise the headstock relative to the body. This allows the bridge to be lowered a bit while retaining the existing string height. Then I thought it would be nice to have the bridge flush against the body so I added a second shim, but this ruined the tremolo action. During this process I visited the Carvin store in Hollywood to see how the Bolt guitars are setup and finally decided on a single shim. At Carvin the bridges are perfectly parallel to the body and have a 4/64" gap between the body and the underside of the bridge. With a single shim my bridge is at the same height as the factory built Bolt guitars.

In order to shim and un-shim I had to take the neck out. Each time I loosened the strings and lifted the neck out of the pocket as carefully as possible but broke the high E string three out of four times. Lesson learned: get a pack of single gauge strings that match the high E string for the guitar (10s in my case).

I've also been battling fretboard buzz, and have raised the action a little higher than is suggested in Dan Erlewine's "Guitar Player Repair Guide, 3rd Edition". Currently I'm relatively buzz free with the string height set around 0.07 inches on the bass side and about 0.05 on the treble side.

Yesterday I showed off the guitar to my next door neighbor who happens to be a professional bass player. He was blown away by the finish and impressed with the intonation. He even remarked at how well it stays in tune even after some deep dives with the whammy bar. I'm not surprised about this last fact - the guitar has locking tuners, no string trees due to the tilt-back headstock, a graphite nut, and the Wilkinson tremolo. All of these contribute to a great tremolo system.

And now for the moment you've all been waiting for... finish pics.

Friday, July 18, 2008

Assembly and Setup

I was anxious to get the bridge studs in after my trouble with them during the wet sanding and polshing phase. One ReRanch forum member suggested pushing them in with the closed chuck of a drill press, so I went back to my neighbor's house to do so. I got the first stud in and realized that it didn't go in as far as the Carvin directions suggested -- the holes weren't deep enough. We chucked the threaded stud insert into the press, and then pulled the stud out while holding down the body. I called up Carvin and talked to a tech on the phone. He said the problem must be fixed, either by drilling the holes deeper or sanding down the bottom of the studs. Sanding shouldn't be too hard, he said, because the studs are brass which is a pretty soft metal. So I just rubbed the bottom of the studs back and forth across 60 grit sandpaper until the bottom of the bridge height adjustment screw was flush with the bottom of the brass stud. It took about 5 minutes each which included a cooling break - they got pretty hot during the process.

I went back to Bernie's house to press in the studs, and... success!

My next step was to shield the pickup and control cavities with copper tape. I used up the remaining supply from Carvin and then started using the 2 inch tape that I had ordered from Stewart McDonald. The tape extends out to a few of the pickguard screw holes so that the shielding on the underside of the pickguard would be forced into contact with the tape in the cavities.

To mount the neck I spent some time carefully sanding the lacquer buildup in the neck pocket until the neck fit back in.

I installed the spring claw in the rear bridge route and then mounted the bridge. The bridge is held in place by the tension between the height adjustment screws on the front of the body and the force of the springs in the rear.

Here's a picture of the progress so far.

The black wire visible in the control cavity is soldered to the spring claw in the rear and is routed through a small hole between the rear cavity and the control cavity.

All that remained was to mount the jack plate and the pickguard. I used small plastic wire connectors to connect the positive leads from the pickguard wiring to the jack, and to connect all of the grounds (pickguard, spring claw, and jack). This will make it easy to disassemble the guitar without having to desolder, if I ever need to.

For setup I used my copy of Dan Erlewine's "Guitar Player Repair Guide - 3rd Edition". It has lots of information including factory setup specs for Fender and Gibson guitars, as well as the setup specs measured from guitars of well known players such as Hendrix, Claption, SRV, etc. Back in June I purchased the StewMac basic setup toolset, which consists of a straight edge, action gauge, and radius gauges. This set was expensive at around $85.00, and if I were to do it over again would only get the string action gauge. The straight edge is only necessary for determining the amount of neck relief with the strings off. With strings on, the strings themselves can be used as a straight edge by employing a capo at the first fret and holding down a string at the last fret. The radius gauges are not a necessity and can be easily crafted by hand (Dan explains how in his book).

Using the book and tools I checked the neck relief and set the bridge and string saddle heights. The neck is perfectly straight even after putting on the strings, tuning to pitch, and waiting a day. I chose to leave it like that for now, with the option to add relief later as a way to deal with string buzz if necessary. Lastly, I set the intonation using the tuner function of my PODxt-Live pedal.

Thursday, July 17, 2008

Wet Sanding and Polishing

Its now been over a month since spraying the last coat of lacquer. At this point the lacquer is nice and glossy but upon close inspection it has the typical bumpy "orange peel" texture on the surface. The process of wet sanding and polishing will render a glassy smooth "piano finish." I started with 800 grit on the 4th of July and worked to knock down the orange peel until the body was a flat matte surface void of any shiny areas. This took about 4 hours in total, most likely because I was checking my progress more often than necessary.

Here's a picture of my wetsanding setup:

I followed the ReRanch.com Basic Finishing instructions (ReRanch 101) under "Final Polishing" with the following exceptions. Most of these items were suggested by experienced ReRanch forum members.
  • For the recommended pre-soak of the sandpaper, I first pre-cut each sheet into pieces that fit the my sanding block (eraser) and then put each set of grits in a separate glass of water to soak overnight. I labeled the glasses to keep track of the grits. I left the yet-to-be used sandpaper in the glasses for several days until I was finished with the wet sanding.

  • I used a pink pearl eraser as my sanding block.

  • I put plumber's putty in all of the pick guard screw holes, bridge stud holes, neck screw holes, and strap screw holes to prevent water from getting in and expanding the wood.

  • For sanding, I used a bowl of water with a few drops of dish soap. I'd take a fresh piece of paper from the pre-soak glasses and dip it in this bowl of water.

  • I tried not to sand too dry, always dipping the paper/eraser in the bowl to clean the paper and pick up more water, but I tried not to go too overboard getting water everywhere.

  • I checked my progress often by wiping the slurry off with a clean paper towel or rag.

  • I changed the water in the bowl often -- always between grits and sometimes during grits, especially with my starting grit of 800. It took me 4 hours to knock down the orange peel and get rid of all the pinpoint shiny spots. Maybe if I had started with 600 or 400 grit I could have gotten through the orange peel faster. I spent just over an hour each on the other grits.

  • I wiped the body down with naptha and a clean rag between each grit.

  • I sanded with small circular strokes with 800, but then switched to straight back and forth strokes for the other grits, alternating directions with each grit, and finished sanding with the grain at grit 2000.

  • Skipped 1200 because I wanted to finish faster.

As wet sanding progressed, the body got shinier. Here's a picture showing the contrast between the 1500 grit results on the left, and the 2000 grit results on the right. The bright reflection is from the under-the-counter florescent light fixture.

After wet sanding and before the polishing step I was removing the plumber's putty from the various screw holes and managed to pull a chip of lacquer away from the edge of one of the bridge stud holes. I also noticed that the holes had narrowed somewhat from the buildup of lacquer at the edge of the holes. The Carvin instructions say to use a hammer to pound in the studs, and I was worried about doing even more damage to the lacquer during that step.

Based on feedback from the ReRanch forum users, I fixed the lacquer buildup by sanding up and down in the hole with a piece of rolled up sandpaper. Afterwards the edge of the hole didn't look so good, so I applied some leftover dye mixture that I still had on hand from my experiments back in April, and then used a toothpick to apply lacquer to the hole edge . After it dried I lightly wet sanded the areas around the hole again with 1000, 1500 and 2000.

At this point I wanted to see what it would look like polished, so I used a rag and the 3M Finesse-It II compound to hand polish a section on the rear of the body. You can clearly see the reflection of the florescent light fixture here.

Hand polishing is a lot of effort so I did as much as possible with a Stew Mac foam polishing pad in my electric drill, and then finished up by hand polishing the inside of the horns.

Here are the results:

Monday, June 9, 2008

Wiring the pickguard

In my last post I explained the process of spraying the color on. After that I spent the three days spraying three coats of clear lacquer per day, finishing the clear coats on May 27th. The guys on the ReRanch guitar refinishing forum suggest letting it wait 3 days per coat before the final wet-sanding and polishing,and counting the four coats of sanding sealer thats 13 coats or 39 days -- July 5th to be exact. It turns out that I'm out of town on vacation for the two weeks at the end of June so the long wait shouldn't be all that hard -- especially since I've got other things to keep me busy, like wiring the pick guard.

I abandoned my original plan to do stock Strat wiring in favor of the Strat Lover's Strat with tone switching from the Guitar Nuts website. This circuit provides all of the standard Strat switching options and adds the ability to put the bridge pickup in series with whatever other pickups are selected via the 5-way switch, and to put the neck pickup out of phase with the others. The bridge-in-series is activated by pulling out the volume pot, the neck pickup phase is reversed by pulling out the "neck" tone pot. With the tone switching feature the active tone control follows the bridge-in-series on/off switch. In other words, with the bridge-in-series switch off, the "neck" tone control is active. When the bridge-in-series switch is on, the "middle" tone control becomes active.

Here's the schematic for the Strat Lover's Strat (click to enlarge)

I think of the bridge-in-series switch as a rhythm/lead switch. Put the 5-way in neck/middle position for rhythm and adjust the tone using the "neck" tone control. Pull out the bridge-on-switch for lead and adjust the "middle" tone control.

This is probably one of the more complicated wiring setups for a Strat, requiring the use of two push-pull pots for the volume and neck tone controls. The push-pull pots provide the normal control operation for volume or tone and also have separate leads that are switched by pulling the knob out (and pushing it back in). Back in early May I purchased two of these pots and the third tone pot -- all 250K Ohms -- from Stewart MacDonald. The 250K pots are recommended by Seymour Duncan to match the Vintage for Strat pickups, and replace the 500K pots I originally purchased from Carvin.

Step 1 was to add aditional shielding foil to the underside of the pickguard, and mount the pickups, switch and pots.

I think the contrast of the black pickup covers will go well with the dark grain filler in the wood and the ebony fretboard. I've got black knobs to go with the black pickup covers too.

I stared at the circuit diagram for quite some time, comparing it to other diagrams, until I was pretty sure that I knew how it worked. To reduce the amount of thinking required while soldering, I re-drew the diagram to better represent the actual physical layout of the switch and controls.

Each set of six push-pull switch leads are stacked up over the three leads for the pot so space is tight, but I had the foresight to solder everything from "bottom up" to avoid having to use the soldering iron underneath something else that I had already soldered.

I haven't use a soldering iron in over 20 years, but after a few hours I was done. Its not very clean & tidy but I've double checked it with the multimeter and it appears to be wired correctly and working.

I expect it to be early July before I post again. All that remains to do is the final wet sanding and polishing of the body, assembly and setup. I can hardly wait!


Sunday, May 25, 2008

Sanding Sealer and Color

Its been a good week. I progressed through the sanding sealer stage and got the color coat on. The sanding sealer is a high solids lacquer that builds quickly and sands easily. From what I've learned the application of sealer provides two advantages. First, the sealer separates the wood from the color coat, helping to ensuring an even application of color. Also, by block sanding the sealer with fine grit paper, pits and other imperfections are revealed as shiny areas in what should otherwise be a perfectly flat surface. This allows the problems to be found and corrected, further improving the chances and ease of obtaining a glass like finish later on.

I sprayed two fairly heavy coats of Deft sanding sealer and then sanded with 320 grit. There were a few pits over some grain pores, but they were extremely small and I could see that they did have grain filler in them. So I sprayed another two heavy coats and sanded with 400 grit -- luckily I was able to get the body flat without further corrections.

On the Friday night before Memorial Day weekend I built a plastic tent in the garage -- i.e., my "spray booth". I thought it was perfect timing since the final clear coats should be applied over a consecutive three day period. But the lacquer must also be applied when the humidity is low to prevent "blushing", a white film caused by the presence of moisture in lacquer. While I was constructing my spray booth it started raining. I woke up Saturday morning to more rain and 75% humidity. Grrrr.

The weather finally decided to cooperate in the afternoon and I was able to get the color and a coat of clear on. I was a bit nervous about this step, but it turned out not to be a problem. The color was applied using 3/4 of a can of the ReRanch Fender Translucent Blue. I was afraid of getting uneven color -- so I just took it slow and stopped when I thought the color was right. Its actually somewhat darker in real life than it appears in these photos.

While spraying the clear lacquer coats on Sunday I noticed a tiny ding on the front of the body between the bridge route and the arm rest. I must have dinged it at some point after finishing the sanding sealer. To correct this problem I "drop filled" a small amount of regular lacquer into the ding with a small fine-tipped paint brush. Hopefully this will solve the problem, if not I may have to repeat the drop fill procedure.

Friday, May 9, 2008

Grain Filling - Part II

The body is back in reasonable shape by sanding with 100 and up to 220 grit sandpaper. At one point during the process I wiped it down with naphtha and found more scratch marks so I continued sanding. The rear of the body has quite a bit of filler in the pores from my previous attempt. It looks good but the sanding has opened new pores and it needs to be filled again.

For the washcoat I followed Dan Erlewine's advice from my copy of "The Guitar Player Repair Guide" and used one part lacquer to three parts thinner for the washcoat, which I brushed on -- twice. The Deft gloss brushing lacquer and Klean-Strip lacquer thinner don't mix well -- I had to shake the solution every couple of minutes while applying it since it separated out pretty fast.

Thats the thinner on the top. Most of the solids in the lacquer settle to the bottom and form the yellow layer.

I mixed up more filler. Shown below is the Minwax ebony stain, the Bartley's natural paste wood filler (grain filler). The cup in the foreground contains a spoonful of the filler mixed with about 20 drops of the stain.

Here's the body before grain filling...

Shown below is the progress after two coats of the grain filler. The horizontal streaks are from scraping the grain filler off of the surface after it glazes over. Some filler is left on the surface and will get sanded off later.

This is the body after sanding...

And some pics of the body after getting a coat of lacquer to lock in the grain filler...

I'll be applying a translucent blue color coat later in the process...


Monday, May 5, 2008

Grain Filling - Part I

This project is going to take longer than I thought. I made some progress with grain filling but sanded most of it out to correct two problems - blotching on the sides of the body and tool marks revealed by the stain.

The blotching is probably due to a poor washcoat which consisted of only a couple of light misting passes of Deft aerosol lacquer. I've since learned that the best washcoat is a mixture of 1 part lacquer to 3 parts thinner.

The tool marks were not visible until the grain filler was applied. And even though the body looked perfectly smooth before I started, it quickly became obvious that I should have done a thorough sanding first.

The good new is that these problems can be corrected by sanding and a better washcoat.

Here's the rear of the body with the grain filler applied, but before sanding. Note the contrast with the tremolo route which is not grain filled.

This image shows the blotching that occurred on the sides of the body. After sanding this out, I hope to solve the problem with a better washcoat.

Here is the rear contour tummy tuck. Click on the image to view at full resolution and look closely -- you should be able to see circular tool marks revealed by the filler. These weren't visible before the grain filler was applied. I'll be sanding these out before re-applying the filler.

Sunday, April 27, 2008

Finishing Experiments

Ash has very porous grain which must be filled before coating in order to quickly obtain a smooth surface. Without filling the grain, the top coats will just soak into the grain making it difficult to get a glassy finish. I'm using Bartley's Wood Paste Filler and blue dye powder purchased from the Guitar ReRanch.

During the past week I've done some finishing experiments. I managed to get grain filler on the scraps, and some stain and sanding sealer as well. The short version is that I've decided not to stain the wood blue as I attempted in these experiments. Instead, I''ll use dark grain filler to get the high contrast effect and spray a translucent blue color coat after applying the sanding sealer.

Here are the scraps with various stages of grain filler applied.

The two outside pieces on the far left and right have the natural grain filler applied-- it dries translucent so the pieces look very close to the natural wood. The middle three were treated with darkened grain filler -- a mixture of one spoonful natural grain filler to 15 drops of Minwax ebony stain, which produced a very dark gray, almost black filler. The two pieces on the left did not get a wash coat, while the three on the right did (four passes of Deft clear gloss lacquer aerosol). The piece second from the right has been sanded after a single application of grain filler. It exhibits the desired high-contrast grain effect. You can see some blue splotches it -- some of the stain jumped out of the container as I mixed it.

I mixed the blue dye power in lacquer thinner and applied it directly to some of the wood after grain filling and sanding. The three right most pieces below also have a few coats of sanding sealer applied.

Staining the wood after grain filling and sanding didn't work out as well as I had hoped. It appears that the washcoat, the grain filler, or both, interferes with the stain even though the wood was sanded back. The color is uneven next to the grain filled areas - there is a very thin area of natural wood color that follows the grain pattern. I may try this technique with a piece that didn't get a washcoat to see how it works out. The use of lacquer thinner as the solvent also appears to be a problem. Even after several coats of sanding sealer I can see the grain pattern in the surface when viewed at a low angle. The lacquer-thinned staining step appears to have affected the integrity of the grain filler. On the piece that was not stained, the sanding sealer appears perfectly flat.

I might be able to get better results if I had mixed the dye with alcohol instead of lacquer thinner. This is an experiment I will probably try in the future, but for now I've changed my plan to include spraying a blue translucent color coat over the sanding sealer rather than staining the wood directly. The piece above does show the look I'm after, but I want a darker blue and a more even application of color. I could mix and spray the color using the dye powder I have on hand but I'd have to buy a spray gun and a can of regular lacquer (I've got lots of aerosol at the moment). So I opted to order a can of blue translucent aerosol from the ReRanch instead.

My next step will be to apply the darkened grain filler to the body... Check back soon.


Saturday, April 12, 2008

Drilling the neck

I love my neighborhood -- everyone is so friendly and helpful. I don't have a drill press, so I enlisted the help of a neighbor who has one and we drilled the holes in the neck this weekend following the instructions for installing a bolt-on neck at the StewMac website.

The first step was to clamp the neck into position and align the neck to the tremolo screw holes near the bride. We center punched the hole locations on the neck through the holes in the body.

Here we have the screws set through the neck plate and body so we can measure the depth required for the holes in the neck.

Next we set up the drill press so it will only drill to the required depth in the neck, and carefully aligned the bit over the center punch mark. We also spent some time ensuring the drill bit was perpendicular to the plane of the neck.

With the holes drilled, I bolted the neck on and re-checked the alignment. I find that I have to "work" the neck against the body as the screws are tightened to get it into alignment. So far so good.

My neighbor also has a table saw. We used it to cut a piece of scrap ash into small pieces for practicing the finish. We also attempted to cut a thin piece of ash from the board. With the think piece I'd like to replace the truss rod cover (finished just like the body). The thin pieces are still too thick, so I'll have to work them with a plane and sandpaper. Here are the practice pieces mounted to a board for easier handling...

Each of these pieces will be finished using a different technique -- i.e., different combinations of grain filler tints, wash coat (or not), etc. Based on the experiences of finishing these pieces I'll decide on the strategy for finishing the guitar body.

Friday, April 11, 2008


I've begun the process of finishing and assembling a Stratocaster style guitar. Most of the parts have been purchased from Carvin, except for the pickups which are a matched set of Seymour Duncan "Vintage for Strat" flat SSL-2's. The body is swamp ash and I'm considering a finish which involves applying dark grain filler, sanding back, and staining blue prior to the sanding and clear coats. This should give it a "Blue Zebra" look because the grain will become even darker due to the grain filler, while the light areas remain blue due to the subsequent sanding and staining.

The following artist rendition of the final product was created using the virtual guitar application at the USA Custom Guitars web-site.

The parts list also includes a maple neck with a 12" radius ebony fretboard, locking Sperzel tuners,Wilkinson tremolo, white perloid pickguard, black pickup covers and knobs, strap locks, and chrome jack. I plan on a standard Strat wiring stetup.

Here is the body just after it arrived from Carvin:

One of the first challenges will be to drill the holes in the neck. Normally Carvin ships the neck with the holes pre-drilled when you buy a kit. But I originally ordered the neck for another guitar so it doesn't have the holes yet.

I'd like to point out the web sites that have proved helpful so far. The most important is ReRanch.com. This site not only sells products for finishing guitars, but has great 'how to' instructions and an excellent user forum. The free information section at Stewart MacDonald is also very good.

Check back every so often and follow my progress.