Tuesday, May 29, 2007

Success is Thick and Juicy!


So it's been a while since I last blogged. Here's why!!

I've been working to complete my most challenging project yet.

A single ended KT88 tube amp. This amp is a variation of the amp schematic from Angela Instruments (www.angela.com) from their how to section - the El34 schematic.

I've changed some parts out as they were called out in the schematic/write-up but it is still essentially the same.

So here's the details of how this project deviates from the schematic:

1. I changed the choke to handle higher current model. Hammond 193M
2. I changed the power transformer to the Universal transformer (also higher current capacity). Hammond 372JX
3. I used a 12ga solid copper ground bus
4. I bypassed the output stage capacitors with a Dayton 1uf polypropylene capacitor.
5. I wired it with Dayton microphone cable on the signal side. (using the shielding as a drain)
6. I used flat speaker wire for the output side.
7. I used Kimber hookup wire (I think it was the 19 ga stuff).
8. I used KT88's from Tube Depot (matched). Currently the Sletvana SED's.
9. I used the Hammond 1627ESE Output Transformer
10. I changed the output cathode resistor to 500 Ohm (with 28 V at the cathode).


Construction Notes:

Since this amp was created from just the write up off of Angela's web site I had to do my own wiring/chassis layout etc. If you're interested in building one - let me know and I can be cajoled into sending you the plans.

Hammond Box - I used a 10x17x4 grey chassis - if you're going to veneer the box - use this one as the black one is textured. If you aren't going to fiddle with veneer then go with the black box. The transformers I used are so heavy the box top caves in (a very little). I choose not to worry about it - if I didn't say anything you wouldn't have noticed.



If you are interested in this project, please email me at (hudsonmiller ampersat gmail period com) and I'll send you the layout/drilling plans for the lid. I didn't do one for the ends so you are on your own there.

Drilling the chassis - use a drill press and a 1 1/8" uni-bit for the tube sockets. Deeply punch the starter holes or the drill bit will walk off center. (it may still). CLAMP your work.


I used a bottom plate and constructed feet out of cleko's - apparently these are used in the airplane industry to clamp sheet metal together while riveting. I love them - no screws - just a $6 clamp tool and the cost of the feet. HIGHLY recommend these.

I used the parts express speaker posts and RCA jacks. Other IEC sockets, switch, and fuse holder come from either PE or Rat Shack. The speaker posts are to long to work in the chassis without a spacer block. Drill holes into it and put the speaker posts through then make your connections to build up the back a little.


Wiring is a 2 evening affair. Especially if you get me to send you the wiring diagram.

The tough part of a project like this is the box work - cause if it doesn't look good it may sound great but will still be garage junk to the wife.

I choose to veneer the box in burled maple on the sides and red mahogany on the top. I would have done the whole thing in maple but I couldn't find a sheet of burl long/wide enough here to bother. The maple is sanded, tack clothed, 1 coat of clear lacquer, tung oil, then 4 more coats of lacquer. I did this order to control the color the tung oil brought out. I found on my sample piece that if I put the oil down first it got a bit dark for my taste.

For the veneer I used the oil based contact cement. As before with the LP#9's I used the scraper method to apply pressure to the veneer. I did get one bubble - which I subsequently pierced and then ironed flat. This has worked so far.

Copper detail is kitchen door hardware - I had to drill out the volume knob to fit the volume pot shaft. - there's also a set screw in the bezel of the knob.

For wiring - I just started with the transformer wiring and built it up from there. The ground bus I'm very pleased with. Initial power on for this amp had NO HUM. at any volume level. Literally - no tweaks since I turned it on for the first time. I'm thrilled. And I am convinced it's because of the ground bus.

All point to point wiring. Where resistors/caps hit more than one pin on the tube socket I left the leads long and ran the lead through both pins and soldered both down to minimize connections.

The output cathode capacitors are twisted together, then a piece of stranded wire connects the cathode resistor to the pair of output capacitors. I ran the strands into the groves of the first twist, soldered the joint - and then trimmed the leads so one capacitor's lead came out one end and the other cap's lead the other. Then hot glued them all together.

As you can see in the wiring - power for the heaters is on one side - signal on the other. Where the heater wiring is close to signal (in or out) I've tried to cross at 90 degree angles and give some vertical separation tool.

It sounds - well - "Thick and Juicy". The bass is fantastic and the mid's and treble are just there - pleasantly present - not in your face. I'm absolutely thrilled with it and it has matched perfectly with my LP#9's. I've stopped using the Champ for now - it's waiting for a pair of low efficiency speakers next winter...

Lessons Learned
1. DO use Angela. Their service is exceptional.
2. Do use your community for questions. Paul Joppa, David Walters, Luther Ward, and Ray P. have been an immense help. See the Bottlehead forum
3. Do get the tube amp bug by buying a Bottlehead kit and get your feet wet.
4. Do call Steve at Angela and ask him a technical question. After/When he shuts you down "I'm not sure you're qualified to do this project" - you will be pissed and vow never to do business with him again. Then, when you realize he's in business to send you parts and DIY means just that DIY - you'll turn your well deserved insult into a new mantra to learn your stuff instead of trying to take the easy way out and ask him. Angela's service is exceptional - be happy with it.
5. Don't try and cut your power switch with a dremel - I've not found a good way to do this without fixing it with bondo.
6. Do use handles on the front/back of the amp - this thing is heavy.
7. Do buy the GZ37 rectifier tube before they are all gone.
8. Do put considerable time into figuring out what your first album will be - it will be a great experience and should be well planned.... ;-) Enjoy!!!

Sunday, January 28, 2007

Too Much Foreplay for a CHAMP

I am currently running a newly completed Bottlehead Extended Foreplay III as a preamp and my newly constructed chipamp as my power stage into the LP#9's. The sound is excellent , however I listen to a fair amount of music as a fairly low volume level. The Extended Foreplay III C4S constant current source leaves behind a hiss - yes you can hear the current passing when it is hooked along side the ultra sensitive chipamp. This is not a problem when playing music at "audiophile" levels but when you are involved in a relationship it's really hard on the "audiophile" ears when the system is at a whisper as all you can focus on is the hiss.

Enter Paul Joppa. PJ is the king of the Bottlehead circuit design(s) and after posting a comment on the bottlehad forum PJ kindly responded with the following suggestion. He said to put a 66kOhm resistor in line with the signal coming from the FPIII just before going into the chip amp, then putting a 22KOhm across the signal input/output. This configuration would yeild a high impedance and about a 12db decrease in signal strength.

I did this initially with carbon comps and it does work. As before with the BSC however it leaves behind a film of yuck on the music. I decided to crack the piggy bank and order some tantalum resistors from Angela and put them in instead. Again - the lesson learned here is that when you want it right the pocket book has to open. The tantalum's did wonders and the music is back to its ultra clear quality, good imaging etc. And NO HISS from the FPIII.

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Sunday, January 14, 2007

Chip Amp - Project Notes

A Chip Amp in a Humidor - The Huma-Champ
Another experiment in Audio Addiction...


The Huma-Champ
So this story begins at http://www.audiosector.com/ and the LM4780 Kit. "Kit" is more like it (emphasis on how kitty the kit is). It is an excellent printed circuit board and parts to put on it. No wire, No enclosure, No Heat sinks, No Mounting Parts, and dam near no Instructions. So the challenge was on. Could I make this diminutive bag of parts come alive.

I don't like to bring my table saw out of the basement. I don't have anywhere to store it, sawdust goes everywhere and I am concerned my neighbours will get pissed. So my first concern was what to stick this amp project in.
One day while walking aimlessly through the mall I saw out of the corner of my eye a Cigar humidor. And the idea was born. I would buy a humidor and use that as the enclosure. I did some surfing on e-bay and found a winner - new glossy black for just over $40.

Next was the heat sink. I don't' do thermal calcs. I studied the LM4780 design guide for days trying to make sense of the math and finally gave up. The calculation said I needed a heat sink with a 1.5 C/W heat transfer (what ever that meant). So then I started cruising the web for heat sinks. I found a vendor that seemed to have a wealth of heat sink material that fell into that category of heat transfer and gave them a call. HA! they asked how many feet I wanted. I only want 2 3" pieces. The guy actually laughed. Then I hear the rapid strokes on his 10 key and I get a blunt - that will be $89 not including shipping. This project was beginning to piss me off.

Back to e-bay - typing in heat sink I land my prey. A fine gentleman is selling heat sink that appears to have turned up on his kitchen table after working second shift at a aluminum extruding shop. He was happy to saw it to size for me and ship for under $30. Now we were talking.



My final stop was on the transformer. Since the "kit" did not include any power transformer, switches, wire etc. I went to Parts Express and picked up one of their torrodial's. As far as sizing goes - the LM4780 wants somewhere in the neighbour hood of 20-28 Volts - pre-rectification. I ended up selecting a 22V, 22V model at 160VA. I think this is working out fine although I'm sure some people will say that I'm underpowered and should have gotten the 22V, 22V at 320VA'ish. Bla Bla. I doubt I'd hear the difference. Besides - I did a little more upgrading.


Enter Mouser - I decided to implement the snubber configuration on the boards from audio sector and I think it worked out well. I purchased some 15,000uF capacitors from Mouser along with the resistors and a couple of orange drops to complete the setup. Although the capacitors don't fit in the top of the board they plug nicely into the underside. This will give me a "nearly dual mono" configuration and the extra juice from the caps will probably make up for the partly anemic transformer.


As you read the web on implementing the LM4780 you will learn about the backside of the chip carrying -35V. It does - insulate against it. I ended up with the sil-pad. That was a lesson learned.
So - here's some pictures of the final Huma-Champ. My first un-kit DIY project. I'm thrilled with it. It sounds wonderful, is dead quite, and packs a punch. Enjoy!
Note the stand off and break in the RCA cable is for a Line level L-Pad to absorb a hiss from my preamp. If you are going to give this project a try. Do so without this correction unless you have the Bottlehead FPIII with the C4S upgrade.
Lessons Learned
Coming from the rear - Figure out how to integrate RCA jacks in the rear. I wired directly to the board but it would be better if I figured out how to put in room for the RCA jacks. Problem is none of them come long enough to simply drill a hole in the rear of the unit. The speaker posts work because I found some that are threaded and are long enough to fit.
Blue Tape - I covered the box in Blue Tape the moment I got it. I believe it helped keep the finish throughout the construction - I'd do it again.
Grounding - This was my first attempt. Seems as though I needed to maybe take some electronics classes. You can see in the photos above that I have a "star" ground fabricated out of a terminal strip. All ground leads go here. It was how I eliminated the buzz.
Fiddle, Spark, Boom - Don't try and diagnose a grounding problem while the unit is on. I bought a new kit from audio sector by trying to see if I could eliminate a ground loop problem before I made the star ground above. Lucky I'm alive. Ruined a speaker driver the in the process.
Tapping the Heat Sink - When tapping very small holes like the #4-40 screws I used to secure the chip to the heat sink I wasted two taps and countless holes. Go SLOW and back out often and clean the tap. I tried to force the tap through the metal and ended up snapping the tap off in the handle.

Baffle Step Correction Clarity!

Ok - so anyone who may have been keeping track of my angst with my LP#9's will have determined that I've been struggling with a rising response. The Martin-King site recommends a baffle step correction circuit. I tried the circuit and was not thrilled.

NOW I'm Thrilled. I replaced the components of the BSC with cement clad wire round resistors and presto - no more film - the highs were still clear and the bass came out just as it should. I also replaced the solen caps. with some dayton polyprop.

So if you want - go for the LP#9 design. It's done. I'm happy.

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Saturday, September 16, 2006

Baffle Babble

So Martin King knows his math - I've installed the recommended baffle step correction for the LP#9's and think it does work - although there's a cost. Think of a baffle step correction as a treble cut - not a bass boost. And cut it does - the LP#9's now sound like every other pair of COTS speakers - spot on - but it's not for me. I've grown accustomed to the sound of the air in the LP#9's without the filter and when I put it in - it kills the presentation - the ambiance - the feeling you are in a venue.

So - I think the verdict is - keep the filter and if I'm listening to rock and roll - leave it in - and if I'm listening to Jazz - out it comes.

So - So - So - SO - SOOO tired of fiddling with the Baffle Step Correction (BSC).

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Friday, August 25, 2006

Cheap Trick

A good friend of mine has me totally pegged. He forces me to try things myself by asserting just how positive he is about something. Playing on my natural tendency to disbelieve, I of course have to try it myself. Then, just as sure as the sun rises, I find he was right. I'll hide his name here by spelling it backwards - bob.

So the most recent edition of "bob" knows - POWER.

Bob has been telling me that for good bass in a system you need two things - Internal volume in the speaker and POWER. So - as you can see by the LP#9's that I now have speaker volume. Lots of it. But on the power side I was convinced that my ultra efficient single drivers and tube amp were quite pleased with each other.

So, the other day on e-bay I see this little NAD amp being sold - using hawking techniques gleaned from Bob I win the auction. For ninety bucks I get a old NAD Power Envelope 2240. The NAD has forty watts of real power with plenty of dynamic headroom. I bring it home and repair it - check the bias and solder together a 100K ohm volume pot onto some old RCA jacks I have lying around.

I hate it when Bob is right. Same volume levels that I typically listen to - guessing about 87-89Db SPL and wow - I can feel the bass - not just hear it. The tube amp was doing a fantastic job of making the music happy but the solid state amp was doing an equally excellent at making the music jump right out of the speakers - it's alive.

So - Bob is right - about the power at least. Problem is, I can tell the difference in the amps. The tube amp wants me to listen to music and the solid state amp makes the music something you "show a friend" and then turn down due to listening fatigue.

The plan right now is to build a Bottlehead Foreplay III with all the trimmings and use it to add the softening that the tubes do and run it through the NAD to amplify a already tube’ed sound. Time will tell - but the tube amp is back plugged in and the NAD is on the shelf - working but cold.

Sunday, August 13, 2006

Visit to the Temple

So - I made a mistake recently. I went to a local audio store called Deja Vu in McLean, VA. This store is a real surprise. It has tubes - amps, preamps, cd players - lots and lots of tubes. Audio Note stuff, their home grown stuff, Manley stuff, Jolida stuff, the list just goes on.

So - Mistake 2. I ask to listen to some of their gear. The young gent - Nick takes me to the Audio Note room. I ask to listen to a 300B (mistake 3). He puts on my favorite CD and I listen - OH MY GOD - is it amazing. He smiles.

Mistake 4 (He tells me what I'm listening to). 10K Audio Note speakers, a 10K Single Ended Amp, a 30K preamp, a 5K CD player... Well out of my price range.

Nick smiles again - He grabs the Vinyl edition of the same CD. Mistake 5 - I laugh that he wants to play vinyl for me.

Mistake 6 - I listen. It sounds a little thinner but there's something intriguing, aluring, real - ah - now I know what dynamic means.

Mistake 7 - I mention this little story to my friend - he laughs at me - he gives me a record player.

Mistake 8 - I've now entered a new garden of unpicked fruit where the only price to admission is more money.....

Friday, August 04, 2006

Breaking In

The LP#9's are sounding great now but I thought I'd share some thoughts on break in and "audiophile" adjectives to describe speakers. My wife has had some great comments over the last several weeks that really do a much better job of describing what it sounds like while I was tuning them than all of the audiophile drivel that is posted on the web.

Audiophile Description - v/s - My Wife’s Description

The drivers are stiff and are very bright -v/s- They sound like an elementary school band!

The box is overstuffed lending to a reduced sound stage with limited presence -v/s- The singer doesn't sound happy!

Poor port tuning has exacerbated driver excursion and has caused near field distortion -v/s- Why do they sound like a boom box?

The bottom end is thin but the imaging is accurate -v/s- where's the bass?

Overall they air and presence is extremely inviting and appears to have a flat response although measurements have not been conducted against a reference system to confirm -v/s- they sound amazing!

Ha - who says she isn't an audiophile.

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Wednesday, August 02, 2006

Love Potion Number Nine –LP #9’s


The Tale

This tale begins with my Bottlehead S.E.X. amp and a friend commenting that now I’ve built an amp maybe I should build some speakers. That one quip has led me down the trail of building these speakers and I hope you get some insight on my project and encourage you to build your own.

I spent countless hours cruising web pages in search for a project that had suitable specs. for my Single Ended eXperimenters (S.E.X.) amp, a speaker design that seemed like I could fit them into my living room without damaging the WAF (Wife Acceptance Factor) too much. Then my search led me to the Fostex website – studying the response curves of their drivers, their excellent assortment of speaker plans etc. Finally, for whatever reason, I chose the Fostex 207E as the driver. In hind sight I suppose the choice was the relatively flat response, the entrance into the beloved 40Hz range, and the electromagnetic shielding that did it for me. After investing in a driver I didn’t want to end up with speakers that put my cordless phone and television on the fritz. With the driver chosen I did a search on the internet for existing plans in hopes of finding a fellow DIY’er that has figured everything out for me.

The speakers and the design began with the information found at http://www.pi.algeriaaudio.com/. Buried in the pages was a Fostex design using the FE207E and the Fostex recommended super tweeter. The design used a pair of book end matched speakers with the driver on the largest side. I was preferential to the look of the Cain-Cain Abby and choose to put the driver on the slanted face instead.

A good friend of mine had me go demo a pair of Von Schweikert speakers which had a rear firing tweeter. I was captivated with the air it gave the room and thought it would be a good idea to try this approach here. After digesting all the web chatter about the bright response from the Fostex drivers – I figured that the rear firing tweeter would help soften the highs from the whizzer cones too.

I attempted to run the totally overwhelming math cad spreadsheets from Martin King’s quarter wave web site and put in my own figures for this design. All in all it was a good lesson in how little I know and how smart others are. Basically the numbers and response curve didn’t seem to suggest that I was doing anything too terrible and off to the drawing board I went.

Not having any real drawing software I ended up using a copy of Autodesk Actrix (their version of Visio) to draw the plans. If you are interested, they can be downloaded here in .jpg (p2). TAKE NOTICE – something’s off with the plans as the original version I thought I was doing had the face of the baffle to the floor – in the as built version it’s cut short of the base. As I recall it was a bit short of making the base so instead of scrapping the otherwise well fit front baffle I trimmed it short. I like the detail but I didn’t correct the plans – or maybe the plans are right on the money for this effect and I measured/cut wrong. Who knows – they are what they are. Costs and Parts Lists are available in excel if you ask.


I have a VERY small work area and even smaller tool storage ability. In all my work area was about 5’x8’ so the notion of saw horses, dust free paint shops, and bunches of clamps etc. was out. To this end I ended up having the MDF cut by a pro and I stuck to assembly. I countersunk and tapped before screwing the panels together, gluing the joints when I was happy with the fit up. Even with that precaution there were of course mistakes. Fear not – BONDO saved the day. One of the rear panels went on about a 1/8” off center – leaving a ridge on one side and a gap on the other. A wood rasp to knock down the big stuff and some bondo and everything was “true enough” to veneer.

In an attempt to increase the WAF I involved my sweetie in picking the veneer. She chose Lacewood – I was pleased. In hind sight I would have been better served to learn on something other than Lacewood. The stuff is brittle, expensive, and itchy. But boy does it finish nice.

In the end the project cost a pretty penny by DIY standards – mostly due to the Lacewood but they turned out well. They sound good – to me. There’s enough choice in tuning them that you should be able to make them sound good to you too. They sounded better when I heard them with a preamp on my system. This hobby is subjective – there is no perfect. If you like an open, crystal clear sharp high end, with a mid that’s emotional but not overbearing then these speakers are for you. If you like to thump your way through your high school and college years they aren’t for you. These speakers are for Jazz and in my opinion they do a superb job with it. Regardless, they appear to be very sensitive to twaeks so you should be able to find a happy place for your own preferences. Between stuffing, port tube length, and baffle step correction circuits you should be able to hit the sweet spot. I’ve ended up naming the speakers LP #9’s – because what could go better with S.E.X. than some love potion??

Thanks to Martin King, Paul Joppa, Terry Cain, and Tim Forman for helping answer my questions. You all are pros.

The following section describes some lessons learned that I hope you find helpful.

Lessons Learned

Screwing – I do recommend screwing - the box together. Fit the case, drill, countersink, screw, unscrew, glue, screw instead of fussing with a thousand clamps. I glued generous amounts of Elmer’s wood glue to both sides of the joint, looking for glue oozing out the sides of the box. After a minute or two to dry you can putty knife off the excess when it’s begun to turn plastic and you’re as clean as a whistle.

Wood Choice – I do recommend using MDF for the first run. The stuff is dusty, chips, cracks, and absorbs water. It sure is inexpensive though and if you’re happy – build the next ones out of plywood. It will also convince you to hone your wood working skills so you never have to use it again.

Baffle Step Correction (BSC) – I ended up not including one – principally because I only have a 2 W amp and the line level correction just stole too much of the ambiance I was striving for. Some day when I get a more powerful tube amp I’ll fiddle around with the speaker level BSC circuit recommended on Martin King’s site but for now I’m pleased without it.

Stuffing – I found the driver to like an empty box. I ended up taking out all the recommend stuffing and leaving only a small piece of polyester (blanket or chair batting) directly behind the driver (about 14” long and the width of the box) and just using a staple gun to secure it.

Room Positioning – I found the speakers to sound the best to me with a toe in so the intersection was about a yard or so in front of my couch. This seemed to take care of the BSC, brightness, and all the other offenses that the Fostex drivers are accused of having.

Speaker Vent Port Tube – I used the 3” precision port. In hindsight I would put it rear firing so there is some coupling of the bass that is produced with the rear walls. I also fiddled around A LOT with the length of the port tube (both in the math cad software and in the actual box) and found that NO extension sounded best to me. When I added any length to the port tube at all the driver lost nearly all the mid/bass and with it out completely the driver sounded sloppy. So I ended up keeping just the front throat from the precision port as the port tube.

Cutting Driver Holes – Well, nobody taught me how to cut holes with a router. So I drilled a pilot hole, stuck in the cutting bit and proceeded to drag the router around the circle I had drawn. This worked for about 4 inches until the bit began to smoke. I switched to my dremel with about the same effect. Finally I ended up hacking the hole out with my jig saw. I shared my toils with friends who are still laughing at me not using a circle cutter for my router and cutting the hole a little bit at a time working my way through the material. I’ll try that next time.

Cutting Driver Holes Too Wide – Well – so much for precision (see section above). I had chosen the hurricane nuts to use on the back side of the panel for putting the mounting machine screws into. I ended up having to bend one side of the hurricane nut up 90 degrees to get the driver into the hole. This worked like a charm and would definitely use the hurricane nut/machine screw combo again.

Internal wire – I selected some Streetwire 14 gauge stranded OFC tinned wire. I think it sounds good. No, this is not an invitation for speaker wire debate. I recommend using the female disconnects you are supposed to. When you are done with your assembly, finishing, and are putting the speakers together for the last time – solder the female plug to the speaker – it makes me feel good that it’s on there nice and tight.

Speaker Cup – Initially I thought that it would be smart to be able to take the super tweeter out of the circuit so I got a speaker cup for bi-wiring. I would not do it again as the L-Pad accomplishes the same thing and it isn’t as chincy. Who really uses bi-wiring anyway.

Spikes – I like the look – although I suspect there would be more bass if the speaker was sitting on the floor. You choose.

Box Stiffening – I ended up only using one dowel to stiffen the “middle” of the sides below the driver. I’m not sure this is worthwhile and may take it out if I do a plywood version some day.

Gauze for Retaining Stuffing – I used the eyelet screws and tied first-aid gauze to retain the stuffing while I was “tuning”. I think I like the idea of an acoustically dead material being used here instead of string. It’s a bigger surface area for the stuffing to have to leak past and is easy to stretch out of the way if you want to put more/less stuffing into the box. I ended up with no additional stuffing other than a small sheet behind the driver – again you choose with your earbuds.

Caulk – Clearly, you must caulk the seams to be sure they are air tight – problem is that I couldn’t see the top inside of the box once assembled, I couldn’t steer my caulk gun from the main driver hole…..I’m open to suggestions here. I ended up cutting a tip off a Ziploc baggie filled with caulk and hand mashing the caulk as high up as I could reach. My guess is there’s a glob of caulk stuck to the top of the box stalactite style. It’s a trade secret and I’ll call it’s the Half Assed Touch of Magic (HATM) that must make these speakers sound so good to me.

Box Material – Like I mentioned before I used MDF. I think next time I’ll use plywood. No, I will use plywood because MDF is made by the devil and sucks more than the Sahara in summer. Also, speakers like Audio Note and Cain-Cain aren’t made out of MDF – I figure they may have some clue about this that I don’t have.

Veneering – I enjoyed veneering. I used water cleanup contact cement called Weldwood and got a foam roller to put it on. I used an excess block of wood with the edge sanded a little bit to round it off as the scraping tool and it seemed to work fine – until I got to the top/bottom edge where I lost track of where the underlying box stopped but the oversized sheet of veneer continued and – CRUNCH – I rolled the veneer off the top and folded it over – leaving a splintered wreck in it’s wake. LESSON LEARNED – full scale practice on cheaper veneer. Next time I will go ahead and press like a son-of–a-bitch and leave the last 4 inches or so just pressed down with just my fingers then >>>Invest in a hand held router with a veneer trim bit (thanks to Steve). This tool ROCKS. You simply drag it around the edge and bingo – perfect edge just waiting for a quick sand. Same goes for finding the holes for the drivers after you are done veneering. Just tap with your fingers until you find the void, cut an X with your utility Knife stick the router bit in the hole, turn it on, drag it to the side and around you go. Presto perfect! To find the holes for the machine screws you may want to make a template of the layout before you veneer so you can use a hand drill to re-drill through the veneer.

Bondo – If MDF is made by satanBondo is God’s answer. Use it instead of wood filler – it’s faster, smoother, can be sanded out if you screw it up and re-done. Thanks Steve L. for the bondo suggestion.

Finishing – I used tung oil but I think Lacewood wants a high gloss – with less than perfect sanding to start due to the grain and lots of coats with sanding between. Next time – more gloss, more sanding.

Dowels – I didn’t want to spend another penny on more dowel just for veneering so I improvised a set of “tent cards” fabricated out of photo enlargement sleeves. I think any glossy cardboard could be used instead. This worked perfectly. Once the contact cement has dried for the recommended 40 minutes or so just lay them out and then begin to place the sheet of veneer over the work and then pull them out one at a time.

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