5F1 “Champ” Build - Splinters, Sparks and Serious Fun Lie Ahead!

Discussion in 'Shock Brother's DIY Amps' started by intensely calm, Apr 30, 2019.

  1. intensely calm

    intensely calm Tele-Meister

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    Backstory Introduction
    Building (assembling) an amp has been in my mind for a couple of years. I’ve done my best to put off the urge, as I really have no reason to build, nor own another amp. I’m a crappy guitar player, have too many guitars and 2 amps already. I have a full-time job, a teenage son, a couple guitar build projects - way too many projects, a wonderful lady-friend, and a dog who wants my attention but doesn’t like my guitar playing.

    So, after avoiding the inevitable for a long time, and lurking in the shadows here at TDPRI, I finally jumped in the pool.
    All the builds and support here, along with Rob Robinette’s great website full of more information than I can digest, may be to blame for this endeavor. ( Thank you Rob for all the work you’ve done and great collection of - detail! )

    The first step was to determine “what” amp to build. I decided to start in the shallow end of the pool and purchased an 5F1 Champ kit from Boot Hill Amps. Dave at Boot Hill was very responsive and got the kit sent right out. I ripped open the packaging and checked all the components, it appears everything is in there. Then I ordered a Jensen ceramic 8” 4ohm, ordered the Power and Output Transformers from Amp Parts Direct. Next was to order Tubes, which came from TubeDepot. Well packed and reasonably priced it seems.
    But all these components will need a home in which to reside, what to do?
    A finished cabinet is ±$200, plus shipping, unfinished cab ±$135 + shipping. Ouch!
    I decided to make my own cabinet, so I went to Home Depot and Lowes, picked up some Clear (Select) Pine and went to the garage. I haven’t cut box joints in years, I don’t have a dado blade, nor a table saw capable of accepting one. So I opted for the router process. I think it was a good decision in the end.

    I watched few YT videos about cutting finger/box joints as a refresher - started questioning this entire project, but back to the garage I went. My cabinet build is based off the Dualtone Amps dimensioned drawing, but I added 1/2” to the depth of the cabinet. I jokingly reason this is so my butt will fit on the top of the amp. In reality it is still a really small cabinet and the handle won’t be comfortable enough to sit on.

    - Here we go!

    Episode 1 - Building the Champ Combo Cabinet

    Home from the big box hardware store(s) and ready to make sawdust.
    Working from the DuelTone cabinet plan, I measured out the lumber, lopped it to length and ripped it to width.
    I don’t have a big table saw, just a very old but reliable bench saw. It actual fits directly under my bench when not in use.

    01-Chopping-Wood.jpg

    After cutting enough lumber to complete 3 cabinets, I set up my makeshift router table and assembled a jig to help cut box joints.
    Using a 1/2” spiral up-cut router bit, I stepped through cutting one slot after another.
    Initial setup took a little time, but once I had the “tooth” spacing set right the cutting went very well.

    02-Routing-Box-Joints.jpg

    The box joints are snug, but not so tight that glue-up would be a problem. If the joint is too tight, the glue can swell the wood a bit and make life miserable.

    03-Silly-Clamping.jpg

    Even though I have enough clamps for this kind of job, I overbooked myself and the clamps I needed were busy on another task, that figures. So, I grabbed some tie-downs out of my truck and improvised a solution. I probably should have just waited an hour and used my clamps, but I was impatient.

    04-Sanding-Cab-Edges.jpg

    The boards and box joints were all cut just a little proud to allow the teeth to protrude just a little when assembled. After the glue dried, I sanded the protruding joints flush.

    05-Routing-Chassis-Control-Cutout.jpg

    I measured for the chassis control opening, then did my rough cut to remove the excess material followed by a quick template routing to clean up the opening. I had thought about cutting this out before I glued the box together, but decided I should wait until afterwards so I could be more - accurate - ?
    Maybe on the next one I’ll cut the cavity recess then glue the box together, or I’ll forget to.

    06-Front-Face-Angle-Cut.jpg

    Next was to cut the front slope of the cabinet by sliding the box through the table saw on the crosscut sled. I did this for the sides, top and bottom pieces to get that magical tilt-back angle - whatever it is - about 1” of difference top to bottom. Worked quite well.

    07-Front-Dado-Route.jpg

    Made a little routing template to cutaway a trough, or dado of sorts, for the horizontal speaker baffle mounting strips. Not sure what to call those pieces.

    08-Gluein-Baffle-Crossbraces.jpg

    09-Roundover-N-Sand.jpg

    After the glue dried, it was time to round-over the exterior edges. I used a 1/2” radius router bit, my portable router tabletop and a 30 gallon trash can as a base. First class equipment!
    Did a little pre-finish sanding just to convince myself I was nearing the end.

    10-Speaker-KO-Route.jpg

    With the base cabinet nearly done, I cut the speaker baffle and back panels to size. Followed that by setting up a simple little circle cutting pivot to use with the router. First, find the center point of the speaker opening, drill a small pilot hole at that point, then slide the pilot hole over a pivot pin which is 3.5” from pin center to outside of the router bit. I set the bit slightly deeper than the 1/4” thickness of the baffle material and basically plunged through the material and slowly spun the baffle on the pivot. Perfect cutout. One down, two more to go!

    Test fit all the panels and then wrapped up the day.

    Next I'll be attaching the loose parts.
     
    Last edited: May 1, 2019
  2. Urshurak776

    Urshurak776 Tele-Holic

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    Nice job! Looking forward to seeing the finished project.
     
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  3. Bill Moore

    Bill Moore Tele-Afflicted Silver Supporter

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    I'm jealous of folks who have the "correct" tools! (And the ability to use them!)
     
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  4. intensely calm

    intensely calm Tele-Meister

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    Episode 2 - Drill, Paint N’ Screw, and a Grab Handle To-Go!

    11-Cabinet-Getting-There.jpg

    Left off with the cabinet looking - not quite ready to make noise, not quite.

    12-Speaker-Mounting-Holes.jpg

    Back to work on the cabinet, started with prepping the speaker mounting points in the baffle. I laid the baffle over a box that was just big enough to allow the speaker to be set in.
    I did my best to align the speaker by rotating it in the hole and marked the location of the mounting points.
    Once the mounting holes were drilled out and counter sunk, I soaked each hole with thin CA (super glue). Then threaded the speaker mounting screws into the holes and added some CA gel to the final 1/4” of threads before final tightening.

    13-Speaker-Baffle.jpg

    Once the CA was set, I gave the face of the baffle a couple coats of flat black paint.

    I believe I failed to mention the addition of the back panel mounting cleats - so it happened before the intermission, or maybe during the intermission. Sorry.

    14-Back-Panels-In-Place.jpg

    The two back panel pieces are roughly 1/8” undersized in width to allow for the fabric covering of the cabinet and the panels.
    Now to measure, mark and drill the mounting holes for the back panels.
    I used 1” #8 oval head stainless screws with stainless finish washers. Before wrapping the cabinet, I’ll wick some thin CA into all the screw holes to petrify the wood a bit. This will help keep the treads from tearing out the wood.

    15-Chassis-Actual-Drill-Points.jpg

    I measured the location for the chassis, marked then double checked my work. By placing the chassis on the cabinet and aligning the mounting holes and my marks, I could verify that my measurements were off by just a little, and I was able to correct the issue before drilling holes.

    Time to add the handle. I had seen a video of a cabinet build and it appeared they had drilled for the handle, then realized the handle would not lay flat. So extra holes were evident in the top of the cabinet.
    With that in mind, I was careful to position the handle, which is not dead center on the top surface, but slightly toward the front. This compensates for the bevel front panel and gives a little space for the control cutout.

    16-Cabinet-Handle.jpg

    I pressed the handle down flat on the top and marked the inner point of the morning hole/slit cutouts.
    This allows the handle to lay flat to the top of the cabinet and also to be pulled upward for carrying. If the mounting tabs are installed too narrow, the handle will remain in an “UP” state. I believe that is what happened in the video I mentioned. Glad I saw that vid, as I may have done the same thing. Hope this all makes sense.

    The center holes mounting bracket holes for the handle only need to be about 1/8” deep, but the outer holes go through the cab top. On the inside of the cabinet, T-nuts are installed into the through-holes.
    The handle and mounts are installed… life is good!

    Wrapped it up by drilling the mounting points of speaker baffle.

    17-Cabinet-PreWrap.jpg

    I really understand why a cabinet costs as much as it does, there is a lot of work involved.

    The fabric and grill cloth just arrived as I write this.
    I wasn’t aware the Tweed fabric is White and Brown, with a yellowish tone “lacquer” coat on one side. Hmm, interesting.

    18-cabinet-cloth.jpg

    19-Tweed-Fabric.jpg

    So, in the next episode I will wrap the cabinet and speaker baffle - WOOHOO - stay tuned!
     
    Last edited: May 2, 2019
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  5. intensely calm

    intensely calm Tele-Meister

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    @Bill Moore ,
    I get what you're saying, and I feel the same way about any number of things - like people who can play the guitar... (I try, but it's not musical).
    I'm a hobbyist woodworker at best, and just try to find ways to accomplish my goals, always learning something new.

    I've been collecting tools for a lot of years, have some good tools and some junk stuff as well. My career(s) have put me in a lot of situations to collect random tools; auto mechanic, auto body repair, rough carpenter, and home owner a number of times.
    Now I'm in marketing = air conditioning... life is good.

    I hope you enjoy the process of this amp build.
    Take care!
     
  6. BigDaddy23

    BigDaddy23 Tele-Holic

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    Well done - and exceptionally well documented!

    Out of interest; how much clearance did u give the baffle to the cabinet (ie for that grill cloth)? I've found 3mm (or~1/8") on each edge (6mm overall) is about right for tolex and Fendery grill cloth. I've not used tweed before so it may well be a touch thicker.

    I find this the most precarious part of the build process. Not so much of an issue with a narrow front cab as u can kind of hide any weird gaps if they are on the Nth and Sth edges, but with an open baffle like on BF/SF cabinet, it has to be spot on.
     
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  7. Bill Moore

    Bill Moore Tele-Afflicted Silver Supporter

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    Well, I'm just a hack, but enjoy building the cabs. I cut several baffles with a jig saw following a center with a piece of wire, or string, no they weren't round. I recently picked up a spiral bit saw with a circle attachment, and found I could screw that up also, (you need to keep the head square)! The great thing is after grill cloth and tolex, most boo boos are hidden!
     
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  8. intensely calm

    intensely calm Tele-Meister

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    @BigDaddy23 , thank you!
    I currently have approximately 1/8" gap allowance (each side) for covering on the panel edges and speaker baffle. Now that I have the tweed fabric on hand, I can double it up and verify if the gap will be enough. I believe it will be however.
    The Grill cloth is some tough stuff, rather rigid so I'll have to double check the clearance there as well.
    Worst case, I'll have to sand a little off a couple edges. At least that's my plan at the moment, reality may differ slightly.
     
    Last edited: May 2, 2019
  9. intensely calm

    intensely calm Tele-Meister

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    The jigsaw is a wonderful tool, i think it gets overlooked a lot today. I use mine all the time, metal, wood, plastic.... just swap out the blade and cut away! Good quality, sharp blades are the real secret. I have plenty of burnt up blades too. lol

    When I did carpenter type work, I was told "do your best, caulk the rest".
    After a while, I just did better work and didn't have to caulk as much, but caulk was my friend for a time.

    Take care!
     
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  10. BigDaddy23

    BigDaddy23 Tele-Holic

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    In my experience with tolex and Fender type grill cloth, the 1/8" gap will be perfect. Please let us know about how you get on gap wise though! It's always useful information.
     
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  11. intensely calm

    intensely calm Tele-Meister

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    Episode 3 - Grill Cloth

    I've had very limited time to work on the cabinet this week, but still finding little things that fit my schedule.

    20_Cut-N-Wrap-SpeakerGrill.jpg

    I purchased some MellowTone Grill Cloth, Burgundy and Beige, and after cutting for this champ build, I have enough for another dozen champs or a handful of larger combo cabinets, and I purchased the smallest piece available too. So I guess I’ll have to build a couple more amps - lol.

    I rolled the grill material out, and placed the speaker baffle to align the pattern. I used some 1.5” tape as a cutting guide all around the baffle. Once cut to size, the grill material was pulled around one of the long edges of the baffle. I took care to make sure the beige pin stripe stayed as straight as possible - and it’s not as easy as I had thought. This material want’s to skew and curl… fun times.

    I stapled the two long edges and pulled equally the two shorter edges, again working to get the vertical weave of the material to stay vertical and in a nice line… There is some wave, but it went well. I’ve seen worse at music stores, and honestly never gave it a second thought.

    21_BurnInMountingHoles.jpg

    Using an “Uncle Doug” trick, I “burned” the mounting holes in the grill material. Since the material is some sort of plastic, or nylon, a heated nail made a very nice hole for the mounting screws.

    22_Grill-Cloth-Outside.jpg

    I trimmed the excess material away from the back of the baffle, leaving just short of 3/4” all around on the back. At the corners, where the material had been cut to wrap around, I used some hot glue to tame the fibers and to seal the overlap of short and long edges together. I don’t think this is necessary, but it did seem to make the baffle look better out of the cabinet.

    I hope to start cutting the Tweed this week, and possibly start the soldering of the turret board.
     
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  12. BigDaddy23

    BigDaddy23 Tele-Holic

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    Looks great, mate! You are really documenting this build well!!

    The only thing that worries me about the tweed style baffles it the 'stud' method for securing the speaker. The chance of the screws spinning when tightening up the speaker is there. Don't ask how I know! Another solution to keep in mind is to go with T-nuts in the face of the baffle (e.g. 5mm) to allow for screw fixing from the internal side. I guess if the baffle is thicker, there is more thread in contact with the timber so the chance is lower, but it still makes me nervous....As they say - once bitten, twice shy!
     
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  13. intensely calm

    intensely calm Tele-Meister

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    @BigDaddy23 , thanks and I agree with your concern about the speaker mounting posts possibly spinning.
    I'm hoping that using CA to petrify the wood holes and adding CA gel to the head and last bit of threads will "bond" the studs to the wood - I hope.

    I was originally going to add a nut to the inside of the baffle to lock the posts in place, then the speaker and finally the speaker mounting nuts. The problem was that adding a locking nut created a "stand-off" effect for the speaker, it wouldn't seat up against the baffle. So, that idea failed immediately.

    Now I may try adding t-nuts on the inside as locking nuts (t-nuts without prongs) and see if they will allow the speaker to seat tightly to the back side of the baffle. This would lock the stud in place, in theory.


    Additional-wood-spacer.jpg

    I had considered just using t-nuts on the face side of the baffle, but didn't want them to be up against the grill cloth... I have since added a 1/4" additional wood ledge around the perimeter of the baffle face - so I could have used t-nuts on the front and the potential problem would've been avoided. I just keep changing my plan.

    Worst case, I have another baffle and I can use the t-nuts on the face side and use screws from the inside as you mentioned. Good to have a back-up plan!
     
    Last edited: May 6, 2019
  14. intensely calm

    intensely calm Tele-Meister

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    Episode 4 - Tweeds Away!

    Never having really given the tweed pattern much thought, I learned the pattern runs from 10 o’clock to 4 o’clock, or from top-left to bottom-right as you look at the panel head on. I kept this in mind as I prepped the cabinet and material.

    23_TweedPatternArrangement.jpg

    I began prepping for the tweed wrapping the other night, after a long day… it was late, but I thought I was on my game.
    As it turned out, I was having simple math problems in my head. It wasn’t all bad, my errors were all adding too much material, rather than cutting too short, so there wasn’t a lot of waste, other than time and repetition of cutting.
    So, after I realized that I was tired, I called it a night.

    A fresh start the next morning, finished my cuts, gathered everything I could imagine needing and knew I’d forget something, but jumped right in anyway.

    I marked up the wooden cabinet with lines for the fabric placement, fabric direction (weave angle) and glue lines. Since I chose to used a spray adhesive to apply the tweed fabric, I knew that there would be sticky overspray - everywhere.
    I taped off every part of the cabinet that wasn’t immediately being worked on. Tape and paper are cheap compared to the time and aggravation of things stuck where they shouldn’t be. I learned that a long time ago, one thing that has stuck with me - no pun intended.

    I started with a side, sprayed adhesive on the back of the fabric, then on the receiving area of the cabinet. I had already drawn some guide/placement lines on the back of the fabric, so placing the cab was rather simple, but still needed to be precise.
    The adhesive I used is 3M Super 77, rather aggressive in bond, but still somewhat workable until you press the parts together firmly.

    24_FirstPanel-Prep.jpg

    As I got started I realized I didn’t have a roller to press the fabric down. Always forget something. I tried to think of what I may have, a rolling pin from the kitchen, a tube of caulk, a piece of PVC pipe…. Oh, I have a mat roller for doing fiberglass - not really the best tool but it worked well. A small tool for a small cabinet!

    It was surprising how quickly I was faced with having to cut and wrap the corners, and by the time I got done it seemed like this cabinet had double the number of corners it actually has. It’s like a bulk of the wrapping time is spent doing corners. Hmm.
    I also realized disorientation was a problem as I encountered the corners. I knew an easy way to fold and cut the corners, but it is not what “Fender” did on the Tweeds. So I had to think a bit. Glad I got some sleep last night.

    25_Tweed_1stpanel.jpg

    Since everything was “sticky” from the adhesive, and I knew I didn’t want to get adhesive on the face of the fabric - I chose to first split the fabric at the corner, then place a piece of painters tape on the “lower” piece of fabric, then lay the “upper” piece over and pull it tight. Using a fresh and very sharp single edge razor blade, I was able to cut through both layers of fabric, then pull away the overlap pieces and neatly fit the corner fabric together.
    I’m not saying these are perfect corners, I really did have trouble determining in what direction the “cut” needed to run. I should have done more study of images before jumping into this, but it was a very good experience.

    26_Tweed_bottompanel.jpg

    After the sides were in place, I moved on to the bottom wrap. It was very straight forward and rather easy. No corners, just wrapping and rolling it down.

    Next came the top, I expected this to be difficult due to the control cavity area.
    I took my time, again covered everything that shouldn’t get adhesive on it, sprayed, gently placed the fabric, verified alignment, removed the tape and paper and began the process of getting the control cavity - resolved.

    27_TopPanelControlCavity.jpg

    I knew there had to be a slit cut for the inside corners of the fabric at the control area, and that a “filler” piece would need to be added below the fabric wrap. I’d seen various ways this had been done, and while what I did may not be Fender standard, it turned out well.
    This isn’t a Fender amp anyway.

    The top panel also introduced a different type of outside corner to address. There are 2 sharp outside corners at the control area, not really like the rounded corners of the rest of the cabinet. Again I gave it a little thought, and jumped in. Take your time, and it all will work out.

    28_BackPanelsBeforeTweed.jpg

    The last panels to work on were the easiest, the back panels.
    I’ve read through a number of buid-threads and it seems these are often the first thing that other people wrap. It would be a good warm up practice piece, but I was concerned that if the fabric thickness my add-up to more than I expected and I would need to adjust the width of the panels. So, I decided I should wrap the panels last, just in case I needed to sand them a bit narrower to get everything to fit.
    As it turned out, my gap was just right, the fabric all fits as it should.

    29_BackPanelCornerMiter.jpg

    The finish cabinet looks really good, I put everything back on to test fit. Now I'll need to determine what "coating" I will use to seal the tweed.
    I also used a heat gun and gently warmed the grill cloth to tighten it up just a little bit. I wasn't really loose, but I think I did get one slight wave to pull a bit straighter, so that was a nice treat.

    30_FinishedTweedAssembledCabinet.jpg

    I'm getting close to the time when I'll need to break out the soldering iron. I better keep studying!
     
    Last edited: May 12, 2019
  15. MasterEvan07

    MasterEvan07 Tele-Meister

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    That's killer!
     
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  16. Paul-T

    Paul-T Tele-Meister

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    looking great. And thanks for the fabric breakdown, I'll be needing that!
     
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  17. robrob

    robrob Poster Extraordinaire Ad Free Member

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    Very nice work and your photographs are of true professional quality. They would look at home in a very nice "How To" book from pre-internet times.
     
  18. intensely calm

    intensely calm Tele-Meister

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    Here we go!

    As if I don't have enough projects, I've prepped a video for the first episode of my Amp Build.

    This video only covers cutting lumber, making box joints, glue-up - being a little unprepared for what I was doing...
    A great deal of the video is at high-speed playback, because cutting lumber and watching glue dry is rather boring.
    Also, there is a great deal of work time not represented, this is only an 8 minute video after all.

    Anyway, I hope you enjoy the first episode. The second episode should be prepped in 3 days or so.



    Yep, that's me.
    I have a lot to learn - video scripting, presentation, filming, lighting, sound, editing.... a long list of things.
    Then there is learning how to "Build an Amp" thrown in there (that should be my focus).
    I think jumped into the deep, deep, deep end of the pool, oh and it appears I haven't really learned to swim - yet.

    Any helpful comments or suggestions are welcome, if you have nothing nice to say... whatever.

    Thanks!
     
    Last edited: May 19, 2019
  19. Paul-T

    Paul-T Tele-Meister

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    very nicely done.

    Did you put a side angle on the cab? Did I miss that bit?
     
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  20. FRANKENJAG

    FRANKENJAG TDPRI Member

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    Well done, sir. I look forward to the next installment.
     
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