Thinking of building an amp kit

redir · #1 11-09-2020, 11:43 AM

Anyone done this before? Especially if you have built from Mojo Tone. I'm wondering what the level of difficulty is in doing this sort of thing. I've built kit pedals before and never had a problem with those. I've also been building and repairing guitars for 25 plus years which includes a dozen or so electric guitars and bass's. But of course that's nothing like putting an amp together.

Seems like if I just follow the recipie I should be good. Plus I'm friends with an expert amp repair guy in my town too so worse comes to worse.

But if anyone has any experience I'd love to hear it.

This is the one I am thinking highly of:

https://www.mojotone.com/kits/Britis...-Amplifier-Kit

jonfields45 · #2 11-09-2020, 12:08 PM

If you think you can get it done with only a layout diagram and schematic, a Weber kit will likely be much cheaper.

blue · #3 11-09-2020, 12:33 PM

Quote:

Originally Posted by redir

I'm wondering what the level of difficulty is in doing this sort of thing. I've built kit pedals before and never had a problem with those.

You're probably good to go if you go slow, if you've built pedals. Never a bad idea to practice a bit on a breadboard if it's been a while.

I once watched a friend struggle for over an hour to solder a ground wire to the chassis with his normal iron! Ended up using a ring terminal. So look into that in detail when the time comes to avoid frustration if you don't want to have to buy a large/heavy duty iron for a one time usage. Or I guess you could borrow one from your friend?

Others may have had no problem. I only have the one experience.

Dru Edwards · #4 11-09-2020, 03:10 PM

I almost bought a Trinity amp kit 6 or 7 years ago (Ontario, Canada) but didn't think I'd have the time to build it. They even have a forum where you can ask questions on the build. I just checked the website for the first time in years ... you have me thinking

.

Sounds like you know how to solder and how to following instructions so why not go for it. That 18w TMB kit is basically the same thing I would build myself.

redir · #5 11-09-2020, 03:14 PM

YEah the 18 watters sound great. I like the idea of the original with the Vibrato but having the master volume is the way to go I think. 18 watts can be plenty loud. I know my 22 watt Mesa is.

This is the soldering iron I currently have: https://www.stewmac.com/luthier-tool...UaAta_EALw_wcB

"It heats to 400 degrees F (204 degrees C), and at 40 watts, is a step above short-lived 15-30 watt megamart irons. "

Hopefully that will be enough but if not then I will consider the alternative. I think I have an older 50 watt one too.

IT seems like the Mojo and the Weber are about the same price. I've bought some things from Mojo in the past and have installed some of their pickups for customers and they sound great. Plus they are just a few hours south of me in North Carolina so I kind of like that too.

jklotz · #6 11-09-2020, 05:25 PM

I've done 3 now. It's a lot of fun! I did 2 Allen amps and a 5e3 from boothill. All 3 came out great. If you can build a pedal kit, you can do an amp kit. Just make sure you understand the safety rules. Remember you are dealing with lethal voltages. I'd recommend getting a kit with step by step instructions for your 1st build. It helps a lot, particularly in the order in which you put the parts together.

Hope this helps.

Marley · #7 11-11-2020, 08:57 AM

Back in April and May I built a 59' 5E3 from a Stew Mac kit. Although I followed some internet advice for a few things, the directions are perfect and incredible. Step by Step. This was my first time soldering and following a diagram. I can probably do another one without the directions and just a diagram now that I have my feet wet. The amp turned out great and worked on the first fire up. It's now my main amp!

redir · #8 11-11-2020, 01:38 PM

Quote:

Originally Posted by Marley

Back in April and May I built a 59' 5E3 from a Stew Mac kit. Although I followed some internet advice for a few things, the directions are perfect and incredible. Step by Step. This was my first time soldering and following a diagram. I can probably do another one without the directions and just a diagram now that I have my feet wet. The amp turned out great and worked on the first fire up. It's now my main amp!

Awesome! The Stew Mac kits are a bit more pricey but they also took the time to create good documentation and offer support from what I understand. With most things you can't go wrong with Stew Mac for sure.

hanknc · #9 11-11-2020, 02:19 PM

Learn electronics soldering!

acoustigoat · #10 11-11-2020, 09:56 PM

I just finished building a Mojotone Champ kit. My previous experience was building a pedal. That's it. It took far longer than the ~4 hours build time described in the kit, but was well worth it.

FWIW, the StewMac kits come from Mojotone so you can save some money by purchasing direct from them. Their directions are pretty good and the kit comes with a big diagram for the wiring.

I would recommend checking out the subforum on TDPRI dedicated to amp building. Those guys saved my bacon when I ran into some problems. The other great resource is Rob Robinette's site where he offers all kinds of tips and background information.

The safety stuff is no joke! Make sure to read everything twice if not three times. You will want to buy or build a capacitor discharge tool and a light bulb limiter for when you are ready to test everything out.

My build was a great learning experience and a lot of fun. Go for it!

MCDEMO1 · #11 11-11-2020, 10:53 PM

Another +1 on the Stew Mac '59 5E3 kit.

Very good components were supplied. Worked first time and sounds great.

I have plenty of soldering experience in building electronics and cabling for industrial control systems, but the good step by step directions for a first time amp builder were appreciated.

I did have to send for another cabinet right off the bat as the speaker mounting studs were way off on the first one I received. Very quick no cost exchange.

Stew Mac also answered some questions right away on some voltage differences I measured on my build against the numbers in their specs checklist.

I'm sure getting a kit direct from MOJO would go well too. I've been really tempted to build their '63 Vibroverb kit to compare the point-to-point wiring against the PCB setup in my early '90s Fender Re-issue.

Good luck in whatever kit you decide on.

rcolosi · #12 11-12-2020, 07:28 AM

Do it! It is ridiculously rewarding. I've been doing the guitar fixing thing for decades and the amp building is a completely different experience. All the kits mentioned are going to be good...you really can't go wrong with any of them. I just built a JCM 800, but from individual parts, just because I wanted some slightly different components and wanted to do it with some mods and it actually saved a fair amount of $$ in the end. The fact that you have an amp guy close by is helpful too. The 2 things i would recommend would be to take a look at Rob Robinette's website for the amp info: it is INVALUABLE. I haven't found a more informative resource than what he provides: https://robrobinette.com/Amp_Stuff.htm
and 2. I would strongly recommend building a light bulb limiter. One mistake can take out a PT or destroy tubes in a flash...no pun intended. It costs about $15 to make one and if you mis-connect something, you'll be glad you had it. Good luck!

clintj · #13 11-12-2020, 10:39 AM

I build amps fairly regularly and have built a few Mojotone kits. The kits are quality, but the documentation is sparse and there's occasionally missing or incorrect parts. They're great about dropping replacements in the mail at no charge. It's always a good idea to verify values with a meter when possible with any kit, just as good practice.

Tube Depot doesn't make a TMB version of the kit you want, but their documentation is top shelf. Clear, accurate, well written instructions, and accompanying videos with tips to help you.

I've also gone through the directions StewMac published, and there's issues not apparent to a beginning or intermediate builder. Wire nuts absolutely do not belong in mobile electronic equipment that's subject to possible rough handling. Safety grounds are often done illegally in their kits (it's a code requirement that they get their own dedicated fastener, not tied together with others on a transformer bolt) and their power cord wiring usually does not meet code either. Just a heads up there. You'll get a working amp, but there's room for improvement in the safety department.

Dru Edwards · #14 11-12-2020, 02:43 PM

Quote:

Originally Posted by clintj

I build amps fairly regularly and have built a few Mojotone kits. The kits are quality, but the documentation is sparse and there's occasionally missing or incorrect parts. They're great about dropping replacements in the mail at no charge. It's always a good idea to verify values with a meter when possible with any kit, just as good practice.

Tube Depot doesn't make a TMB version of the kit you want, but their documentation is top shelf. Clear, accurate, well written instructions, and accompanying videos with tips to help you.

I've also gone through the directions StewMac published, and there's issues not apparent to a beginning or intermediate builder. Wire nuts absolutely do not belong in mobile electronic equipment that's subject to possible rough handling. Safety grounds are often done illegally in their kits (it's a code requirement that they get their own dedicated fastener, not tied together with others on a transformer bolt) and their power cord wiring usually does not meet code either. Just a heads up there. You'll get a working amp, but there's room for improvement in the safety department.

Clint - how you doing? I haven't see you around here recently. I know you've built some fine amps.

clintj · #15 11-12-2020, 02:59 PM

Quote:

Originally Posted by Dru Edwards

Clint - how you doing? I haven't see you around here recently. I know you've built some fine amps.

Oh, not bad. Been laying low on most social media with all the stuff happening this year. Everyone is so short tempered these days. Taking care of the family, riding my mountain bike, playing guitar at home, and working.