JCM 800 combo conversion - Better final picture
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JCM 800 combo conversion - Better final picture
After two days at the Dallas guitar show [bought nothing - thought I was safe] I foolishly ventured into a Sam Ash and saw a model 4210 Marshall. More foolish - I plugged into it. I always wanted a JCM 800 head but the aircraft carrier width always turned me off. The store knocked money off the asking price and like a total fool in love with it's tone I took it home. All 56lb of it - yikes.
Head cab time. I found some padauk and began to plan. I decided to make the head with the same geometry as Marshall used - 1" round overs on the leading edges. Instead of plastic corners these will be walnut, the piping maple.
Here are some progress pics - I expect to start planing, shaping and sanding tomorrow.
Russ
Head cab time. I found some padauk and began to plan. I decided to make the head with the same geometry as Marshall used - 1" round overs on the leading edges. Instead of plastic corners these will be walnut, the piping maple.
Here are some progress pics - I expect to start planing, shaping and sanding tomorrow.
Russ
Last edited by Geeze on Tue Jul 07, 2015 2:45 am, edited 2 times in total.
Re: JCM 800 combo conversion - Better final picture
That's going to be gorgeous.
Re: JCM 800 combo conversion - Better final picture
That's going to be gorgeous.
Re: JCM 800 combo conversion - Better final picture
Edge/corner work. After sanding the fingers and corners pieces to a flat plane it was time to start the round over process. Cutting a 45 degree bevel with a table saw was contemplated but screw ups tend to be catastrophic - same for routers. A 1/2" with a hand plane is not all that hard but a 1" was too much. Orbital sander and 80 grit disks to the rescue. Here is the first corner roughed in.
I tried to get some close ups but my camera didn't know what to do with all of the orange but make it neon bright.
Russ
I tried to get some close ups but my camera didn't know what to do with all of the orange but make it neon bright.
Russ
Re: JCM 800 combo conversion - Better final picture
That looks awesome. I wish that I had wood skills. Nice work!
- norburybrook
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Re: JCM 800 combo conversion - Better final picture
Beautiful work there 
Marcus

Marcus
Re: JCM 800 combo conversion - Better final picture
Jealous. That looks amazing!
Re: JCM 800 combo conversion - Better final picture
Geeze,
Did you cut the bottom ply fingers short and put in individual blocks to show paduk finger joints on the bottom of the sides?
The corner blocks are a good idea. Looks good and using harder material gives corner protection if using a softer body wood. I want to remember that trick.
Did you cut the bottom ply fingers short and put in individual blocks to show paduk finger joints on the bottom of the sides?
The corner blocks are a good idea. Looks good and using harder material gives corner protection if using a softer body wood. I want to remember that trick.
- johnnyreece
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- Location: New Castle, IN
Re: JCM 800 combo conversion - Better final picture
Padauk is a beautiful wood. That's what my avatar amp is built from. I like the idea of using something less expensive on the bottom...no one's going to look at it, anyway! 

Re: JCM 800 combo conversion - Better final picture
Thank you for the compliments! I started doing fingers on the bottom ply as it hurts me to 'waste' good wood on the unseen bottom. Plus it is two sets less fingers to cut.
Here is the first slurry sand with 320. I'll work on the face plate tomorrow. I was thinking of leaving the maple 'piping' flat with the face but now I am concocting a blade to shave the bead in and have it stand proud like the normal plastic piping. Some for looks, some as the padauk will stain EVERYTHING.
mhartman - to quote my acoustic building mentor when he is asked how he is able to build such pretty work - 'Cuz I'm willing to fuck shit up on the way!' My professional cabinet building buddies all tell me that the art of wood working isn't perfection but fixing the screw ups in an artful manner. Each project I push the boundaries and use better [and better adjusted] equipment. Find some wood working fools and fall in with them!
Russ
Here is the first slurry sand with 320. I'll work on the face plate tomorrow. I was thinking of leaving the maple 'piping' flat with the face but now I am concocting a blade to shave the bead in and have it stand proud like the normal plastic piping. Some for looks, some as the padauk will stain EVERYTHING.
mhartman - to quote my acoustic building mentor when he is asked how he is able to build such pretty work - 'Cuz I'm willing to fuck shit up on the way!' My professional cabinet building buddies all tell me that the art of wood working isn't perfection but fixing the screw ups in an artful manner. Each project I push the boundaries and use better [and better adjusted] equipment. Find some wood working fools and fall in with them!
Russ
Re: JCM 800 combo conversion - Better final picture
Impressive work
, congratulations. 


Design/Make/Service Musical stuff in Buenos Aires, Argentina, since 1969
Re: JCM 800 combo conversion - Better final picture
God Bless national holidays and days off! Face plate and 'piping' channels cut. Now to cut the bead into the piping and reduce the face plate to 1/2".
Russ
Russ
Re: JCM 800 combo conversion - Better final picture
Finished except for the back plate. The scary part is now I'm contemplating a 4x12 after all of the years running away from them.
Happy 4th!
Russ
Happy 4th!
Russ
Re: JCM 800 combo conversion - Better final picture
Wow! Just wow. That chassis has a big smile on its face now with a cab like that to wear around. Nice job.