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This posting is both an explanation of my rotisserie setup as well as "For Sale" notice of my rotisserie as well. It's an amazing setup but fairly expensive - if no one here wants it, then I'm just going to break it down for parts and sell the stuff I don't want on eBay. However, it seems a shame to not see if someone here might want it.

Actual cost in materials was just over $400 -- but I'll give it to an OLFer for $200 - you'll have to deal with shipping tho'.

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My Thoughts on the Oil Varnish
I got very good results with the oil varnish but did struggle initially with a few issues that are typical of high gloss oil varnish work. If I proceeded further down the path, I feel I could have consistently achieved near flawless work but I find the time and effort necessary to do that level of work with oil varnish not sensible for me from a business perspective. I have since spent a fair amount of money getting a spray setup and will be shooting either nitro or urethane.

I really liked the low toxicity of the oil varnish (I used the Murdoch Uralkyd 500). I also liked the warmth and beauty of the finish and feel that, aesthetically, it is the most beautiful finish available. Tonally, it is superb and equal to French Polish but with much better protection. With a rotisserie setup, the finish lays down perfectly. One thing that I never did with the oil varnish but is something I feel would greatly aid the leveling/buffing process is to apply the last two coats together with the final coat being applied as a "tack coat" -- meaning, apply the last coat while the previous is still tacky to the touch.

In my opinion, a rotisserie is absolutely necessary for oil varnish work and it really does allow you to slather on the coats and never worry about a single drip -- the finish lays down perfectly. The challenge I found with the oil varnish is mostly related to drying over very oily woods (and I use Cocobolo about 75% of the time). It is also very easy to sand through coats at the very end and have a witness line. There are ways to get around these issues but they are time consuming in comparison to spraying nitro or urethane. Ultimately, while I love the oil varnish, I just found it to be taking too much of my time. I'm a perfectionist and unless my work is absolutely flawless, I have a hard time leaving it as is.

If anyone would like to contact me about the oil varnish - feel free to do so; however, check out Bruce Sexauer's schedule as a lot of what I do overlaps with Bruce's method. I personally feel oil varnish is the ideal finish for those without a fully equipped spray booth. If done correctly, it is an astoundingly nice finish for guitars.

Notes on the Design
I constructed the box out of MDF. I wanted it to be heavy to ensure it would never tip over while spinning my guitars. I also finished it with an oil based polyurethane (Home Depot brand). It takes quite a few coats before MDF stops soaking in finish but once it does, it leaves a nice finish. I wanted the box to be easy to clean and wipe down since the oil varnish stays wet for so long and the VFD creates a small air current -- dust is your enemy with an oil varnish finish.

The gearmotor is a sealed/washable 3 phase motor driven by a VFD. The VFD is great as it allows you to dial in the RPM. I believe my gearmotor was a 50 to 60 RPM motor and the VFD let's me set the RPM from pretty much 0 to 100% of the nameplate RPM.

One of my primary goals with the rotisserie setup was to allow easy varnish application for two parts a time. I built paint sticks (guitar holders) from 1" diameter dowels and with my setup, I can easily insert/remove my bodies/necks. I added a threaded bolt and plastic knob so that my paint sticks are held firmly against the hollow aluminum tube. I think the photos will make better sense of this description.

I wasn't able to find an 1.5" diameter (1.25" inside diameter) aluminum pipe with an exact size match for my flange bearings. This is the one component of this design that can be challenging. You could go for a sloppy fit between the aluminum tube and bearings but I wanted a solid fit. I have a local machinist that helps me out on a number projects and he lathe turned the tube to an exact 1.5" diameter which allowed a nice sliding fit with the flange bearings. Aside from this one component, everything else is easily purchased from Amazon, Zoro, or eBay.

This setup is incredibly stable and smooth. You can quickly apply the varnish and then insert into the rotisserie and be off in spinning within a few seconds.

The actual component cost was about $420 (including nuts/bolts, link v-belt, etc, polyurethane, etc ... ). I chose quality components, which add up fast and this is a very rugged setup. I believe I could have saved $100 or so if I spent a month or two looking for all the items on eBay or craigslist.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Hi John,
Thanks for sharing. I remember seeing this video a few months back. You've done a terrific job with your spray setup !!! And your rotisserie is also a more affordable approach.

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Here is a breakdown for anyone that wants to replicate my setup.

1.5" Bore Flange Pillow Block Bearings - ($28 from Amazon)
https://www.amazon.com/gp/product/B01IW ... UTF8&psc=1

TB Wood's QD Bushing - $7
ZORO #: G1120296

TB Wood's V-Belt Pulley - $21
ZORO #: G1809586

TB Wood's V-Belt Pulley - $14
ZORO #: G2469275

Hand Knob - $2
ZORO #: G1733347

3Phase, 60 RPM Gearmotor - $60 from eBay

VFD - $140 from Wolf Automation

MDF, Screws, Paint - $40 from Home Depot

I bought the 1.5" diameter aluminum tube from eBay for around $30 - I did however, need a machinist to accurately size the diameter to fit the flange bearings, which cost me an additional $50. I chose this large size so that I could use a 1.25" dowel for my guitar holder/paint sticks. I find the larger dowel size easier to grip while either brushing or spraying. There are a lot of different attachment methods you could use but I like the ease of just inserting the entire guitar holder into a tube and locking it down.

Lot's of different ways you can work the motor. I chose a 3phase gear motor with about 60RPM and controlled it with a VFD. It's the ideal way to do it but there are other more affordable methods that also work.

Whatever motor you buy, you have to carefully select a VFD that will work for that motor.

Impressively designed and executed as always, Simon.


Sent from my iPhone using Tapatalk

That looks like a well thought out and well built unit you made. Being able to vary the rotisserie speed I'm sure has some advantages.

The VFD is, indeed, quite useful.

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So, I think I'm going to scrap this and sell for parts. Anybody here want the aluminum tube before it goes on eBay ? - I think that is the only thing here that will be a bit challenging to find without some custom machining.

It seems a shame to dismantle it. Wasn't someone using a rotisserie for waterborne finishes?

I seem to remember Woody G mentioning using one.
I just rotate my WB finishes by hand, it dries so quickly unlike some varniches.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.