Building a Bolger Bobcat (Payson Tiny Cat) catboat from CAD on up

Got my Maslow in about a month ago and set 'er up, went through calibration(s), and started in on a few small ‘starter’ projects. Quickly, however, I decided to start in on a Bolger Bobcat sailboat:

I’ve built small, wooden ‘stitch and glue’ plywood boats before, and this was the first time I wanted to go from fully-digitized plans in CAD to CNC milling.

I recreated the blueprints in AutoCAD Fusion 360, going painstakingly over each measurement and offset to get virtual panels. I then created puzzle joints from freehand splines to ‘cut’ the virtual panels to lay them out on 4x8 plywood sheets.

Taking the plans to g-code in Fusion 360 was not too hard, thanks to the video tutorials out on the Web. From there, it was a matter of cutting the frames, the side, bottom and bilge panels and the other bits and pieces.


I’ve built small, wooden (plywood) boats before, but this was where I wanted to take the full plans, digitize them (via design parameters within AutoCAD Fusion 360) and go from there to CNC milling.

Then came the cutting…:

The Bobcat is now down in the shop, taking shape, with epoxy/sawdust putty in the seams now awaiting sanding and then taping with fiberglass strips:


Oh my god…oh my god…oh my god!! I don’t even know that to say…this is amazing!!!


I am literally speechless



A stitch and glue something is on my Maslow list. You have made my day! :smiley:

Thanks, all! I will keep you updated.

Woops. Forgot to add a few pics for the ‘blueprint’ to digital conversion process!
Here we go:


I have done quite a few stitch and glue projects: a 17’ sailboat, a few kayaks, a stand up paddleboard, and now this 12’ catboat. I, personally, love the method! I cannot say enough about modern epoxy and also about just using plain 'ol fine sawdust from your dust collector for making the seam putty.


The boat build reminds me or Leroy Gibbs in NCIS. At least you don’t have to take out a wall to get the boat out. :slight_smile:

Great work!

I want pictures of it on the water.

Thank you


…already took out part of the wall for a previous boat…! :wink:


You rock! How much do you estimate the materials for the build? I’ve been out on a tall ship and done a bit of sailing with a crew. I was thinking I might want to learn to sail a small boat. This might fit the bill.

Thank you

I’m going to jump the gun - Sonny do you mind if the pictures are used in one of the Bi-weekly updates newsletter?

Thank you

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As the late, great Chris Farley would say…


I hope the other side of the room has garage door on it :slight_smile:


Amazing ! Crazy Good ! Keep it up !


This is a large project using the full cutting size of the maslow, exactly the sort of thing it’s designed for.

What sort of errors are you seeing from your cuts?

This is a perfect example of perfect being the enemy of good enough as so many of us are worrying about the accuracy, while @Sonny_Lacey is not worrying about it, he’s just building it :slight_smile:

Especially after reading the one blog post about a commercial company doing the same sort of thing (with three or more generations of CNC machines, the last of which is expensive enough that he comments that the vaccum hold-down motor costs as much as a decent car), which said that they go through multiple router bits a day and find that the accuracy as the bit deteriorates is enough to affect the fit


Is the door big enough to get this out? :stuck_out_tongue:

This is really awesome, glad it is working out for you.

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Amazing work, it gives me hope my plan for a teardrop trailer won’t be an issue.

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Sure thing @Bee go on and use any pics you like.
As for a materials cost, it’d be something like:

  • plans: $100
  • epoxy and cloth: $400
  • plywood (marine grade Okoume shipped down from Boston): $500
  • spruce, fir for spars: $200
  • various hardwoods: $100
  • brass sheetmetal and various fittings: $200
  • sail (made by Doug Fowler of Ithaca, NY who is one of the best): $750 [alternatively, Sailrite has kits for around $350 if you want to do that bit yourself, but Doug did my last set of sails and I like to support the thing he is good at]

I’m also using lots of scrap pieces here and there from other old projects, etc.
Hope that helps.