dillon francis oberholzer Dillon Francis oberholzer dillonfrancisoberholzer@gmail.com

Dillon Francis

Custom Design - Manufacturing - Management

GRP & Composite Yacht Construction




Preparing  the final touches prior to laminating. In this case the part was infused using negative vacuum to draw the epoxy into the foam core and laminate schedule.


This is a specialized area and an integral part of boat and component manufacture. I have been working with mold production one way or another all my life .

Preparation is key. Budgets and forecasting is part of the process. Working as a team with designers, company owners, fabrication - laminating staff whilst building your library are all necessary to ensure a happy client. 

Great progress has been made in the mold manufacture industry over the last ten years. I started out using jigs and frames. The last molds I used were CAD cut with a five axis head.  

Regardless of the mold manufacturing technique or system the lay up of the part is basically broken up into three distinct groups.  

1. Manual lamination.

2. Pre-Pregnated.

3. Infusion or vacuum forming.



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Plug Preparation


Plug preparation is the first step in Tool Making

If special care is taken in the positive or plug preparation you will have many, many more tools to work with.

Most boat manufacturing companies are located in remote areas where space is cheaper as all these parts need to be stored.

One of the biggest problems many small boat builders have is the running overheads and property taxes.   



Always nice to see a perfect part. The tool was cleaned and polished for this photograph. We never get a part out of a tool without a few adhesion points. 

I have worked with many companies around the world as a sub contractor. Either on whole tool manufacture and design or as a specialist for seals or flanges. Tool preparation and cleaning truly is the key to a successful company.

Line management spends more time on material evaluation and production quality than anything else. 

Most glitches with layup schedules are calculated through the design department and sea trials. The experienced boat builder will know instinctively where the flaws in the laminate scheduling is prior to manufacture .

Ordering a tool


Sometimes it is quicker and faster to just order a tool from a mold manufacturer than have in house staff make the tool for you.

Tools can be time consuming to make and costly. Today with CAD and 3-5 axis machines available both the plugs( positive forms) and the tools can be ordered and if your relationship with your sub contractor is  healthy you can rely on his judgement to provide a perfect tool for the production line.

Keeping the floor line operating at a constant speed is always a "bottom line" problem. 

Finally a pretty Pic.


Ordering Parts

Here I was only responsible for the swim platform manufacture as an ad on part.

However, the part came out pretty close to the original gel coat color. We had 150 of these to make.

Subbing out part or pieces to small companies or subcontractors like me can help larger companies when they are pressed for space or time on the production line.


Vacuum Pressing


Not my favorite form of GRP production.

Personally, for the fuss and hassele, I find for a small part like this that hand lay up is quicker and with the right training the laminator can lay-up  three to four parts in the time it take to make one this way.

But, every company owner or floor manager has his own way of doing something.

We all get set in our ways and get used to a process. Far be it for me to tell someone how to run their business.

The perfect Small part shop


Having your shop set up for manufacturing part by size is really important. 

To get a crew to work both together and individually on a piece basis is the ideal for a company but very often the feeding tubes are connected and one mistake by one of the production crew can hold up the entire production line.

Here, I was called in to re-set the feed and vacuum lines to obviate the issue.

A very nicely run business. Great owners with a progressive mindset.




Carbon can be a little irritating at first but once you get the feel of it it's a very forgiving material.

Strengths and laminate schedules will vary with the components you are manufacturing.

There is a mountain of literature you can read on different techniques to make the ultimate part. 

 My advise is keep it simple. Balance your laminate schedule and keep the weave of the cloth in the orientation of the tensile load. 

 Use standard bi or tri-axel cloth in between or have your supplier stitch up a laminate for your specific part whether it be a mast boom or structural member. 


Deck Fabrication / Farr 40 Capetown


I had the fortune of obtaining a Farr 40 tool set as well as a Muira mold set.

This was back in 2000 

 Here we made a support frame for the deck mold and created the tool . Only one part was made  for a single order prior to my return to the USA where I worked for Roballo Boats in Fort Lauderdale, Florida.

Having your workshop well set up helps even if it is only for a one off .

Prep lamination after hull fabrication

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Once the hull has been made you need to laminate the ties for the sole, floor as well as bulkheads and or chain plate reinforcements, etc where necessary.

 Having a suspended gantry helps with cleanliness. 

All boat manufacturing goes through this process in one form or another as the parts all need to be tied in. 

We try to think of the ultimate part that can just be glued together but invariably on larger projects there are places and parts that need additional lamination.