Pros and cons of creating a wood template?

[plectrudis]

I'm a former lurker who has starting the serious planning--as opposed to the tentative daydreaming--phase of building a teardrop, and I noticed that a lot of folks use a wooden template. I had been planning to make/buy a paper template, trace it onto my exterior plywood, and start cutting things, but now I'm wondering if I'm missing an important step.

Why make a wooden template? Is it a best practice kind of think among carpenters, like the way dressmakers make mockups of their big projects in cheap fabric before they start tearing into the silk and satin? To troubleshoot and to verify their plans? Or other reasons?

And as a cash-flow-sensitive newbie to woodworking, is this something I really need to do? How important is it?

Thanks!

[Woodbutcher]

When building my trailers I prefer to start with a 1/4" pattern piece. I start with the full size sheet of plywood and draw out everything I plan to do. Draw in the roof spars, planning where the hatch hinge goes and the vent fan. Draw the door in relation to the axle and wheel. Figure where the fender goes. Draw in where the galley cabinets and interior cabinets will go. Basically I make a full size blue print. For me, the most helpful part is getting the profile just right. Looking at a full size pattern makes life easier. Plus you can then trace the pattern out onto your sides if using 3/4'' plywood. Trace the pattern out on the side and cut outside the line about an 1/8th inch. Clamp the pattern to the side. Then use a router with a straight bit and bearing on it to follow the pattern and cut your side flush with the pattern. Use the pattern to run the bearing on to make your finish cut back to the line. Repeat on the second side and you will have 2 perfectly matched sides. Others may do things differently, but this works well for me.

[pohukai]

I built mine without a wood template and didn't have any issues. After seeing how people used the wood template, it looked like a lot of extra work without a significant benefit over someone that just takes their time. I, did however create a cardboard mock up of the profile mainly to verify the dimensions would suit my needs; door placement, head room, etc

I did everything in google sketch up, so without that, I would have made a wood template. I made A LOT OF ERRORS in google sketch up before I cut any wood.

[H.A.]

I dont see a wooden template of much value unless its to make accurate multiples.
(not the same as a jig, or fixture what allows assembly)
But maybe helpful in concept seeking where one just wants to see a full size mock-up or such.
Its alot more work & expense.Of course some folks are better at envisioning something, then building it. While others need designs, prototypes, CAD & so on...

[aggie79]

When building my trailers I prefer to start with a 1/4" pattern piece. I start with the full size sheet of plywood and draw out everything I plan to do. Draw in the roof spars, planning where the hatch hinge goes and the vent fan. Draw the door in relation to the axle and wheel. Figure where the fender goes. Draw in where the galley cabinets and interior cabinets will go. Basically I make a full size blue print. For me, the most helpful part is getting the profile just right. Looking at a full size pattern makes life easier. Plus you can then trace the pattern out onto your sides if using 3/4'' plywood. Trace the pattern out on the side and cut outside the line about an 1/8th inch. Clamp the pattern to the side. Then use a router with a straight bit and bearing on it to follow the pattern and cut your side flush with the pattern. Use the pattern to run the bearing on to make your finish cut back to the line. Repeat on the second side and you will have 2 perfectly matched sides. Others may do things differently, but this works well for me.

I did the same but instead of plywood I used 1/4" MDF. I think I paid about $16 for a sheet of 4' x 10'.



In addition to using the template for the sidewalls, I used the template to cut the "ribs" for my galley hatch and the sidewall aluminum.

[tony.latham]

I'm a huge fan of building a template first.

Now, I'm one that builds with sandwiched walls, and perhaps those that build walls out of a single thickness of plywood don't have much use for them. When building sandwiched walls –using plywood for the internals– I use the template to create 2 interior plys, 2 exterior plys, 2 plywood "internals", and 2 aluminum skins. Well worth scarfing two sheets of 1/4" ply together and using it to lay out your door location, bulkhead locations, spar ledge and a few other locations that I can't think of right now.

Here's the wife working on the "internal" plywood for a shandwiched wall. I'm fairly certain she's cutting two out at a time. The pattern is leaning on the house.



You can see where the fore and aft bulkhead mortises have been routed into the internal –and of course the pattern was used as a router template. (Those holes were used to clamp the plywood together to stretch it to 10' BTW.)

Cons? Takes another four hours and runs up $44 for your build. But throw the four hours out because if your making sandwiched walls (and skinning) it'll save you lots of time.

T

[skinnedknuckles]

I used a template made out of 1/4" luan. First I drew the profile that I thought that I wanted making space for cabinets and such I propped it up on my deck and stood back to see if it was exactly as I wanted which it was not and made changes to the profile and the placement of cabinets and walls. Then I cut it out , sanded the edges smooth and routed the sides out of plywood. They are exactly the same size and the placement of walls and cabinets are in the same place which makes it very easy to keep things square and in the right spots. The template acted as the only plan that I had for my camper. It might cost a bit more to do it this way but for me it saved me a lot of time.
Have fun,
Paul

[plectrudis]

Thanks, all--you've given me a lot of food for thought.

I wasn't planning on using the sandwich method, so I'm not sure that a wood template is as much of a priority for me--I was thinking of using 1x2 poplar studs with a 1/2" plywood exterior. (Is "studs" the right word on a teardrop? You know what I mean, anyway.) On the other hand, I'll be using a jigsaw and router for the first time ever on this project, and, to Paul's point, a template would give me the chance to practice on cheap materials. So I'm still undecided, now I'm undecided in a much more informed way.

In any case, Woodbutcher, H.A., pohukai, and Tony make a very compelling case for how detailed my template--wood or paper--should be. I had just planned to use it for the profile, but it definitely makes sense to include the shelves, doors, & windows to test my plans.

I am using SketchUp, pohukai (as of yesterday, thanks to Dan L's wonderful tutorial https://www.youtube.com/watch?v=r4TKpcjJ6h0&index=1&list=PLE232575796E3DB49 on youtube), but I what I see on the screen and how it feels in real life will probably be two different things...

Tom, I've just started reading your build journal (I'm up to Sept 7, '07)--I've been enjoying your attention to detail and willingness to experiment. I'm delighted to meet you! Your post reminded me of another question--you used MDF for your skeleton--why? Is it cheaper than comparable plywood? And if so, would it hold up better or worse than plywood in the case of a leak? BTW, I live just outside of Austin so I feel your pain, slogging away in those 100F+ days. I'm just hoping we don't have a repeat of 2011 during my build process. Or, indeed, ever.

Thanks, all!

[aggie79]

Looks like a fun project. On my build I used MDO - medium density overlay - which is plywood with bonded skins on one or in my case on both sides. MDO is commonly used for signs. I used it because it is a true 3/4" thick and it is available in 4' x 10' sheets.

MDF sounds the same but is medium density fiberboard. Instead of being made from veneers as plywood it is made from bonded wood fiber.

Look up Cap'n Telescope on this board. He lives in the Austin area.

Take care,
Tom

[Gage]

F/S templetes are always good to have. You can do all your shelf locations and mods on the temp just to see if that's the way you want it.

[Gunguy05]

I'm a huge fan of building a template first.

Now, I'm one that builds with sandwiched walls, and perhaps those that build walls out of a single thickness of plywood don't have much use for them. When building sandwiched walls –using plywood for the internals– I use the template to create 2 interior plys, 2 exterior plys, 2 plywood "internals", and 2 aluminum skins. Well worth scarfing two sheets of 1/4" ply together and using it to lay out your door location, bulkhead locations, spar ledge and a few other locations that I can't think of right now.

Here's the wife working on the "internal" plywood for a shandwiched wall. I'm fairly certain she's cutting two out at a time. The pattern is leaning on the house.



You can see where the fore and aft bulkhead mortises have been routed into the internal –and of course the pattern was used as a router template. (Those holes were used to clamp the plywood together to stretch it to 10' BTW.)

Cons? Takes another four hours and runs up $44 for your build. But throw the four hours out because if your making sandwiched walls (and skinning) it'll save you lots of time.

T

I will add to what Tony said. If you do make a template, make it out of at least 1/4, not 3/16 or 1/8. We use flooring underlayment which is 3/16 and it was a bugger to hit with a bottom bearing router bit. I know a 1/16 doesn't sound like a lot, but when you have the chance of slipping off and messing up your entire workpiece, it's a mile!

We used ours to layout the cabinets, the switches in the walls, the doors, as well as numerous other things that require a measurement to a curve from a reference point. Not to mention making lengthwise running ribs for use in the roof in certain areas, where they had to match the curve of the roof in that area.

[noseoil]

I agree about the use of a template. If you're replicating parts (the two sides, hatch ribs, etc.) it's really much easier and faster. The router with a 1/2" ball bearing bit is the fastest way to go. I do a rough-cut first with a saber saw (to get close to the lines), then do a clean-up pass with the router for a finished cut & a perfect match of parts. Making a pattern lets you work out issues full scale, which might be missed another way or on a small drawing.

The pattern is where you need to take your time. I used a speed-bore type of drill bit for all the inside corners (a hole saw would be just as good), a circular saw with a straight-edge for the long cuts, and a jig saw for the small stuff. Sanded enough to get a smooth pattern, then the router is used for the actual parts you make.

Here's the first side ready to go, then it's used as a pattern for the second side.


Hatch ribs are made the same way. Best way I know to match parts.


Side in place on the frame to check locations.