jester125

I dont have my Sig LT-40 kit yet but Im making room in the garage to build it. I plan on using my 48"X24" work bench top with a piece of 3/4" plywood over it for a build surface. Will this be ok or do I need somthing else? Also what is the coldest temperature you can work with the glues and such? Im thinking my garage might be to cold, its gets down to 35-40 degrees.

thanks, Chris

Crashem

What you need is a flat level surface largest enough to build the largest sections of the model on.

as far as temp goes above freezing is important. Just remember that some glues and paints take longer to cure/dry in colder temps
If you have a small KeroSun space heater try using that when your building. I do that in my unfinished basement workshop all the time with no problems

CAPtain232

My Feedback: (40)

Jester,

THE most important tool in building model airplanes is a good FLAT (no bow or twist) building surface.....This is followed closely by squares and measure tools.

CRFlyer

I agree that being flat is the most important quality for a building board.

I do all of my building in my garage. I realize that living in Iowa that the temps are somewhat mild here, (I was from Minnesota originally) but my garage probably is generaly around 50 degrees during the winter months. I have had no problem building out there except that the glues behave differently. My CA seems to cure a little more slowly than it does in warmer temps, and if I need to use epoxy, I either wait until warmer weather or "sneak" the pieces into the house and do the gluing in there.

scott7x71

I use a solid-core door as a building surface. You can get one fairly cheap at your hardware store. Be sure to get one that doesn't have the frame and knob holes. You can lay it across most any table without it bowing or twisting and will have a long, usuable life.

Use a space heater to warm the garage a little so your CA's won't take too long to cure or you can use some insta-cure. I would use the heater first- the cure accelerators can make the CA bubble up and give you even more sanding to do.

Al Stein

About the building board... true, you have no better friend than a good flat board (or at least very few better friends). I build airplanes -- sometimes I build a LOT of airplanes, and I do check my board before each layup to be sure it's straight. Not only that, I also use jigs to ensure that things are laid up straight, and I even correct or redraw plans to fix the common unstraightness in those.

HOWEVER, remember that the real goal -- what you really want -- is a straight PLANE (not a straight board). And the particular plane you picked is going to be straight enough with or without the perfect board. The LT-40 has a self-aligning build-it-in-your-hands type interlocking plywood fuselage that really doesn't need a flat board. (If it's built in your hands, how would it know if your board is flat or not?) And it has a built-up wing from which twists can be removed (or added) when the covering is put on. (So a twist in the board won't hurt your wings, either.) That leaves curved wings as the only remaining danger of an unflat board -- but if they're both curved the same amount, then the curvature just becomes part of the overall dihedral and it doesn't hurt you either.

In my early days as a bread-winner, I worked for a master craftsman who told me that the thing that makes a master is not the ability to never make a mistake -- it's the ability to never have a mistake show. In aiplanes, it's not having perfect tools and fixtures or never slipping with the knife -- it's knowing what can be effected by an imperfect tool, fixture, or building step, knowing which effects are bad and which don't really matter, and knowing how to fix the bad ones.

3/4 ply is great stuff and you should be able to easily flatten it by laying a straight straight-edge across it (lengthwise, widthwise, and diagonally), putting some shims under low areas, nad fastening it down. And that is worth doing. But don't get too wrapped up in it... you'll need flatness later, but your present plane is not in jeopardy. For the LT-40 in particular, the effects of an imperfect building board are not bad ones. That plane will build up OK and it will fly well even if your building surface is not the best.

Just don't let worries about the building surface spoil your building experience. Building can be every bit as enjoyable as any other part of the modeling experience, so do what you can and enjoy yourself in the process!

(OK, fellas, I've got my nomex suit on... fire away)

FLYBOY

My Feedback: (11)

Sounds like your building board will be fine, as long as it is not warped. What I like to do is go buy posterboard from walmart and put it on the surface of the building board, use 3/4 inch tape between the sheets. If you spill glue and mess one up building a plane, you can replace it before starting the next and have a nice new clean work space.

Azcat59

Good stuff from Al Stein above. I don't know how many different building boards I have used over the years, but I stumbled onto the one I use most of the time now. Get a 4x8 sheet of plywood, preferably 3/4" thick, and cut about 2' off one end of the sheet. It will look like the grain on the outer layers is running cross-ways, and our minds think that is a bad idea. But somehow, that board is far more stable than any other I have had.

You could contact cement ceiling tiles or other soft surface onto it for ease of pushing in pins, but I just use as is. I cut the "T" heads off a couple dozen of the largest "T" pins, which allows me to hammer them into the board slightly without bending. I then pin directly to the board. For smaller airplanes a Celotex sheet or other soft surface would probably be better.

Next to food, water, and oxygen, a flat building board is pretty essential to the serious modeler!

Clair

jester125

Thanks all for the great info. I just got the kit in this afternoon when I came home from work. I took out the instruction book and it says "The building board you'll see us using in the photos is an 18" x 48" piece of 3/4" thick plywood (perfectly flat)." So I think I'll do ok with what I've got. Im trying to talk the wife into letting me bring my bench into the basement, we'll see how that goes.

thanks again for the great info, Chris

kdheath

Chris, it's well worth picking up a 4' straight edge at the Home-ly Depot and checking the building board corner to corner for flat. Won't take a whole lot of time, but eliminates one more big variable.

The best building surface I ever used was a piece of 3/4 inch tempered glass about 2 X 5 feet. FLAT! I know a guy who builds on a 6 foot long granite slab from a monument company. One other hint is to pick up an old steel desk at an auction or sale and use it for a building table base. Won't ever warp from temp/humidity changes. Solid core door on top of the desk. BTW, the home stores sell damaged doors for pretty cheap. I think I gave $12 for one with a small ding on one corner.

One place that a really flat surface pays off is in trammeling the airframe during final assembly. If your surface is flat, you can measure up easily to check incidence, and be sure the wing and tail are on straight, etc. What's really nice if you have the room, is to make the work surface an island-out in the middle of the room, so you can work around it. Better to walk around the work than move the work all the time.

Just a few ideas I've run across over the years.

Kelvin

Al Stein

That metal yardstick will come in handy in ways you never forsee... one of my very frequently used tools and it costs no more than a few dollars.

My board a door but it's covered with ceiling tile, too, It works very well ad is dirt cheap. I like Homasote board a little better (comes from lumber places as a sub layer for under flooring), but not enough better to spend the money. I also have a balsa board for things that fit on it. There's no way I know of to get more bang for the buck than the ceiling timle fro a pinning surface.

I also have a piece of a vinyl house siding panel on my building bench. It's a great surface for cutting anything that you use a knife for. It has no grain, so it doesn't drag the knife blade away from where you want it, it doesn't wear your knife blades, so they last way longer and give cleaner cuts, it's sorta self-healing giving fresh new surface if you scrape any cut lines with a blade held vertically once in a while, and it's free if you get it from the house remodelling up the street -- and very cheap if you get it from the lumber store. (I don't know why they made that pretty little blue house grey, but their old blue siding has served me well since it stopped serveing them.)

cde0214

First of all, congrats on the LT-40 I just started flying a few months ago and that is the kit I chose. I soloed in nine days and I give credit to the plane and the instructor. When I built mine I started with a good flat surface, and then I found a cork message bord that was large enough to hold the wing, this allowed me to pin the wood in place over the plans. Very handy!! The plane went together fine and after sixty-one flights I'm proud to say, its still in one piece. Don't take this the wrong way, I'm not bragging on my piloting skills I just you to know that you have picked out an excellent trainer.

Cowboy1

O.K. I've gotta compliment you on your choice of planes to start with. I went with the same plane 9 months ago when I started, and I loved it. I have a question of my own that would fit in well here. I'm on my 3rd plane, a GP Giles-202, and I was thinking about shelling out the money to buy a Great Planes magnetic building board. I was wondering if any of you have any recommendations on this purchase. I think this will be an easier way to secure the parts to the building board, but I don't want to spend money on something that I don't really need. Just for the record, I built my LT-40 on a board consisting of 3/4 inch plywood with 1/2 inch pink foam insulation taped over it to stick the pins into. It worked fine for the trainer, but I'm a little concerned that a higher performance airplane needs to be a little more precise.

Al Stein

I've known a few guy who had the magnetic building board and they all loved it.

I've heard two other comments on it -- one was that it's easily transformed from a good tool to a great one by adding more magnets and accessories (generic sandwiched-between-steel-plates magnets from your local internet magnet store working perfectly), and the second comment that the board itself could be replaced with a stiffer (thicker) piece of stell sheet from metals suppliers almost anywhere.

Personally, I use a similar system that's gravity powered: I have several compact but massive blocks of steel that I are machined to precise square corners and flat faces. The steel blocks came from machine shop block scrap (available at machine shops everywhere for no more than almost nothing... often for absolutely nothing). It's just another inexpensive option. I personally prefer the gravity system for this reason (warning: the part most people would want to read has already ended)...

Both the magnetic and gravity-based fixturing systems hold their positions based on attraction forces that get stronger as you get the jigging parts closer to the body that they share the attraction with.

For the magnet, that attracting body is the work surface and the jigging parts are positioned no more than a couple thousandths of an inch from it. So when you adjust the position of a a jigging part, a small dislodging motion will move it thousands of times as far as it was in its original position. That means that the holding force drops almost instantly from several pounds to almost nothing. It's hard to move the jigging smootly into a corrected postion when that's happening.

In the gravity system, the attracting body is (for practical purposes) the center of the Earth, 2000 miles away. Reposiotioning the gravitationally attracted steel blocks, even by lifting them several inches off the board, has makes only an immeasurably small change in it's thousands-of-miles distqance from its center of attration, so it makes no measurable change in the amount of force and friction that hold it in place. Therefore, it can be moved smoothly by applying a STEADY force... it's hold on its position won't suddenly dissapear, it'll just remain steady so you can move it as much or as little as desired with a steady force against it.

Is the difference critical? Heck, no! Is it noticeable? Yep, it is. Is it easy to achieve? Sorta -- but you have to go as far out of your way as a machine shop. Anyway, both are good systems and you can tell my preference... yours is up to you.

Cowboy1

Thanks for the advice! What you say makes a lot of sense. I think that I will try to incorporate both systems into one. I will start by shopping for a higher quality (ie: thicker) plate for use as the board, and see about using both magnetic jigs and the gravity powered models to hold everything in place. I know I've never used either one, but it makes sense to me that there will be certain instances when one or the other is the best choice to use. The best thing is they both use the same basic board, so it's a win/win situation!!

hookedonrc

It has been mentioned, but thought you might like price ideas. I went to Lowes, asked the guy at the counter if he had any damaged doors that I could buy. I went with a bi-fold hollow core door that had two doors about 18"X72" the only thing missing was the hardware for installing: Cost $16.00 for both doors; 2 ceiling tiles $6.00; 3M spray on adhesive about $7.00 Total: $29.00, and I still have one of the doors left.

Instructions.
I spent the time to shorten the door because my work area was smaller than the length of the door. (Probably not needed for most,)
I took the door, using the best one and best side with no warping. Sprayed on 3M adhesive to the door, and the decorated side of the ceiling tile. Let dry. After it was dried, I took a drywall saw and cut off the edges to match the door exactly, ran my hand along the cut to smooth it out. Walla...building board! You can take it one step further if you like. I put a handle on the end of the door, and a hook on my garage wall and hang it up when it is not in use.

Jimmbbo

As mentioned in earlier posts, flat is critical. For me, so is "cheap" and "portable"

For over 15 years, I have used 12" x 5/8" luan veneered particle board shelving (cheap) with 3/8 inch thick fine grained bulletin board cork on the building side. They are still dead flat after years of alternate use and storage.

I made three boards - one is 6ft long for assembling wings or fuselage, plus one 24" long for horiz stabs and elevators, and one 12" long for vert fins and rudders... They are easy to store when not needed, take up very little table space while in use, and allow one part of the project to be set aside to dry/set while working on another.

The only downside is that the plans have to be copied or cut apart and placed on the proper board...

HTH

Jim

CAPtain232

My Feedback: (40)

Here is a couple of pics of my table...First pic show the table with squares magnets and straight edge...I have over 50 magnets in a variety of size now. Second pic shows just one of many shims to create a PERFECTLY FLAT SURFACE. Third picture shows a leveling foot. The magnets and squares are used to create and ADJUSTABLE JIG

CAPtain232

My Feedback: (40)

A few more pics. These will show how I use the magnets to hold squares in place....You will also see how the magnets hold PARTS in place

Cowboy1

CAPtain232, a couple of questions. First, what you have is pretty much what I had envisioned as my IDEAL table. I just don't have a metal shop where I can fabricate something like that. I was wondering if you did the work yourself, or had it done by a shop. Then there is the age old question of how much did you spend on it? I'm also interested in where you got your magnets. I like how you have the square stock bolted to the magnet to hold things down. I know you probably just went to a home store and picked them up, but heh! you gotta learn somehow!!! O.K. I may have to shoot you an e-mail to get some specifics on your table. I just thought some others might be interested as well. I would really like to know how to replicate what you have, but I know that would probably take up a lot of space. Thanks for the ideas!!!

CAPtain232

My Feedback: (40)

Made it myself.....I used to work in a welding shop and have played around with welding since I was a youngster....The magnets you can find in some TOOL SALES....if you go to a TOOL EXPO, there is usually someone there selling the inexpensive stuff...I got a few from MENARD's, but they were $4 to $5 each.....tool show special $1 each...I have several different sizes. Some of the magnets have so much pull that I have to PRY them up.

The table is 2ft x 8ft and stands about 32 inches high...with adjustable feet The framework is all 2x2 Square tubing 1/8 wall. The top plate is 1/4" thick.

I also built a WING PRESS. It is 2x2 tubing, but 1/4 wall with 1/4 plates......I spent about $700 building both pieces...The table was probably $225 to $250 and the press about $450 because it is all heavy tubing

OldRookie

My Feedback: (13)

Here is my building board cost:
2 X 4 Lumber $20.00
Angle Iron 3.00
Hollow Door 20.00
3' X 6' 3/8" glass 60.00
3' X 6' 16 ga steel plate 37.00
3/8" SheetRock 4.00

With the bolts and everything it is about $150.00. Worth every cent.
The hollow core door had a nick in it.
The 3/8" plate glass was salvaged glass. You can get it at some glass shops.

Greg