mikenlapaz

I'm new to kit building would like to get an idea of just how level building boards should be. I do not want to invest the time and materials and have an inherent problem of using an unsuitable surface.

I opted to purchase a building board http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXVZ63 and it arrived and was bowed both in width and length when it was removed from sealed package. One glue joint was open about .020" on the end (one side only) and extends 1.4". The maximum bow measured diagonally was .155"
Products Comments section advised it would take time acclimate to new locale.
It has been air drying for 9 days and the warpage / bows have improved. End A now .055" and End B now .070" Glue joint still open. Side to side bowing is still visible under 1/8" thick metal straight edge over most of the board.

Would you call it good enough or contact Tower and let them decide or adjust.

carrellh

I pulled mine out of the closet several weeks ago. It had some bow when I put my straight edgedown the length, and more when I put it across. I supported the edges with 1/4 inch square sticks, with the high side up, and put weights on it to flatten it out. I left it for a few days, removed the weights, and checked again. It took between 2 and 3 weeks but it is now pretty flat. I can see a little light under the straight edge but I am calling it "good enough."

You might try something similar. You will have to bow it past flat so it will be flat when you release the pressure.

mikenlapaz

Good ideas. Is your board put together with interlocking/finger joints or is it like sawn planks butt jointed together?

carrellh

I'll have to look at it tonight. I've had it for several years and never noticed.

Adibac

Straight building surface is a must... I use a 3/4 in. glass plane completely level.. It makes for very straight planes

mikenlapaz

What dimensions? How do you secure the parts? Magnets?

A pool table would be nice but .............

Adibac

2100 mm. X 11oo mm. I have a 22 gauge sheet of steel pasted on top of a little more than half of the glass plane, support the parts with magnets bought from e-bay. On the other part of the glass I set a self healing cutting mat.... Trabaja de maravilla....

Saludos

snurckle

I'm planning on building a table, plywood, in a horseshoe shape. The horseshoes/ends will fold down, and I'm gonna put some builders foam down on it for t-pins. Now sure where to get glass for it, and plexi has it's disadvantages when it comes to epoxy and CV.

iron eagel

With the glue joint open I would return it and have them send a replacement!
The glue joint open and it being warped is not something that I would accept.
Your building surface should be as flat and true as possible, any compromise will show up in your build.
I would also strongly recommend against using foam as a building surface it is not stable enough, homasote on a hollow core door is a good alternative.

krayzc-RCU

My Feedback: (31)

what is that ?

edsland

I use a 5/8 wall board over a table I made out of plywood so the pins will stick into the wallboard. But the flatter the better so your fusalage and wings come out straight.

mikenlapaz

I need to deal with this balsa board. Construction locally is block and concrete and plaster. I would have used considered another option but they were not available locally. Will try to get some pictures to tell the story a little better.

carrellh

My GP board is finger jointed boards making the length. The boards just appear to be edge glued to make the width, then planed smooth.

Any surface will bow without good support. The 3/4 inch glass that was mentioned will flex and sag in the middle if it is not supported. Hollow core doors may start out flat and true but they do not stay that way. Even solid wood doors will not stay flat and true forever.

Get the surface as flat and true as you can, but do not drive yourself insane over it.

WacoNut

My building table is approx 10 years old now and still nice and flat,
You may think this is overkill and maybe it is but here you go. I built a frame for the table 3'x8' the perimeter of the frame is 2"x6" with 2"x4" joist 12" on center. The table top is 3/4" finish grade ply and the legs are 4"x4" with 3/8" lag screws in the bottom for leveling. All the joints in the table were screwed and glued. I can move the table anywhere in my shop and re-level it in just a few minutes and it stays flat. I also have a piece of tempered glass that I put on the table top to build on. This may seem a bit extreme but if you want a straight airplane you must start with a straight building table. I have maybe $100 invested in the table and it has been worth every penny.
Anthony

mikenlapaz

This is after climatizing for 9 days. It is presently sitting inverted on (8) 3/4" square blocks with some sandbag weights in center.

John Sohm

My Feedback: (9)

Do yourself a favor and get a solid lauan door and put either a piece of homosote or a piece of sheetrock (gypsum board, drywall, whatever you decide to call it) on the door and you won't be sorry. You can even use a hollow lauan door (it's actually not completely hollow, there's cardboard corrugations inside it to provide additional strength and stability). I've been using one for years and it's still perfect. And they're relatively cheap, I think I paid something like $26 at one of the major home centers and you can get the sheetrock for like $8 and some change. Homosote is a bit more per sheet but it takes pins much better. Glass is nice and flat too but way more expensive and way heavier too and you need a bunch of special items since you can't use pins. And don't use anything other than tempered glass either or you really risk getting hurt.

So in summation, buy a door... it's definitely worth the expense.

mgnostic

I built my first RC plane (an Eagle 63) on a piece of ceiling tile laying on a carpeted floor in a mobile home. Probably not very straight but it shows that if you are careful you don't need to get too fancy. I've been using the same hollow core door for 15 years. If you can find one with a blemish they are really cheap. Mine sits on milk crates in my basement and is still building straight airplanes. Hollow core dores ar light enough that they can be moved easily and yet provide a big enough surface to build a quarter scale biplane.

dant-RCU

My Feedback: (3)

Your building surface needs to be flatter than a one-sided pancake.

Flat is good!!

Dan

CrateCruncher

My Feedback: (1)

Mike,
Your building board is trying to acclimate to the change in humidity between Illinois and southern Baja. You can try weights (cinder blocks etc) but make sure it has equal time on all sides exposed to the air before the warp becomes permanent! As is, it is unsuitable to build on. The photo you took should be sufficient to get you money back. Tower will most likely allow you to keep the board too!

Adui

Mine is gonna be my reloading bench. Build from slavaged cabinets and a counter top that was cut wrong so I got to keep it. Other than the rolled lip she's FLAT!!

mikenlapaz

I'm trying to give the maker/vendor a fair try as to time to adjust with just air on all surfaces. The thought of wetting one side has occurred, just using light weights at present.

I'm aware of the various alternatives. Any of you with this type/make of board, I would appreciate your experiences/comments.

mikenlapaz

I used weights on this board to get it measuring level and it stayed stable for a day, so I started building on it. The board was in-use for about 6 weeks. Well when I finished the wing and removed the plans was I surprized! I took these pictures to show just how much movement/distortion sitting with plans and protective plastic covering.

My thought is the butt joints versus the finger joints pictured and advertised. The split in the end, shows and is discolored was CA when the board was flat after the weight period mentioned above.

I have given it a fair try to make it work and now I will share my concern and disappointment with vendor.

FrankRC1

My Feedback: (5)

I use a 4ft by 3 ft tempered glass to build on. I lay the glass on my work bench slide the plans under the glass. I use small drops of thin CA to hold the balsa wood in place over the plans. When completed I go around and lightly tap wing half or fuse loose. I saw this on a Dave Platt build video. He uses a 2 inch glass table to build on but I could not afford a table like that. my glass is 1/2 inch thick cost about 90.00. The last plane I built was a T/F P39 everything lined up great. The plane flies great.

SPLIT S

I use 3/4" 13 ply Baltic birch or Apple Ply to build telescopes. ( The bases - alt/azimuth Dobosonian mount for some maybe Astronomy types out there as well ) It is VERY stable, it has to be, optics cannot be allowed to shift in alignment even the slightest bit. Two layers of something like that mounted on a solid level bench makes an excellent FLAT building surface. Unsealed solid wood is forever going to be trying to acclimate itself, the board as it is shown above can't be used except for the smallest of projects. If building is in your blood definetly take the time to make yourself a nice building surface. Building bows into the plane could present you with a plane that can't be trimmed at all. FLAT, FLAT, FLAT !!!

CrateCruncher

My Feedback: (1)

Mike,
Just buy a local door and a sheet of drywall or acoustic ceiling tile. (I know for a fact people use doors in La Paz!). Take a straightedge with you so you can verify its straight before you buy it. Try to find one you know has been in Baja for a while so you know it won't shrink up on you later.