Jig timber

G'day all,
It's been a bit quiet in the -4 forum,.,.so I thought I might ask a question,... I have just bought the Timber for my Jig, bought 3x pergola posts, ( 4x4) 10x10 in Aussieland, They are untreated pine, clean cut, and one of the has the slightest of warps in it. I was wondering if anyone else had problems with their timber. Also is there any need to support the center of the cross beam, to try and reduce any sag, or do you not think it will be a problem with the 4x4's ??
I am building the Jig this weekend so I am Looking forward to getting started!

JJ

Jig a Jig

Hi, are you talking wing or fuse jig? 4x4 posts for wing jig are fine, just keep your plumbobs hanging and look at them each time you walk in the shop. You will need to support the centre of the wing spar/rear spar until you have the skins on. I did this with a screw type jack.

The fuse jig should use seasoned timber so no warping occurs, but again, keep checking your centreline and plumbs before doing any work. It also helps if you build quick and have it in and out before the next ice age, unlike some of us early scratchbuilders.....

Keep at it!

Grant
RV-4 VH-PIO

empennage ?

I think he means empennage. Welcome aboard !!!

The cross beam can be supported by taking a (for example) 1/2" piece of plywood and glueing it to the bottom to form a T.

The beam doesn't actually have to be horizontal as long as your lines are straight for mounting the elevator hinge brackets. Avery sells these little black buttons with a hole drilled through them. You can insert them in your hinge brackets and just shim until they are all parallel.

As Grant said though, the sooner you're out of that jig, the better. In the meantime, check often.

Good luck.

John

Jigging

Well I have constructed the Empanage and wing jig,..all pieces had a some degree of warp in it,..but luckily enough in only one direction, so All I had to do was turn the timber for another edge and all was strait. The distances between the verticals were set at 116 inches, right inbetween the suggested 115-117 Inches,..we are just starting to warm up here in Newcastle, so things will be starting to happen soon,..I don't have easy access to an international fax,..so I will be waiting until this thursday to send of my order form to Vans,..coaxed a friend into faxing it from his work for me,... anyway I'll post pics tomorrow when I remember to bring my disc in!,..

Oh yeah I have been lucky enough to sit in VH-PIO a couple of times,..so Thanks to Grant ( Sir , to me,.. ),..I can't wait to start,..I have been told 3-5 days to my door,...

JJ

Pics as promised

Well as I promised here are the pics, The cross beam looks bowed, but it is dead level,.. ,...well it doesn't seem to be working,..ill try again in a bit,..

Wing Jig

I built mine of the straightest 2 by4s I could fine. I think they were fir. I selected them so that if there was a bow, I could fit two together with opposing bows. I bolted them together in about 4 places along their length. I used them for two wings and I never had a bow develop in the vertical or horizontal pieces. Sometimes you have to take a lemon and make lemonade.

Bob

Mate thats not a bad idea of the 2 2x4's,... might have to remember that for the fuse jig,.. ,..like you said,..I have turned lemons into lemonade,..I can't stop looking at it,..I know its the very beginning,..but for me it's been a while in the making, and I am so looking forward to it I can't wait to take delivery and have something bolted between the posts,..

JJ

here we go,...

For Free

Well due to a change in circumstances ( moving house ), the Jig is going for free to who ever would like to come and pick it up!,.It has never been worked on and I have all the bits needed to put it back together,.. Email me if you need any details

JJ