Nose ribs and wood grain

[Peterross]

Hi all

Anyone have info on how the nose ribs should be oriented on the plywood?
I'm getting ready to rough cut them and want to know if there is a preferred method of laying them out on the wood"?

Thanks

Pete

[Tom XL-7]

Pete 
  That's a new question. Have not seen any info or comment on the subject. Mine will end up with the veneers you see running horizontal, as in from spar to the tip of the nose.
That will be a function of how the nose ribs layout on the plywood I purchased for the purpose, not some conscious structural reasoning. If I need a few extra and they layout on a waste piece in some other orientation, I will not think twice about it. 
 Hope that helps. I don't think it matters in this location. 
Buy quality plywood and it shouldn't be an issue.
Tom XL-7

[Peterross]

I thought I had seen a photo or drawing of a sheet of plywood at one point. I don't remember how it was laid out or where I saw it.
I did buy good plywood from Wicks. Just want to use as much as possible without waste, but want to make sure I don't ignore some grain orientation issues.

Thanks for the feedback.

Pete

[scottiniowa]

This is one of those areas, that can be contemplated (both ways-sorry) to the 9th degree.  And being "the boss" has not stepped in on this, I think it would be safe to say, this is a non-structural local.  i.e., the direction of the grain, won't help or hinder the strength of the wing, and is plenty in either direction for full support of the leading edge.

it is stunning, just how tight you can get all the parts laid out on a sheet, when direction is not the dictating entity. Very little scrap. For those of you new to this, it often works well, to cut your exact templates of each part first. Then lay these out on the sheet, with largest first...  Often by having two interlocking  () with a small part in the middle, you can really cut down on cost and scrap.   If you really get tight, the skill becomes working your jig or band saw between the lines to cut the raw parts. But can be done.

I have found that stacks of raw parts, with steel template (wood master works too) then router ed works extremely well as shown by a few on this forum. We generally did 4 at a time with the master.

Best of success.
Scott

[Peterross]

Thanks

Sounds like there is no issue with grain orientation.
I did create a template out of aluminum, and will use a skill saw to rough cut, then stack and route them to size.
It sure is nice to see progress.

Pete

[scottiniowa]

Sounds like there is no issue with grain orientation.
I did create a template out of aluminum, and will use a skill saw to rough cut, then stack and route them to size.

This will work great, but using a band saw to cut out rough pieces will gain you far more on a sheet, than hoping you can get them all with the skill saw.

[Tom XL-7]

I believe Scott is thinking circular saw while Pete is thinking scroll saw.
Skill is a brand. I am familiar with it representing both. 
Whatever you call the thing ( I use scroll - jig saw is common as well)  the hand held reciprocating saw with a base is a good way to attack a sheet of ply. I don't enjoy long flappy sheets or strips of ply on my limited band saw table.
Off topic horror story
One of my employs was to renovate a space where the Govt. would sell surplus. There was this beautiful walking beam jig saw with a 60" round table. It was from Wright -Patterson Air Base.
  The public could not buy.  But a church bought this machine. Yeah- right.
Well we helped the clown load it in his boulevard worthy pick up truck and both warned him it needed secured as well as offering rope and blocking.  it didn't go 3 feet without rolling thru the tailgate and cracking in half on the ground. the machine was repairable, I have seen many welded bases. And now I knew where they came from.
Tom XL-7

[scottiniowa]

I believe Scott is thinking circular saw while Pete is thinking scroll saw.
 
Tom XL-7

Ahh, yes, I was Tom, and good point.. I love progress in this area, as it greatly reduces cost of total parts.

Cheers-Scott

[ParQld]

.....Or you could laser cut them as i did here, if you know someone with a laser cutter.

https://goo.gl/photos/eKkes49J4rEJhoe18

cheers Paul

[scottiniowa]

.....Or you could laser cut them as i did here, if you know someone with a laser cutter.

https://goo.gl/photos/eKkes49J4rEJhoe18

cheers Paul

excellent Paul- Look great, and you could then cut ALL the parts..At least that would seem like a great thing to do.  So based on standard Laser cutting rates, what does it cost to do these parts?

[ParQld]

Scott ,

I had them done a while ago and the job cut about 66 ribs (i have spares) in about 86 minutes, they charged me about $250 AUD (current rate $180 USD back then it was a bit more) including setup for the privilege .

whats amazing is the yield. I think we did abut 66 Ribs out of a 4' X 4' sheet of ply and I have also used the off cuts (spru) for other hand cut parts. If you had everything set up correctly you could technically cut all the parts. The only issue that I mentioned in an earlier post is that you have to allow for sanding to get the burn marks off to ensure good glue adhesion.

I only did mine this way for Fun. it may not be for everyone.

Paul

[dz1sfb]

I gotta agree, laser is for me the way to go. I have suppliers who do my laser cutting for kit accessories out of aircraft ply and the finish and consistency is second to none. Now there can be a difference in the laser operators as well. Hence, I have one preferred supplier over another.

[joecnc2006]

I'm fixing to layout my ribs and other pieces nested in the ply and see how much material i will use, then cut them out on the CNC Machine, the difference on the laser and the cnc machine.

There are some differences I see from the  Laser verses CNC cut parts.
The CNC machine I will have to add some tabs for the parts to hold them in place once cut out, sometimes they can pop out and be caught by the Bit and a corner messed up or slung out of place and then laying where another piece may need to be cut. On the laser the parts mostly lay there in place when cut. Material sheet hold down will need to be considered, since I do not have a vacuum table i use double stick carpet tape to hold the material in place, i use it mostly on thinner material and it works pretty well. The Part cleanup on the cnc parts i think are easier than the Laser machine I just use a flush bit in the router table to cut the small tabs. from the three to 4 places in the parts it goes really fast. The laser machine you as "Paul" mentioned you will need to sand the edges, to remove the burn areas. which may take just a little longer and being sure not to sand to much to change part size.

I will post a screen shot of the parts nested when i get them done this weekend will be interesting to see how it looks.

[scottiniowa]

I had them done a while ago and the job cut about 66 ribs (i have spares) in about 86 minutes, they charged me about $250 AUD (current rate $180 USD back then it was a bit more) including setup for the privilege .

whats amazing is the yield. I think we did abut 66 Ribs out of a 4' X 4' sheet of ply and I have also used the off cuts (spru) for other hand cut parts. If you had everything set up correctly you could technically cut all the parts. The only issue that I mentioned in an earlier post is that you have to allow for sanding to get the burn marks off to ensure good glue adhesion.

Paul

Excellent Paul, one of the things I enjoy about folks sharing their experience in building, is the whole thing, in which case is the cost as well. As most know, I spend a great deal of time building aircraft for others, and there are simply some things that labor can not tackle effectively. (based on $10.00-20.00 hour) The wheels for example. Yes, I could build them, but at a cost of perhaps $80-90 each in labor simply does not make it OK. Not when I can buy them for 1/2 or less.

So in your case, you could easily be at the price, where when you toss in "everything" this  fee to have laser cut, is or could be a great deal for each piece.  This certainly the reason I made the supplemental plans available, as just the head scratching time savings, pays for them.   

So in short, well done.
Scott