aparchment

aparchment

Well Known Member
Okay guys, I spent about half an hour on edge finishing the VS rear spar doubler this evening and on the HS it took me about an hour to edge finish and polish the surfaces. I am taking to heart the Van's instructions that I remove all saw marks and evidence of cutting. Am I going overboard? I just don't want to spend all of this time building a plane only to have to deal with crack after crack. Suggestions?

Antony
(newbie 7A builder)
 
*Disclaimer:

This is purely my observations from my three years as an A&P, I have no experience with building and not much maintaining RV's.

From what I have seen as far as aluminum cracking, you'll need a combination of a stress riser AND strain on the piece. To elimnate stress risers, debur and polish the edges. But don't go overboard, polishing is one thing, but removing ALL tooling scratches might be a bit overboard. To eliminate stress, make sure all your holes are lined up before you rivet. You'll always have some parts that won't be perfect, but do the best you can. Also don't try to build your tolerences too close. They are called tolerences for a reason :). I have not seen much skin cracking in my time as an A&P, spars and ribs are more critical, so be more careful deburring them, but again, sharp edges should be polished, but don't worry so much about removing so much as radiusing tool marks.

It's kind of hard to explain what I'm getting at without demonstrating in person... oh well, I tried.
 
Anthony, you don't tell us how you are going about cleaning up the edge, but a few minutes with a Scotchbrite wheel is all that is necessary. I generally make three passes: A slow pass normal to the edge, and then two more quick passes at 45 degrees to the edge to knock off the sharpness created by the first pass. Five minutes max to do a VS doubler, maybe a few more minutes on the deepest part of the V with a hand held die grinder and one inch Scotchbrite wheel, and that should do it. You will get faster. You don't want to remove too much material. Sometimes, Van gives you just enough and no extra. Steve
 
Make sure you have the right scotchbrite wheel - the ones from Avery (or equivalent) work best. Once I got the Avery 6" scotchbrite wheel this whole process was much easier.

Keep in mind that this (and the HS equivalent) are significant structural parts of those pieces; a little extra time spent here to get rid of all tool marks and scratches will make you feel better pulling g's later :D . There are not a lot of parts in the kit that require extensive polishing / deburring like this. I spent a little extra time getting these just right.

Thomas
 
On thick parts like doublers, you'll have a much easier time if you go over the edges with a file first, then the scotchbrite wheel. The wheels are great for removing fine marks, but will take waaaay too long if the marks are deep.

Steve Zicree
 
Yeah - forgot to mention that. Those doublers have some heavy marks from the stamping / machining.

I used a file and a combo disc/belt sander (bench tool) to smooth out the machining marks then scotchbrite wheel to finish them.

Thomas
 
Antony,

I use a combination of devices depending on the thickness and shape of the part needing finishing. The angle grinder with the scotchbrite cookie is TREMENDOUS for finishing off thick parts with deep gouges and/or saw cuts.

Next on the list is the 3M Cut and Polish wheel(s). They are just the ticket for skins and the 2" ones are AWESOME when chucked in the drill press for lightening holes on the ribs!

Other gee whiz tools are the el cheapo sand paper blocks loaded with some decent grade oxide sandpaper. I use that on the long, straight cuts and edges. The "V" notch tool is a good one. I usually use that prior to sanding those long edges.

Drum sanders from Home Depot and the smaller ones that fit into the Dremel are quite handy.

Finally, everything gets a finishing swipe with a sheet of maroon Scotchbrite.

Basically the part is "DONE" when the edge is smooth, you won't cut yourself and there are no jagged edges.

This is a custom, hand built plane. Take your time on it. Make it pretty. After all, your time is worthless. You are an ameteur.

...but they come out better than a spammer!

;) CJ
 
I used my vixen file for those larger bumps along the edges of the doublers followed by a pass or two on the 1" belt sander and finished all surfaces with the scotchbrite wheel (stack o'three) on the drill press.
Steve
 
edge finishing advice

Thanks guys.

It sounds like the procedure I have been using is pretty much the norm, and I guess I will get faster as time goes on.

Basically I hit thick edges (like the VS spar doubler) with the vixen file first, then a 2" fine sanding disk in the grinder for a couple of passes, then finally the fine grey scotchbrite pad.

On thin pieces, like the spars or ribs, I hit it with the vnotch tool first then finish up with the scotchbrite pad. The hard parts on these pieces are the notches at the corners. Those slow me down.

Antony
 
Edge Finishing

You don't need to get the edges this smooth.....I built the whole plane with....files, sandpaper, and scotchbrite pads (hand pad). Call it sadistic but I enjoyed drawfiling (12inch smoothcut and 6in smoothcut) the edges and then finifshing it off with 320 Aluminum Oxide sandpaper. Just put the brain in neutral and file away.....Toolmarks come out quite fast with a sharp file. It was a good way to unwind from the daily stressors..... :eek:
 
Drawfiling

Marc DeGirolamo said:
<I enjoyed drawfiling (12inch smoothcut and 6in smoothcut) the edges and then finifshing it off with 320 Aluminum Oxide sandpaper. :eek:
Click to expand...

Marc,
I occured to me that some folks might not know what drawfiling is. So I'll try to explain. Normally a file is used by pushing it on it's longitudinal axis. In drawfiling it is pulled (or pushed) sideways. This way the angled teeth act similar to a woodworking plane. The result is a very smooth finish. Of course the file needs to be a smooth cut file for a good finish. (mill smooth)

Mark
 
Last edited:
If you are looking for a cheap small file for edge work, go to Home Depot or Sears and look in the gardening section.

You need an Oregon chain saw tooth setting file, they are about $6 and may come with a depth gauge for a chain saw. They are Swiss made files, 6" long, safe edge both sides and cut superbly. I have never used a better file on aluminium or aluminum !!
 
The best thing I find for deburring the rib notches is the 1" wide emery paper that comes on a roll - it makes radiusing all those little curves a breeze.
 
You must log in or register to reply here.