[Triumph1974]

Has anyone that has put in the tapered pin as described at the following link http://wiki.matronics.com/wiki/index.php/Nose_Gear_Strut had any trouble with the standard HSS #3 reamer from Spruce not actually making shavings when reaming out the hole? It seems that the reamer I got PN 12-09900 only rotates around the hole without making shavings. It is make a few shavings for 2-3 rotations, but not much. Perhaps I need a reamer made out of stronger steal than standard HSS.

Has anyone else had this issue and if so, what was your resolution to the problem?

Thanks,
Paul

 

[mdoyle]

You might want to search the archives on this, there are many posts on the topic. This was difficult for me to do by hand, and I ended up having to use a slow turning, high torque 1/2" drill to complete the job. The nose gear strut, (at least mine) was very hard and it required lots of pressure and cutting oil to keep the reamer cutting.

 

[rzbill]

I did it....BUT

I taper pinned all 3 legs.

The reams don't work. Broke 2. I'm no neophyte with machining. Had to get legs wire EDMed and match ream the weldments. Legs must be harder than when matronics plan came to be. **EDIT - No Hardness change. See comment from Richard below.**

Unless you are ready to do it this way, DON'T START. It is a one way trip

 

[David_Nelson]

Sounds familiar...

Hi Paul,

Things started out "ok" and then it seemed I ran into something a little tougher than the reamer could handle. I went down the path of using a 1/2" "heavy duty" drill w/ 2:1 reduction and cutting fluids and that didn't help either.

I ended up ordering a #3 B&S Helical Taper Reamer from the Gammons Hoaglund Company for ~$60 back in Nov 2008.

http://www.gammons-catalog.com/store/pc/viewPrd.asp?idcategory=25&idproduct=475

I eventually managed to get things jigged into a drill press and even then it took quite a bit of pressure for the taper to cut. Point being, I did eventually get it done but it took a lot of effort and time.

Good luck,

 

[Triumph1974]

Thanks guys for the insight....well I am already committed to this route. I "stepped" drilled the hole out in 3 different sizes, so the reamer doesn't have to cut that much out and have about 3-4 threads of the taper pin coming out of the back side of my tapered hole....so I think I am somewhat "close" as I have a very nice taper pin hole, but it is just not quite large enought right now.

I may try and get a carbide reamer from the folks at gammon and give that a try. Will let you all know the outcome.

Paul

 

[sandifer]

Taper reamers are designed to be used by hand. Use a good two bar tap wrench and do it by hand. Do not use a drill. I used a Brown and Sharpe taper on my RV-3 gear legs and trashed one reamer by not applying enough pressure initially. If you don't start it cutting right away, you'll dull the reamer very quickly and it will never cut well. Could be the problem you're encountering. I tried again with a new reamer and it worked perfectly. If you apply a good bit of pressure, use a good cutting oil, you should be making consistent shavings and cut the tapered hole fairly quickly. After drilling the holes, reaming was the easy part.

 

[rzbill]

I do want to be clear.

I was typing from crackberry on previous post so it was short.

I do want to describe my ordeal for everyone.

Started by hand. It went in a little, maybe 1/3 of the hole depth but never peeled a "chip". The cuttings were always small flecks like grinder dust suspended in oil. Worked up a real sweat getting to that point and knew I could never complete the hole that way. I was leaning on the ream with all my weight and turning it with a 18" cheater and using various cutting oils settling on sulpherized oil.

I tried a slow speed drill motor for a minute or two but that went nowhere and nearly ruined my drill motor.

I step drilled to relieve some load. The drill shavings were very indicative of brittle failure of hardened steel. Pretty much trashed the HSS drill bits I used.

SO, I jigged all this into my milling machine so I could use the quill to apply pressure. I worked the hole for a couple of hrs of cheater bar sweat and less that 1/32 progress before snapping the ream in half and NEVER curling a chip. All I got was dust.

So. Everybody says I dulled the ream. I ordered a new one and snapped it in about 5 minutes. Same non-curl chip. I tested the broken shard on 28Rc 4130 and it cut like butter, almost with fingers.

So.. Go ahead and try it. I was not lucky enough to find a carbide helical ream when I was in the throws of this work. I gave up and EDMed the holes. They came out great, but the whole ordeal cost me over $500 before it was over. This included 3 reams from ACS plus the pin hardware, 3 EDM jobs and the time and effort to make an EDM jig for the main gear legs to get the pins in the right orientation because the first hole I partially reamed was a battle zone and create drawings for the EDM guy to CAREFULLY follow.

I still say this is not for the faint of heart. I came VERY close to pitching the legs and ordering them new from Van again.

If the legs were 10 or so points softer in the Rc scale, the job would have probably gone without a hitch. I contend that the legs have a higher heat treat now than they did years ago. It helps with ultimate tensile strength and may have been revised over the years. Mine are roughly 2008 vintage.

**EDIT - See e-mail from supplier Richard@Langair below. Leg hardness has not changed. In that case, I tip my hat to the gents that have sucessfully taper reamed these legs with standard tooling.**

 

[Richard@Langair]

This is definitely not something you want to mess up as rzbill suggested.

If you don't use a good sharp ream made from HSS or even Cobalt, then you will have trouble and work harden the steel on the surface of the hole. Once it gets work hardened, good luck. We have scrapped a couple legs when tools have gone bad and work hardened the hole. We even could not save the hole using Carbide in a good rigid machine.

If you are not getting nice curled chips from the start, you are already too late.

It takes a nice slow turning tool (100-200 RPM)
with lots of pressure and lots of high quality cutting oil. We use Mobilmet Omega when drilling this material.

The legs have been the same hardness since Whittman first came up with the design. There are only a few times the legs have varied and those have not been Van's designs. Other manufacturers.

Hopefully this helps.

 

[Triumph1974]

Finished the Taper Pin

Hello Everyone,

Just wanted to let everyone know that after several weeks (working a night or two per week and a few hrs. on Sats) that I have finished reaming the hole for the taper pin! I probably spent 6-7 hrs. working on it by the time all is said and done.

Thanks David for the info on the Gammons taper pin.....I ordered a coated reamer from them ($80 now) and with a lot of elbow grease, and a little cutting oil I was able to finish the hole......the gear leg doesn't rotate at all with just allowing the pin to drop in the hole.

For those thinking about doing the taper pin.....after you "step drill" though 3 different sized drills in the hole be prepared to do a lot of "Grunting" as you have to put a lot of pressure on the hand reamer to get chips out of the 6150 gear leg steel.....it would probably help if you got a few guys to help out that are BIG.....and make sure you use leather gloves when reaming to avoid getting blisters on your hands.

I did end up using a dremmel tool and stone to lightly clean up the work hardend steel a few times while hand reaming...but of course you don't want to do this to much or go very deep.

Thanks for all the comments,
Paul