Member postings for Dave Smith 14

Ron

Buy one of CUP's EF starter packs, they are about £16, has flux and 2 x 1 mm dia and 2 x 1.5 mm dia 455 rods which will be fine for what you want to do. It also includes a hints and tips document. I bought one when I first started silver soldering.

Dave

John

Also worth asking the question on MECH, link below.

http://modeleng.proboards.com/

My WM16 has tight spots on the 'Z' vertical axis, probably due to similar issues to yours. These machines are very much built to a price. The difference in the quill axis position (checked with my DRO's) between the headstock locked and unlocked is about 0.25 mm in X and 0.15 mm in Y. Hence I always lock the headstock and use the quill feed as Jason says. I thought this was normal practise anyway. The few times I have run unlocked you can tell with the vibration. Also check the quill bearing shaft bearings, mine was just out of warrenty when the bearing retainer for the lower bearing worked loose and the shaft started wagging all over the place breaking the cutter.

Lock it all up and try the same cut again. If it is still bad then you need to go back to Warco.

Dave

Dave, a lot later than you think. I volunteer on the Mid Hants at Ropley. The 'BR' not Southern drawings done at Ashford in the 50's for Spam Can tenders are all in fractional inches, with a few odd dimensions mainly diameters in decimal. As an aside in 40 years of professional engineering, these drawings are some of the worst I have ever come across.

Dave

They do not need to crash test, just put each car through an IVA test same as Caterham, Westfield etc do for cars they build ready to run for customers. Anyone who builds a kit car has to do the same.

Dave

Max mass you will see with loco, structure probably no more than 250kg tops. So well within the loading capability. With regards to bending due to offset loading, it will probably be ok, but well worth a punt at that price.

Dave

Ron

Very nice job you are doing there. I have absolutely no problems with laser cutting parts, life is to short to spend hacksawing and filing. I am building a Don Young Aspinall class 27. My retirement present to myself from work was any thing that could be laser cut was. I ended up with over 300 parts!

Dave

Paint 3D can draw primitives (cubes, cylinders etc) but you have Boolean addition, subtraction etc, eg you cannot add a cylinder to a cube. Basically useless for any engineering type function in my opinion. Continue with your existing CAD software and just direct the stl file.

Dave

Barrie.

Rather than try use a procedure critical process in home environment, have you considered changing the grade of Aluminium or changing features in the design to reduce any stress concentrations. Indeed has the component actually been stressed? If you are using say 6082-T6 you could change to 2024-T or T6. In this cases you get the double whammy of higher stress limits at yield and puts you further to right on the fatigue curves. Mil HNDBK 5 has the all the data you need and can be downloaded from the interweb.

Dave

John

I am already doing the job for Bill, in fact it is finished I just need to send the dxf and pdf for Bill to check he is happy with it.

Dave

Bill

Email me your drawing and I will produce you the dxf file which Malcomn needs. I will message you my email address.

Regards

Dave

Tim

Mostly agree with you. MSA ratified circuit race costs will be around £400/500 average meeting costs (entry fee, fuel cost for race and tow car, bits and bobs etc) over a season assuming no major mishaps and excluding the cost of car, helmet overalls etc. For sprint/hillclimb this will reduce to around the £250/350 mark. For track days normally only a 'suitable' crash helmet is needed, while the only car special safety equipment may be a fire extinquisher.

Dave

Dave

Well done you have explained the method of simple solid modelling very well (I had about 20/30k hours seat time on CATIA V5 during my working life and still probably do about 500 hours a year in retirement). Although the actual commands will differ the majority of solid modellers from FreeCad, through Fusion 360 to SolidWorks and CATIA all work in essentially the same way. I totally agree with your differentiating between 2D CAD drafting and 3D CAD modelling. It is essential for newcomers to understand what you are creating is a virtual part with, volume, mass etc. I particularly hope Nigel Graham2 reads this and has a go following the guide lines you have described. It is not rocket science using 3D modellers, in fact at work we taught people who had no engineering experience what so ever how to do quite complex models and to blow down 2D drawings.

Regards

Dave

Ron

On the various grills have you considered getting them either laser cut or etched in either steel or nickel silver. They could be made from two laminated layers one with the grill vents the second and overlay to form the surround.

Dave

Harry

Can I suggest you direct your enquires to RMweb

https://www.rmweb.co.uk/community/

That site is much more suited to question.

Regards

Dave

On small, 1 to 2 cm parts that have been lost wax cast for me by Shapeways, I find a 2% shrinkage allowance is sufficient.

Dave

For what its worth, I use Ambersil Tufcut to power cut M6 threads on 303 stainless cold drawn rod with no problem, using an WM250V lathe on the lowest speed setting.

Dave

I use similar (Warco versions) in 3 axis form on my WM16 mill and 2 axis on the 250V lathe, both work fine.

Mick

There was nothing evident . When It broke I was taken a 0.5mm cut, so nothing big. I agree it could have been something lodged somewhere that moved. Carriage actually runs better now than it ever did. Just got to sort out stiff spot on the x axis on my wm16 now😂

Dave