Ready Steady Eddy

[Clive S]

The resin appears to be identical to the West System in this application, Epoxy Resin ideal for fibreglass repair and general use
21.85 GBP + VAT + shipping

I'm sorry Eddy but how can you say it is identical unless you have tried both types, I seem to remember you had a small problem with sinkage after about 3 days and you had to refill the surface I did not have that problem at all, I did not have any surface problems, the cure did not start for about 6 hours so plenty of time for it to settle. I am not trying to dis you by any means but I think it is only fair to others that are reading this to know the facts and it is up to their choice which to use. The Wests System is about twice the price but you only use it once so you take your chance. I spoke with the people at Wests about the suitability of their product regarding the shrinkage and cure times etc they were more than helpful. Rant over, nice job by the way ..Clive

[Jonathan]

I'm sorry Eddy but how can you say it is identical unless you have tried both types, I seem to remember you had a small problem with sinkage after about 3 days and you had to refill the surface I did not have that problem at all, I did not have any surface problems, the cure did not start for about 6 hours so plenty of time for it to settle

+1

I'd consider the epoxy 'squashing' slightly when the rail was attached a bit of a disaster, but it all depends on what accuracy you're striving for.

[EddyCurrent]

I don't think anyone has tried both epoxy products side by side but it seemed to me that if there was a difference then I would not be able to tell. I tried marking it with a scriber and used a centre punch on it and both times it was as hard you could wish for.

It wasn't shrinkage, it was the fastened down rail compressing the epoxy slightly.

Maybe nobody has removed their rails to see if the epoxy has moved ? maybe everyone else let it cure longer than I did ? maybe I torqued the rails down harder ? maybe my environmental conditions meant it had to cure longer ?. There are so many variables it's not possible to compare two situations. All I know is it should be left as long as possible after 3 days before fitting the rails, I seem to remember seeing 9 days somewhere but can't find the reference again.

Also I do not see it as a bit of a disaster, this is a DIY solution, it would not be used in a commercial machine (I hope !). The amount of sinking I'm talking about is less than 10 thou. , the sinking was uniform along the length, it only occured along the 'feet' of the rail, not in the middle so was easy to repair using the 5 minute epoxy and an old credit card , even if I had not repaired it it would have been fine because both rails were still in the same plane.

[EddyCurrent]

Setting up the gantry rails. The top rail has been fitted alongside a straight edge parallel to the front face of the gantry, this is the bottom rail being positioned. I put a bearing block on the top rail and fastened a G-cramp to it, then I attached a DTI with a magnetic base to the G-cramp. Sliding the block along showed that the rails were within 0.002" of parallel. Now to drill, tap, and fit the bottom rail.

Attachment 11621

[Wobblycogs]

Have you managed to bolt those two pieces of box section together inside (middle picture in power #180)? I'd love to know how you managed that if you have. I seriously considered trying that but there was no way I could think to get my arm in the box section and tools would be hellishly fiddly.

[JAZZCNC]

the sinking was uniform along the length, it only occured along the 'feet' of the rail, not in the middle so was easy to repair using the 5 minute epoxy and an old credit card , even if I had not repaired it it would have been fine because both rails were still in the same plane.

Don't talk daft any sinkage is Bad news and complete disaster.!! . . . Plus if they have sank so how do you know they are on the same plane.? Impossible to say that without some way to measure.

All this said for wood use then this will still be plenty good enough so it wouldn't bother me.

Regards the Epoxy then I agree West is Good and market leader but I've used other Infusion resin Epoxy's with no problems. Believe Rushing was your problem.!!

[EddyCurrent]

Don't talk daft any sinkage is Bad news and complete disaster.!! . . . Plus if they have sank so how do you know they are on the same plane.? Impossible to say that without some way to measure.

Over the years I've not had many 'disasters' that could not be recovered from, in fact working in Engineering Maintenance it's not even an option. In this case one method would have been to remove the epoxy and start again but I chose the method I did because that was fine for me, anyone else should choose their own recovery method.

I measured using a DTI from the face of the surrounding epoxy that had not been touched, I have 10mm each side of the rail 'spare'

All this said for wood use then this will still be plenty good enough so it wouldn't bother me.

Same here

Regards the Epoxy then I agree West is Good and market leader but I've used other Infusion resin Epoxy's with no problems. Believe Rushing was your problem.!!

I'm sure there are other resins that can do the job as you say.
Yes, rushing was most likely the problem.

[Lee Roberts]

Looking sweet eddy, keep up the good work.

.Me

[EddyCurrent]

Have you managed to bolt those two pieces of box section together inside (middle picture in power #180)? I'd love to know how you managed that if you have. I seriously considered trying that but there was no way I could think to get my arm in the box section and tools would be hellishly fiddly.

The rails on the gantry are 800mm long, they have 15 bolt holes. When I drilled the holes in the gantry to mount the bottom rail I made every other one 6.5mm, the others were 3.2mm tapping size. The 6.5mm holes, all 7 of them, were drilled right through both box sections to take 6mm hex bolts and that's what you can see in the photo. To get the bolts in the holes I used a magnet on a telescopic rod (Aldi's best), to get the nuts on I used a long thin piece of wood with double sided tape on one end. To the tape I stuck a nut, put some Loctite in it and 'stuck' a spring washer to it also with Loctite, this was lowered into the box section and using a long allen key on the head of the hex bolts (through the 6.5mm hole) I managed to attach both washer and nut. The other end of the thin stick had a taper or wedge cut out of it and this was used to stop the nut turning by wedging the stick between it and the inside face of the box section, the bolt was then tightened.
I glued a piece of 6x30 mild steel flat bar inside the box section then drilled and tapped all 15 holes for the rail thus making all 15 holes 3.2mm tapping size.

6x30mm flat bar glued inside to provide tapped holes for bottom gantry rail mounting.



Stick, telescopic magnet

[EddyCurrent]

Once I got the rails fitted to the gantry and the two lower bearing blocks added it was easy to see how to square everything up.
The gantry is bolted to the carriages at each end, the bolts were left slightly loose until the whole assembly was squared.



First an engineers square was adjusted to be exactly 90 deg. by using the flip over method mentioned previously, the fact it's a cheap Aldi one does not matter as you will see.
As silyavski pointed out recently, the Hiwin rails and bearing blocks have a machined side that should be used as a datum, so to these faces of the lower bearing blocks I clamped the engineers square.



All I had to do then was measure the distance between the engineers square and the long rails using a vernier. This was done at the end of the square and right up at the gantry so obviously when they read the same the gantry is at right angles to the long rails. The key point is that it's the two sets of rails that are being squared and not just the gantry frame. Also with regard to the cheap square, it can now be slid over to the other side of the gantry as it's clamped to the bearing blocks, and a similar reading can be made with the vernier. If the square was out of adjustment then the error would be multiplied at this side because the two long rails are exactly parallel. Once everything was adjusted the gantry securing bolts were tightened.